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• 13101. [Article] Migration of E. coli and solutes to tile drains via preferential and matrix flow

  The extent of agricultural drainage has created concern for its potential undesirable effects on surface water quality. Land applications of liquid manure on tile drain fields have the potential to transport ...

  Citation × Citation Citation Abstract Copy Title: Migration of E. coli and solutes to tile drains via preferential and matrix flow Author: Moreno, Daniel The extent of agricultural drainage has created concern for its potential undesirable effects on surface water quality. Land applications of liquid manure on tile drain fields have the potential to transport solutes and bacteria to the drains following precipitation or irrigation events and many times are directly sent to a surface water body, and have been documented as a source of contamination of surface waters. This study determined the potential for and magnitude of E. coli and solute migration to tile drains through the soil profile. Water from subsurface drains was analyzed for chemical and bacterial composition following tracer applications. Two sites were selected for the study to determine transport at large (field) and small (plot) scales. At the large-scale site, both tracers, bacteria (E. coli and Total Coliform) and Amino-G (a conservative tracer), were used to monitor the speed of transport from the surface to the tile drain following liquid manure applications, tracer applications and additionally precipitation events. The concentrations of E. coli were monitored every hour for 76 days during the spring. Both tracers, bacteria and Amino-G, were detected in the tile drainage shortly after precipitation events. The peak concentration of E. coli was observed to be 1.2 x 10⁶ CFU/l00mL. These elevated concentrations of E. coli might be attributed to the characteristics of the soil, high organic matter and well-structured clay soils. Both the rapid breakthrough of tracer to the tile drain and the peaks of tile water temperature during precipitation events provided evidence of macropore flow. Antecedent soil moisture and warmer temperatures appeared to provide ideal conditions for bacteria growth. The small-scale study site was selected for a more focused study. The purpose of this site was to quantify more accurately the percent mass of surface applied tracer that was transported to the tile drain, allowing mass balance calculations. Experiments were conducted during the summer to control the rate and total amount of irrigation. Amino-G readings were taken every 10 seconds for 125 hours of continuous irrigation. Tracer applications were conducted at runoff and non-runoff conditions. Both types of tracer applications had Amino-G breakthrough in less than 10 minutes after initiation of irrigation. Tracer applied at runoff rates resulted in 4 to 17 times more total tracer mass migrating to the tile drain than when applied at non-runoff rates. The total mass of Amino-G migrating to the tile drain during non-runoff conditions depended on the total volume of applied tracer, regardless of the tracer concentration. For an application of 5.6 mm at 12 mg/L, 5.7% of the total applied tracer migrated to the tile drain, whereas for an application of 1.9 mm at 27.7 mg/L only 2.8% of the total applied tracer migrated to the tile drain. Tile flow response to irrigation experiments appeared to be governed by soil moisture. Lysimeter samples were taken continuously every 4-8 hours until the 94th hour after tracer application. Tile water concentrations were consistently greater than concentrations found in the deeper suction lysimeters at corresponding times, providing further evidence of preferential flow. E. coli transported through the soil and into the drains were demonstrated to be event-driven by precipitation events and irrigation events. In addition, the characteristics of this type of soil - the high clay content, the well-defined structure, the high level of organic matter and rich biological activity has been known to enhance the preferential pathways and transport processes in the soil profile, resulting in rapid transport of surface applied solutes and effluents to tile drains. Title: Migration of E. coli and solutes to tile drains via preferential and matrix flow Author: Moreno, Daniel The extent of agricultural drainage has created concern for its potential undesirable effects on surface water quality. Land applications of liquid manure on tile drain fields have the potential to transport solutes and bacteria to the drains following precipitation or irrigation events and many times are directly sent to a surface water body, and have been documented as a source of contamination of surface waters. This study determined the potential for and magnitude of E. coli and solute migration to tile drains through the soil profile. Water from subsurface drains was analyzed for chemical and bacterial composition following tracer applications. Two sites were selected for the study to determine transport at large (field) and small (plot) scales. At the large-scale site, both tracers, bacteria (E. coli and Total Coliform) and Amino-G (a conservative tracer), were used to monitor the speed of transport from the surface to the tile drain following liquid manure applications, tracer applications and additionally precipitation events. The concentrations of E. coli were monitored every hour for 76 days during the spring. Both tracers, bacteria and Amino-G, were detected in the tile drainage shortly after precipitation events. The peak concentration of E. coli was observed to be 1.2 x 10⁶ CFU/l00mL. These elevated concentrations of E. coli might be attributed to the characteristics of the soil, high organic matter and well-structured clay soils. Both the rapid breakthrough of tracer to the tile drain and the peaks of tile water temperature during precipitation events provided evidence of macropore flow. Antecedent soil moisture and warmer temperatures appeared to provide ideal conditions for bacteria growth. The small-scale study site was selected for a more focused study. The purpose of this site was to quantify more accurately the percent mass of surface applied tracer that was transported to the tile drain, allowing mass balance calculations. Experiments were conducted during the summer to control the rate and total amount of irrigation. Amino-G readings were taken every 10 seconds for 125 hours of continuous irrigation. Tracer applications were conducted at runoff and non-runoff conditions. Both types of tracer applications had Amino-G breakthrough in less than 10 minutes after initiation of irrigation. Tracer applied at runoff rates resulted in 4 to 17 times more total tracer mass migrating to the tile drain than when applied at non-runoff rates. The total mass of Amino-G migrating to the tile drain during non-runoff conditions depended on the total volume of applied tracer, regardless of the tracer concentration. For an application of 5.6 mm at 12 mg/L, 5.7% of the total applied tracer migrated to the tile drain, whereas for an application of 1.9 mm at 27.7 mg/L only 2.8% of the total applied tracer migrated to the tile drain. Tile flow response to irrigation experiments appeared to be governed by soil moisture. Lysimeter samples were taken continuously every 4-8 hours until the 94th hour after tracer application. Tile water concentrations were consistently greater than concentrations found in the deeper suction lysimeters at corresponding times, providing further evidence of preferential flow. E. coli transported through the soil and into the drains were demonstrated to be event-driven by precipitation events and irrigation events. In addition, the characteristics of this type of soil - the high clay content, the well-defined structure, the high level of organic matter and rich biological activity has been known to enhance the preferential pathways and transport processes in the soil profile, resulting in rapid transport of surface applied solutes and effluents to tile drains. Close

• 13102. [Article] Model Predictive Control for Optimum Algal Growth

  Microalgae has been under careful consideration as a sustainable feedstock for renewable fuel recently due to its year round production with high energy yields per unit area, reduced need for arable land, ...

  Citation × Citation Citation Abstract Copy Title: Model Predictive Control for Optimum Algal Growth Author: Juneja, Ankita Microalgae has been under careful consideration as a sustainable feedstock for renewable fuel recently due to its year round production with high energy yields per unit area, reduced need for arable land, water treatment benefits with nutrient cycling, and minimal competition with the food industry. Despite of all these advantages, commercialization of algal biofuels still lacks economic viability, mainly because of lower productivities and higher cost of harvesting and processing of algae. Photobioreactors are able to provide high yields of algae but they suffer from limitation of high initial cost, whereas growth in low-cost open ponds are highly affected by external factors such as ambient temperature, light availability and contamination with other micro-organisms. These external factors inhibit a consistent growth, which consequently reduces the final productivity of algae. There is an imminent need to find a solution that can take into account the objectives of maximum productivity with minimum economic and environmental effects. The focus of this dissertation was to design, implement and validate a model predictive control which can assure optimum algal growth and productivity, even under the effect of disturbances. The dissertation was divided into four studies, each of which concentrates on developing different models to be integrated in the design of the model predictive controller. In the first study, a compartmentalized genome scale metabolic network was reconstructed for C. variabilis to offer insight into various metabolic potentials from this alga. The model iAJ526 was reconstructed with 1455 reactions, metabolites and 526 genes. 21% of the reactions were transport reactions and about 81% of the total reactions were associated with enzymes. Model was able to simulate experimental batch growth conditions with fair agreement under three light conditions. The discrepancy in experimental and model results was attributed to the incapability of the model to capture kinetics of growth, including substrate inhibition and photoinhibition. Cumulative wavelengths around 437 nm, 673 nm and 680 nm in the model were observed to be 100% efficient in their utilization. The second study evaluated the economic viability and to estimate the energy use and greenhouse gas (GHG) emissions during life cycle of renewable diesel (RD) production from algae via hydrothermal liquefaction process. Hydrothermal liquefaction is one such technology that converts the algae into high heating value bio-oil under high temperature and pressure. RD yields for algae were estimated 10.19 ML/year unit price of production as $1.75/L RD. Energy and emissions were calculated per functional unit which was defined as 1000 MJ of available energy in fuel at the pump. Fossil energies were calculated as 241.6MJ to produce one functional unit of RD from algae. The GHG emissions during life cycle of RD production were found to be 6.2 times less than those produced for 1000MJ of conventional diesel. In the third project, Monod's multiplicative kinetic model for Chlorella vulgaris, one of the most robust algal strains for outdoor growth, was developed with limiting nitrate and CO₂. The specific growth rate calculated from the growth profiles was 0.0196 hr⁻¹. The values of μ_max, k_N, k_C, k_d, Ea and k_L a were estimated as 0.23 hr⁻¹, 26.53 mg/l, 7.64 mg/l, 0.08hr⁻¹, 3.69 J/mol and 0.24 hr⁻¹. The yield coefficient for nitrate (Y_(X⁄N)) and CO₂ (Y_(X⁄C)) for C. vulgaris were calculated as 2.86 and 1.96 respectively. Validation experiments proved the kinetic model to be robust under vast range of initial biomass and nitrate concentrations. The kinetic model developed, formed the basis of the model predictive control (MPC) designed for optimum growth of algae, with an objective of maximizing productivity and minimizing the total cost and GHG emissions. The MPC proved to be an efficient tool that can help in a steady growth even under natural disturbances. The growth of algae under the light and temperature disturbances tested was higher in the reactor with MPC than the other reactor with no MPC. However, due to light limitation, the growth with low light of 34W/m² (simulating a cloudy day) in the MPC reactor was not different form the other one with no MPC. This disturbance was considered outside the realm of controller as the control variables or the manipulated variables were not able to overcome light limitation. In absence of any disturbance, the growth in MPC reactor was not statistically different form the no MPC reactor. This shows the importance of MPC under conditions deviating from the optimum, which is a common case in real time outdoor ponds. Title: Model Predictive Control for Optimum Algal Growth Author: Juneja, Ankita Microalgae has been under careful consideration as a sustainable feedstock for renewable fuel recently due to its year round production with high energy yields per unit area, reduced need for arable land, water treatment benefits with nutrient cycling, and minimal competition with the food industry. Despite of all these advantages, commercialization of algal biofuels still lacks economic viability, mainly because of lower productivities and higher cost of harvesting and processing of algae. Photobioreactors are able to provide high yields of algae but they suffer from limitation of high initial cost, whereas growth in low-cost open ponds are highly affected by external factors such as ambient temperature, light availability and contamination with other micro-organisms. These external factors inhibit a consistent growth, which consequently reduces the final productivity of algae. There is an imminent need to find a solution that can take into account the objectives of maximum productivity with minimum economic and environmental effects. The focus of this dissertation was to design, implement and validate a model predictive control which can assure optimum algal growth and productivity, even under the effect of disturbances. The dissertation was divided into four studies, each of which concentrates on developing different models to be integrated in the design of the model predictive controller. In the first study, a compartmentalized genome scale metabolic network was reconstructed for C. variabilis to offer insight into various metabolic potentials from this alga. The model iAJ526 was reconstructed with 1455 reactions, metabolites and 526 genes. 21% of the reactions were transport reactions and about 81% of the total reactions were associated with enzymes. Model was able to simulate experimental batch growth conditions with fair agreement under three light conditions. The discrepancy in experimental and model results was attributed to the incapability of the model to capture kinetics of growth, including substrate inhibition and photoinhibition. Cumulative wavelengths around 437 nm, 673 nm and 680 nm in the model were observed to be 100% efficient in their utilization. The second study evaluated the economic viability and to estimate the energy use and greenhouse gas (GHG) emissions during life cycle of renewable diesel (RD) production from algae via hydrothermal liquefaction process. Hydrothermal liquefaction is one such technology that converts the algae into high heating value bio-oil under high temperature and pressure. RD yields for algae were estimated 10.19 ML/year unit price of production as $1.75/L RD. Energy and emissions were calculated per functional unit which was defined as 1000 MJ of available energy in fuel at the pump. Fossil energies were calculated as 241.6MJ to produce one functional unit of RD from algae. The GHG emissions during life cycle of RD production were found to be 6.2 times less than those produced for 1000MJ of conventional diesel. In the third project, Monod's multiplicative kinetic model for Chlorella vulgaris, one of the most robust algal strains for outdoor growth, was developed with limiting nitrate and CO₂. The specific growth rate calculated from the growth profiles was 0.0196 hr⁻¹. The values of μ_max, k_N, k_C, k_d, Ea and k_L a were estimated as 0.23 hr⁻¹, 26.53 mg/l, 7.64 mg/l, 0.08hr⁻¹, 3.69 J/mol and 0.24 hr⁻¹. The yield coefficient for nitrate (Y_(X⁄N)) and CO₂ (Y_(X⁄C)) for C. vulgaris were calculated as 2.86 and 1.96 respectively. Validation experiments proved the kinetic model to be robust under vast range of initial biomass and nitrate concentrations. The kinetic model developed, formed the basis of the model predictive control (MPC) designed for optimum growth of algae, with an objective of maximizing productivity and minimizing the total cost and GHG emissions. The MPC proved to be an efficient tool that can help in a steady growth even under natural disturbances. The growth of algae under the light and temperature disturbances tested was higher in the reactor with MPC than the other reactor with no MPC. However, due to light limitation, the growth with low light of 34W/m² (simulating a cloudy day) in the MPC reactor was not different form the other one with no MPC. This disturbance was considered outside the realm of controller as the control variables or the manipulated variables were not able to overcome light limitation. In absence of any disturbance, the growth in MPC reactor was not statistically different form the no MPC reactor. This shows the importance of MPC under conditions deviating from the optimum, which is a common case in real time outdoor ponds. Close

• 13103. [Article] Aspects of the physiology and diseases of the North American elk

  Several aspects of the physiology and diseases of the North American elk (Cervus canadensis) were investigated, toward the goal of uncovering influences responsible for declining productivity among some ...

  Citation × Citation Citation Abstract Copy Title: Aspects of the physiology and diseases of the North American elk Author: Weber, Yvonne Bernard Year: 1973 Several aspects of the physiology and diseases of the North American elk (Cervus canadensis) were investigated, toward the goal of uncovering influences responsible for declining productivity among some elk herds in Oregon. A newly developed drug, Etorphine, together with its antagonistic companion, Dip renorphine, was used to immobilize elk. Substantial differences were found in the amounts required and animal responses dependent upon age, physical condition and life history. Whole blood samples were obtained from 60 living elk for hematological studies. The parameters examined included hemoglobin levels, packed cell volume, erythrocyte and leukocyte counts, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, mean corpuscular volume, and the percentage distribution of neutrophils, band cells, lymphocytes, monocytes, eosinophils, and basophils. Respiration rate, heart rate, and body temperature were measured for nine drugged elk. Sickling of erythrocytes was found in the blood of two female elk. Serum was separated from the blood of 72 living elk and 22 recently shot elk of mixed ages and sexes. Serum proteins were differentiated by electrophoretic analysis. Values obtained for total protein, albumin, total globulin, albumin/globulin ratio, and for the alpha1, alpha2, beta and gamma globulins, were grouped and summarized to facilitate comparisons based on age and sex, as well as between living and dead, and captive and free-living elk. Total serum protein concentrations were markedly higher in the older age groups of both captive and freeliving elk. An apparent tendency to higher albumin levels was found among males of this species. Values for serum concentrations of sodium, potassium, calcium, inorganic phosphorus, blood urea nitrogen, Chlorides, Cholesterol, glucose, direct bilirubin, total bilirubin, creatinine, and uric acid, as well as activity levels of alkaline phosphatase, lactic dehydrogenase, and serum glutamic oxalacetic transaminase were obtained. Sodium/ potassium and calCium/phosphorus ratios were calculated. Urine speciments were obtained from seven elk and analyzed for the presence of glucose. Young elk, both captive and free-living, had higher serum values for sodium, calcium, inorganic phosphorus, glucose and alkaline phosphatase than did the older age group. Mature elk, both captive and free-living, had higher serum values for calcium/phosphorus ratio, blood urea nitrogen, creatinine, uric acid and serum glutamic oxalacetic transaminase than did those under two years of age. Differences in serum Chemistry were also found between captive and free-living elk. Serological tests on sera from 67 elk tested were negative for brucellosis and bluetongue virus. Tests for leptospirosis on sera from 29 elk by the macroscopic agglutination method were all negative. Of 38 free-living elk tested for leptospirosis by the microscopic agglutination test, 16 showed positive reactions to one or more serotypes at a significant titer of 1:100 or greater. Another eight showed positive reactions at the 1:50 level. This is believed to the first report of serological reactivity to leptospirosis reported for elk. Internal organs from 39 elk were examined for the presence of adult helminths, and fecal pellets from 82 elk were examined for the presence of parasite eggs. Lethal numbers of Dictyocaulus viviparus were recovered from the respiratory organs of two yearling male elk. Two nematodes of the Trichostrongylus axei and Ostertagia circumcincta, were found that have not been previously reported from Roosevelt elk. Fascioloides magna and Oesophagostomum venulosum were also found. The common winter tick, Dermacentor albipictus and Ixodes pacificus were collected from Roosevelt elk. This latter species has not been previously reported in elk. Increased gannna globulin values and concomitant decreases in albumin were observed in tick-infested elk. Title: Aspects of the physiology and diseases of the North American elk Author: Weber, Yvonne Bernard Year: 1973 Several aspects of the physiology and diseases of the North American elk (Cervus canadensis) were investigated, toward the goal of uncovering influences responsible for declining productivity among some elk herds in Oregon. A newly developed drug, Etorphine, together with its antagonistic companion, Dip renorphine, was used to immobilize elk. Substantial differences were found in the amounts required and animal responses dependent upon age, physical condition and life history. Whole blood samples were obtained from 60 living elk for hematological studies. The parameters examined included hemoglobin levels, packed cell volume, erythrocyte and leukocyte counts, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, mean corpuscular volume, and the percentage distribution of neutrophils, band cells, lymphocytes, monocytes, eosinophils, and basophils. Respiration rate, heart rate, and body temperature were measured for nine drugged elk. Sickling of erythrocytes was found in the blood of two female elk. Serum was separated from the blood of 72 living elk and 22 recently shot elk of mixed ages and sexes. Serum proteins were differentiated by electrophoretic analysis. Values obtained for total protein, albumin, total globulin, albumin/globulin ratio, and for the alpha1, alpha2, beta and gamma globulins, were grouped and summarized to facilitate comparisons based on age and sex, as well as between living and dead, and captive and free-living elk. Total serum protein concentrations were markedly higher in the older age groups of both captive and freeliving elk. An apparent tendency to higher albumin levels was found among males of this species. Values for serum concentrations of sodium, potassium, calcium, inorganic phosphorus, blood urea nitrogen, Chlorides, Cholesterol, glucose, direct bilirubin, total bilirubin, creatinine, and uric acid, as well as activity levels of alkaline phosphatase, lactic dehydrogenase, and serum glutamic oxalacetic transaminase were obtained. Sodium/ potassium and calCium/phosphorus ratios were calculated. Urine speciments were obtained from seven elk and analyzed for the presence of glucose. Young elk, both captive and free-living, had higher serum values for sodium, calcium, inorganic phosphorus, glucose and alkaline phosphatase than did the older age group. Mature elk, both captive and free-living, had higher serum values for calcium/phosphorus ratio, blood urea nitrogen, creatinine, uric acid and serum glutamic oxalacetic transaminase than did those under two years of age. Differences in serum Chemistry were also found between captive and free-living elk. Serological tests on sera from 67 elk tested were negative for brucellosis and bluetongue virus. Tests for leptospirosis on sera from 29 elk by the macroscopic agglutination method were all negative. Of 38 free-living elk tested for leptospirosis by the microscopic agglutination test, 16 showed positive reactions to one or more serotypes at a significant titer of 1:100 or greater. Another eight showed positive reactions at the 1:50 level. This is believed to the first report of serological reactivity to leptospirosis reported for elk. Internal organs from 39 elk were examined for the presence of adult helminths, and fecal pellets from 82 elk were examined for the presence of parasite eggs. Lethal numbers of Dictyocaulus viviparus were recovered from the respiratory organs of two yearling male elk. Two nematodes of the Trichostrongylus axei and Ostertagia circumcincta, were found that have not been previously reported from Roosevelt elk. Fascioloides magna and Oesophagostomum venulosum were also found. The common winter tick, Dermacentor albipictus and Ixodes pacificus were collected from Roosevelt elk. This latter species has not been previously reported in elk. Increased gannna globulin values and concomitant decreases in albumin were observed in tick-infested elk. Close

• 13104. [Article] Study of Prestige and Resource Control Using Fish Remains from Cathlapotle, a Plankhouse Village on the Lower Columbia River

  Social inequality is a trademark of Northwest Coast native societies, and the relationship between social prestige and resource control, particularly resource ownership, is an important research issue ...

  Citation × Citation Citation Abstract Copy Title: Study of Prestige and Resource Control Using Fish Remains from Cathlapotle, a Plankhouse Village on the Lower Columbia River Author: Rosenberg, J. Shoshana Year: 2015 Social inequality is a trademark of Northwest Coast native societies, and the relationship between social prestige and resource control, particularly resource ownership, is an important research issue on the Northwest Coast. Faunal remains are one potential but as yet underutilized path for examining this relationship. My thesis work takes on this approach through the analysis of fish remains from the Cathlapotle archaeological site (45CL1). Cathlapotle is a large Chinookan village site located on the Lower Columbia River that was extensively excavated in the 1990s. Previous work has established prestige distinctions between houses and house compartments, making it possible to examine the relationship between prestige and the spatial distribution of fish remains. In this study, I examine whether having high prestige afforded its bearers greater access to preferred fish, utilizing comparisons of fish remains at two different levels of social organization, between and within households, to determine which social mechanisms could account for potential differences in access to fish resources. Differential access to these resources within the village could have occurred through household-level ownership of harvesting sites or control over the post-harvesting distribution of food by certain individuals. Previous work in this region on the relationship between faunal remains and prestige has relied heavily on ethnohistoric sources to determine the relative value of taxa. These sources do not provide adequate data to make detailed comparisons between all of the taxa encountered at archaeological sites, so in this study I utilize optimal foraging theory as an alternative means of determining which fish taxa were preferred. Optimal foraging theory provides a universal, quantitative analytical rule for ranking fish that I was able to apply to all of the taxa encountered at Cathlapotle. Given these rankings, which are based primarily on size, I examine the degree to which relative prestige designations of two households (Houses 1 and 4) and compartments within one of those households (House 1) are reflected in the spatial distribution of fish remains. I also offer a new method for quantifying sturgeon that utilizes specimen weight to account for differential fragmentation rates while still allowing for sturgeon abundance to be compared to the abundances of other taxa that have been quantified by number of identified specimens (NISP). Based on remains recovered from 1/4" mesh screens, comparisons between compartments within House 1 indicate that the chief and possibly other elite members of House 1 likely had some control over the distribution of fish resources within their household, taking more of the preferred sturgeon and salmon, particularly more chinook salmon, for themselves. Comparisons between households provide little evidence to support household-based ownership of fishing sites. A greater abundance of chinook salmon in the higher prestige House 1 may indicate ownership of fishing platforms at major chinook fisheries such as Willamette Falls or Cascades Rapids, but other explanations for this difference between households are possible. Analyses of a limited number of bulk samples, which were included in the study in order to examine utilization of very small fishes, provided insufficient data to allow for meaningful intrasite comparisons. These data indicate that the inhabitants of Cathlapotle were exploiting a broad fish subsistence base that included large numbers of eulachon and stickleback in addition to the larger fishes. This study provides a promising approach for examining prestige on the Northwest Coast and expanding our understanding of the dynamics between social inequality and resource access and control. Title: Study of Prestige and Resource Control Using Fish Remains from Cathlapotle, a Plankhouse Village on the Lower Columbia River Author: Rosenberg, J. Shoshana Year: 2015 Social inequality is a trademark of Northwest Coast native societies, and the relationship between social prestige and resource control, particularly resource ownership, is an important research issue on the Northwest Coast. Faunal remains are one potential but as yet underutilized path for examining this relationship. My thesis work takes on this approach through the analysis of fish remains from the Cathlapotle archaeological site (45CL1). Cathlapotle is a large Chinookan village site located on the Lower Columbia River that was extensively excavated in the 1990s. Previous work has established prestige distinctions between houses and house compartments, making it possible to examine the relationship between prestige and the spatial distribution of fish remains. In this study, I examine whether having high prestige afforded its bearers greater access to preferred fish, utilizing comparisons of fish remains at two different levels of social organization, between and within households, to determine which social mechanisms could account for potential differences in access to fish resources. Differential access to these resources within the village could have occurred through household-level ownership of harvesting sites or control over the post-harvesting distribution of food by certain individuals. Previous work in this region on the relationship between faunal remains and prestige has relied heavily on ethnohistoric sources to determine the relative value of taxa. These sources do not provide adequate data to make detailed comparisons between all of the taxa encountered at archaeological sites, so in this study I utilize optimal foraging theory as an alternative means of determining which fish taxa were preferred. Optimal foraging theory provides a universal, quantitative analytical rule for ranking fish that I was able to apply to all of the taxa encountered at Cathlapotle. Given these rankings, which are based primarily on size, I examine the degree to which relative prestige designations of two households (Houses 1 and 4) and compartments within one of those households (House 1) are reflected in the spatial distribution of fish remains. I also offer a new method for quantifying sturgeon that utilizes specimen weight to account for differential fragmentation rates while still allowing for sturgeon abundance to be compared to the abundances of other taxa that have been quantified by number of identified specimens (NISP). Based on remains recovered from 1/4" mesh screens, comparisons between compartments within House 1 indicate that the chief and possibly other elite members of House 1 likely had some control over the distribution of fish resources within their household, taking more of the preferred sturgeon and salmon, particularly more chinook salmon, for themselves. Comparisons between households provide little evidence to support household-based ownership of fishing sites. A greater abundance of chinook salmon in the higher prestige House 1 may indicate ownership of fishing platforms at major chinook fisheries such as Willamette Falls or Cascades Rapids, but other explanations for this difference between households are possible. Analyses of a limited number of bulk samples, which were included in the study in order to examine utilization of very small fishes, provided insufficient data to allow for meaningful intrasite comparisons. These data indicate that the inhabitants of Cathlapotle were exploiting a broad fish subsistence base that included large numbers of eulachon and stickleback in addition to the larger fishes. This study provides a promising approach for examining prestige on the Northwest Coast and expanding our understanding of the dynamics between social inequality and resource access and control. Close

• 13105. [Article] The Educational values of trees and forests

  Authors' affiliation/contact: Department of Environment and Society, Utah State University, Logan, UT 84322-5215 (Terry.Sharik@usu.edu)

  Citation × Citation Citation Abstract Copy Title: The Educational values of trees and forests Author: Sharik, Terry L., Frisk, Stacey Authors' affiliation/contact: Department of Environment and Society, Utah State University, Logan, UT 84322-5215 (Terry.Sharik@usu.edu) Title: The Educational values of trees and forests Author: Sharik, Terry L., Frisk, Stacey Authors' affiliation/contact: Department of Environment and Society, Utah State University, Logan, UT 84322-5215 (Terry.Sharik@usu.edu) Close

• 13106. [Article] Spinal reflex control in healthy and ACL-injured women during a distracting task

  Female athletes exhibit three- to six-fold greater incidence of noncontact anterior cruciate ligament (ACL) injury relative to their male counterparts. The increased risk appears to stem from interactions ...

  Citation × Citation Citation Abstract Copy Title: Spinal reflex control in healthy and ACL-injured women during a distracting task Author: Perrier, Erica Taylor Female athletes exhibit three- to six-fold greater incidence of noncontact anterior cruciate ligament (ACL) injury relative to their male counterparts. The increased risk appears to stem from interactions between several risk factors, that can roughly be categorized as anatomic, biomechanical, hormonal, and neuromuscular. Neuromuscular risk factors have recently gained a greater focus, and include differences in the timing and magnitude of activation of lower extremity and trunk musculature. In addition to neuromuscular risk factors, the incidence of ACL injury is not evenly distributed across the menstrual cycle, suggesting that hormonal fluctuations may influence neuromuscular control. Finally, it is known that even well-trained athletes experience decrements in performance and postural control when forced to attend to multiple sensory stimuli, which is common in many sports. PURPOSE: To explore neuromuscular differences in the ways healthy and ACL-injured women respond to a secondary task requiring fine motor control and sustained mental focus (typing task). Our investigation encompassed three broad aims. First, we sought to determine whether ACL-injured individuals demonstrated similar reflex profiles to healthy individuals, as well as to determine whether the ACL-involved limb was similar to its uninvolved counterpart. Our second aim was to determine whether the typing task resulted in attenuated Hoffmann (H) reflex amplitudes, and to investigate whether any observed changes were similar in healthy and ACL-injured groups. Finally, our third broad aim was to utilize more complex H reflex analysis techniques to determine whether differences in spinal excitability existed at different points in the menstrual cycle. METHODS: Thirty nine recreationally active women (20 with prior unilateral noncontact ACL injury: 24.0 ± 4.5 years; 23.8 ± 4.5 kg•m⁻²; 4.1 ± 2.6 years post-injury; 19 with no history of knee injury: 23.8 ± 4.5 years; 23.1 ± 2.3 kg•m⁻²) agreed to participate, and were tested during days 2-5 (follicular phase) of the menstrual cycle. A sub-set of this original group (n=8; 24.0 ± 4.8 years; 22.0 ± 2.1 kg•m⁻²) also agreed to return for a second testing session 24-96 hours after ovulation (early luteal phase), in order to assess H reflex differences across the menstrual cycle. During each testing session, H reflex testing was used to explore spinal-level control mechanisms of the lower extremity musculature under both Rest and Task conditions. In the control group, the dominant limb was tested (CON-D) while in the ACL group, both the uninvolved (ACL-UN) and involved (ACL-INV) limbs were assessed. Differences between groups (Control vs. ACL) and within-groups (ACL-UN vs. ACL-INV) were explored. RESULTS: At rest, H reflex parameters in ACL-INV were generally similar to ACL-UN and to CON-D. However, differences in presynaptic inhibition were apparent in ACL-INV that imply reduced reflex plasticity. During the typing task, both the Control and ACL groups experienced attenuated H reflex parameters. In the sub-set of participants who were tested twice during the menstrual cycle, a significant increase in presynaptic inhibition was observed during the early luteal phase compared to the follicular phase. CONCLUSION: While individuals with prior ACL injury display similar H reflex profiles to healthy individuals, the ACL-involved limb may demonstrate less reflex plasticity in response to environmental changes. This lack of plasticity may potentially increase the risk of re-injury. In addition, an upper extremity task requiring fine motor control and sustained mental focus attenuates the H reflex in both groups. This attenuation has implications for lower-extremity neuromuscular control in dual-task environments. Finally, the increase in presynaptic inhibition observed during the early luteal phase may provide insight into why ACL injuries are not evenly distributed across the menstrual cycle. Title: Spinal reflex control in healthy and ACL-injured women during a distracting task Author: Perrier, Erica Taylor Female athletes exhibit three- to six-fold greater incidence of noncontact anterior cruciate ligament (ACL) injury relative to their male counterparts. The increased risk appears to stem from interactions between several risk factors, that can roughly be categorized as anatomic, biomechanical, hormonal, and neuromuscular. Neuromuscular risk factors have recently gained a greater focus, and include differences in the timing and magnitude of activation of lower extremity and trunk musculature. In addition to neuromuscular risk factors, the incidence of ACL injury is not evenly distributed across the menstrual cycle, suggesting that hormonal fluctuations may influence neuromuscular control. Finally, it is known that even well-trained athletes experience decrements in performance and postural control when forced to attend to multiple sensory stimuli, which is common in many sports. PURPOSE: To explore neuromuscular differences in the ways healthy and ACL-injured women respond to a secondary task requiring fine motor control and sustained mental focus (typing task). Our investigation encompassed three broad aims. First, we sought to determine whether ACL-injured individuals demonstrated similar reflex profiles to healthy individuals, as well as to determine whether the ACL-involved limb was similar to its uninvolved counterpart. Our second aim was to determine whether the typing task resulted in attenuated Hoffmann (H) reflex amplitudes, and to investigate whether any observed changes were similar in healthy and ACL-injured groups. Finally, our third broad aim was to utilize more complex H reflex analysis techniques to determine whether differences in spinal excitability existed at different points in the menstrual cycle. METHODS: Thirty nine recreationally active women (20 with prior unilateral noncontact ACL injury: 24.0 ± 4.5 years; 23.8 ± 4.5 kg•m⁻²; 4.1 ± 2.6 years post-injury; 19 with no history of knee injury: 23.8 ± 4.5 years; 23.1 ± 2.3 kg•m⁻²) agreed to participate, and were tested during days 2-5 (follicular phase) of the menstrual cycle. A sub-set of this original group (n=8; 24.0 ± 4.8 years; 22.0 ± 2.1 kg•m⁻²) also agreed to return for a second testing session 24-96 hours after ovulation (early luteal phase), in order to assess H reflex differences across the menstrual cycle. During each testing session, H reflex testing was used to explore spinal-level control mechanisms of the lower extremity musculature under both Rest and Task conditions. In the control group, the dominant limb was tested (CON-D) while in the ACL group, both the uninvolved (ACL-UN) and involved (ACL-INV) limbs were assessed. Differences between groups (Control vs. ACL) and within-groups (ACL-UN vs. ACL-INV) were explored. RESULTS: At rest, H reflex parameters in ACL-INV were generally similar to ACL-UN and to CON-D. However, differences in presynaptic inhibition were apparent in ACL-INV that imply reduced reflex plasticity. During the typing task, both the Control and ACL groups experienced attenuated H reflex parameters. In the sub-set of participants who were tested twice during the menstrual cycle, a significant increase in presynaptic inhibition was observed during the early luteal phase compared to the follicular phase. CONCLUSION: While individuals with prior ACL injury display similar H reflex profiles to healthy individuals, the ACL-involved limb may demonstrate less reflex plasticity in response to environmental changes. This lack of plasticity may potentially increase the risk of re-injury. In addition, an upper extremity task requiring fine motor control and sustained mental focus attenuates the H reflex in both groups. This attenuation has implications for lower-extremity neuromuscular control in dual-task environments. Finally, the increase in presynaptic inhibition observed during the early luteal phase may provide insight into why ACL injuries are not evenly distributed across the menstrual cycle. Close

• 13107. [Article] Understanding large resurgent calderas and associated magma systems : the Pastos Grandes Caldera Complex, southwest Bolivia

  The Pastos Grandes Caldera Complex (PGCC) in southwest Bolivia has produced two large-volume (≥800 km³ DRE) dacite ignimbrites from a nested caldera source over a period of 5.5 Myr. In addition to the ...

  Citation × Citation Citation Abstract Copy Title: Understanding large resurgent calderas and associated magma systems : the Pastos Grandes Caldera Complex, southwest Bolivia Author: Kaiser, Jason Frederick, 1985- The Pastos Grandes Caldera Complex (PGCC) in southwest Bolivia has produced two large-volume (≥800 km³ DRE) dacite ignimbrites from a nested caldera source over a period of 5.5 Myr. In addition to the large-volume ignimbrites, a small-volume ignimbrite shield and post-climactic lavas define this composite system. Based on detailed field work and analysis of satellite imagery plus biotite ⁴⁰Ar/³⁹Ar dating, we summarize a revised stratigraphy, areal distribution and volume calculations for ignimbrites. From interpretations of stratigraphy and structures along the caldera margins, we propose an asymmetric collapse hinged along the north and western boundaries. Both the early Chuhuilla (5.45 ± 0.02 Ma), and the younger Pastos Grandes (2.89 ± 0.01 Ma) calderas share the hinge and much of the eastern collapse scarp, however the Chuhuilla caldera defines a much larger area (>1700 km²) compared to the Pastos Grandes (870 km²). It is proposed here that pre-existing regional tectonic weaknesses combined with influences of the magma body caused roof failure and caldera collapse. The vast majority of the ignimbrite volume lies within the Chuhuilla and Pastos Grandes calderas (92 and 75% respectively). Considerable intracaldera fill and the lack of preceding plinian deposits suggest that the caldera collapse was early and the eruptive column was not high and was short-lived. The physical properties of the ignimbrites, the limit of their areal distribution to regional topographic lows along with paleomagnetic characteristics support the idea of dense sluggish pyroclastic flows. New volume calculations using multiple methods update previous estimates, with the Chuhuilla now at approximately 1300 km³ and the Pastos Grandes at 800 km³. The ignimbrite volumes and spatial pattern of vents suggest that the caldera complex mirrors the construction of a long-lived composite batholith that focused spatially with time. Eruptions from the PGCC have produced compositionally restricted, high-K dacites with volumetrically minor rhyolites. Combined with granodiorite xenoliths, each caldera cycle contains a progression of textural maturity from ignimbrite, through post-climactic lavas, to remnant pluton. The chemical signatures in the PGCC mirror those of the host Altiplano Puna Volcanic Complex (APVC) and resemble typical arc characteristics (i.e. LIL enriched magmas - Ba/Nb of 4.7-4.8 and Ba/La of 1.6-2.0). However, overprinted on the arc signature are elevated radiogenic isotopes (⁸⁷Sr/⁸⁶Sr ~0.708 - 0.709), which suggest high degrees of crustal assimilation that is thought to be related to increased mantle input from melted asthenosphere. It is suggested here that a combination of assimilation and fractional crystallization from the regional mid-crustal parental source would create the magmas erupted in the PGCC. Subtle decreases in the ⁸⁷Sr/⁸⁶Sr from the Chuhuilla caldera cycle, to the younger Pastos Grandes cycle suggest higher amounts of crustal assimilation related to more heat flow during the peak of the flare up. Zircon chronochemistry reveals that the climactic, caldera-forming eruptions of the PGCC punctuate the protracted magma accumulation and storage periods. The combination of in-situ zircon U-Pb ages with indicators for geochemical evolution (e.g., Zr/Hf, Yb/Gd, Eu/Eu*, Th, U) magmatic temperatures (e.g., Ti) in zircon, reveals protracted magma presence before and after the climactic 2.89 ± 0.01 Ma Pastos Grandes Ignimbrite (PGI) supereruption (~800 km³ of magma) in southwest Bolivia. Zircons from PGI pumice and a lava dome define a pre-climactic magmatic stage of ~0.7 Myr duration prior to the climactic eruption and formation of the eponymous caldera. A further 0.4 Myr of post-climactic zircon crystallization is recorded in lava domes and cogenetic granodiorite clasts. Zircon crystallization is recorded for approximately 1.3 Myr for the Chuhuilla cycle; however the record is entirely pre-climactic. We propose a model for the Pastos Grandes cycle in which the climactic caldera-forming eruption vented the upper portions of the reservoir that were zircon saturated. Subsequently, deeper “remnant” dacite magma previously outside the zone of zircon saturation but crystallizing other major phases, rose to re-establish lithostatic equilibrium, commenced zircon crystallization anew, and drove resurgent volcanism and uplift. This ~1.1 Myr zircon crystallization history records the minimum duration of the lifetime of the PGI supereruption magma from its accumulation to post-climactic solidification. These data support >1 Myr magma lifetimes and a link between volcanic and plutonic realms in large sub-caldera magma reservoirs in the uppermost crust that feed some supereruptions. Title: Understanding large resurgent calderas and associated magma systems : the Pastos Grandes Caldera Complex, southwest Bolivia Author: Kaiser, Jason Frederick, 1985- The Pastos Grandes Caldera Complex (PGCC) in southwest Bolivia has produced two large-volume (≥800 km³ DRE) dacite ignimbrites from a nested caldera source over a period of 5.5 Myr. In addition to the large-volume ignimbrites, a small-volume ignimbrite shield and post-climactic lavas define this composite system. Based on detailed field work and analysis of satellite imagery plus biotite ⁴⁰Ar/³⁹Ar dating, we summarize a revised stratigraphy, areal distribution and volume calculations for ignimbrites. From interpretations of stratigraphy and structures along the caldera margins, we propose an asymmetric collapse hinged along the north and western boundaries. Both the early Chuhuilla (5.45 ± 0.02 Ma), and the younger Pastos Grandes (2.89 ± 0.01 Ma) calderas share the hinge and much of the eastern collapse scarp, however the Chuhuilla caldera defines a much larger area (>1700 km²) compared to the Pastos Grandes (870 km²). It is proposed here that pre-existing regional tectonic weaknesses combined with influences of the magma body caused roof failure and caldera collapse. The vast majority of the ignimbrite volume lies within the Chuhuilla and Pastos Grandes calderas (92 and 75% respectively). Considerable intracaldera fill and the lack of preceding plinian deposits suggest that the caldera collapse was early and the eruptive column was not high and was short-lived. The physical properties of the ignimbrites, the limit of their areal distribution to regional topographic lows along with paleomagnetic characteristics support the idea of dense sluggish pyroclastic flows. New volume calculations using multiple methods update previous estimates, with the Chuhuilla now at approximately 1300 km³ and the Pastos Grandes at 800 km³. The ignimbrite volumes and spatial pattern of vents suggest that the caldera complex mirrors the construction of a long-lived composite batholith that focused spatially with time. Eruptions from the PGCC have produced compositionally restricted, high-K dacites with volumetrically minor rhyolites. Combined with granodiorite xenoliths, each caldera cycle contains a progression of textural maturity from ignimbrite, through post-climactic lavas, to remnant pluton. The chemical signatures in the PGCC mirror those of the host Altiplano Puna Volcanic Complex (APVC) and resemble typical arc characteristics (i.e. LIL enriched magmas - Ba/Nb of 4.7-4.8 and Ba/La of 1.6-2.0). However, overprinted on the arc signature are elevated radiogenic isotopes (⁸⁷Sr/⁸⁶Sr ~0.708 - 0.709), which suggest high degrees of crustal assimilation that is thought to be related to increased mantle input from melted asthenosphere. It is suggested here that a combination of assimilation and fractional crystallization from the regional mid-crustal parental source would create the magmas erupted in the PGCC. Subtle decreases in the ⁸⁷Sr/⁸⁶Sr from the Chuhuilla caldera cycle, to the younger Pastos Grandes cycle suggest higher amounts of crustal assimilation related to more heat flow during the peak of the flare up. Zircon chronochemistry reveals that the climactic, caldera-forming eruptions of the PGCC punctuate the protracted magma accumulation and storage periods. The combination of in-situ zircon U-Pb ages with indicators for geochemical evolution (e.g., Zr/Hf, Yb/Gd, Eu/Eu*, Th, U) magmatic temperatures (e.g., Ti) in zircon, reveals protracted magma presence before and after the climactic 2.89 ± 0.01 Ma Pastos Grandes Ignimbrite (PGI) supereruption (~800 km³ of magma) in southwest Bolivia. Zircons from PGI pumice and a lava dome define a pre-climactic magmatic stage of ~0.7 Myr duration prior to the climactic eruption and formation of the eponymous caldera. A further 0.4 Myr of post-climactic zircon crystallization is recorded in lava domes and cogenetic granodiorite clasts. Zircon crystallization is recorded for approximately 1.3 Myr for the Chuhuilla cycle; however the record is entirely pre-climactic. We propose a model for the Pastos Grandes cycle in which the climactic caldera-forming eruption vented the upper portions of the reservoir that were zircon saturated. Subsequently, deeper “remnant” dacite magma previously outside the zone of zircon saturation but crystallizing other major phases, rose to re-establish lithostatic equilibrium, commenced zircon crystallization anew, and drove resurgent volcanism and uplift. This ~1.1 Myr zircon crystallization history records the minimum duration of the lifetime of the PGI supereruption magma from its accumulation to post-climactic solidification. These data support >1 Myr magma lifetimes and a link between volcanic and plutonic realms in large sub-caldera magma reservoirs in the uppermost crust that feed some supereruptions. Close

• 13108. [Article] All hosts are not created equal : variation in amphibian responses to an emerging fungal pathogen and why it matters

  Emerging infectious diseases are increasing globally and are a threat to human, wildlife, and ecosystem health. The emerging fungal pathogen, Batrachochytrium dendrobatidis (Bd), or amphibian chytrid fungus, ...

  Citation × Citation Citation Abstract Copy Title: All hosts are not created equal : variation in amphibian responses to an emerging fungal pathogen and why it matters Author: Gervasi, Stephanie S. Emerging infectious diseases are increasing globally and are a threat to human, wildlife, and ecosystem health. The emerging fungal pathogen, Batrachochytrium dendrobatidis (Bd), or amphibian chytrid fungus, is associated with worldwide amphibian population declines and extinctions. Bd has been found on every continent where amphibians exist and has been documented to infect hundreds of species. As with other multi-host pathogens, the outcome of infection with Bd appears to vary among individuals, species, and populations. Variation in host responses to infection can lead to changes in the structure and composition of amphibian assemblages and can affect disease dynamics including pathogen persistence or fadeouts in ecological communities. Understanding the feedback between hosts and pathogens requires disentangling the influence of multiple interacting biotic and abiotic factors, yet fundamentally depends on characterizing intrinsic host responses to infection. This thesis broadly examines variation in species-specific susceptibility to the chytrid fungus among amphibians. I have characterized patterns of mortality, quantitative infection load, feeding behavior, and pathogen avoidance behavior of twenty different amphibian species exposed to the fungus or control conditions (Chapter 2). We found a high degree of variation in pathogen-induced responses to chytrid fungus, ranging from zero mortality to 100% mortality after only six days of pathogen exposure. Variation in infection load was also significant at the species level and there was not always a direct relationship between infection load and mortality. Behavior of pathogen exposed animals was significantly different from that of control animals, and reduced feeding behavior of pathogen-exposed animals is likely to be related to the decline in health of pathogen-exposed animals. In Chapter 3, I examined a special case of amphibian susceptibility to chytrid fungus in the American bullfrog (Lithobates catesbeianus). Bullfrogs are widely reported to be a tolerant host and a carrier of Bd that spreads the pathogen to less tolerant hosts. However, this hypothesis has not been rigorously tested using an experimental approach. In Chapter 3, co-authors and I tested whether bullfrogs raised from eggs to metamorphosis in outdoor mesocosms were susceptible to two different strains of Bd (one strain isolated from a "non susceptible" species, the American bullfrog; the second strain isolated from a highly susceptible species, the Western toad (Anaxyrus boreas)). Bullfrogs were susceptible to strain JEL 274, and this is the first documented case of susceptibility to chytrid fungus in this species. Bullfrogs were not susceptible to strain JEL 630, indicating variation in virulence among chytrid fungus strains and important context dependency when considering the effect of infection non individuals, species, and populations of amphibians. In Chapter 4, I examined fine- scale variation in responses of three key amphibian hosts, and examine the evidence for tolerance (the ability to maintain health as infection severity increases) or resistance (the ability to reduce pathogen infection load) of larval and post-metamorphic animals to Bd. I saw pronounced variation in responses to chytrid fungus among species, between life history stages, over time, and found that responses to the fungal inoculate were not dose dependent in two out of the three species examined. In the final data chapter, Chapter 5, I investigated immunological responses that underlie variation in species-specific responses to Bd. I looked at temporal patterns of functional immune responses during a time-course of early and later stage exposure to Bd, spanning 24 hours after experimental inoculation to 15 days post-inoculation. I uncovered patterns in immune responses that were distinctly associated with susceptibility and temporal patterns in infection load associated with susceptibility and immune response. This thesis provides critical information about variation in host responses to a conservation relevant pathogen. Differences in how host hosts acquire, transmit, and persist with infection have important implications for spatiotemporal disease dynamics. Further, understanding host sensitivity to infection allows for predictive risk management of imperiled species. Title: All hosts are not created equal : variation in amphibian responses to an emerging fungal pathogen and why it matters Author: Gervasi, Stephanie S. Emerging infectious diseases are increasing globally and are a threat to human, wildlife, and ecosystem health. The emerging fungal pathogen, Batrachochytrium dendrobatidis (Bd), or amphibian chytrid fungus, is associated with worldwide amphibian population declines and extinctions. Bd has been found on every continent where amphibians exist and has been documented to infect hundreds of species. As with other multi-host pathogens, the outcome of infection with Bd appears to vary among individuals, species, and populations. Variation in host responses to infection can lead to changes in the structure and composition of amphibian assemblages and can affect disease dynamics including pathogen persistence or fadeouts in ecological communities. Understanding the feedback between hosts and pathogens requires disentangling the influence of multiple interacting biotic and abiotic factors, yet fundamentally depends on characterizing intrinsic host responses to infection. This thesis broadly examines variation in species-specific susceptibility to the chytrid fungus among amphibians. I have characterized patterns of mortality, quantitative infection load, feeding behavior, and pathogen avoidance behavior of twenty different amphibian species exposed to the fungus or control conditions (Chapter 2). We found a high degree of variation in pathogen-induced responses to chytrid fungus, ranging from zero mortality to 100% mortality after only six days of pathogen exposure. Variation in infection load was also significant at the species level and there was not always a direct relationship between infection load and mortality. Behavior of pathogen exposed animals was significantly different from that of control animals, and reduced feeding behavior of pathogen-exposed animals is likely to be related to the decline in health of pathogen-exposed animals. In Chapter 3, I examined a special case of amphibian susceptibility to chytrid fungus in the American bullfrog (Lithobates catesbeianus). Bullfrogs are widely reported to be a tolerant host and a carrier of Bd that spreads the pathogen to less tolerant hosts. However, this hypothesis has not been rigorously tested using an experimental approach. In Chapter 3, co-authors and I tested whether bullfrogs raised from eggs to metamorphosis in outdoor mesocosms were susceptible to two different strains of Bd (one strain isolated from a "non susceptible" species, the American bullfrog; the second strain isolated from a highly susceptible species, the Western toad (Anaxyrus boreas)). Bullfrogs were susceptible to strain JEL 274, and this is the first documented case of susceptibility to chytrid fungus in this species. Bullfrogs were not susceptible to strain JEL 630, indicating variation in virulence among chytrid fungus strains and important context dependency when considering the effect of infection non individuals, species, and populations of amphibians. In Chapter 4, I examined fine- scale variation in responses of three key amphibian hosts, and examine the evidence for tolerance (the ability to maintain health as infection severity increases) or resistance (the ability to reduce pathogen infection load) of larval and post-metamorphic animals to Bd. I saw pronounced variation in responses to chytrid fungus among species, between life history stages, over time, and found that responses to the fungal inoculate were not dose dependent in two out of the three species examined. In the final data chapter, Chapter 5, I investigated immunological responses that underlie variation in species-specific responses to Bd. I looked at temporal patterns of functional immune responses during a time-course of early and later stage exposure to Bd, spanning 24 hours after experimental inoculation to 15 days post-inoculation. I uncovered patterns in immune responses that were distinctly associated with susceptibility and temporal patterns in infection load associated with susceptibility and immune response. This thesis provides critical information about variation in host responses to a conservation relevant pathogen. Differences in how host hosts acquire, transmit, and persist with infection have important implications for spatiotemporal disease dynamics. Further, understanding host sensitivity to infection allows for predictive risk management of imperiled species. Close

• 13109. [Article] The Anatomy of a Buried Submarine Hydrothermal System, Clark Volcano, Kermadec Arc, New Zealand

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the Society ...

  Citation × Citation Citation Abstract Copy Title: The Anatomy of a Buried Submarine Hydrothermal System, Clark Volcano, Kermadec Arc, New Zealand Author: Ditchburn, R. G., Walker, S. L., et al., Merle, S. G., de Ronde, C. E. J. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the Society of Economic Geologists and can be found at: http://economicgeology.org/. Title: The Anatomy of a Buried Submarine Hydrothermal System, Clark Volcano, Kermadec Arc, New Zealand Author: Ditchburn, R. G., Walker, S. L., et al., Merle, S. G., de Ronde, C. E. J. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by the Society of Economic Geologists and can be found at: http://economicgeology.org/. Close

• 13110. [Article] Incubation patterns, parental roles, and nest survival of black oystercatchers (Haematopus bachmani) : influences of environmental processes and potential disturbance stimuli

  Shorebirds display great variation in mating systems and breed in dynamic environments that are increasingly subject to human threats worldwide. In order to adequately assess productivity and demography ...

  Citation × Citation Citation Abstract Copy Title: Incubation patterns, parental roles, and nest survival of black oystercatchers (Haematopus bachmani) : influences of environmental processes and potential disturbance stimuli Author: Spiegel, Caleb S. Shorebirds display great variation in mating systems and breed in dynamic environments that are increasingly subject to human threats worldwide. In order to adequately assess productivity and demography of shorebird populations, it is important to understand factors that influence patterns of parental care and reproductive success. The Black Oystercatcher (Haematopus bachmani) is a shorebird species of concern and an indicator of the health of intertidal ecosystems. Much information on breeding biology is lacking for the species, though it is reported to regularly experience low reproductive success and may be vulnerable to human disturbance during nesting. This thesis examines relationships among natural and human processes related to incubation and nest success of Black Oystercatchers in a high density breeding area of Alaska, experiencing increasing human recreational activity. In 2005 and 2006, oystercatcher nests were continuously monitored with video cameras to investigate the association of cyclical (time of day, tide, ambient temperature, seasonality) and stochastic (natural/human disturbance) processes with incubation patterns (nest attendance, incubation bout length, incubation recess rate) and sex roles. Review of over 3,000 hours of footage from 13 molecularly sexed nesting pairs revealed complimentary bi-parental care with differing roles between sexes. Females allocated more to nest attendance and had longer incubation bout lengths, indicating a greater investment in incubation compared to males. Males responded more frequently to nest area disturbance stimuli compared to females, indicating that males invest more in nest defense. Incubation patterns were also influenced by tide stage and height, ambient temperature, and disturbance stimuli. Incubation bout lengths nearly doubled at night, independent of sex. Longer nocturnal bouts may minimize parental activity near the nest during periods of increased predation risk when incubation duty changes could reveal the presence of nests to nocturnal predators. Video footage was also used to document the types and frequencies of human and predator stimuli, and extreme weather and tide episodes encountered near oystercatcher nests, and the effect of these potential disturbance stimuli on incubation behavior and nest success. Nearly 800 potential disturbance stimulus events were documented within 25 m of video monitored nests. Other bird species were the most frequently observed type of potential disturbance, but were largely ignored by incubating oystercatchers. Oystercatchers were most frequently disturbed (as evidenced by displacement from a nest) by conspecifics and humans, with nests left unattended for longer periods following human disturbance than any other disturbance type. Although infrequent, a high proportion of mammal observations also resulted in oystercatchers flushing from their nests. Changes in incubation behavior due to disturbance were not found to affect nest success, nor did nest success decrease with proximity to areas of frequent human recreational activity. Nocturnal nest predation by mustelids and nighttime flood tides accounted for six of seven nest failures recorded on video, even though nights were disproportionately short during the study. Thus, future shorebird breeding studies should assess causes of nest failure from latent nocturnal causes, rather than just obvious diurnal causes. With the analysis of extensive nest observation data this study identified natural and anthropogenic processes that affected incubation patterns of an uncommon shorebird species, specially adapted to a dynamic nesting environment. Results elucidate factors influencing oystercatcher life history and lay the groundwork for further investigation into the effects of human disturbance on nest success and demography of the Black Oystercatcher. Future research should investigate nest success in breeding areas experiencing higher levels of disturbance, include post-hatching breeding stages, and be conducted over multiple breeding seasons. Title: Incubation patterns, parental roles, and nest survival of black oystercatchers (Haematopus bachmani) : influences of environmental processes and potential disturbance stimuli Author: Spiegel, Caleb S. Shorebirds display great variation in mating systems and breed in dynamic environments that are increasingly subject to human threats worldwide. In order to adequately assess productivity and demography of shorebird populations, it is important to understand factors that influence patterns of parental care and reproductive success. The Black Oystercatcher (Haematopus bachmani) is a shorebird species of concern and an indicator of the health of intertidal ecosystems. Much information on breeding biology is lacking for the species, though it is reported to regularly experience low reproductive success and may be vulnerable to human disturbance during nesting. This thesis examines relationships among natural and human processes related to incubation and nest success of Black Oystercatchers in a high density breeding area of Alaska, experiencing increasing human recreational activity. In 2005 and 2006, oystercatcher nests were continuously monitored with video cameras to investigate the association of cyclical (time of day, tide, ambient temperature, seasonality) and stochastic (natural/human disturbance) processes with incubation patterns (nest attendance, incubation bout length, incubation recess rate) and sex roles. Review of over 3,000 hours of footage from 13 molecularly sexed nesting pairs revealed complimentary bi-parental care with differing roles between sexes. Females allocated more to nest attendance and had longer incubation bout lengths, indicating a greater investment in incubation compared to males. Males responded more frequently to nest area disturbance stimuli compared to females, indicating that males invest more in nest defense. Incubation patterns were also influenced by tide stage and height, ambient temperature, and disturbance stimuli. Incubation bout lengths nearly doubled at night, independent of sex. Longer nocturnal bouts may minimize parental activity near the nest during periods of increased predation risk when incubation duty changes could reveal the presence of nests to nocturnal predators. Video footage was also used to document the types and frequencies of human and predator stimuli, and extreme weather and tide episodes encountered near oystercatcher nests, and the effect of these potential disturbance stimuli on incubation behavior and nest success. Nearly 800 potential disturbance stimulus events were documented within 25 m of video monitored nests. Other bird species were the most frequently observed type of potential disturbance, but were largely ignored by incubating oystercatchers. Oystercatchers were most frequently disturbed (as evidenced by displacement from a nest) by conspecifics and humans, with nests left unattended for longer periods following human disturbance than any other disturbance type. Although infrequent, a high proportion of mammal observations also resulted in oystercatchers flushing from their nests. Changes in incubation behavior due to disturbance were not found to affect nest success, nor did nest success decrease with proximity to areas of frequent human recreational activity. Nocturnal nest predation by mustelids and nighttime flood tides accounted for six of seven nest failures recorded on video, even though nights were disproportionately short during the study. Thus, future shorebird breeding studies should assess causes of nest failure from latent nocturnal causes, rather than just obvious diurnal causes. With the analysis of extensive nest observation data this study identified natural and anthropogenic processes that affected incubation patterns of an uncommon shorebird species, specially adapted to a dynamic nesting environment. Results elucidate factors influencing oystercatcher life history and lay the groundwork for further investigation into the effects of human disturbance on nest success and demography of the Black Oystercatcher. Future research should investigate nest success in breeding areas experiencing higher levels of disturbance, include post-hatching breeding stages, and be conducted over multiple breeding seasons. Close

• 13111. [Article] Population characteristics and movement patterns of redband trout (Oncorhynchus mykiss) and mountain whitefish (Prosopium williamsoni) in the Crooked River, Oregon

  Over the last decade, the Oregon Department of Fish and Wildlife (ODFW) has documented a precipitous decline in the Crooked River redband trout (Oncorhynchus mykiss) population, prompting this study to ...

  Citation × Citation Citation Abstract Copy Title: Population characteristics and movement patterns of redband trout (Oncorhynchus mykiss) and mountain whitefish (Prosopium williamsoni) in the Crooked River, Oregon Author: Nesbit, Shivonne M. Over the last decade, the Oregon Department of Fish and Wildlife (ODFW) has documented a precipitous decline in the Crooked River redband trout (Oncorhynchus mykiss) population, prompting this study to address potential factors contributing to the decline. There are two main goals to this project: (1) identify potential factors contributing to the reduction of the redband trout population in the Crooked River fishery and (2) provide management recommendations to all of the agencies responsible for managing the Crooked River that might effect a change in the redband trout population trend. This thesis had three objectives: (1) evaluate the movement patterns of redband trout and mountain whitefish in the Crooked River below Bowman Dam, (2) monitor total dissolved gas levels (TDG) in the Crooked River to evaluate the incidence of supersaturated water and gas bubble disease in redband trout and mountain whitefish and (3) implement a more comprehensive population estimate survey to document both redband trout and mountain whitefish population densities. Prior to this study, limited data existed on the distribution and movement patterns of redband trout and mountain whitefish in the Crooked River below Bowman Dam. Based on the results from the 2-year telemetry study, redband trout and mountain whitefish population exhibit a resident life history strategy and stay in the Wild and Scenic Section of the Crooked River below Bowman Dam. Two potential explanations for the observed population decline were plausible: the decline was actually a decline, or the fish moved to other sections of the Crooked River downstream of Bowman Dam. The telemetery study showed that redband trout and mountain whitefish stay within this section of river, thereby providing evidence against the explanation that the observed population decline was a result of movement of fish to other sections of river. The total dissolved gas study demonstrated that gas saturation levels become elevated enough to cause gas bubble disease in the Crooked River below Bowman Dam. The gas saturation in the Crooked River is equivalent or higher than levels shown to produce gas bubble disease (GBD) in fishes. When flows exceed 600 cfs, the total dissolved gas saturation exceeds the maximum Oregon Department of Environmental Quality mandated level of 110% gas saturation in the Crooked River. Flows in excess of 600cfs are common during spring runoff events below Bowman Dam. From 1989-2009, flows exceeded 600 cfs in 13 of the 21 years and 1000 cfs in 10 of the 21 years. The past population effects of high flows and supersaturated waters on redband trout and mountain whitefish are difficult to quantify, but based on the hydrograph and the saturation curve, the years when gas bubble disease might have been present in fish can be predicted. Given the strong linear relationship between TDG and stream average daily discharge (r2 = 0.93), discharge itself can be used as a predictive tool for assessing TDG levels in the river. Based on the flow data from the USBOR gauging station and the gas saturation curve for the wild and scenic section of the Crooked River generated here, gas bubble disease was probably present in fish in 1993, 1996, 1997, 1998, 1999, and 2004. The redband trout population density has varied considerably from year to year, with a peak observed in 1994 and the lowest point observed in 2006. A large increase in the number of redband trout per km occurred between 1993 and 1994, indicating that the density of fish can increase substantially in one year. The decline in redband trout density from 1994 to 2006 appears to be more gradual than the increase in density observed from 1993 to 1994. Since 2006, the redband trout population density appears to be increasing based on qualitative patterns. One interesting finding was that in 2007, the mountain whitefish density was estimated to be 7 times greater than the redband trout population, in 2008 it was estimated to be 4 times greater, but in 2009, the mountain whitefish density was only marginally higher than the redband trout population. In the three years of this study, there appears to be a shift in the relative abundance of redband trout and mountain whitefish directly below Bowman Dam. The reduction in the mountain whitefish population density from 2007 to 2008 was not expected based on angler accounts of the increase in mountain whitefish population densities. Title: Population characteristics and movement patterns of redband trout (Oncorhynchus mykiss) and mountain whitefish (Prosopium williamsoni) in the Crooked River, Oregon Author: Nesbit, Shivonne M. Over the last decade, the Oregon Department of Fish and Wildlife (ODFW) has documented a precipitous decline in the Crooked River redband trout (Oncorhynchus mykiss) population, prompting this study to address potential factors contributing to the decline. There are two main goals to this project: (1) identify potential factors contributing to the reduction of the redband trout population in the Crooked River fishery and (2) provide management recommendations to all of the agencies responsible for managing the Crooked River that might effect a change in the redband trout population trend. This thesis had three objectives: (1) evaluate the movement patterns of redband trout and mountain whitefish in the Crooked River below Bowman Dam, (2) monitor total dissolved gas levels (TDG) in the Crooked River to evaluate the incidence of supersaturated water and gas bubble disease in redband trout and mountain whitefish and (3) implement a more comprehensive population estimate survey to document both redband trout and mountain whitefish population densities. Prior to this study, limited data existed on the distribution and movement patterns of redband trout and mountain whitefish in the Crooked River below Bowman Dam. Based on the results from the 2-year telemetry study, redband trout and mountain whitefish population exhibit a resident life history strategy and stay in the Wild and Scenic Section of the Crooked River below Bowman Dam. Two potential explanations for the observed population decline were plausible: the decline was actually a decline, or the fish moved to other sections of the Crooked River downstream of Bowman Dam. The telemetery study showed that redband trout and mountain whitefish stay within this section of river, thereby providing evidence against the explanation that the observed population decline was a result of movement of fish to other sections of river. The total dissolved gas study demonstrated that gas saturation levels become elevated enough to cause gas bubble disease in the Crooked River below Bowman Dam. The gas saturation in the Crooked River is equivalent or higher than levels shown to produce gas bubble disease (GBD) in fishes. When flows exceed 600 cfs, the total dissolved gas saturation exceeds the maximum Oregon Department of Environmental Quality mandated level of 110% gas saturation in the Crooked River. Flows in excess of 600cfs are common during spring runoff events below Bowman Dam. From 1989-2009, flows exceeded 600 cfs in 13 of the 21 years and 1000 cfs in 10 of the 21 years. The past population effects of high flows and supersaturated waters on redband trout and mountain whitefish are difficult to quantify, but based on the hydrograph and the saturation curve, the years when gas bubble disease might have been present in fish can be predicted. Given the strong linear relationship between TDG and stream average daily discharge (r2 = 0.93), discharge itself can be used as a predictive tool for assessing TDG levels in the river. Based on the flow data from the USBOR gauging station and the gas saturation curve for the wild and scenic section of the Crooked River generated here, gas bubble disease was probably present in fish in 1993, 1996, 1997, 1998, 1999, and 2004. The redband trout population density has varied considerably from year to year, with a peak observed in 1994 and the lowest point observed in 2006. A large increase in the number of redband trout per km occurred between 1993 and 1994, indicating that the density of fish can increase substantially in one year. The decline in redband trout density from 1994 to 2006 appears to be more gradual than the increase in density observed from 1993 to 1994. Since 2006, the redband trout population density appears to be increasing based on qualitative patterns. One interesting finding was that in 2007, the mountain whitefish density was estimated to be 7 times greater than the redband trout population, in 2008 it was estimated to be 4 times greater, but in 2009, the mountain whitefish density was only marginally higher than the redband trout population. In the three years of this study, there appears to be a shift in the relative abundance of redband trout and mountain whitefish directly below Bowman Dam. The reduction in the mountain whitefish population density from 2007 to 2008 was not expected based on angler accounts of the increase in mountain whitefish population densities. Close

• 13112. [Article] Some aspects of the comparative ecology of fishes associated with juvenile sockeye salmon, Oncorhynchus nerka (Walbaum), in the lakes of the Naknek river system, Alaska

  A study of the distribution, relative abundance and diet of fishes sympatric with juvenile sockeye salmon, Oncorhynchus nerka (Walbaum), within the freshwater nursery areas of the Naknek River system was ...

  Citation × Citation Citation Abstract Copy Title: Some aspects of the comparative ecology of fishes associated with juvenile sockeye salmon, Oncorhynchus nerka (Walbaum), in the lakes of the Naknek river system, Alaska Author: Wallace, Richard L. A study of the distribution, relative abundance and diet of fishes sympatric with juvenile sockeye salmon, Oncorhynchus nerka (Walbaum), within the freshwater nursery areas of the Naknek River system was undertaken from 1961 to 1963. The study was part of an extensive investigation to determine what factors in the freshwater environment were limiting the size of the populations of sockeye salmon returning to the rivers of Bristol Bay, Alaska. The speties found associated with juvenile salmon in the limnetic zones of the Naknek system were the pond smelt, Hypomesus olidus (Pallas); the least cisco, Coregonus sardinella Valenciennes; the threespine stickleback, Gasterosteus aculeatus Linnaeus; and the ninespine stickleback, Pungitius pungitius (Linnaeus). Life history information was collected for these sympatric species. Tow nets were used to capture samples of fish from the limnetic portions of the nursery areas. Some samples were collected by beach seines, lake traps and otter trawls. Plankton samples were collected and compared to the diets of the limnetic fishes. Although some confusion has existed in the literature, I concluded that pond smelt of the Naknek system belong to Hypomesus olidus (Pallas). The populations of smelt were comprised of six age-groups in the late summer, but most specimens belonged to three age-groups. Most members of the species spawn in the spring of the fourth year of life. The estimated fecundity ranged from 900 to 4,300 eggs per female. Seven age-groups of least ciscoes were present in the populations of the Naknek system. The species in the Naknek system probably spawned for the first time in the fall of their fourth year. The estimated fecundity of two specimens was 4,006 and 14,380 eggs. Populations of three spine stickleback were comprised of three age-groups of fish. I was unable to assign ages to ninespine stickleback. Estimates of the fecundity of the species ranged from 116 to 456 eggs per female. All species studied were distributed throughout the Naknek system. The relative abundance of the fishes studied was variable between and within nursery areas and from year to year. The population densities of pond smelt and threespine stickleback were larger in the surface waters compared to the deep waters. The relative abundance of sockeye fry, yearlings and ninespine stickleback was greater in the surface stratum rather than the deep stratum in most nursery areas. The five main food items utilized by these limnetic species were cladocerans (Bosmina sp. and Daphnia sp.); copepods (cyclopoid copepods and Diaptomus sp.); and Dipteran insects. Analysis of the similarity of diets indicated that the diets of sockeye fry and pond smelt were more similar than were the diets of sockeye fry or yearlings and any other sympatric species. The diet of sockeye fry was more similar to that of either species of stickleback than was the diet of sockeye yearlings. An analysis of the food of various sizes of each species of fish indicated the diets of three age-groups of smelt were more similar than the diets of various age-groups of any other fish. The food composition of three age-groups of ciscoes and two size groups of both species of stickleback showed a strong positive correlation. The diets of sockeye fry and yearlings showed the weakest positive correlation of the species studied. All species of fish studied selectively fed on one or more components of the zooplankton. Daphnia sp. and cyclopoid copepods were strongly selected in Lake Coville. Cyclopoids were selected in South Bay. Bosmina sp. was selected from the waters of West End. In Lake Coville, the greatest potential competition for food probably existed between the large populations of pond smelt and sockeye fry. In the West End nursery area, potential competition between juvenile salmon and both species of stickleback may not be severe, depending on the age composition of the salmon population present in the nursery area. The possibility exists that the relatively low numbers of adult sockeye salmon returning to the comparatively rich lakes of the Naknek River system is due to the presence of large populations of sympatric species of fish. Each of these sympatric species feed on the same general types of food organisms as do the juvenile salmon and may affect the numbers of young salmon that leave the lake, and subsequently return from the ocean. Title: Some aspects of the comparative ecology of fishes associated with juvenile sockeye salmon, Oncorhynchus nerka (Walbaum), in the lakes of the Naknek river system, Alaska Author: Wallace, Richard L. A study of the distribution, relative abundance and diet of fishes sympatric with juvenile sockeye salmon, Oncorhynchus nerka (Walbaum), within the freshwater nursery areas of the Naknek River system was undertaken from 1961 to 1963. The study was part of an extensive investigation to determine what factors in the freshwater environment were limiting the size of the populations of sockeye salmon returning to the rivers of Bristol Bay, Alaska. The speties found associated with juvenile salmon in the limnetic zones of the Naknek system were the pond smelt, Hypomesus olidus (Pallas); the least cisco, Coregonus sardinella Valenciennes; the threespine stickleback, Gasterosteus aculeatus Linnaeus; and the ninespine stickleback, Pungitius pungitius (Linnaeus). Life history information was collected for these sympatric species. Tow nets were used to capture samples of fish from the limnetic portions of the nursery areas. Some samples were collected by beach seines, lake traps and otter trawls. Plankton samples were collected and compared to the diets of the limnetic fishes. Although some confusion has existed in the literature, I concluded that pond smelt of the Naknek system belong to Hypomesus olidus (Pallas). The populations of smelt were comprised of six age-groups in the late summer, but most specimens belonged to three age-groups. Most members of the species spawn in the spring of the fourth year of life. The estimated fecundity ranged from 900 to 4,300 eggs per female. Seven age-groups of least ciscoes were present in the populations of the Naknek system. The species in the Naknek system probably spawned for the first time in the fall of their fourth year. The estimated fecundity of two specimens was 4,006 and 14,380 eggs. Populations of three spine stickleback were comprised of three age-groups of fish. I was unable to assign ages to ninespine stickleback. Estimates of the fecundity of the species ranged from 116 to 456 eggs per female. All species studied were distributed throughout the Naknek system. The relative abundance of the fishes studied was variable between and within nursery areas and from year to year. The population densities of pond smelt and threespine stickleback were larger in the surface waters compared to the deep waters. The relative abundance of sockeye fry, yearlings and ninespine stickleback was greater in the surface stratum rather than the deep stratum in most nursery areas. The five main food items utilized by these limnetic species were cladocerans (Bosmina sp. and Daphnia sp.); copepods (cyclopoid copepods and Diaptomus sp.); and Dipteran insects. Analysis of the similarity of diets indicated that the diets of sockeye fry and pond smelt were more similar than were the diets of sockeye fry or yearlings and any other sympatric species. The diet of sockeye fry was more similar to that of either species of stickleback than was the diet of sockeye yearlings. An analysis of the food of various sizes of each species of fish indicated the diets of three age-groups of smelt were more similar than the diets of various age-groups of any other fish. The food composition of three age-groups of ciscoes and two size groups of both species of stickleback showed a strong positive correlation. The diets of sockeye fry and yearlings showed the weakest positive correlation of the species studied. All species of fish studied selectively fed on one or more components of the zooplankton. Daphnia sp. and cyclopoid copepods were strongly selected in Lake Coville. Cyclopoids were selected in South Bay. Bosmina sp. was selected from the waters of West End. In Lake Coville, the greatest potential competition for food probably existed between the large populations of pond smelt and sockeye fry. In the West End nursery area, potential competition between juvenile salmon and both species of stickleback may not be severe, depending on the age composition of the salmon population present in the nursery area. The possibility exists that the relatively low numbers of adult sockeye salmon returning to the comparatively rich lakes of the Naknek River system is due to the presence of large populations of sympatric species of fish. Each of these sympatric species feed on the same general types of food organisms as do the juvenile salmon and may affect the numbers of young salmon that leave the lake, and subsequently return from the ocean. Close

• 13113. [Article] Health Insurance Exchanges

  Examining committee: Colleen Chrisinger

  Citation × Citation Citation Abstract Copy Title: Health Insurance Exchanges Author: Fracchia, Elena, Hall, Tiffany, Remer, Matthew, Saxe, Karen, Wu, Wei-Ting Year: 2011 Examining committee: Colleen Chrisinger Title: Health Insurance Exchanges Author: Fracchia, Elena, Hall, Tiffany, Remer, Matthew, Saxe, Karen, Wu, Wei-Ting Year: 2011 Examining committee: Colleen Chrisinger Close

• 13114. [Article] The biology and pathogenicity of a sheath nematode Hemicycliophora similis Thorne, 1955

  A study, using greenhouse and laboratory experiments, was made of Hemicycliophora similis from Bandon, Oregon to determine: identity and morphometrics, time and development of a life cycle, host plant ...

  Citation × Citation Citation Abstract Copy Title: The biology and pathogenicity of a sheath nematode Hemicycliophora similis Thorne, 1955 Author: McKewan, Jeanette Anne A study, using greenhouse and laboratory experiments, was made of Hemicycliophora similis from Bandon, Oregon to determine: identity and morphometrics, time and development of a life cycle, host plant preferences and optimum environmental conditions for reproduction and pathogenicity. Morphometric investigations revealed discrepancies between the measurements of this nematode species and those recorded in nematological literature for H. similis. Personal communications with R. P. Esser, H. J. Jensen and B. M. Zuckerman suggested the variations noted do not necessitate describing a new species. For purposes of this research the nematode is named Hemicycliophora sirnilis. Life history investigations were conducted to determine the number of days required to complete a life cycle and the various stages as the nematode developed from egg to egg. Eggs mature to first-stage larvae, without sheath or spear, in 3-5 days and hatch as second-stage larvae in 8-10 days. Second-stage larvae inoculated onto carrot seedlings matured into third-stage larvae in 12-15 days. Fourth-stage larvae appeared in 25-28 days, and adults were present in 35-38 days. Embryonating eggs were observed lodged within an incompletely shed fourth-stage cuticle attached to adult females and within the normal sheath surrounding the adult. One molting specimen was found with two eggs lodged within the fourth-stage cuticle. Such eggs were seen to develop to second-stage larvae; however, none were observed over a long enough time period to determine if larvae hatched and emerged free of the cuticular confinement. Evaluated as hosts were beet, broccoli, carrot, corn, dill, pea, radish, rutabaga, tomato and turnip. Carrot, tomato and turnip supported the highest increase in population; no substantial increase was observed on beet, broccoli, corn and dill. The nematode formed galls consisting of large multibranched growths and reproduced on many of the plant species tested. Galling of seedling roots was most severe on carrot, but slight galling was observed on beet, rutabaga and turnip. Multibranching was observed with varying severity in all hosts. Germination of carrot seeds was reduced substantially when grown in sandy soil infested with H. similis. Slight germination reductions occurred with all hosts tested except corn and pea. Adults and larvae were observed feeding behind root tips and on nematode induced galls. Root discoloration was noted on several plants. To evaluate temperature and soil optima, rooted cranberry cuttings, germinated cranberry seedlings and carrot seedlings were utilized. Carrot seeds were planted in sandy soils of two different textures and pH, infested with H. similis and grown in three temperature regimes: 30°C and 24°C night, 22°C day and 14°C night and 30°C day 6 °C night. The optimum temperature for reproduction on carrot was 22°C day 14°C night in both soil types. A pH gradient developed in cups with the least acidic pH occurring at the base corresponding to maximum nutrient uptake by plant roots. The soil mix in which bog sand from Bandon was incorporated developed a more acidic condition presumably due to the additional organic N content which supplied ammonical nitrogen. The soil mix with Newport sand had no additional organic N and a less acidic condition developed. Maximum nematode population and root density also occurred at the base of the cup. Plants grown in infested soil had sparse multibranched roots; no galls were observed in this experiment. Cranberry cuttings were grown in sterile bog soil from Bandon, Oregon and inoculated with 225 nematodes/450 cc soil. The optimum temperature for nematode reproduction and plant growth was 30°C and 24°C night. Runner growth and root dry weights were not significantly effected by nematode feeding. Germinated cranberry seedlings were subjected to similar conditions; temperature response was similar to that of cuttings. Root dry weights and runner growth of cranberry seedlings was greater in nematode inoculated treatments than non-inoculated controls: nematode feeding on cranberry roots resulted in an increase of multibranching. This research indicated nematode feeding was detrimental to growth of a variety of plant species. High soil populations of H. similis caused severe reductions to root growth and seed germination. However, since this study was conducted in controlled conditions, it was not substantiated that this nematode caused a reduction of growth to field-grown cranberry plants. Further investigations are needed to correlate these findings with field data to determine pathogenicity on cranberry. Title: The biology and pathogenicity of a sheath nematode Hemicycliophora similis Thorne, 1955 Author: McKewan, Jeanette Anne A study, using greenhouse and laboratory experiments, was made of Hemicycliophora similis from Bandon, Oregon to determine: identity and morphometrics, time and development of a life cycle, host plant preferences and optimum environmental conditions for reproduction and pathogenicity. Morphometric investigations revealed discrepancies between the measurements of this nematode species and those recorded in nematological literature for H. similis. Personal communications with R. P. Esser, H. J. Jensen and B. M. Zuckerman suggested the variations noted do not necessitate describing a new species. For purposes of this research the nematode is named Hemicycliophora sirnilis. Life history investigations were conducted to determine the number of days required to complete a life cycle and the various stages as the nematode developed from egg to egg. Eggs mature to first-stage larvae, without sheath or spear, in 3-5 days and hatch as second-stage larvae in 8-10 days. Second-stage larvae inoculated onto carrot seedlings matured into third-stage larvae in 12-15 days. Fourth-stage larvae appeared in 25-28 days, and adults were present in 35-38 days. Embryonating eggs were observed lodged within an incompletely shed fourth-stage cuticle attached to adult females and within the normal sheath surrounding the adult. One molting specimen was found with two eggs lodged within the fourth-stage cuticle. Such eggs were seen to develop to second-stage larvae; however, none were observed over a long enough time period to determine if larvae hatched and emerged free of the cuticular confinement. Evaluated as hosts were beet, broccoli, carrot, corn, dill, pea, radish, rutabaga, tomato and turnip. Carrot, tomato and turnip supported the highest increase in population; no substantial increase was observed on beet, broccoli, corn and dill. The nematode formed galls consisting of large multibranched growths and reproduced on many of the plant species tested. Galling of seedling roots was most severe on carrot, but slight galling was observed on beet, rutabaga and turnip. Multibranching was observed with varying severity in all hosts. Germination of carrot seeds was reduced substantially when grown in sandy soil infested with H. similis. Slight germination reductions occurred with all hosts tested except corn and pea. Adults and larvae were observed feeding behind root tips and on nematode induced galls. Root discoloration was noted on several plants. To evaluate temperature and soil optima, rooted cranberry cuttings, germinated cranberry seedlings and carrot seedlings were utilized. Carrot seeds were planted in sandy soils of two different textures and pH, infested with H. similis and grown in three temperature regimes: 30°C and 24°C night, 22°C day and 14°C night and 30°C day 6 °C night. The optimum temperature for reproduction on carrot was 22°C day 14°C night in both soil types. A pH gradient developed in cups with the least acidic pH occurring at the base corresponding to maximum nutrient uptake by plant roots. The soil mix in which bog sand from Bandon was incorporated developed a more acidic condition presumably due to the additional organic N content which supplied ammonical nitrogen. The soil mix with Newport sand had no additional organic N and a less acidic condition developed. Maximum nematode population and root density also occurred at the base of the cup. Plants grown in infested soil had sparse multibranched roots; no galls were observed in this experiment. Cranberry cuttings were grown in sterile bog soil from Bandon, Oregon and inoculated with 225 nematodes/450 cc soil. The optimum temperature for nematode reproduction and plant growth was 30°C and 24°C night. Runner growth and root dry weights were not significantly effected by nematode feeding. Germinated cranberry seedlings were subjected to similar conditions; temperature response was similar to that of cuttings. Root dry weights and runner growth of cranberry seedlings was greater in nematode inoculated treatments than non-inoculated controls: nematode feeding on cranberry roots resulted in an increase of multibranching. This research indicated nematode feeding was detrimental to growth of a variety of plant species. High soil populations of H. similis caused severe reductions to root growth and seed germination. However, since this study was conducted in controlled conditions, it was not substantiated that this nematode caused a reduction of growth to field-grown cranberry plants. Further investigations are needed to correlate these findings with field data to determine pathogenicity on cranberry. Close

• 13115. [Article] Responsive pedagogies of practice : researching an ambitious secondary mathematics teacher education design

  Design in secondary mathematics teacher education must prepare teacher candidates to do the work of ambitious and equitable mathematics teaching with skill by situating development in the work of teaching ...

  Citation × Citation Citation Abstract Copy Title: Responsive pedagogies of practice : researching an ambitious secondary mathematics teacher education design Author: Campbell, Matthew Paul, 1983- Design in secondary mathematics teacher education must prepare teacher candidates to do the work of ambitious and equitable mathematics teaching with skill by situating development in the work of teaching and incorporating opportunities to investigate and enact teaching. Teacher education designs must also be responsive to the work that mathematics teachers are expected to do in school settings--which are a product of a set of goals, expectations, and communities that have formed over long histories. This dissertation pursues novel and emerging questions around what the design and implementation of a responsive and practice-focused approach to teacher education--what I call a responsive pedagogy of practice--entails, how those entailments are informed by the work of teaching in schools, and how those entailments inform what individuals do in teacher education programs. Three manuscripts collectively illustrate progress on these ideas, drawing upon data and analyses from design-based research in a secondary mathematics teacher education program. The first manuscript addresses a question of what is meant by and entailed in the design and implementation of a responsive pedagogy of practice. Through an intertwined process of design, implementation, analyses, and revision, three sets of findings informing the development of a theory of responsive pedagogies of practice emerged. First, two needs emerged in addition to the initial attention to developing teacher candidates' instructional skill--aligning with the mathematics of the secondary classroom and developing teacher candidates’ mathematical knowledge for teaching (MKT; Ball, Thames, & Phelps, 2008). The negotiation of these multiple needs poses a challenge for teacher educators. This negotiation also gave rise to a second finding involving the development of instructional skill, which needs to focus on the development on multiple levels of pedagogical tools. Further, a set of pedagogical tools must be derived, in part, from the work that teacher candidates do in school settings. Ultimately, this means that responsiveness in teacher education entails preparing teacher candidates to do what is typically done in school settings while also finding the openings at which to press for more ambitious and equitable teaching practice. Finally, a third finding emerged regarding the novel roles for teacher educators and partner teachers that are constructed through a responsive and practice-focused pedagogy of teacher education. The second manuscript highlights analyses conducted to further investigate the features of the activity of secondary mathematics teaching to which a teacher education design needs to be responsive. Data from teacher candidates' enactments across two settings--the university methods courses and their student teaching placements--were drawn upon to identify the entailments of the activity of secondary mathematics teaching. A modified analytic framework from Leont’ev (1981) and Wertsch, Minick, and Arns (1984) was used to analyze the work of teacher candidates in each setting. While the work in the methods courses emphasized providing students access to mathematics and the orchestration of goal-directed discussions, work in student teaching placements was defined by efficient and productive work on mathematical procedures. Opportunities for more novel instruction were made available contingent on the two expectations being met. These findings have implications for what pedagogical tools should be developed through a responsive pedagogy of practice that enable efficient and procedurally focused mathematics work while also making progress on increasingly ambitious and equitable instruction. The third manuscript highlights an example of how an emerging sense of responsive and practice-focused approaches to teacher education and the work of teacher candidates in school classrooms inform the design features of a responsive pedagogy of practice. A specific design example is put forth that situates opportunities of enactment in the work of addressing students' mathematics errors in the midst of work with students on mathematics procedures. As such, the example is derived from the work that teacher candidates do in school classrooms and also shows how a design can attend to the multiple needs related to teacher candidate and student development. The example serves as one of many activities in development--all of which are subject to further examination through a design-based research process. Title: Responsive pedagogies of practice : researching an ambitious secondary mathematics teacher education design Author: Campbell, Matthew Paul, 1983- Design in secondary mathematics teacher education must prepare teacher candidates to do the work of ambitious and equitable mathematics teaching with skill by situating development in the work of teaching and incorporating opportunities to investigate and enact teaching. Teacher education designs must also be responsive to the work that mathematics teachers are expected to do in school settings--which are a product of a set of goals, expectations, and communities that have formed over long histories. This dissertation pursues novel and emerging questions around what the design and implementation of a responsive and practice-focused approach to teacher education--what I call a responsive pedagogy of practice--entails, how those entailments are informed by the work of teaching in schools, and how those entailments inform what individuals do in teacher education programs. Three manuscripts collectively illustrate progress on these ideas, drawing upon data and analyses from design-based research in a secondary mathematics teacher education program. The first manuscript addresses a question of what is meant by and entailed in the design and implementation of a responsive pedagogy of practice. Through an intertwined process of design, implementation, analyses, and revision, three sets of findings informing the development of a theory of responsive pedagogies of practice emerged. First, two needs emerged in addition to the initial attention to developing teacher candidates' instructional skill--aligning with the mathematics of the secondary classroom and developing teacher candidates’ mathematical knowledge for teaching (MKT; Ball, Thames, & Phelps, 2008). The negotiation of these multiple needs poses a challenge for teacher educators. This negotiation also gave rise to a second finding involving the development of instructional skill, which needs to focus on the development on multiple levels of pedagogical tools. Further, a set of pedagogical tools must be derived, in part, from the work that teacher candidates do in school settings. Ultimately, this means that responsiveness in teacher education entails preparing teacher candidates to do what is typically done in school settings while also finding the openings at which to press for more ambitious and equitable teaching practice. Finally, a third finding emerged regarding the novel roles for teacher educators and partner teachers that are constructed through a responsive and practice-focused pedagogy of teacher education. The second manuscript highlights analyses conducted to further investigate the features of the activity of secondary mathematics teaching to which a teacher education design needs to be responsive. Data from teacher candidates' enactments across two settings--the university methods courses and their student teaching placements--were drawn upon to identify the entailments of the activity of secondary mathematics teaching. A modified analytic framework from Leont’ev (1981) and Wertsch, Minick, and Arns (1984) was used to analyze the work of teacher candidates in each setting. While the work in the methods courses emphasized providing students access to mathematics and the orchestration of goal-directed discussions, work in student teaching placements was defined by efficient and productive work on mathematical procedures. Opportunities for more novel instruction were made available contingent on the two expectations being met. These findings have implications for what pedagogical tools should be developed through a responsive pedagogy of practice that enable efficient and procedurally focused mathematics work while also making progress on increasingly ambitious and equitable instruction. The third manuscript highlights an example of how an emerging sense of responsive and practice-focused approaches to teacher education and the work of teacher candidates in school classrooms inform the design features of a responsive pedagogy of practice. A specific design example is put forth that situates opportunities of enactment in the work of addressing students' mathematics errors in the midst of work with students on mathematics procedures. As such, the example is derived from the work that teacher candidates do in school classrooms and also shows how a design can attend to the multiple needs related to teacher candidate and student development. The example serves as one of many activities in development--all of which are subject to further examination through a design-based research process. Close

• 13116. [Article] Application of transport-reaction modeling to constrain biogeochemical processes in marine sediments

  Quantifying the mass transport through marine sediments, and the geochemical response to such flow with numerical models has become a common and powerful approach for geochemical data interpretation. In ...

  Citation × Citation Citation Abstract Copy Title: Application of transport-reaction modeling to constrain biogeochemical processes in marine sediments Author: Hong, Wei-Li Quantifying the mass transport through marine sediments, and the geochemical response to such flow with numerical models has become a common and powerful approach for geochemical data interpretation. In this dissertation, I developed and applied transport-reaction models to unravel complex and interdependent reactions involving carbon, sulfur and silica transformations in shallow marine sediments, and the impact of physical (mass transport deposits) and depositional events (volcanic ash input) on the overall geochemical state of the system. Carbon cycling in the gas hydrate bearing sediments of the Ulleung Basin was quantified using both box and kinetic modeling approaches. The box model balances mass, flux, and carbon isotopes of carbon (Chapter 2), and led to a better understanding of how methane is cycled in the marine sediments of this area. This effort demonstrates the significance of CO₂ reduction, a previously overlooked reaction. The picture of reaction network derived from this work serves as the foundation for a transport-reaction model (Chapter 3). The kinetic model results revealed a very different biogeochemistry between two distinct fluid-flow environments. At sites where transport is predominantly diffusive (non-chimney environments), organic matter decomposition is the dominant process driving production of methane, dissolved inorganic carbon (DIC) and consumption of sulfate. In contrast, anaerobic oxidation of methane (AOM) drives both carbon and sulfur cycles in the advective settings characterized by acoustic chimneys indicative of gas transport. I show that methane produced within the model domain, through CO₂ reduction and methanogenesis, fuels AOM in the non-chimney sites while AOM is primarily induced by methane from external sources at the chimney sites. A simulation of the system evolution from a non-chimney to a chimney condition was developed by increasing the bottom methane supply to an originally diffusion-controlled site. Results from this exercise show that the higher methane flux leads to a higher AOM activity, and enhanced organic matter decomposition through methanogenesis. Organic carbon cycling is also affected by changes in the depositional environment, as shown by application of the kinetic model to the sediments from the Krishna-Godavary (K-G) basin along the eastern Indian margin (Chapter 4). Proximity to large rivers results in the widespread occurrence of mass transport deposits (MTD) throughout the basin. In this work, MTD is defined as a fluidized sediment block whose pore water composition is identical to sea water value to reflect the homogenization process during sediment transport. The pore water sulfate and ammonium profiles measured at seven sites drilled in the K-G Basin during the NGHP-01 expedition were simulated to provide a quantitative description of how MTDs can affect geochemistry profiles, not only for sulfate and ammonium but potentially all pore water species. This model provides reliable estimates of the MTDs thickness, the time elapsed after the most recent event, and the organoclastic sulfate reduction rate at these seven sites. A transport-reaction modeling approach was also applied to investigate the silica diagenetic reactions fueled by volcanic ash decomposition in Shikuko Basin, Nankai Trough (Chapter 5). The model developed for this setting reproduces a silica diagenetic boundary (SDB) at each site, which is defined by marked decreases in reactive volcanic ash, pore water silica and potassium. Volcanic ash alteration was constrained by modeling pore water ⁸⁷Sr/⁸⁶Sr profiles. Below the SDB, formation of clinoptilolite consumes potassium and regulates the extension of amorphous silica by consuming SiO₂(aq). The observed low SiO₂(aq) and dissolved potassium in these deep sequences require continuous precipitation of clinoptilolite; however in order to maintain oversaturation of this mineral at the low SiO₂(aq) in sediments below the SDB, an increase in pH is required, consistent with pore water observations. Thermal history, rather than temperature alone, controls the inferred reaction network as shown by the convergence of the thermal maturity of sediments at the SDB from all studied sites and is consistent with other locations documented onshore Japan. These results are valuable as we move forward in understanding the mechanisms and consequences of ash alteration in convergent margins worldwide. Title: Application of transport-reaction modeling to constrain biogeochemical processes in marine sediments Author: Hong, Wei-Li Quantifying the mass transport through marine sediments, and the geochemical response to such flow with numerical models has become a common and powerful approach for geochemical data interpretation. In this dissertation, I developed and applied transport-reaction models to unravel complex and interdependent reactions involving carbon, sulfur and silica transformations in shallow marine sediments, and the impact of physical (mass transport deposits) and depositional events (volcanic ash input) on the overall geochemical state of the system. Carbon cycling in the gas hydrate bearing sediments of the Ulleung Basin was quantified using both box and kinetic modeling approaches. The box model balances mass, flux, and carbon isotopes of carbon (Chapter 2), and led to a better understanding of how methane is cycled in the marine sediments of this area. This effort demonstrates the significance of CO₂ reduction, a previously overlooked reaction. The picture of reaction network derived from this work serves as the foundation for a transport-reaction model (Chapter 3). The kinetic model results revealed a very different biogeochemistry between two distinct fluid-flow environments. At sites where transport is predominantly diffusive (non-chimney environments), organic matter decomposition is the dominant process driving production of methane, dissolved inorganic carbon (DIC) and consumption of sulfate. In contrast, anaerobic oxidation of methane (AOM) drives both carbon and sulfur cycles in the advective settings characterized by acoustic chimneys indicative of gas transport. I show that methane produced within the model domain, through CO₂ reduction and methanogenesis, fuels AOM in the non-chimney sites while AOM is primarily induced by methane from external sources at the chimney sites. A simulation of the system evolution from a non-chimney to a chimney condition was developed by increasing the bottom methane supply to an originally diffusion-controlled site. Results from this exercise show that the higher methane flux leads to a higher AOM activity, and enhanced organic matter decomposition through methanogenesis. Organic carbon cycling is also affected by changes in the depositional environment, as shown by application of the kinetic model to the sediments from the Krishna-Godavary (K-G) basin along the eastern Indian margin (Chapter 4). Proximity to large rivers results in the widespread occurrence of mass transport deposits (MTD) throughout the basin. In this work, MTD is defined as a fluidized sediment block whose pore water composition is identical to sea water value to reflect the homogenization process during sediment transport. The pore water sulfate and ammonium profiles measured at seven sites drilled in the K-G Basin during the NGHP-01 expedition were simulated to provide a quantitative description of how MTDs can affect geochemistry profiles, not only for sulfate and ammonium but potentially all pore water species. This model provides reliable estimates of the MTDs thickness, the time elapsed after the most recent event, and the organoclastic sulfate reduction rate at these seven sites. A transport-reaction modeling approach was also applied to investigate the silica diagenetic reactions fueled by volcanic ash decomposition in Shikuko Basin, Nankai Trough (Chapter 5). The model developed for this setting reproduces a silica diagenetic boundary (SDB) at each site, which is defined by marked decreases in reactive volcanic ash, pore water silica and potassium. Volcanic ash alteration was constrained by modeling pore water ⁸⁷Sr/⁸⁶Sr profiles. Below the SDB, formation of clinoptilolite consumes potassium and regulates the extension of amorphous silica by consuming SiO₂(aq). The observed low SiO₂(aq) and dissolved potassium in these deep sequences require continuous precipitation of clinoptilolite; however in order to maintain oversaturation of this mineral at the low SiO₂(aq) in sediments below the SDB, an increase in pH is required, consistent with pore water observations. Thermal history, rather than temperature alone, controls the inferred reaction network as shown by the convergence of the thermal maturity of sediments at the SDB from all studied sites and is consistent with other locations documented onshore Japan. These results are valuable as we move forward in understanding the mechanisms and consequences of ash alteration in convergent margins worldwide. Close

• 13117. [Article] The impact of Oregon’s Coordinated Care Organizations on Prenatal Care Access and Quality : A Difference-in-Differences Analysis

  Background: Prenatal care (PNC) is an important preventive health service that can influence the health of the four million women who give birth annually in the United States, and the health their infants. ...

  Citation × Citation Citation Abstract Copy Title: The impact of Oregon’s Coordinated Care Organizations on Prenatal Care Access and Quality : A Difference-in-Differences Analysis Author: Muoto, Ifeoma O. Background: Prenatal care (PNC) is an important preventive health service that can influence the health of the four million women who give birth annually in the United States, and the health their infants. Despite efforts to increase women’s access to PNC services, significant disparities in PNC utilization and maternal/child health outcomes by insurance type and race/ethnicity persist in the United States. The past decade has witnessed several major health reforms at both national and state levels. However, the impact of these reforms on the quality of PNC, and on disparities in PNC utilization is not known. In 2012, the state of Oregon established Coordinated Care Organizations (CCOs) as comprehensive providers of care for Oregon’s Medicaid beneficiaries. CCOs are characterized by a global budget payment mechanism and financial incentives for high quality care. Timely initiation of PNC – which has been associated with improved maternal and infant health and utilization outcomes – is one of seventeen quality metrics for which CCOs can receive incentive payments. Objectives: The first objective of the current study was to estimate the impact of CCO implementation on the probability of initiating PNC in the first trimester, and on PNC adequacy among Oregon Medicaid beneficiaries. The second objective of the study was to determine if the implementation of CCOs influenced disparities in PNC utilization between Medicaid and privately-insured women, and between non-Hispanic White women and Hispanic/non-Hispanic Black women. Study Design: This quasi-experimental retrospective observational study drew from two data sources: Oregon Vital Records (Birth Certificate statistical files) from the department of Health Analytics of the Oregon state public health department and Washington State’s Linked Birth- CHARS (Comprehensive Hospital Abstract Reporting System) data from the Washington State department of health. A difference-in-differences approach examined PNC utilization before and after CCO implementation. Washington State served as the control group, as its Medicaid financing and delivery systems remained unchanged. Multivariable linear probability analysis was used to control for confounding factors, including maternal age, race/ethnicity, education, parity, marital status, smoking history, previous preterm birth, and maternal morbidity. Population Studied: All births in Oregon and Washington from 2008 – 2013, which were covered by either Medicaid or private insurance, were included in the analysis. Since CCOs started operating mid-year in 2012, June through December 2012 was considered a transition period and births during this period were excluded from the analysis. Principal Findings: CCO implementation was associated with a significant increase in the probability of PNC initiation in the first trimester and a reduction in insurance-type disparities in first trimester PNC initiation and PNC adequacy among Oregon Medicaid beneficiaries. Racial/ethnic disparities did not change following CCO implementation. Conclusions: The implementation of CCOs in Oregon had a positive impact on the timeliness of PNC initiation among Medicaid beneficiaries, and also reduced disparities in PNC quality between Medicaid and privately-insured women. Implications for Policy or Practice: The ongoing health system transformation in Oregon provides an ideal setting to assess the impact of a novel health service delivery model on PNC utilization. If Oregon is successful in this bold and unprecedented move, it could serve as a model for other Medicaid and commercial health plans seeking to improve PNC quality. Further study on the longer-term effects of CCO implementation on PNC quality as well as the effect of CCOs on other health care domains, is warranted. Title: The impact of Oregon’s Coordinated Care Organizations on Prenatal Care Access and Quality : A Difference-in-Differences Analysis Author: Muoto, Ifeoma O. Background: Prenatal care (PNC) is an important preventive health service that can influence the health of the four million women who give birth annually in the United States, and the health their infants. Despite efforts to increase women’s access to PNC services, significant disparities in PNC utilization and maternal/child health outcomes by insurance type and race/ethnicity persist in the United States. The past decade has witnessed several major health reforms at both national and state levels. However, the impact of these reforms on the quality of PNC, and on disparities in PNC utilization is not known. In 2012, the state of Oregon established Coordinated Care Organizations (CCOs) as comprehensive providers of care for Oregon’s Medicaid beneficiaries. CCOs are characterized by a global budget payment mechanism and financial incentives for high quality care. Timely initiation of PNC – which has been associated with improved maternal and infant health and utilization outcomes – is one of seventeen quality metrics for which CCOs can receive incentive payments. Objectives: The first objective of the current study was to estimate the impact of CCO implementation on the probability of initiating PNC in the first trimester, and on PNC adequacy among Oregon Medicaid beneficiaries. The second objective of the study was to determine if the implementation of CCOs influenced disparities in PNC utilization between Medicaid and privately-insured women, and between non-Hispanic White women and Hispanic/non-Hispanic Black women. Study Design: This quasi-experimental retrospective observational study drew from two data sources: Oregon Vital Records (Birth Certificate statistical files) from the department of Health Analytics of the Oregon state public health department and Washington State’s Linked Birth- CHARS (Comprehensive Hospital Abstract Reporting System) data from the Washington State department of health. A difference-in-differences approach examined PNC utilization before and after CCO implementation. Washington State served as the control group, as its Medicaid financing and delivery systems remained unchanged. Multivariable linear probability analysis was used to control for confounding factors, including maternal age, race/ethnicity, education, parity, marital status, smoking history, previous preterm birth, and maternal morbidity. Population Studied: All births in Oregon and Washington from 2008 – 2013, which were covered by either Medicaid or private insurance, were included in the analysis. Since CCOs started operating mid-year in 2012, June through December 2012 was considered a transition period and births during this period were excluded from the analysis. Principal Findings: CCO implementation was associated with a significant increase in the probability of PNC initiation in the first trimester and a reduction in insurance-type disparities in first trimester PNC initiation and PNC adequacy among Oregon Medicaid beneficiaries. Racial/ethnic disparities did not change following CCO implementation. Conclusions: The implementation of CCOs in Oregon had a positive impact on the timeliness of PNC initiation among Medicaid beneficiaries, and also reduced disparities in PNC quality between Medicaid and privately-insured women. Implications for Policy or Practice: The ongoing health system transformation in Oregon provides an ideal setting to assess the impact of a novel health service delivery model on PNC utilization. If Oregon is successful in this bold and unprecedented move, it could serve as a model for other Medicaid and commercial health plans seeking to improve PNC quality. Further study on the longer-term effects of CCO implementation on PNC quality as well as the effect of CCOs on other health care domains, is warranted. Close

• 13118. [Article] Cruise ship disturbance to Kittlitz's murrelets (Brachyramphus brevirostris) in Glacier Bay National Park and Preserve, Alaska

  The Kittlitz's murrelet (Brachyramphus brevirostris), a small pursuit-diving seabird in the family Alcidae, occurs across much of coastal Alaska and parts of the Russian Far East. Glacier Bay National ...

  Citation × Citation Citation Abstract Copy Title: Cruise ship disturbance to Kittlitz's murrelets (Brachyramphus brevirostris) in Glacier Bay National Park and Preserve, Alaska Author: Marcella, Timothy K. The Kittlitz's murrelet (Brachyramphus brevirostris), a small pursuit-diving seabird in the family Alcidae, occurs across much of coastal Alaska and parts of the Russian Far East. Glacier Bay National Park, located in Southeast Alaska, is believed to support approximately 37% of the worldwide breeding population of Kittlitz's murrelets during the summer months. Recent concern over apparent population declines in Alaska, coupled with the Park's dual mandate of resource preservation and visitation, led to this study. Cruise ships, although not the most numerous vessel type operating in Glacier Bay, have previously been identified as the vessel type eliciting the greatest disturbance response from Kittlitz's murrelets. During the murrelet breeding seasons in 2011 and 2012, my field assistants and I collected focal observations of 4,251 Brachyramphus murrelets from the bow of cruise ships traveling through Glacier Bay. Identification of murrelets to species was hampered by both the distance at which murrelets responded to the approaching ship and the type of response to the ship (diving vs. flushing). For roughly 40% of focal observations of murrelets from cruise ships, the species of murrelet (Kittlitz's murrelet or marbled murrelet [B. marmoratus]) could not be identified. Apparent habitat partitioning by the two murrelet species in Glacier Bay resulted in 79% of identified murrelets in the upper section of the Bay (Upper Bay) being Kittlitz's murrelets, while 83% of identified murrelets in the lower section of the Bay (Lower Bay) were marbled murrelets. In the Upper Bay, cruise ships are predicted to disturb 61% of all murrelets within 850 m on either side of the cruise ship's course (i.e., elicited a flushing or diving response), whereas in the Lower Bay, cruise ships are predicted to disturb 72% of murrelets within 850 m of the ship's course. Using Cox multistate models, I demonstrated that murrelets in the Upper Bay (predominantly Kittlitz's murrelets) were more likely to dive than flush in response to approaching cruise ships, whereas murrelets in the Lower Bay (predominantly marbled murrelets) were more likely to flush than dive. Also, murrelets in the Upper Bay responded to cruise ships by flushing or diving at shorter distances from the ship compared to murrelets in the Lower Bay. Murrelets in both areas of Glacier Bay generally reacted to cruise ships at greater distances when the ship approached indirectly, presumably because of the larger profile presented by a passing ship as opposed to a directly advancing ship. Absolute distance of the cruise ship from a focal murrelet was a strong predictor of murrelet disturbance response; no other management-relevant covariates that were measured during this study (e.g., ship velocity, distance to shore, whether a cruise ship had entered the Bay earlier that day) explained a significant proportion of the variation in murrelet response. Inferences based on data collected on-board cruise ships were limited to murrelet disturbance responses that occurred within 1 km of the ship. This was because of limits to the distance from the ship at which behavioral responses could be observed and the a priori assumption that disturbance to murrelets by cruise ships was unlikely at distances greater than 1 km. Results from shipboard observations indicated that some proportion of murrelets encountered at the farthest distance we could make inferences were on occasion disturbed (point estimate at 850 m perpendicular distance from ship's course = 15-30% probability of flushing or diving). This suggests that disturbance of murrelets by cruise ships in Glacier Bay exceeded expected distance thresholds. In order to investigate the effects of cruise ships on murrelet behavior at distances greater than 1 km, my assistants and I collected a total of 643 focal observations of Kittlitz's murrelets during 181 hours of observation from land-based observation sites in the Upper Bay during the 2012 field season. By combining these data with AIS and GPS ship tracks, I was able to append distance to the nearest cruise ship to each focal murrelet observation and search for patterns in murrelet behavior. By collecting data in this manner, I was able to avoid biasing the study based on pre-conceived notions of what constituted a threshold distance for cruise ships to disturb Kittlitz's murrelets. Using a segmented regression model within a logistic regression framework, I found that Kittlitz's murrelets exhibited a disturbance threshold (defined as an increased incidence of flushing from the water) by cruise ships at distances of at least 1.6 km, and perhaps as great as 6.0 km, with a best estimate of threshold disturbance distance at 3.8 km from a cruise ship. When cruise ships were greater than 3.8 km from focal Kittlitz's murrelets, the baseline probability of murrelets flushing during a focal observation period was 12.5%. When cruise ships were less than 3.8 km from focal Kittlitz's murrelets, the probability of flushing increased logistically with decreasing distance to an estimated 48% for the closest approach distances. The unexpectedly long distances at which murrelet behavior was affected by cruise ships in Glacier Bay is most likely attributable to social facilitation by other disturbed murrelets, because similar numbers of murrelets flushed when cruise ships were approaching (n = 30) as when they were receding (n = 27). Once a Kittlitz's murrelet flushed from the water, the subsequent duration of flight did not vary with distance to the nearest cruise ship. Instead, the duration of Kittlitz's murrelet flight was associated with time of day. The strong association between the proximity of cruise ships and the probability of a murrelet flushing, even at distances of several kilometers, demonstrates that Kittlitz's murrelets in Glacier Bay are susceptible to disturbance from cruise ships at distances greater than has previously been published for any seabird. Title: Cruise ship disturbance to Kittlitz's murrelets (Brachyramphus brevirostris) in Glacier Bay National Park and Preserve, Alaska Author: Marcella, Timothy K. The Kittlitz's murrelet (Brachyramphus brevirostris), a small pursuit-diving seabird in the family Alcidae, occurs across much of coastal Alaska and parts of the Russian Far East. Glacier Bay National Park, located in Southeast Alaska, is believed to support approximately 37% of the worldwide breeding population of Kittlitz's murrelets during the summer months. Recent concern over apparent population declines in Alaska, coupled with the Park's dual mandate of resource preservation and visitation, led to this study. Cruise ships, although not the most numerous vessel type operating in Glacier Bay, have previously been identified as the vessel type eliciting the greatest disturbance response from Kittlitz's murrelets. During the murrelet breeding seasons in 2011 and 2012, my field assistants and I collected focal observations of 4,251 Brachyramphus murrelets from the bow of cruise ships traveling through Glacier Bay. Identification of murrelets to species was hampered by both the distance at which murrelets responded to the approaching ship and the type of response to the ship (diving vs. flushing). For roughly 40% of focal observations of murrelets from cruise ships, the species of murrelet (Kittlitz's murrelet or marbled murrelet [B. marmoratus]) could not be identified. Apparent habitat partitioning by the two murrelet species in Glacier Bay resulted in 79% of identified murrelets in the upper section of the Bay (Upper Bay) being Kittlitz's murrelets, while 83% of identified murrelets in the lower section of the Bay (Lower Bay) were marbled murrelets. In the Upper Bay, cruise ships are predicted to disturb 61% of all murrelets within 850 m on either side of the cruise ship's course (i.e., elicited a flushing or diving response), whereas in the Lower Bay, cruise ships are predicted to disturb 72% of murrelets within 850 m of the ship's course. Using Cox multistate models, I demonstrated that murrelets in the Upper Bay (predominantly Kittlitz's murrelets) were more likely to dive than flush in response to approaching cruise ships, whereas murrelets in the Lower Bay (predominantly marbled murrelets) were more likely to flush than dive. Also, murrelets in the Upper Bay responded to cruise ships by flushing or diving at shorter distances from the ship compared to murrelets in the Lower Bay. Murrelets in both areas of Glacier Bay generally reacted to cruise ships at greater distances when the ship approached indirectly, presumably because of the larger profile presented by a passing ship as opposed to a directly advancing ship. Absolute distance of the cruise ship from a focal murrelet was a strong predictor of murrelet disturbance response; no other management-relevant covariates that were measured during this study (e.g., ship velocity, distance to shore, whether a cruise ship had entered the Bay earlier that day) explained a significant proportion of the variation in murrelet response. Inferences based on data collected on-board cruise ships were limited to murrelet disturbance responses that occurred within 1 km of the ship. This was because of limits to the distance from the ship at which behavioral responses could be observed and the a priori assumption that disturbance to murrelets by cruise ships was unlikely at distances greater than 1 km. Results from shipboard observations indicated that some proportion of murrelets encountered at the farthest distance we could make inferences were on occasion disturbed (point estimate at 850 m perpendicular distance from ship's course = 15-30% probability of flushing or diving). This suggests that disturbance of murrelets by cruise ships in Glacier Bay exceeded expected distance thresholds. In order to investigate the effects of cruise ships on murrelet behavior at distances greater than 1 km, my assistants and I collected a total of 643 focal observations of Kittlitz's murrelets during 181 hours of observation from land-based observation sites in the Upper Bay during the 2012 field season. By combining these data with AIS and GPS ship tracks, I was able to append distance to the nearest cruise ship to each focal murrelet observation and search for patterns in murrelet behavior. By collecting data in this manner, I was able to avoid biasing the study based on pre-conceived notions of what constituted a threshold distance for cruise ships to disturb Kittlitz's murrelets. Using a segmented regression model within a logistic regression framework, I found that Kittlitz's murrelets exhibited a disturbance threshold (defined as an increased incidence of flushing from the water) by cruise ships at distances of at least 1.6 km, and perhaps as great as 6.0 km, with a best estimate of threshold disturbance distance at 3.8 km from a cruise ship. When cruise ships were greater than 3.8 km from focal Kittlitz's murrelets, the baseline probability of murrelets flushing during a focal observation period was 12.5%. When cruise ships were less than 3.8 km from focal Kittlitz's murrelets, the probability of flushing increased logistically with decreasing distance to an estimated 48% for the closest approach distances. The unexpectedly long distances at which murrelet behavior was affected by cruise ships in Glacier Bay is most likely attributable to social facilitation by other disturbed murrelets, because similar numbers of murrelets flushed when cruise ships were approaching (n = 30) as when they were receding (n = 27). Once a Kittlitz's murrelet flushed from the water, the subsequent duration of flight did not vary with distance to the nearest cruise ship. Instead, the duration of Kittlitz's murrelet flight was associated with time of day. The strong association between the proximity of cruise ships and the probability of a murrelet flushing, even at distances of several kilometers, demonstrates that Kittlitz's murrelets in Glacier Bay are susceptible to disturbance from cruise ships at distances greater than has previously been published for any seabird. Close

• 13119. [Article] Abrupt deglacial climate changes in the North Pacific and implications for climate tipping points

  Paleoclimate archives have revealed abrupt climate events that are superimposed on more gradual climate changes throughout the last glacial and deglacial periods. The underlying causes of such rapid climate ...

  Citation × Citation Citation Abstract Copy Title: Abrupt deglacial climate changes in the North Pacific and implications for climate tipping points Author: Praetorius, Summer Kate Paleoclimate archives have revealed abrupt climate events that are superimposed on more gradual climate changes throughout the last glacial and deglacial periods. The underlying causes of such rapid climate changes are still poorly understood, but the strong expression of these events in northern hemisphere records likely points to climatic mechanisms of a northern origin. A leading hypothesis for the trigger of these climate fluctuations has been changes in the strength of the Atlantic meridional overturning circulation (AMOC). However, the very rapid nature of some of the observed climate transitions (3-50 years) suggests a potential role for abrupt shifts in atmospheric circulation or nonlinear feedbacks within the climate system. Understanding the relative timing and magnitude of these events in different regions of the globe will help to identify the sources and possible amplifying mechanisms that have led to abrupt climate changes in the past, which will provide insight and constraints on the potential for abrupt climate changes in the future. This dissertation seeks to characterize climate changes occurring in the Northeast Pacific during the last deglaciation, a time period that encompasses the dynamic transition between the last ice age and the modern day interglacial period. So far, high-resolution records with precise chronologies from the North Pacific have been sparse, and paleoclimate models and proxy reconstructions disagree about the deglacial climate changes that are both predicted and observed to have occurred in this region. Marine sediment records from the Gulf of Alaska (GOA) have exceptionally high resolution (~1 cm/yr), making it possible to reconstruct climate changes in unprecedented detail for the North Pacific region. We establish new multi-decadal scale records of surface ocean variability using planktonic oxygen isotopes and sea-surface temperature (SST) estimates based on the alkenone U₃₇[superscript K'] unsaturation index, as well as regional records of ice-rafting and deglacial volcanic activity sourced from the Mt. Edgecumbe volcanic field (MEVF). The age models for these records are constrained by high-precision radiocarbon dating, tephra correlation, and "tuning" to the decadal-scale North Greenland Ice Core Project (NGRIP) oxygen isotope record. We combine new and previously published data from a depth transect of marine sites in the GOA and Northeast Pacific to place surface ocean changes in context of oceanic variability throughout the water column. These reconstructions are then used to evaluate three fundamental questions: 1) what are the timing and patterns of deglacial climate changes in the North Pacific relative to other regions, 2) what are the potential forcing mechanisms for deglacial climate variability in this region, and 3) how does the subsurface ocean respond to and influence abrupt climate change. In chapter two, we compare the timing and patterns of climate changes occurring between the North Pacific and North Atlantic regions. A major debate in the paleoclimate literature has been whether these regions operate in a synchronized or seesaw like mode. We compare the high resolution GOA and NGRIP oxygen isotope records as proxies for local temperature, and find that both synchronous and asynchronous climate patterns occur between regions throughout the past 18,000 years. The most abrupt climate transitions are preceded/accompanied by synchronous behavior, whereas times of relative climate stability exhibit asynchronous or anticorrelated (seesaw) patterns. This implies that coupling of North Pacific and North Atlantic heat transport could act as an amplifying mechanism in abrupt northern hemisphere climate change, whereas opposing oceanic regimes could act to balance northern hemisphere heat transport, and thus promote climate stability. In chapter three, we examine the timing between regional deglaciation and volcanism to evaluate potential feedbacks between climate and volcanic activity. Although volcanic eruptions have been observed to contribute to abrupt climate fluctuations with global effects in historical times, the role of volcanic forcing in climate variability of the more distant past (prior to the Holocene) has been neglected due to the very short-time scales in which volcanic events occur, and the difficulty of obtaining records with high enough resolution to capture these events and their associated climate effects. We evaluate the source and timing of a sequence of 23 tephra layers preserved in high-accumulation rate sediment cores proximal to the MEVF, and examine the regional climate response to this volcanic activity through comparison with reconstructions of sea surface temperatures, oxygen isotopes, and the δ¹⁸O of seawater. We find that the onset of enhanced volcanic activity coincides with abrupt warming at the onset of the Bølling Allerød, regional retreat of glaciers, and a period of rapid vertical land motion predicted from a model of regional isostatic rebound. These finding support the hypothesis that deglaciation may promote volcanism by removing crustal loading. The records of sea surface variability show large fluctuations during the episode of intense volcanic activity, suggesting that deglacial volcanic activity may not only respond to climate, but may also contribute to climate variance during the deglacial interval. In Chapter four, we examine the oceanographic changes that lead to two episodes of hypoxia in the GOA that lasted for millennia during the deglaciation. Similar hypoxic events have been documented across the North Pacific, indicating a widespread expansion of the oxygen minimum zone (OMZ) during the Bølling Allerød and early Holocene warm periods. These episodes have been linked to enhanced export productivity in many sites, however, the driving mechanisms for enhanced productivity and ocean deoxygenation remain elusive. Our alkenone temperature reconstructions reveal two abrupt warmings of 4-5°C that precisely coincide with the onset of increased export productivity and a sudden shift to hypoxic conditions, suggesting a strong link between ocean warming, marine productivity, and deoxygenation. Oxygen isotopes throughout the water column indicate that a transient subsurface warming of ~2°C might have accompanied the first hypoxic event during the BA. We propose that abrupt ocean warming lead to an expansion of the North Pacific OMZ through a reduction in oxygen solubility, enhanced thermal stratification, and a stimulation of marine productivity through the stabilization of the euphotic zone (related to stratification), combined with enhanced nutrient input from remobilization of iron in hypoxic shelf sediments. These studies indicate that large surface and subsurface ocean changes occurred in the North Pacific during the last deglaciation, with the potential for important feedbacks on global climate. Title: Abrupt deglacial climate changes in the North Pacific and implications for climate tipping points Author: Praetorius, Summer Kate Paleoclimate archives have revealed abrupt climate events that are superimposed on more gradual climate changes throughout the last glacial and deglacial periods. The underlying causes of such rapid climate changes are still poorly understood, but the strong expression of these events in northern hemisphere records likely points to climatic mechanisms of a northern origin. A leading hypothesis for the trigger of these climate fluctuations has been changes in the strength of the Atlantic meridional overturning circulation (AMOC). However, the very rapid nature of some of the observed climate transitions (3-50 years) suggests a potential role for abrupt shifts in atmospheric circulation or nonlinear feedbacks within the climate system. Understanding the relative timing and magnitude of these events in different regions of the globe will help to identify the sources and possible amplifying mechanisms that have led to abrupt climate changes in the past, which will provide insight and constraints on the potential for abrupt climate changes in the future. This dissertation seeks to characterize climate changes occurring in the Northeast Pacific during the last deglaciation, a time period that encompasses the dynamic transition between the last ice age and the modern day interglacial period. So far, high-resolution records with precise chronologies from the North Pacific have been sparse, and paleoclimate models and proxy reconstructions disagree about the deglacial climate changes that are both predicted and observed to have occurred in this region. Marine sediment records from the Gulf of Alaska (GOA) have exceptionally high resolution (~1 cm/yr), making it possible to reconstruct climate changes in unprecedented detail for the North Pacific region. We establish new multi-decadal scale records of surface ocean variability using planktonic oxygen isotopes and sea-surface temperature (SST) estimates based on the alkenone U₃₇[superscript K'] unsaturation index, as well as regional records of ice-rafting and deglacial volcanic activity sourced from the Mt. Edgecumbe volcanic field (MEVF). The age models for these records are constrained by high-precision radiocarbon dating, tephra correlation, and "tuning" to the decadal-scale North Greenland Ice Core Project (NGRIP) oxygen isotope record. We combine new and previously published data from a depth transect of marine sites in the GOA and Northeast Pacific to place surface ocean changes in context of oceanic variability throughout the water column. These reconstructions are then used to evaluate three fundamental questions: 1) what are the timing and patterns of deglacial climate changes in the North Pacific relative to other regions, 2) what are the potential forcing mechanisms for deglacial climate variability in this region, and 3) how does the subsurface ocean respond to and influence abrupt climate change. In chapter two, we compare the timing and patterns of climate changes occurring between the North Pacific and North Atlantic regions. A major debate in the paleoclimate literature has been whether these regions operate in a synchronized or seesaw like mode. We compare the high resolution GOA and NGRIP oxygen isotope records as proxies for local temperature, and find that both synchronous and asynchronous climate patterns occur between regions throughout the past 18,000 years. The most abrupt climate transitions are preceded/accompanied by synchronous behavior, whereas times of relative climate stability exhibit asynchronous or anticorrelated (seesaw) patterns. This implies that coupling of North Pacific and North Atlantic heat transport could act as an amplifying mechanism in abrupt northern hemisphere climate change, whereas opposing oceanic regimes could act to balance northern hemisphere heat transport, and thus promote climate stability. In chapter three, we examine the timing between regional deglaciation and volcanism to evaluate potential feedbacks between climate and volcanic activity. Although volcanic eruptions have been observed to contribute to abrupt climate fluctuations with global effects in historical times, the role of volcanic forcing in climate variability of the more distant past (prior to the Holocene) has been neglected due to the very short-time scales in which volcanic events occur, and the difficulty of obtaining records with high enough resolution to capture these events and their associated climate effects. We evaluate the source and timing of a sequence of 23 tephra layers preserved in high-accumulation rate sediment cores proximal to the MEVF, and examine the regional climate response to this volcanic activity through comparison with reconstructions of sea surface temperatures, oxygen isotopes, and the δ¹⁸O of seawater. We find that the onset of enhanced volcanic activity coincides with abrupt warming at the onset of the Bølling Allerød, regional retreat of glaciers, and a period of rapid vertical land motion predicted from a model of regional isostatic rebound. These finding support the hypothesis that deglaciation may promote volcanism by removing crustal loading. The records of sea surface variability show large fluctuations during the episode of intense volcanic activity, suggesting that deglacial volcanic activity may not only respond to climate, but may also contribute to climate variance during the deglacial interval. In Chapter four, we examine the oceanographic changes that lead to two episodes of hypoxia in the GOA that lasted for millennia during the deglaciation. Similar hypoxic events have been documented across the North Pacific, indicating a widespread expansion of the oxygen minimum zone (OMZ) during the Bølling Allerød and early Holocene warm periods. These episodes have been linked to enhanced export productivity in many sites, however, the driving mechanisms for enhanced productivity and ocean deoxygenation remain elusive. Our alkenone temperature reconstructions reveal two abrupt warmings of 4-5°C that precisely coincide with the onset of increased export productivity and a sudden shift to hypoxic conditions, suggesting a strong link between ocean warming, marine productivity, and deoxygenation. Oxygen isotopes throughout the water column indicate that a transient subsurface warming of ~2°C might have accompanied the first hypoxic event during the BA. We propose that abrupt ocean warming lead to an expansion of the North Pacific OMZ through a reduction in oxygen solubility, enhanced thermal stratification, and a stimulation of marine productivity through the stabilization of the euphotic zone (related to stratification), combined with enhanced nutrient input from remobilization of iron in hypoxic shelf sediments. These studies indicate that large surface and subsurface ocean changes occurred in the North Pacific during the last deglaciation, with the potential for important feedbacks on global climate. Close

• 13120. [Article] Restoring the Columbia River Estuary : Chinook Salmon Recovery and Invasive Species Management

  As highlighted in this study, shallow-water habitats and the prey they provide are important for juvenile salmon in the Columbia River estuary, but the spread of invasive species and large-scale changes ...

  Citation × Citation Citation Abstract Copy Title: Restoring the Columbia River Estuary : Chinook Salmon Recovery and Invasive Species Management Author: Klopfenstein, Rachael As highlighted in this study, shallow-water habitats and the prey they provide are important for juvenile salmon in the Columbia River estuary, but the spread of invasive species and large-scale changes to the estuary influence how these habitats are utilized. Reed canarygrass (Phalaris arundinacea) (“PHAR” hereafter) is a highly invasive aquatic plant species that affects a number of emergent wetland habitats in the upper Columbia River estuary, and is of concern to those trying to restore important shallow-water habitats for juvenile salmon. The presence of PHAR undoubtedly reduces plant diversity, but this study seeked to elucidate how PHAR affects juvenile Chinook Salmon rearing success relative to natural emergent vegetation. The study further evaluated the importance of wetland-deriver prey to juveniles found in shallow-water habitats along a habitat gradient (i.e., back-water channel, confluence, and main stem). We conducted research at a floodplain wetland restoration site in the tidal-fluvial portion of the estuary, where a water control structure is used to manage water levels and the spread of PHAR. The goal of the research was to compare two microhabitats within the floodplain: areas dominated by PHAR and areas dominated by natural emergent vegetation. Using hatchery-raised juvenile Chinook salmon, we designed a series of feeding experiments in artificial enclosures to determine whether invasive PHAR and natural emergent vegetation provide similar foraging and growth opportunities for juvenile salmon. We further identified differences in physical and biological parameters of each habitat (e.g., temperature, dissolved oxygen, and invertebrate community) and examined feeding characteristics (e.g., diet composition and modeled growth rates) for juveniles through a stomach content analysis. Additionally, we conducted beach seining and diet analysis for fish collected along a habitat gradient and compared the diet composition and modeled growth rates between the sample areas. In the floodplain wetland, invertebrate prey compositions from the 2015-2016 (March- June) fallout and emergence traps were similar, but prey abundances and diversity varied seasonally. Across both years, for emergence traps, the average total density (per m²) of invertebrates in the natural vegetation and in PHAR was 154±18 m² and 225±34 m², respectively, and for the fallout traps was 664±95 m² and 662±64 m², respectively. Salmon diets were mostly similar, and a large proportion of diets in both habitats were made up of Copepoda/Cladocera (60-98% composition by biomass). Growth during the net pen experiment differed significantly between the two vegetation types (Kruskal-Wallis: p<0.001), with fish growing more in the natural emergent vegetation. In 2015, juveniles grew an average 6.4 mm FL in the natural emergent vegetation, compared to 4.7 mm FL in PHAR, and consumed fewer Copepoda/Cladocera and more Diptera over the 10 days. In 2016, juveniles grew an average 9.2 mm FL in the natural emergent vegetation compared to 7.6 mm FL in PHAR. In 2016, fish from both habitats consumed a higher abundance of Copepoda/Cladocera and grew more, despite poor water quality conditions at the site. Of the subyearlings (n=170) and yearlings (n=14) collected in habitats adjacent to the floodplain wetland, 48% were of known hatchery origin. Modeled potential growth rates for subyearlings were similar on average between February and May in the back channel, confluence, and main stem, ranging from 0.067–0.07 g/g/d, but the rates varied seasonally. Growth potential was higher in the back channel habitat earlier in the sampling season (February-March), as the modeled daily growth rates were 0.08 g/g/d compared to 0.06 g/g/d in the main stem. All fish collected prior to May were relatively small and unclipped, highlighting the seasonal benefits of shallow-water habitats to support a variety of life-history traits. When comparing modeled growth rates of the juveniles reared at the floodplain wetland compared to the in adjacent habitats, estimates from the floodplain wetland were higher across all months. Restoration of shallow-water habitats is important for the overall health of the estuary, but the effects of large-scale ecosystem changes (e.g., flow regulation and spread invasive species) on salmon recovery and estuary-management decisions are uncertain. For example, water control structures to limit the spread of PHAR also reduce fish access to floodplain habitats, and fewer high-flow events further limit fish access and may facilitate the spread of invasive species. PHAR has been shown to reduce overall plant diversity and, as observed in this study, may provide habitat that is less suitable to juvenile Chinook Salmon. The high density of important prey for salmon found at the site, regardless of the presence of PHAR, and high potential growth measured at the site, emphasize the importance of restoring shallow-water habitats that are accessible to juvenile Chinook Salmon in the upper estuary. Title: Restoring the Columbia River Estuary : Chinook Salmon Recovery and Invasive Species Management Author: Klopfenstein, Rachael As highlighted in this study, shallow-water habitats and the prey they provide are important for juvenile salmon in the Columbia River estuary, but the spread of invasive species and large-scale changes to the estuary influence how these habitats are utilized. Reed canarygrass (Phalaris arundinacea) (“PHAR” hereafter) is a highly invasive aquatic plant species that affects a number of emergent wetland habitats in the upper Columbia River estuary, and is of concern to those trying to restore important shallow-water habitats for juvenile salmon. The presence of PHAR undoubtedly reduces plant diversity, but this study seeked to elucidate how PHAR affects juvenile Chinook Salmon rearing success relative to natural emergent vegetation. The study further evaluated the importance of wetland-deriver prey to juveniles found in shallow-water habitats along a habitat gradient (i.e., back-water channel, confluence, and main stem). We conducted research at a floodplain wetland restoration site in the tidal-fluvial portion of the estuary, where a water control structure is used to manage water levels and the spread of PHAR. The goal of the research was to compare two microhabitats within the floodplain: areas dominated by PHAR and areas dominated by natural emergent vegetation. Using hatchery-raised juvenile Chinook salmon, we designed a series of feeding experiments in artificial enclosures to determine whether invasive PHAR and natural emergent vegetation provide similar foraging and growth opportunities for juvenile salmon. We further identified differences in physical and biological parameters of each habitat (e.g., temperature, dissolved oxygen, and invertebrate community) and examined feeding characteristics (e.g., diet composition and modeled growth rates) for juveniles through a stomach content analysis. Additionally, we conducted beach seining and diet analysis for fish collected along a habitat gradient and compared the diet composition and modeled growth rates between the sample areas. In the floodplain wetland, invertebrate prey compositions from the 2015-2016 (March- June) fallout and emergence traps were similar, but prey abundances and diversity varied seasonally. Across both years, for emergence traps, the average total density (per m²) of invertebrates in the natural vegetation and in PHAR was 154±18 m² and 225±34 m², respectively, and for the fallout traps was 664±95 m² and 662±64 m², respectively. Salmon diets were mostly similar, and a large proportion of diets in both habitats were made up of Copepoda/Cladocera (60-98% composition by biomass). Growth during the net pen experiment differed significantly between the two vegetation types (Kruskal-Wallis: p<0.001), with fish growing more in the natural emergent vegetation. In 2015, juveniles grew an average 6.4 mm FL in the natural emergent vegetation, compared to 4.7 mm FL in PHAR, and consumed fewer Copepoda/Cladocera and more Diptera over the 10 days. In 2016, juveniles grew an average 9.2 mm FL in the natural emergent vegetation compared to 7.6 mm FL in PHAR. In 2016, fish from both habitats consumed a higher abundance of Copepoda/Cladocera and grew more, despite poor water quality conditions at the site. Of the subyearlings (n=170) and yearlings (n=14) collected in habitats adjacent to the floodplain wetland, 48% were of known hatchery origin. Modeled potential growth rates for subyearlings were similar on average between February and May in the back channel, confluence, and main stem, ranging from 0.067–0.07 g/g/d, but the rates varied seasonally. Growth potential was higher in the back channel habitat earlier in the sampling season (February-March), as the modeled daily growth rates were 0.08 g/g/d compared to 0.06 g/g/d in the main stem. All fish collected prior to May were relatively small and unclipped, highlighting the seasonal benefits of shallow-water habitats to support a variety of life-history traits. When comparing modeled growth rates of the juveniles reared at the floodplain wetland compared to the in adjacent habitats, estimates from the floodplain wetland were higher across all months. Restoration of shallow-water habitats is important for the overall health of the estuary, but the effects of large-scale ecosystem changes (e.g., flow regulation and spread invasive species) on salmon recovery and estuary-management decisions are uncertain. For example, water control structures to limit the spread of PHAR also reduce fish access to floodplain habitats, and fewer high-flow events further limit fish access and may facilitate the spread of invasive species. PHAR has been shown to reduce overall plant diversity and, as observed in this study, may provide habitat that is less suitable to juvenile Chinook Salmon. The high density of important prey for salmon found at the site, regardless of the presence of PHAR, and high potential growth measured at the site, emphasize the importance of restoring shallow-water habitats that are accessible to juvenile Chinook Salmon in the upper estuary. Close

• 13121. [Article] Factors affecting within-season and between-season breeding dispersal of burrowing owls in California

  Dispersal is integral to our understanding of the life history and population biology of many vertebrates, but difficulties in detecting long distance movements have complicated its study. Moreover, studies ...

  Citation × Citation Citation Abstract Copy Title: Factors affecting within-season and between-season breeding dispersal of burrowing owls in California Author: Catlin, Daniel H. Dispersal is integral to our understanding of the life history and population biology of many vertebrates, but difficulties in detecting long distance movements have complicated its study. Moreover, studies of factors affecting dispersal are often unable to determine the relative contributions of variables such as nesting success, mate fidelity, and nest site fidelity. I examined the effects of nest depredation on dispersal in comparison to successful nests and nests that failed for other reasons. Additionally, I investigated a suite of biological factors affecting within-season and between-season breeding dispersal by burrowing owls (Athene cunicularia) in California, attempting to partition the effects of these covariates and to deal with long distance detectibility issues. For both types of dispersal, I divided dispersal into two components; dispersal probability and dispersal distance. I used experimental and observational approaches to investigate within-season dispersal in two contrasting environments; a large grassland and an agricultural landscape. I found that the factors affecting dispersal probability and dispersal distance were different, supporting my decision to examine each separately. Of the factors investigated, dispersal probability was influenced most by study area, mate fidelity, and nesting success. The proportion of individuals dispersing tended to be greater for owls that lost their mate due to death or dispersal (60%, 6 of 10) and owls whose nests were depredated (50%, 10 of 20) than for owls that did not lose their mates (33%, 6 of 18) and owls whose nests were successful (17%, 1 of 6), respectively. The results from an experiment where we removed eggs from pairs of owls to simulate nest depredation were consistent with the observational results, suggesting that owls whose nests were depredated may have been more likely to disperse than control owls. The reactions of owls from depredated nests, however, did not appear to differ from those whose nests failed for other reasons. In contrast, owl dispersal distance was most affected by owl gender, and to a lesser degree by study area and nesting success. Dispersal distance was greater for female owls (median = 1575 m, n = 13) than male owls (median = 417 m, n = 11), greater for owls from the grassland area (median= 939 m, n = 9) compared to owls from the agricultural area (median = 829 m, n = 15), and greater for owls whose nests had failed (median = 1018 m, n = 17) than for owls that successfully bred (median 475 m, n = 7). Nest depredation, however, did not appear to increase dispersal distance. The geometric models performed poorly at approximating within-season dispersal distance, indicating that many owls disperse farther than predicted by a "first is best" model. I speculate that the distribution of within-season dispersal distances by burrowing owls is related to the densities of suitable territories and mates, which are more variable than predicted by a geometric model within a breeding season. I used data from band resightings and nesting success (1998-2003) to examine factors related to between-season breeding dispersal by burrowing owls in an agricultural environment. Of the factors investigated, nesting success appeared to have the greatest effect on burrowing owl dispersal. The proportion of individuals dispersing was greater for owls whose nests had failed (68%, 28 of 41) than owls whose nests were successful (27%, 58 of 212). Similarly, dispersal distance was greater for owls whose nest failed (mean = 745 ± 175 m, n = 28) than owls with successful nests (mean = 340 ± 36 m,n = 58). The owls exhibited high rates of nest site and mate fidelity between breeding seasons. There was evidence that previous experience at a breeding site may have reduced dispersal probability and that unpaired owls may have been more likely to disperse and dispersed slightly greater distances than those that retained their mates. Nesting success, however, appeared to be the major factor contributing to burrowing owl breeding dispersal after controlling for nest site and mate fidelity, particularly for male owls. Despite the complexity of the dispersal process, a geometric model provided a reasonably good fit to the distribution of between-season breeding dispersal distances at relatively short distances, but failed to predict a small percentage of long distance dispersals. Geometric models appeared to be a better fit for the distribution of between-season breeding dispersal distances than within-season breeding dispersal distances. Factors affecting within-season dispersal were generally similar to those affecting between-season dispersal. Both within-season and between-season breeding dispersal were affected by nesting success and mate fidelity, but the effects of these factors differed between the two types of breeding dispersal, suggesting that time constraints and competition play a larger role in within-season dispersal than between season dispersal. In addition, both studies supported a difference in dispersal behavior, in which the factors that affected dispersal probability were distinct from those that affected dispersal distance. These results help determine the relative contributions of nesting success, mate fidelity, and nest site fidelity to avian dispersal, offer some evidence that the effects of nest depredation are not distinct from the effects of nest failure in general, and provide further support for the division of dispersal into dispersal probability and dispersal distance. Title: Factors affecting within-season and between-season breeding dispersal of burrowing owls in California Author: Catlin, Daniel H. Dispersal is integral to our understanding of the life history and population biology of many vertebrates, but difficulties in detecting long distance movements have complicated its study. Moreover, studies of factors affecting dispersal are often unable to determine the relative contributions of variables such as nesting success, mate fidelity, and nest site fidelity. I examined the effects of nest depredation on dispersal in comparison to successful nests and nests that failed for other reasons. Additionally, I investigated a suite of biological factors affecting within-season and between-season breeding dispersal by burrowing owls (Athene cunicularia) in California, attempting to partition the effects of these covariates and to deal with long distance detectibility issues. For both types of dispersal, I divided dispersal into two components; dispersal probability and dispersal distance. I used experimental and observational approaches to investigate within-season dispersal in two contrasting environments; a large grassland and an agricultural landscape. I found that the factors affecting dispersal probability and dispersal distance were different, supporting my decision to examine each separately. Of the factors investigated, dispersal probability was influenced most by study area, mate fidelity, and nesting success. The proportion of individuals dispersing tended to be greater for owls that lost their mate due to death or dispersal (60%, 6 of 10) and owls whose nests were depredated (50%, 10 of 20) than for owls that did not lose their mates (33%, 6 of 18) and owls whose nests were successful (17%, 1 of 6), respectively. The results from an experiment where we removed eggs from pairs of owls to simulate nest depredation were consistent with the observational results, suggesting that owls whose nests were depredated may have been more likely to disperse than control owls. The reactions of owls from depredated nests, however, did not appear to differ from those whose nests failed for other reasons. In contrast, owl dispersal distance was most affected by owl gender, and to a lesser degree by study area and nesting success. Dispersal distance was greater for female owls (median = 1575 m, n = 13) than male owls (median = 417 m, n = 11), greater for owls from the grassland area (median= 939 m, n = 9) compared to owls from the agricultural area (median = 829 m, n = 15), and greater for owls whose nests had failed (median = 1018 m, n = 17) than for owls that successfully bred (median 475 m, n = 7). Nest depredation, however, did not appear to increase dispersal distance. The geometric models performed poorly at approximating within-season dispersal distance, indicating that many owls disperse farther than predicted by a "first is best" model. I speculate that the distribution of within-season dispersal distances by burrowing owls is related to the densities of suitable territories and mates, which are more variable than predicted by a geometric model within a breeding season. I used data from band resightings and nesting success (1998-2003) to examine factors related to between-season breeding dispersal by burrowing owls in an agricultural environment. Of the factors investigated, nesting success appeared to have the greatest effect on burrowing owl dispersal. The proportion of individuals dispersing was greater for owls whose nests had failed (68%, 28 of 41) than owls whose nests were successful (27%, 58 of 212). Similarly, dispersal distance was greater for owls whose nest failed (mean = 745 ± 175 m, n = 28) than owls with successful nests (mean = 340 ± 36 m,n = 58). The owls exhibited high rates of nest site and mate fidelity between breeding seasons. There was evidence that previous experience at a breeding site may have reduced dispersal probability and that unpaired owls may have been more likely to disperse and dispersed slightly greater distances than those that retained their mates. Nesting success, however, appeared to be the major factor contributing to burrowing owl breeding dispersal after controlling for nest site and mate fidelity, particularly for male owls. Despite the complexity of the dispersal process, a geometric model provided a reasonably good fit to the distribution of between-season breeding dispersal distances at relatively short distances, but failed to predict a small percentage of long distance dispersals. Geometric models appeared to be a better fit for the distribution of between-season breeding dispersal distances than within-season breeding dispersal distances. Factors affecting within-season dispersal were generally similar to those affecting between-season dispersal. Both within-season and between-season breeding dispersal were affected by nesting success and mate fidelity, but the effects of these factors differed between the two types of breeding dispersal, suggesting that time constraints and competition play a larger role in within-season dispersal than between season dispersal. In addition, both studies supported a difference in dispersal behavior, in which the factors that affected dispersal probability were distinct from those that affected dispersal distance. These results help determine the relative contributions of nesting success, mate fidelity, and nest site fidelity to avian dispersal, offer some evidence that the effects of nest depredation are not distinct from the effects of nest failure in general, and provide further support for the division of dispersal into dispersal probability and dispersal distance. Close

• 13122. [Article] DANCE AS COMMUNICATION: HOW HUMANS COMMUNICATE THROUGH DANCE AND PERCEIVE DANCE AS COMMUNICATION

  58 pages. A thesis presented to the Department of Dance and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Arts, Spring 2016.

  Citation × Citation Citation Abstract Copy Title: DANCE AS COMMUNICATION: HOW HUMANS COMMUNICATE THROUGH DANCE AND PERCEIVE DANCE AS COMMUNICATION Author: Rounds, Samantha Year: 2016 58 pages. A thesis presented to the Department of Dance and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Arts, Spring 2016. Title: DANCE AS COMMUNICATION: HOW HUMANS COMMUNICATE THROUGH DANCE AND PERCEIVE DANCE AS COMMUNICATION Author: Rounds, Samantha Year: 2016 58 pages. A thesis presented to the Department of Dance and the Clark Honors College of the University of Oregon in partial fulfillment of the requirements for degree of Bachelor of Arts, Spring 2016. Close

• 13123. [Article] Distribution and movements of Chinook salmon, Oncorhynchus tshawytscha, returning to the Yukon River basin

  Chinook salmon, Oncorhynchus tshawytscha, returning to the Yukon River basin and other large river systems in western Alaska have declined dramatically since the late 1990s. This continuing trend has ...

  Citation × Citation Citation Abstract Copy Title: Distribution and movements of Chinook salmon, Oncorhynchus tshawytscha, returning to the Yukon River basin Author: Eiler, John H. Chinook salmon, Oncorhynchus tshawytscha, returning to the Yukon River basin and other large river systems in western Alaska have declined dramatically since the late 1990s. This continuing trend has raised concerns over the future status of the returns, and severely impacted commercial and subsistence fisheries within the drainage. Management is further complicated by the mixed-stock composition of the run, the presence of other temporally similar salmon species, and the need to equitably allocate harvests between the numerous fisheries and user groups scattered throughout the basin. Detailed information is needed on Chinook salmon run characteristics to better understand and manage the returns, and facilitate conservation efforts. However, this goal is exacerbated by the massive size and remote nature of the basin, the large number of highly mobile fish, and the compressed timing of the run. To address these challenges, radio telemetry was used to determine the stock composition and spawning distribution of the returns, and the migratory characteristics of the fish. The migratory patterns exhibited by returning salmon provide a number of insights into the status of the run. Since the Yukon River is essentially free-flowing (i.e., not regulated), this study also presented an opportunity to document the distribution and upriver movements of large returns of wild Chinook salmon under natural conditions. During 2002-2004, returning adult Chinook salmon were captured in the lower Yukon River (approximately 300 km upriver from the river mouth), tagged with radio transmitters, and tracked upriver using remote tracking stations located on important migratory routes and major spawning tributaries. Aerial tracking surveys were used to locate fish in spawning areas and between stations. The fish responded well to the capture and handling procedures, with most (2,790, 98%) resuming upriver movements. Although the fish initially displayed a negative tagging response, with slower migration rates observed immediately after release, the duration of this response was relatively short (several days) and less severe as the fish moved upriver. Independent measures indicated that the swimming speeds and timing of the fish upriver from the tagging area were comparable to untagged fish, suggesting that the tagging methods used were relatively benign. Fish returned to spawning areas throughout the basin, ranging from several hundred to over 3,000 km from the tagging area. Distribution patterns were similar across years, suggesting that the principal components of the run were identified. Most spawning fish were clustered in a number of key tributaries, with smaller numbers of fish located in other spatially isolated areas. The fish typically returned to clear water tributaries that were relatively entrenched, had moderate gradients, and were associated with upland areas. Fish were largely absent in lowland reaches characterized by meandering, low gradient, highly alluvial channels often associated with main river floodplains. There was suggestive evidence of mainstem spawning in reaches of the Upper Yukon. The status of fish remaining in other mainstem areas was less certain, and may represent local spawning activity or fish that died while in-transit to upriver areas. Although Chinook salmon spawned throughout the basin, the run was dominated by two regional components (Tanana and Upper Yukon), which annually comprised over 70% of the return. Substantially fewer fish returned to other areas ranging from 2-9% of the return, although the collective contribution of these stocks was appreciable. Most regional returns consisted of several principal stocks and a number of small, spatially isolated populations. Regional and stock composition estimates were similar across years even though differences in run abundance were reported, suggesting that these abundance differences were not related to regional or stock-specific differences. Run timing was relatively compressed compared to rivers in the southern portion of the range, with most stocks passing through the lower river over a 6-week period, ranging from 16 to 38 d. Run timing was generally earlier for stocks traveling farther upriver, although exceptions were noted. Lower basin stocks were primarily later run fish. Pronounced differences were observed in the migration rates (km/d) exhibited by regional stocks. Substantially slower swimming speeds were observed for fish returning to terminal tributaries in the lower basin ranging from 28-40 km/d compared to 52-62 km/d for upper basin stocks. The migratory patterns (migration rates in sequential reaches) of the fish also showed distinct regional differences. Average migration rates through the lower river were remarkably similar for the different stocks, ranging from 57-62 km/d, with most stocks exhibiting a general decline as the fish moved farther upriver. Tanana River stocks displayed a pronounced reduction in swimming speed after leaving the Yukon River main stem, with migration rates declining to 24 km/d on average as the fish approached their terminal tributaries. Conversely, upper basin stocks exhibited a relatively gradual (but variable) overall decline in migration rate even though these fish were traveling substantially greater distances upriver. Average migration rates for upper basin stocks ranged from 43-61 km/d as the fish approached their terminal tributaries. There was substantial variation in the migratory patterns exhibited by individual fish, although these patterns tended to be similar to the patterns exhibited by the regional stocks, particularly as the fish moved farther upriver from the tagging area. The dominant source of variation among fish reflected the average migration rate, with individual fish traveling slower in the lower basin exhibiting consistently slower migration rates as they moved upriver compared to their faster moving counterparts. This migratory pattern was consistent across stocks, and on average explained 74% of the within-stock variation in migration rate represented by the multivariate data. The second source of variation in migration rate reflected a shift in the relative swimming speeds of the individual fish as they progressed upriver. Although movement rates declined for nearly all of the fish during the migration, differences were observed in the pattern of the decline. Fish with faster migration rates in the lower river exhibited a pronounced decline in swimming speed as they moved upriver, whereas fish moving slower in the lower river displayed a more gradual decline in migration rate. On average, this migratory pattern explained 22% of the within-stock variation in migration rate represented by the multivariate data. Most fish (98%) exhibited continuous upriver movements and strong fidelity to the rivers they entered. However a small number of fish (n = 66) deviated from this pattern. Some of these individuals initially passed their final destination and continued upriver for varying distances before reversing direction, swimming back downstream, and entering their terminal tributary. Although most of these excursions were relatively short (< 30 km), there were several instances where fish traveled hundreds of kilometers out of their way. Thirty-four fish tracked to terminal tributaries subsequently left these rivers, and traveled to other terminal tributaries within the basin (n = 31) or were harvested in upriver fisheries (n = 3). Although most of these incidents involved nearby tributaries, major diversions were also observed, with several fish traveling over 300 km to natal rivers after leaving the initial tributary. Chinook salmon returns to the Yukon River typically consisted of a series of distinct and sizable increases in the number fish entering the river over the course of the run, commonly referred to as pulses. A large number of fish (n = 251) were radio tagged over a 4-day period during a pulse in 2003 to provide information on the progression of the pulse as it moved upriver. The time taken by the pulse to move past subsequent upriver locations increased as the fish moved farther upriver from the tagging area, with the fish passing sites located 580 and 800 km upriver over a span of 14 and 21 d, respectively. Although not surprising considering the extensive variation in migration rates observed among individual fish, this finding does suggest that these pulses do not represent cohesive aggregates of fish moving upriver. Unlike the well established methods used to estimate other life history characteristics, the development of quantitative methods for analyzing and modeling fish movements has lagged noticeably behind, due in part to the complexity associated with movement data and (prior to the advent of telemetry) the difficulty of collecting this type of information on free-ranging individuals. Two fundamentally different analytical approaches, hierarchical linear regression models and multivariate ordination, were used during this study to evaluate factors thought to influence the upriver movements of the fish. In spite of the inherent differences, both methods provided strikingly similar results, indicating that the study findings were not dependent on the approach used, and suggesting that the results were plausible based on the information available and the weight of evidence. Both analytical methods had advantages, and provided complementary information. With hierarchical linear models, it was possible to simultaneously evaluate a wide range of explanatory variables (in our case, both biological and environmental), which provided standardized comparisons and simplified the interpretation of the results. Since both fixed and random effects were incorporated in the models, it was possible to account for sources of variation when insufficient information was available to identify the underlining factors – an important consideration since few field studies provide comprehensive data. With multivariate ordination, separate analyzes were needed to examine the relationships between the migration rates and the biotic and physical variables. In addition to being cumbersome, this limitation made it more difficult to compare the relative influence of the different factors and interactions between factors. However, ordination was very useful as an exploratory tool. Although compartmentalized by stock, across fish comparisons were simple and relatively straightforward. Because the explanatory variables were evaluated separately in relation to the ordination score assigned to the fish, it was possible to examine and compare highly correlated variables. Ordination was also able to identify overall patterns within the data and assess the relative importance. While this can be accomplished within the framework of linear regression using mixture models to determine whether multiple distributions exist within the data, the process is much simpler with ordination. The migratory patterns of the fish were influenced by a wide range of factors, with evidentiary support for complex, multi-faceted relationships. Physical features of the basin demonstrated stronger explanatory power, accounting for over 70% of the observed variation in migration rate compared to 18% for the biological characteristics of the fish. Parameter estimates associated with the steepness of the migratory route and remaining distance the fish had to travel to reach their natal rivers were most strongly correlated with migration rate, with consistent relationships observed across stocks. Migration rates were also noticeably slower in extensively braided reaches of the basin. The weaker relationships between migration rate and biotic factors may reflect stabilizing selection on long-distance migrants. Smaller fish exhibited minimally faster swimming speeds on average than larger individuals. This relationship was stronger in highly braided reaches. Run timing was positively related to migration rate for most stocks. Surprisingly, upper basin stocks traveling farther upriver displayed progressively negative relationships, suggesting that late-run fish were moving slower. Ancillary information suggests that this decline may relate to deteriorating fish condition later in the season. Title: Distribution and movements of Chinook salmon, Oncorhynchus tshawytscha, returning to the Yukon River basin Author: Eiler, John H. Chinook salmon, Oncorhynchus tshawytscha, returning to the Yukon River basin and other large river systems in western Alaska have declined dramatically since the late 1990s. This continuing trend has raised concerns over the future status of the returns, and severely impacted commercial and subsistence fisheries within the drainage. Management is further complicated by the mixed-stock composition of the run, the presence of other temporally similar salmon species, and the need to equitably allocate harvests between the numerous fisheries and user groups scattered throughout the basin. Detailed information is needed on Chinook salmon run characteristics to better understand and manage the returns, and facilitate conservation efforts. However, this goal is exacerbated by the massive size and remote nature of the basin, the large number of highly mobile fish, and the compressed timing of the run. To address these challenges, radio telemetry was used to determine the stock composition and spawning distribution of the returns, and the migratory characteristics of the fish. The migratory patterns exhibited by returning salmon provide a number of insights into the status of the run. Since the Yukon River is essentially free-flowing (i.e., not regulated), this study also presented an opportunity to document the distribution and upriver movements of large returns of wild Chinook salmon under natural conditions. During 2002-2004, returning adult Chinook salmon were captured in the lower Yukon River (approximately 300 km upriver from the river mouth), tagged with radio transmitters, and tracked upriver using remote tracking stations located on important migratory routes and major spawning tributaries. Aerial tracking surveys were used to locate fish in spawning areas and between stations. The fish responded well to the capture and handling procedures, with most (2,790, 98%) resuming upriver movements. Although the fish initially displayed a negative tagging response, with slower migration rates observed immediately after release, the duration of this response was relatively short (several days) and less severe as the fish moved upriver. Independent measures indicated that the swimming speeds and timing of the fish upriver from the tagging area were comparable to untagged fish, suggesting that the tagging methods used were relatively benign. Fish returned to spawning areas throughout the basin, ranging from several hundred to over 3,000 km from the tagging area. Distribution patterns were similar across years, suggesting that the principal components of the run were identified. Most spawning fish were clustered in a number of key tributaries, with smaller numbers of fish located in other spatially isolated areas. The fish typically returned to clear water tributaries that were relatively entrenched, had moderate gradients, and were associated with upland areas. Fish were largely absent in lowland reaches characterized by meandering, low gradient, highly alluvial channels often associated with main river floodplains. There was suggestive evidence of mainstem spawning in reaches of the Upper Yukon. The status of fish remaining in other mainstem areas was less certain, and may represent local spawning activity or fish that died while in-transit to upriver areas. Although Chinook salmon spawned throughout the basin, the run was dominated by two regional components (Tanana and Upper Yukon), which annually comprised over 70% of the return. Substantially fewer fish returned to other areas ranging from 2-9% of the return, although the collective contribution of these stocks was appreciable. Most regional returns consisted of several principal stocks and a number of small, spatially isolated populations. Regional and stock composition estimates were similar across years even though differences in run abundance were reported, suggesting that these abundance differences were not related to regional or stock-specific differences. Run timing was relatively compressed compared to rivers in the southern portion of the range, with most stocks passing through the lower river over a 6-week period, ranging from 16 to 38 d. Run timing was generally earlier for stocks traveling farther upriver, although exceptions were noted. Lower basin stocks were primarily later run fish. Pronounced differences were observed in the migration rates (km/d) exhibited by regional stocks. Substantially slower swimming speeds were observed for fish returning to terminal tributaries in the lower basin ranging from 28-40 km/d compared to 52-62 km/d for upper basin stocks. The migratory patterns (migration rates in sequential reaches) of the fish also showed distinct regional differences. Average migration rates through the lower river were remarkably similar for the different stocks, ranging from 57-62 km/d, with most stocks exhibiting a general decline as the fish moved farther upriver. Tanana River stocks displayed a pronounced reduction in swimming speed after leaving the Yukon River main stem, with migration rates declining to 24 km/d on average as the fish approached their terminal tributaries. Conversely, upper basin stocks exhibited a relatively gradual (but variable) overall decline in migration rate even though these fish were traveling substantially greater distances upriver. Average migration rates for upper basin stocks ranged from 43-61 km/d as the fish approached their terminal tributaries. There was substantial variation in the migratory patterns exhibited by individual fish, although these patterns tended to be similar to the patterns exhibited by the regional stocks, particularly as the fish moved farther upriver from the tagging area. The dominant source of variation among fish reflected the average migration rate, with individual fish traveling slower in the lower basin exhibiting consistently slower migration rates as they moved upriver compared to their faster moving counterparts. This migratory pattern was consistent across stocks, and on average explained 74% of the within-stock variation in migration rate represented by the multivariate data. The second source of variation in migration rate reflected a shift in the relative swimming speeds of the individual fish as they progressed upriver. Although movement rates declined for nearly all of the fish during the migration, differences were observed in the pattern of the decline. Fish with faster migration rates in the lower river exhibited a pronounced decline in swimming speed as they moved upriver, whereas fish moving slower in the lower river displayed a more gradual decline in migration rate. On average, this migratory pattern explained 22% of the within-stock variation in migration rate represented by the multivariate data. Most fish (98%) exhibited continuous upriver movements and strong fidelity to the rivers they entered. However a small number of fish (n = 66) deviated from this pattern. Some of these individuals initially passed their final destination and continued upriver for varying distances before reversing direction, swimming back downstream, and entering their terminal tributary. Although most of these excursions were relatively short (< 30 km), there were several instances where fish traveled hundreds of kilometers out of their way. Thirty-four fish tracked to terminal tributaries subsequently left these rivers, and traveled to other terminal tributaries within the basin (n = 31) or were harvested in upriver fisheries (n = 3). Although most of these incidents involved nearby tributaries, major diversions were also observed, with several fish traveling over 300 km to natal rivers after leaving the initial tributary. Chinook salmon returns to the Yukon River typically consisted of a series of distinct and sizable increases in the number fish entering the river over the course of the run, commonly referred to as pulses. A large number of fish (n = 251) were radio tagged over a 4-day period during a pulse in 2003 to provide information on the progression of the pulse as it moved upriver. The time taken by the pulse to move past subsequent upriver locations increased as the fish moved farther upriver from the tagging area, with the fish passing sites located 580 and 800 km upriver over a span of 14 and 21 d, respectively. Although not surprising considering the extensive variation in migration rates observed among individual fish, this finding does suggest that these pulses do not represent cohesive aggregates of fish moving upriver. Unlike the well established methods used to estimate other life history characteristics, the development of quantitative methods for analyzing and modeling fish movements has lagged noticeably behind, due in part to the complexity associated with movement data and (prior to the advent of telemetry) the difficulty of collecting this type of information on free-ranging individuals. Two fundamentally different analytical approaches, hierarchical linear regression models and multivariate ordination, were used during this study to evaluate factors thought to influence the upriver movements of the fish. In spite of the inherent differences, both methods provided strikingly similar results, indicating that the study findings were not dependent on the approach used, and suggesting that the results were plausible based on the information available and the weight of evidence. Both analytical methods had advantages, and provided complementary information. With hierarchical linear models, it was possible to simultaneously evaluate a wide range of explanatory variables (in our case, both biological and environmental), which provided standardized comparisons and simplified the interpretation of the results. Since both fixed and random effects were incorporated in the models, it was possible to account for sources of variation when insufficient information was available to identify the underlining factors – an important consideration since few field studies provide comprehensive data. With multivariate ordination, separate analyzes were needed to examine the relationships between the migration rates and the biotic and physical variables. In addition to being cumbersome, this limitation made it more difficult to compare the relative influence of the different factors and interactions between factors. However, ordination was very useful as an exploratory tool. Although compartmentalized by stock, across fish comparisons were simple and relatively straightforward. Because the explanatory variables were evaluated separately in relation to the ordination score assigned to the fish, it was possible to examine and compare highly correlated variables. Ordination was also able to identify overall patterns within the data and assess the relative importance. While this can be accomplished within the framework of linear regression using mixture models to determine whether multiple distributions exist within the data, the process is much simpler with ordination. The migratory patterns of the fish were influenced by a wide range of factors, with evidentiary support for complex, multi-faceted relationships. Physical features of the basin demonstrated stronger explanatory power, accounting for over 70% of the observed variation in migration rate compared to 18% for the biological characteristics of the fish. Parameter estimates associated with the steepness of the migratory route and remaining distance the fish had to travel to reach their natal rivers were most strongly correlated with migration rate, with consistent relationships observed across stocks. Migration rates were also noticeably slower in extensively braided reaches of the basin. The weaker relationships between migration rate and biotic factors may reflect stabilizing selection on long-distance migrants. Smaller fish exhibited minimally faster swimming speeds on average than larger individuals. This relationship was stronger in highly braided reaches. Run timing was positively related to migration rate for most stocks. Surprisingly, upper basin stocks traveling farther upriver displayed progressively negative relationships, suggesting that late-run fish were moving slower. Ancillary information suggests that this decline may relate to deteriorating fish condition later in the season. Close

• 13124. [Article] The effects of habitat, climate, and Barred Owls on long-term demography of Northern Spotted Owls

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article is copyrighted by Cooper Ornithological ...

  Citation × Citation Citation Abstract Copy Title: The effects of habitat, climate, and Barred Owls on long-term demography of Northern Spotted Owls Author: Franklin, Alan B., Diller, Lowell V., Horn, Rob B., Schwarz, Carl J., McCafferty, Christopher, Gremel, Scott A., Biswell, Brian L., Clark, Darren A., Herter, Dale R., Doherty, Paul F. Jr, Hines, James E., McDonnell, Kevin, Bailey, Larissa, Higley, J. Mark, Yackulic, Charles B., Hobson, Jeremy, Burnham, Kenneth P., Dugger, Katie M., Carlson, Peter C., Clement, Matthew J., Davis, Raymond J., Rockweit, Jeremy, Huyvaert, Kathryn P., Andrews, Lawrence S., Forsman, Eric D., Augustine, Benjamin, Saenz, Jessica, Glenn, Elizabeth M., Blakesley, Jennifer, Olson, Gail S., Ackers, Steven H., McDonald, Trent, Nichols, James D., Green, Adam, Ruiz, Viviana, Sovern, Stan G., White, Gary C., Reid, Janice A. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article is copyrighted by Cooper Ornithological Society and published by Central Ornithology Publication Office. It can be found at: http://www.aoucospubs.org/loi/cond Title: The effects of habitat, climate, and Barred Owls on long-term demography of Northern Spotted Owls Author: Franklin, Alan B., Diller, Lowell V., Horn, Rob B., Schwarz, Carl J., McCafferty, Christopher, Gremel, Scott A., Biswell, Brian L., Clark, Darren A., Herter, Dale R., Doherty, Paul F. Jr, Hines, James E., McDonnell, Kevin, Bailey, Larissa, Higley, J. Mark, Yackulic, Charles B., Hobson, Jeremy, Burnham, Kenneth P., Dugger, Katie M., Carlson, Peter C., Clement, Matthew J., Davis, Raymond J., Rockweit, Jeremy, Huyvaert, Kathryn P., Andrews, Lawrence S., Forsman, Eric D., Augustine, Benjamin, Saenz, Jessica, Glenn, Elizabeth M., Blakesley, Jennifer, Olson, Gail S., Ackers, Steven H., McDonald, Trent, Nichols, James D., Green, Adam, Ruiz, Viviana, Sovern, Stan G., White, Gary C., Reid, Janice A. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article is copyrighted by Cooper Ornithological Society and published by Central Ornithology Publication Office. It can be found at: http://www.aoucospubs.org/loi/cond Close

• 13125. [Article] Contemporary regional forest dynamics in the Pacific Northwest

  Recent climatic warming trends and increases in the frequency and extent of wildfires have prompted much concern regarding the potential for rapid change in the structure and function of forested ecosystems ...

  Citation × Citation Citation Abstract Copy Title: Contemporary regional forest dynamics in the Pacific Northwest Author: Reilly, Matthew J. (Matthew Justin), 1975- Recent climatic warming trends and increases in the frequency and extent of wildfires have prompted much concern regarding the potential for rapid change in the structure and function of forested ecosystems around the world. Episodes of mortality in wildfires and insect outbreaks associated with drought have affected large areas and altered landscapes, but little is known about the cumulative effects of these disturbances at the regional scales. I used data from two different forest inventories in the Pacific Northwest to develop a framework for tracking regional forest dynamics and examine variation in tree mortality rates among vegetation zones that differ in biophysical setting as well as recent and historical disturbance regimes. In the second chapter I developed an empirically based framework for tracking regional forest dynamics using regional inventory data collected from 2001 to 2010. I characterized the major dimensions of forest structure and developed a classification incorporating multiple attributes of forest structure including biomass, size, and density of live trees, the distribution and abundance of dead wood, and the cover of understory vegetation. A single dimension related to live tree biomass accounted for almost half of the variation in a principal components analysis of structural attributes, but dimensions related to density and size of live trees, dead wood, and understory vegetation accounted for as much additional variation. Snags and biomass of dead and downed wood were related to multiple dimensions while understory vegetation acted independent of other dimensions. Results indicated that structural development is more complex than a monotonic accumulation of live biomass and that some components act independently or emerge at multiple stages of structural development. The hierarchical classification reduced the data into three “groups” based on live tree biomass, followed by eleven "classes" that varied in density and size of live trees, and finally twenty-five structural types that differed further in the abundance of dead wood and cover of understory vegetation. Most structural types were geographically widespread but varied in age of dominant trees by vegetation zone indicating that similar structural conditions developed in environments with different biophysical setting, climate, and disturbance/successional histories. Low live biomass structural types (<25 Mg/ha) differed in live tree density and the abundance of live and dead legacies, demonstrating that the variation in early developmental stages depends on the rate of tree establishment and the nature and severity of recent disturbance. Forests in early developmental stages made up less than 20% of most vegetation zones and diverse types with live or dead legacies associated with wildfires were rare. Moderate live biomass structural types (25-99 Mg/ha) represented multiple mid, mature, and late developmental stages, some of which lack analogs in existing conceptual models of structural development such as lower density woodlands with big trees. These structural types included two that have high densities of snags indicative of recent episodes of mortality; together these made up as much as 10% of some dry vegetation zones. Several high live biomass structural types (100->300 Mg/ha) were identified and substantiated the diversity and relative dominance of mature and later developmental stages, particularly in wet vegetation zones. The relative abundance and make up of structural types varied widely by vegetation zone. Most forests in wet vegetation zones had moderate to high live biomass and were in mid and mature developmental stages, while diverse early developmental stage stages were extremely rare. Dry forests had a far greater range of variation in the relative abundance of structural types which is partially attributable to the greater range of climatic conditions they included, but also to the occurrence of recent episodes of mortality associated with wildfires and insects. In the third chapter I examined variation in tree mortality rates using a different regional inventory that occurred from the mid-1990s to the mid-2000s. I compared the distribution of rates among stands in different vegetation zones and stages of structural developmental. I developed a simple framework based on changes in live tree density and mean tree size and examined trends in structural change associated with disturbances at different levels of mortality across all stages of structural development. Most plots were within the range of "background" mortality rates reported in other studies (<1.0 %/yr) and extremely high "stand-replacing" levels of mortality (>25%/yr) were rare. Approximately 30% of plot mortality rates occurred at intermediate levels (>1%/yr and <25%/yr) as result of insects and fire, highlighting the importance of conceptualizing mortality as a continuum as opposed to just “background” or “stand-replacement” to fully represent dynamics at a regional scale. The distributions of mortality differed among many vegetation zones. Levels of mortality were primarily <2.5%/yr in western hemlock, silver fir, and mountain hemlock vegetation zones where fires were rare and insects and pathogens occurred predominantly at endemic levels. Rates were highest in subalpine forests and higher elevation grand fir and Douglas-fir forests as a result of fire and insects. Mortality rates in ponderosa pine, the hottest driest forest vegetation zone, were surprisingly low, and there was little to no mortality in plots with no evidence of disturbance. Mortality rates varied among developmental stages in all vegetation zones but few consistent patterns emerged. Levels of mortality were often lowest in early developmental stages but varied in later stages where they were lowest in wet vegetation zones and highest in subalpine and dry vegetation zones. Application of a simple framework indicated that multiple trajectories of structural change were common at levels of mortality <2.5%/yr, but structural change at higher levels was predominantly associated with a “thinning” trajectory defined by decreases in density and increases in mean tree size. Results indicated that the rate and magnitude of mortality related change during the study period varies widely across the region. Rapid change has occurred in subalpine, grand fir/white fir, Douglas-fir, and ponderosa pine vegetation zones where disturbances such as insects and fire were widespread. However, these disturbances have potentially restored some aspects of historical structure by reducing overall density and increasing the dominance of bigger trees. In western hemlock, silver fir, and mountain hemlock vegetation zones where higher levels of mortality related to disturbances were rare, wildfires have increased landscape diversity by creating diverse early successional habitats and most change was more subtle but may be manifest oevr longer periods if current trends continue. This examination of short-period mortality rates and associated structural change across a broad geographic provides context for understanding trends from localized studies and potential ecological consequences of mortality, but there is still a great deal of uncertainty as to how the effects of a changing climate and disturbance regimes will manifest themselves over longer time scales. This dissertation is one of the first field based assessments of recent forest dynamics at a regional scale. The results of both chapters, each based on a different dataset, told a similar story. The abundance of structural types in various vegetation zones estimated during the mid-2000s was consistent with the cumulative effects of tree mortality during the preceding decade. It was evident that wildfire effects and recent mortality were small relative to the regional extent of the study and have contributed to structural diversity and restoration of historic structure in stands where fire exclusion and past logging has increased total stand density and decreased the dominance of big trees. However, the rate of change and cumulative effects of recent forest dynamics varied widely by geographic location and vegetation zone and there was greater variability and uncertainty regarding the effects of mortality at smaller landscape scales where individual events like large wildfires have the potential to rapidly alter the landscape structure and composition. Assessing this variability and the scales at which trade-offs (e.g. losses of old-growth and creation of diverse early developmental stages) occur will be an important next step in understanding the cumulative ecological effects of recent wildfires and tree mortality on Pacific Northwest forests. Title: Contemporary regional forest dynamics in the Pacific Northwest Author: Reilly, Matthew J. (Matthew Justin), 1975- Recent climatic warming trends and increases in the frequency and extent of wildfires have prompted much concern regarding the potential for rapid change in the structure and function of forested ecosystems around the world. Episodes of mortality in wildfires and insect outbreaks associated with drought have affected large areas and altered landscapes, but little is known about the cumulative effects of these disturbances at the regional scales. I used data from two different forest inventories in the Pacific Northwest to develop a framework for tracking regional forest dynamics and examine variation in tree mortality rates among vegetation zones that differ in biophysical setting as well as recent and historical disturbance regimes. In the second chapter I developed an empirically based framework for tracking regional forest dynamics using regional inventory data collected from 2001 to 2010. I characterized the major dimensions of forest structure and developed a classification incorporating multiple attributes of forest structure including biomass, size, and density of live trees, the distribution and abundance of dead wood, and the cover of understory vegetation. A single dimension related to live tree biomass accounted for almost half of the variation in a principal components analysis of structural attributes, but dimensions related to density and size of live trees, dead wood, and understory vegetation accounted for as much additional variation. Snags and biomass of dead and downed wood were related to multiple dimensions while understory vegetation acted independent of other dimensions. Results indicated that structural development is more complex than a monotonic accumulation of live biomass and that some components act independently or emerge at multiple stages of structural development. The hierarchical classification reduced the data into three “groups” based on live tree biomass, followed by eleven "classes" that varied in density and size of live trees, and finally twenty-five structural types that differed further in the abundance of dead wood and cover of understory vegetation. Most structural types were geographically widespread but varied in age of dominant trees by vegetation zone indicating that similar structural conditions developed in environments with different biophysical setting, climate, and disturbance/successional histories. Low live biomass structural types (<25 Mg/ha) differed in live tree density and the abundance of live and dead legacies, demonstrating that the variation in early developmental stages depends on the rate of tree establishment and the nature and severity of recent disturbance. Forests in early developmental stages made up less than 20% of most vegetation zones and diverse types with live or dead legacies associated with wildfires were rare. Moderate live biomass structural types (25-99 Mg/ha) represented multiple mid, mature, and late developmental stages, some of which lack analogs in existing conceptual models of structural development such as lower density woodlands with big trees. These structural types included two that have high densities of snags indicative of recent episodes of mortality; together these made up as much as 10% of some dry vegetation zones. Several high live biomass structural types (100->300 Mg/ha) were identified and substantiated the diversity and relative dominance of mature and later developmental stages, particularly in wet vegetation zones. The relative abundance and make up of structural types varied widely by vegetation zone. Most forests in wet vegetation zones had moderate to high live biomass and were in mid and mature developmental stages, while diverse early developmental stage stages were extremely rare. Dry forests had a far greater range of variation in the relative abundance of structural types which is partially attributable to the greater range of climatic conditions they included, but also to the occurrence of recent episodes of mortality associated with wildfires and insects. In the third chapter I examined variation in tree mortality rates using a different regional inventory that occurred from the mid-1990s to the mid-2000s. I compared the distribution of rates among stands in different vegetation zones and stages of structural developmental. I developed a simple framework based on changes in live tree density and mean tree size and examined trends in structural change associated with disturbances at different levels of mortality across all stages of structural development. Most plots were within the range of "background" mortality rates reported in other studies (<1.0 %/yr) and extremely high "stand-replacing" levels of mortality (>25%/yr) were rare. Approximately 30% of plot mortality rates occurred at intermediate levels (>1%/yr and <25%/yr) as result of insects and fire, highlighting the importance of conceptualizing mortality as a continuum as opposed to just “background” or “stand-replacement” to fully represent dynamics at a regional scale. The distributions of mortality differed among many vegetation zones. Levels of mortality were primarily <2.5%/yr in western hemlock, silver fir, and mountain hemlock vegetation zones where fires were rare and insects and pathogens occurred predominantly at endemic levels. Rates were highest in subalpine forests and higher elevation grand fir and Douglas-fir forests as a result of fire and insects. Mortality rates in ponderosa pine, the hottest driest forest vegetation zone, were surprisingly low, and there was little to no mortality in plots with no evidence of disturbance. Mortality rates varied among developmental stages in all vegetation zones but few consistent patterns emerged. Levels of mortality were often lowest in early developmental stages but varied in later stages where they were lowest in wet vegetation zones and highest in subalpine and dry vegetation zones. Application of a simple framework indicated that multiple trajectories of structural change were common at levels of mortality <2.5%/yr, but structural change at higher levels was predominantly associated with a “thinning” trajectory defined by decreases in density and increases in mean tree size. Results indicated that the rate and magnitude of mortality related change during the study period varies widely across the region. Rapid change has occurred in subalpine, grand fir/white fir, Douglas-fir, and ponderosa pine vegetation zones where disturbances such as insects and fire were widespread. However, these disturbances have potentially restored some aspects of historical structure by reducing overall density and increasing the dominance of bigger trees. In western hemlock, silver fir, and mountain hemlock vegetation zones where higher levels of mortality related to disturbances were rare, wildfires have increased landscape diversity by creating diverse early successional habitats and most change was more subtle but may be manifest oevr longer periods if current trends continue. This examination of short-period mortality rates and associated structural change across a broad geographic provides context for understanding trends from localized studies and potential ecological consequences of mortality, but there is still a great deal of uncertainty as to how the effects of a changing climate and disturbance regimes will manifest themselves over longer time scales. This dissertation is one of the first field based assessments of recent forest dynamics at a regional scale. The results of both chapters, each based on a different dataset, told a similar story. The abundance of structural types in various vegetation zones estimated during the mid-2000s was consistent with the cumulative effects of tree mortality during the preceding decade. It was evident that wildfire effects and recent mortality were small relative to the regional extent of the study and have contributed to structural diversity and restoration of historic structure in stands where fire exclusion and past logging has increased total stand density and decreased the dominance of big trees. However, the rate of change and cumulative effects of recent forest dynamics varied widely by geographic location and vegetation zone and there was greater variability and uncertainty regarding the effects of mortality at smaller landscape scales where individual events like large wildfires have the potential to rapidly alter the landscape structure and composition. Assessing this variability and the scales at which trade-offs (e.g. losses of old-growth and creation of diverse early developmental stages) occur will be an important next step in understanding the cumulative ecological effects of recent wildfires and tree mortality on Pacific Northwest forests. Close

• 13126. [Article] Trophic cascades and large mammals in the Yellowstone ecosystem

  Reintroduction of wolves to Yellowstone National Park (YNP) in 1995-96 provided a rare opportunity to observe the response of an ecosystem to the return of a top predator, including possible reversal of ...

  Citation × Citation Citation Abstract Copy Title: Trophic cascades and large mammals in the Yellowstone ecosystem Author: Painter, Luke E. Reintroduction of wolves to Yellowstone National Park (YNP) in 1995-96 provided a rare opportunity to observe the response of an ecosystem to the return of a top predator, including possible reversal of decades of decline of aspen, cottonwood, and tall willows suppressed by intensive herbivory on elk winter ranges. To investigate changes in aspen stands in northern Yellowstone since the return of wolves, I compared browsing intensity and heights of young aspen in 87 randomly selected stands in 2012 to similar data collected in the same stands in 1997-98. I also measured the spatial density of elk and bison scat piles as an index to relative population densities, and used annual counts of elk to calculate trends in elk density. In 1998, browsing rates averaged 88%, heights were suppressed, and no tall saplings (≥200 cm) were found in sampling plots. In 2012, browsing rates in 2012 were much lower averaging 44%, and 28% of plots had at least one sapling ≥200 cm, tall enough to escape browsing and therefore more likely to survive to replace dying overstory trees. Heights of young aspen were inversely related to browsing intensity, but not significantly related to leader length, suggesting that differences in height were primarily due to differences in browsing, not factors related to productivity. Aspen recovery was patchy, possibly due in part to locally high elk or bison densities in some parts of the winter range. These results of reduced browsing with increased sapling recruitment were consistent with a trophic cascade from wolves to elk to aspen resulting in a widespread and spatially variable recovery of aspen stands. There was wide variation in browsing intensity and aspen height between sectors of the Yellowstone northern ungulate winter range (northern range). The east sector generally had lower rates of browsing and more stands with tall saplings than the central and west sectors, a pattern that matched recent trends in elk population densities. Only a small minority of stands in the west sector had tall saplings, consistent with higher elk densities in the west. Densities of elk in winter on the northern range recently have been highest in the northwest sector outside the park boundary, where elk benefit from lower wolf densities and milder winters. Aspen stands did not recover at a comparable range-wide elk density when elk were culled in the park in the 1950s and 1960s, suggesting that the influence of wolves may be an important factor in the recent redistribution and reduction of herbivory impacts by elk. To examine the relationship between elk and aspen outside of YNP, I assessed browsing intensity and sapling recruitment in 43 aspen stands in the Shoshone National Forest east of the park, compared to data collected in the same stands in 1997-98. As in northern YNP, results were consistent with a trophic cascade with reduced browsing and increased recruitment of aspen saplings, but aspen recovery was patchy. Elk densities were moderate to high in most of the area, suggesting that the partial aspen recovery may involve a behavioral response to predation or other factors resulting in local variation in browsing impacts. Livestock may also have limited aspen recruitment. Recovery of some aspen stands in the Shoshone National Forest may provide some of the first evidence of a trophic cascade from wolves to elk to aspen outside of a national park, a trophic cascade possibly weakened by the influence of another large herbivore (cattle). Like cattle, bison in northern Yellowstone may have an effect on woody browse plants. Bison have increased in number and may prevent recovery of some aspen stands in places of high bison density. I also examined browsing impacts of bison on willow and cottonwood in the Lamar Valley. To distinguish the effects of bison from those of elk, I compared browsing at different heights on tall willows, below and above the reach of bison. Because elk were absent from the area in summer when bison were present at high density, I also measured browsing that occurred in the summer. I found high rates of summer browsing, and growth of willows and cottonwoods was suppressed in the Lamar Valley. Above the reach of bison (>100 cm), growth was not suppressed and browsing rates were low, suggesting that these plant species have been released from suppression by elk but bison have compensated for some of the reduction in elk browsing. This study provided the first evidence of significant herbivory by bison of woody browse plants in Yellowstone, and revealed some of the complexity of the Yellowstone food web. In summary, these research results support the hypothesis of a trophic cascade resulting from large carnivore restoration and subsequent changes in elk population densities and distribution. The return of wolves may have combined with other factors such as changes in hunting and land ownership, and increased predation by bears, to result in large-scale shifts in the distribution of elk in northern Yellowstone and greatly reduced elk densities in some areas. If these trends continue, the result may be a new alternative state with lower elk densities, and potential for enhanced biodiversity through reduced herbivory of woody browse species. Title: Trophic cascades and large mammals in the Yellowstone ecosystem Author: Painter, Luke E. Reintroduction of wolves to Yellowstone National Park (YNP) in 1995-96 provided a rare opportunity to observe the response of an ecosystem to the return of a top predator, including possible reversal of decades of decline of aspen, cottonwood, and tall willows suppressed by intensive herbivory on elk winter ranges. To investigate changes in aspen stands in northern Yellowstone since the return of wolves, I compared browsing intensity and heights of young aspen in 87 randomly selected stands in 2012 to similar data collected in the same stands in 1997-98. I also measured the spatial density of elk and bison scat piles as an index to relative population densities, and used annual counts of elk to calculate trends in elk density. In 1998, browsing rates averaged 88%, heights were suppressed, and no tall saplings (≥200 cm) were found in sampling plots. In 2012, browsing rates in 2012 were much lower averaging 44%, and 28% of plots had at least one sapling ≥200 cm, tall enough to escape browsing and therefore more likely to survive to replace dying overstory trees. Heights of young aspen were inversely related to browsing intensity, but not significantly related to leader length, suggesting that differences in height were primarily due to differences in browsing, not factors related to productivity. Aspen recovery was patchy, possibly due in part to locally high elk or bison densities in some parts of the winter range. These results of reduced browsing with increased sapling recruitment were consistent with a trophic cascade from wolves to elk to aspen resulting in a widespread and spatially variable recovery of aspen stands. There was wide variation in browsing intensity and aspen height between sectors of the Yellowstone northern ungulate winter range (northern range). The east sector generally had lower rates of browsing and more stands with tall saplings than the central and west sectors, a pattern that matched recent trends in elk population densities. Only a small minority of stands in the west sector had tall saplings, consistent with higher elk densities in the west. Densities of elk in winter on the northern range recently have been highest in the northwest sector outside the park boundary, where elk benefit from lower wolf densities and milder winters. Aspen stands did not recover at a comparable range-wide elk density when elk were culled in the park in the 1950s and 1960s, suggesting that the influence of wolves may be an important factor in the recent redistribution and reduction of herbivory impacts by elk. To examine the relationship between elk and aspen outside of YNP, I assessed browsing intensity and sapling recruitment in 43 aspen stands in the Shoshone National Forest east of the park, compared to data collected in the same stands in 1997-98. As in northern YNP, results were consistent with a trophic cascade with reduced browsing and increased recruitment of aspen saplings, but aspen recovery was patchy. Elk densities were moderate to high in most of the area, suggesting that the partial aspen recovery may involve a behavioral response to predation or other factors resulting in local variation in browsing impacts. Livestock may also have limited aspen recruitment. Recovery of some aspen stands in the Shoshone National Forest may provide some of the first evidence of a trophic cascade from wolves to elk to aspen outside of a national park, a trophic cascade possibly weakened by the influence of another large herbivore (cattle). Like cattle, bison in northern Yellowstone may have an effect on woody browse plants. Bison have increased in number and may prevent recovery of some aspen stands in places of high bison density. I also examined browsing impacts of bison on willow and cottonwood in the Lamar Valley. To distinguish the effects of bison from those of elk, I compared browsing at different heights on tall willows, below and above the reach of bison. Because elk were absent from the area in summer when bison were present at high density, I also measured browsing that occurred in the summer. I found high rates of summer browsing, and growth of willows and cottonwoods was suppressed in the Lamar Valley. Above the reach of bison (>100 cm), growth was not suppressed and browsing rates were low, suggesting that these plant species have been released from suppression by elk but bison have compensated for some of the reduction in elk browsing. This study provided the first evidence of significant herbivory by bison of woody browse plants in Yellowstone, and revealed some of the complexity of the Yellowstone food web. In summary, these research results support the hypothesis of a trophic cascade resulting from large carnivore restoration and subsequent changes in elk population densities and distribution. The return of wolves may have combined with other factors such as changes in hunting and land ownership, and increased predation by bears, to result in large-scale shifts in the distribution of elk in northern Yellowstone and greatly reduced elk densities in some areas. If these trends continue, the result may be a new alternative state with lower elk densities, and potential for enhanced biodiversity through reduced herbivory of woody browse species. Close

• 13127. [Article] Physical-Environmental Effects of Wave and Offshore Wind Energy Extraction: A Synthesis of Recent Oceanographic Research

  The ocean deployment of arrays of Wave Energy Converters (WEC arrays) appears likely in the near future, and deployment of offshore wind turbines has already started. These technologies tap into a potential ...

  Citation × Citation Citation Abstract Copy Title: Physical-Environmental Effects of Wave and Offshore Wind Energy Extraction: A Synthesis of Recent Oceanographic Research Author: Özkan-Haller, Tuba, Haller, Merrick C. The ocean deployment of arrays of Wave Energy Converters (WEC arrays) appears likely in the near future, and deployment of offshore wind turbines has already started. These technologies tap into a potential renewable energy resource but also involve complex systems with uncertain environmental consequences that will likely scale with the size of their ocean footprint. This synthesis talk will concentrate on the potential physical effects of these array technologies. Both WEC arrays and offshore wind farms consist of sizable structures placed in the water column; hence, their mere presence is a potential environmental stressor. Possible effects on the physical environment include wave scattering and wave shadowing; added drag on the coastal current field; modifications to sediment transport (by way of the aforementioned changes to the wave and current forcing); and changes to local sediment characteristics (due to anchors and pilings). In many ways, these effects are similar to those caused by other ocean structures that have been studied for some time (e.g., offshore platforms). However, there are additional potential effects of WECs and wind turbines that require further attention. For example, extraction of wave energy by WECs could have additional environmental consequences. Similarly, offshore wind farms can alter the local wind field, in turn altering locally-generated waves. We will address effects due to wave or wind installations on the wave field, on local ocean circulation, and on sediment transport characteristics. Because WECs partially extract and scatter incident wave energy, they cause significant modifications in the near-field. In fact, if device performance can be optimized at field scales, then by definition the near-field effects will be maximized, i.e., if energy extraction is maximized the potential physical effects of WECs are also maximized. Over the past decade a sizable number of studies have applied theoretical principles using varying assumptions and simplifications to the problem of WEC-wave interactions. Some of these assumptions (e.g., “optimal” motions, monochromatic wave conditions, etc.) have now been shown to be unrealistic, and there has been a convergence toward classes of models that appear to produce reasonable estimates. While recent model studies have managed to bound the problem, significant uncertainties remain. The primary cause for the remaining uncertainties is the lack of observational studies, particularly data sets that provide spatial information about the wave field in the vicinity of in situ devices. Nonetheless, a few studies have undertaken scaled laboratory testing, and these data sets are beginning to lend confidence to the available numerical model results and shed light on the dominant processes. Once near-field effects are understood, far-field effects can be assessed. Far-field effects influence the wave field near beaches, which, in turn, influences the sand transport processes that govern the morphodynamics of the beach face. Fortunately, hydrodynamic modelling of large-scale wave propagation processes in the absence of structures is highly advanced, i.e., if given accurate incident wave conditions in the lee of an installation and bathymetry for the model domain, models can well-simulate local wave conditions, wave-driven currents and sediment transport patterns. Therefore, once near-field WEC/wave dynamics are understood, expanding our understanding to the far-field will be relatively straightforward. Nonetheless, observational studies of far-field beach modifications shoreward of an installation will help to further solidify our understanding of beach behaviour. Offshore wind farms can also potentially influence the local wind field around them. Previous studies of such modifications at land-based wind farm installations serve as a reasonable basis for predictions offshore . Any changes to offshore winds will also influence the local wave field, especially where local winds are the dominant source of waves. Such effects will be minimal near coasts where the local wave climate is dominated by incident swells generated at large distances (e.g., the U.S. West Coast). In contrast, locally generated waves are a more important component of the wave climate on the East Coast of the U.S Modification to ocean currents by an array of structures can be assessed by considering the additional frictional effects (“form” drag) caused of the array. If the drag caused by a dense of array of structures is large, circulation will be altered, which might result in reduced current velocities or the diversion of currents toward an area of less drag. Note that ocean currents already experience drag due to bottom friction; hence, the question hinges on the relative magnitude of the drag induced by structures versus the pre-existing frictional drag. Finally, any near-field modifications to the wave and circulation field (due to either WEC arrays or wind farms) will necessarily result in changes in sediment transport. Any local reduction in flow velocities can result in a reduction of the sediment carrying capacity of circulation leading to sediment accumulation at the site. Small-scale modification to a current will also likely cause bumps and holes around the pilings or anchors. These effects are similar to those observed around existing offshore structures and pilings, and can be accounted for in the design of the structures. Far-field modification of waves and associated changes in wave-induced currents can also result in changes in sediment transport patterns near beaches. Although some recent studies exist, questions regarding far-field effects on beaches are still relatively poorly addressed. Title: Physical-Environmental Effects of Wave and Offshore Wind Energy Extraction: A Synthesis of Recent Oceanographic Research Author: Özkan-Haller, Tuba, Haller, Merrick C. The ocean deployment of arrays of Wave Energy Converters (WEC arrays) appears likely in the near future, and deployment of offshore wind turbines has already started. These technologies tap into a potential renewable energy resource but also involve complex systems with uncertain environmental consequences that will likely scale with the size of their ocean footprint. This synthesis talk will concentrate on the potential physical effects of these array technologies. Both WEC arrays and offshore wind farms consist of sizable structures placed in the water column; hence, their mere presence is a potential environmental stressor. Possible effects on the physical environment include wave scattering and wave shadowing; added drag on the coastal current field; modifications to sediment transport (by way of the aforementioned changes to the wave and current forcing); and changes to local sediment characteristics (due to anchors and pilings). In many ways, these effects are similar to those caused by other ocean structures that have been studied for some time (e.g., offshore platforms). However, there are additional potential effects of WECs and wind turbines that require further attention. For example, extraction of wave energy by WECs could have additional environmental consequences. Similarly, offshore wind farms can alter the local wind field, in turn altering locally-generated waves. We will address effects due to wave or wind installations on the wave field, on local ocean circulation, and on sediment transport characteristics. Because WECs partially extract and scatter incident wave energy, they cause significant modifications in the near-field. In fact, if device performance can be optimized at field scales, then by definition the near-field effects will be maximized, i.e., if energy extraction is maximized the potential physical effects of WECs are also maximized. Over the past decade a sizable number of studies have applied theoretical principles using varying assumptions and simplifications to the problem of WEC-wave interactions. Some of these assumptions (e.g., “optimal” motions, monochromatic wave conditions, etc.) have now been shown to be unrealistic, and there has been a convergence toward classes of models that appear to produce reasonable estimates. While recent model studies have managed to bound the problem, significant uncertainties remain. The primary cause for the remaining uncertainties is the lack of observational studies, particularly data sets that provide spatial information about the wave field in the vicinity of in situ devices. Nonetheless, a few studies have undertaken scaled laboratory testing, and these data sets are beginning to lend confidence to the available numerical model results and shed light on the dominant processes. Once near-field effects are understood, far-field effects can be assessed. Far-field effects influence the wave field near beaches, which, in turn, influences the sand transport processes that govern the morphodynamics of the beach face. Fortunately, hydrodynamic modelling of large-scale wave propagation processes in the absence of structures is highly advanced, i.e., if given accurate incident wave conditions in the lee of an installation and bathymetry for the model domain, models can well-simulate local wave conditions, wave-driven currents and sediment transport patterns. Therefore, once near-field WEC/wave dynamics are understood, expanding our understanding to the far-field will be relatively straightforward. Nonetheless, observational studies of far-field beach modifications shoreward of an installation will help to further solidify our understanding of beach behaviour. Offshore wind farms can also potentially influence the local wind field around them. Previous studies of such modifications at land-based wind farm installations serve as a reasonable basis for predictions offshore . Any changes to offshore winds will also influence the local wave field, especially where local winds are the dominant source of waves. Such effects will be minimal near coasts where the local wave climate is dominated by incident swells generated at large distances (e.g., the U.S. West Coast). In contrast, locally generated waves are a more important component of the wave climate on the East Coast of the U.S Modification to ocean currents by an array of structures can be assessed by considering the additional frictional effects (“form” drag) caused of the array. If the drag caused by a dense of array of structures is large, circulation will be altered, which might result in reduced current velocities or the diversion of currents toward an area of less drag. Note that ocean currents already experience drag due to bottom friction; hence, the question hinges on the relative magnitude of the drag induced by structures versus the pre-existing frictional drag. Finally, any near-field modifications to the wave and circulation field (due to either WEC arrays or wind farms) will necessarily result in changes in sediment transport. Any local reduction in flow velocities can result in a reduction of the sediment carrying capacity of circulation leading to sediment accumulation at the site. Small-scale modification to a current will also likely cause bumps and holes around the pilings or anchors. These effects are similar to those observed around existing offshore structures and pilings, and can be accounted for in the design of the structures. Far-field modification of waves and associated changes in wave-induced currents can also result in changes in sediment transport patterns near beaches. Although some recent studies exist, questions regarding far-field effects on beaches are still relatively poorly addressed. Close

• 13128. [Article] State Funding and Planning Mechanisms to Reduce Greenhouse Gas Emissions from the Transportation Sector

  38 pages

  Citation × Citation Citation Abstract Copy Title: State Funding and Planning Mechanisms to Reduce Greenhouse Gas Emissions from the Transportation Sector Author: Isbell, Rory Year: 2017, 2016 38 pages Title: State Funding and Planning Mechanisms to Reduce Greenhouse Gas Emissions from the Transportation Sector Author: Isbell, Rory Year: 2017, 2016 38 pages Close

• 13129. [Article] Vegetation and Small Mammal Responses to Western Juniper (Juniperus occidentalis) Control in Eastern Oregon

  Shrub-steppe ecosystems of western North America provide habitat for many wildlife species, are important components of public and private rangelands, and offer recreational opportunities for millions ...

  Citation × Citation Citation Abstract Copy Title: Vegetation and Small Mammal Responses to Western Juniper (Juniperus occidentalis) Control in Eastern Oregon Author: Morozumi, Corinne N. Shrub-steppe ecosystems of western North America provide habitat for many wildlife species, are important components of public and private rangelands, and offer recreational opportunities for millions of people. They are some of the most vulnerable ecosystems in the United States and have been altered by human activities such as livestock grazing, active fire suppression, conversion to agriculture, and urbanization of the west. Since the late 1800s woody encroachment of piñon-juniper species has also contributed to the loss of shrub-steppe habitat. Presently, land managers remove woody tree species in order to recover shrub-steppe although it is unclear how responses to these management activities differ due to site-specific conditions and existing woodland development. I studied post juniper-thinning responses in eastern Oregon at a wildlife area important as winter range for mule deer (Odocoileus hemionus). I investigated vegetative responses to western juniper (Juniperus occidentalis) thinning across a woodland development gradient and tested for interactive effects of juniper cutting and cattle exclusion. In addition, I explored plant and small mammal successional dynamics after juniper thinning and examined plant community responses within microhabitats created by the felled trees. I compared vegetative responses to juniper thinning as well as cattle exclusion among sites where juniper were subordinate (Phase I), co-dominant (Phase II), and dominant to shrubs and grasses (Phase III, sensu Miller et al. 2005). At the Phase I site, thinning did not increase herbaceous biomass while thinned plots at the Phase II site had 2.71 times more median herbaceous biomass (99.17% CI: 1.37 to 5.37 times more biomass) than unthinned plots. Conversely, herbaceous biomass at the Phase III juniper woodland site was 0.36 times lower in thinned plots when compared to unthinned plots (99.17% CI: 0.17 to 0.78 times less biomass). Unfortunately, many of the responses were driven by exotic species release. Where juniper were subordinate (Phase I), mean percent cover by exotic grass increased by 24.58 percentage points in thinned plots as compared to unthinned plots (98.30% CI: 0.27 to 48.90 percentage points higher). Thinning at the Phase II site increased mean exotic grass cover by an estimated 28.47 percentage points as compared to mean exotic cover in the same plots before treatment (98.30% CI: 4.15 to 52.79 percentage points higher cover). Median native bunchgrass cover at this site was 5.06 times greater after juniper treatment (99.7% CI: 1.78 to 14.35 times higher percent cover). I found few main or interactive effects of cattle exclosure after one year of treatment. Responses to grazing exclosure may take longer to develop. These results indicate that sites within the wildlife area respond differently to juniper management and that exotic grass control will be key to successful shrub-steppe recovery. In addition, I used a time-since-juniper thinning chronoseries consisting of plots cut in 2008, 2009, 2010, 2012, and an adjacent uncut control to explore how shrub-steppe flora and fauna are responding to juniper treatment through time. Shrub cover and seedling density were low in each plot. I recorded the highest seedling abundance (mean of 0.25 seedlings) in the uncut control plot. Median grass cover in the uncut control was 9.50% while in the most recently treated plot (2012) it was 26.75%. Small mammal relative abundance and diversity was low across all time-since-treatment plots though highest in the plot with the greatest time-since-treatment. Deer mouse (Peromyscus maniculatus) was the most abundant species in all plots and accounted for 70-95% of all unique captures. Least chipmunk (Tamias minimus) were present in the plot with greatest time-since-treatment indicating the potential recovery of key native shrubs since these small mammals perform an important seed dispersal role. I also investigated how potential microhabitats created by the felled juniper might support different plant communities. I assessed plant responses within zones created by 1) the felled tree (canopy zone), 2) the original duff zone, and 3) the between - tree interspace zone. The three zones had different plant community compositions as analyzed multivariately with non-metric multidimensional scaling (NMS). Canopy and duff zones were forb - dominated and had less exotic grass invasion while interspace zones were heavily invested with medusahead (Taeniatherum caput-medusae) and ventenata (Ventenata dubia). Exotic herbaceous productivity was lowest under the standing trees of the control plot and high in the interspace of all plots with juniper thinning. In the 2012 cut plot, grass cover was 27.90 percentage points less in the canopy zone compared to the interspace zone (98.75% CI: 17.64 to 38.16 percentage points less grass cover). In the uncut control, median native biomass was 2.08 times greater under the standing trees compared to the interspace (96.25% CI: 1.09 to 3.97 times more biomass). Results from the time-since-treatment chronoseries indicated that exotic grass dominance might be limiting shrub-steppe recovery. Active restoration of shrubs and native grasses may be necessary to address the dominance of exotic grass after juniper thinning. Positive signs of habitat recovery included small mammal responses though I was unable to calculate population estimates due to plot size. Title: Vegetation and Small Mammal Responses to Western Juniper (Juniperus occidentalis) Control in Eastern Oregon Author: Morozumi, Corinne N. Shrub-steppe ecosystems of western North America provide habitat for many wildlife species, are important components of public and private rangelands, and offer recreational opportunities for millions of people. They are some of the most vulnerable ecosystems in the United States and have been altered by human activities such as livestock grazing, active fire suppression, conversion to agriculture, and urbanization of the west. Since the late 1800s woody encroachment of piñon-juniper species has also contributed to the loss of shrub-steppe habitat. Presently, land managers remove woody tree species in order to recover shrub-steppe although it is unclear how responses to these management activities differ due to site-specific conditions and existing woodland development. I studied post juniper-thinning responses in eastern Oregon at a wildlife area important as winter range for mule deer (Odocoileus hemionus). I investigated vegetative responses to western juniper (Juniperus occidentalis) thinning across a woodland development gradient and tested for interactive effects of juniper cutting and cattle exclusion. In addition, I explored plant and small mammal successional dynamics after juniper thinning and examined plant community responses within microhabitats created by the felled trees. I compared vegetative responses to juniper thinning as well as cattle exclusion among sites where juniper were subordinate (Phase I), co-dominant (Phase II), and dominant to shrubs and grasses (Phase III, sensu Miller et al. 2005). At the Phase I site, thinning did not increase herbaceous biomass while thinned plots at the Phase II site had 2.71 times more median herbaceous biomass (99.17% CI: 1.37 to 5.37 times more biomass) than unthinned plots. Conversely, herbaceous biomass at the Phase III juniper woodland site was 0.36 times lower in thinned plots when compared to unthinned plots (99.17% CI: 0.17 to 0.78 times less biomass). Unfortunately, many of the responses were driven by exotic species release. Where juniper were subordinate (Phase I), mean percent cover by exotic grass increased by 24.58 percentage points in thinned plots as compared to unthinned plots (98.30% CI: 0.27 to 48.90 percentage points higher). Thinning at the Phase II site increased mean exotic grass cover by an estimated 28.47 percentage points as compared to mean exotic cover in the same plots before treatment (98.30% CI: 4.15 to 52.79 percentage points higher cover). Median native bunchgrass cover at this site was 5.06 times greater after juniper treatment (99.7% CI: 1.78 to 14.35 times higher percent cover). I found few main or interactive effects of cattle exclosure after one year of treatment. Responses to grazing exclosure may take longer to develop. These results indicate that sites within the wildlife area respond differently to juniper management and that exotic grass control will be key to successful shrub-steppe recovery. In addition, I used a time-since-juniper thinning chronoseries consisting of plots cut in 2008, 2009, 2010, 2012, and an adjacent uncut control to explore how shrub-steppe flora and fauna are responding to juniper treatment through time. Shrub cover and seedling density were low in each plot. I recorded the highest seedling abundance (mean of 0.25 seedlings) in the uncut control plot. Median grass cover in the uncut control was 9.50% while in the most recently treated plot (2012) it was 26.75%. Small mammal relative abundance and diversity was low across all time-since-treatment plots though highest in the plot with the greatest time-since-treatment. Deer mouse (Peromyscus maniculatus) was the most abundant species in all plots and accounted for 70-95% of all unique captures. Least chipmunk (Tamias minimus) were present in the plot with greatest time-since-treatment indicating the potential recovery of key native shrubs since these small mammals perform an important seed dispersal role. I also investigated how potential microhabitats created by the felled juniper might support different plant communities. I assessed plant responses within zones created by 1) the felled tree (canopy zone), 2) the original duff zone, and 3) the between - tree interspace zone. The three zones had different plant community compositions as analyzed multivariately with non-metric multidimensional scaling (NMS). Canopy and duff zones were forb - dominated and had less exotic grass invasion while interspace zones were heavily invested with medusahead (Taeniatherum caput-medusae) and ventenata (Ventenata dubia). Exotic herbaceous productivity was lowest under the standing trees of the control plot and high in the interspace of all plots with juniper thinning. In the 2012 cut plot, grass cover was 27.90 percentage points less in the canopy zone compared to the interspace zone (98.75% CI: 17.64 to 38.16 percentage points less grass cover). In the uncut control, median native biomass was 2.08 times greater under the standing trees compared to the interspace (96.25% CI: 1.09 to 3.97 times more biomass). Results from the time-since-treatment chronoseries indicated that exotic grass dominance might be limiting shrub-steppe recovery. Active restoration of shrubs and native grasses may be necessary to address the dominance of exotic grass after juniper thinning. Positive signs of habitat recovery included small mammal responses though I was unable to calculate population estimates due to plot size. Close

• 13130. [Article] Egalitarianism and separatism : a history of approaches in the provision of public recreation and leisure service for blacks, 1906-1972

  The purpose of this study was to determine the extent to which the philosophy, administration and implementation of public recreation and leisure service has contributed to the democratization of black Americans ...

  Citation × Citation Citation Abstract Copy Title: Egalitarianism and separatism : a history of approaches in the provision of public recreation and leisure service for blacks, 1906-1972 Author: Murphy, James Frederick The purpose of this study was to determine the extent to which the philosophy, administration and implementation of public recreation and leisure service has contributed to the democratization of black Americans for the period 1906-1972. The study attempted to describe the interplay and connection between the black, subordinated community and the dominant white public administered leisure service organizations and how this relationship has influenced the mode of delivery of public recreation for blacks. The study was undertaken to help the field to more fully understand the consequences of the democratizing effect of recreation and the apparent relationship of continuing public recreation deprivation for black people and urban unrest which does not fit with a consistent pattern of egalitarianism and democracy. Design of the Study The study approach utilized the historical method which mainly involved the data gathering of primary and pertinent secondary material related to the provision of public recreation and leisure service to blacks. The material used in this study was intended to surface important developments, transitions, and approaches to leisure service delivery in order to provide a more sound historical base on which to make future assessments in race relations as it applies to public recreation. A variety of approaches was taken to gather the data analyzed in this study. These approaches included: 1) a comprehensive investigation of related literature; 2) interviews with experts in the field; 3) a personal visit to the library and archives of the National Recreation and Park Association; and 4) the solicitation of informal mail responses from key retired officials of the National Recreation Association and National Recreation and Park Association. The researcher attempted to identify major phases of development in the facilitation of public recreation opportunities for blacks and draw relationships between major social trends as they effected blacks and the recreation movement. These phases of development were summarized in a model of dominant-subordinate relations. The model synthesizes and combines the major societal patterns of dominant-subordinate relations as they relate to blacks and whites, and the patterns of the provision of public recreation and leisure service for blacks during the period 1906-1972. Conclusions From the findings of this study, the following conclusions were drawn: 1. While the recreation movement was initially oriented to meeting the play needs of underprivileged urban youth, the recreation needs of black youth were basically ignored during the first phase (1906-1919) of black/white relations in public recreation. 2. Blacks largely accepted the rationalization for existing pattern of recreation and leisure service during the first phase. Blacks were Left to provide for themselves through their own social agencies- -church, fraternal orders, etc. 3. The traditional egalitarian public recreation service principle of "recreation for all, " was geared primarily to the needs and interests of the dominant white population. 4. The philosophical approach of the recreation movement incorporated the traditional assimilation concept of intergroup relations by supporting local, regional and national dictates in areas of social relations. 5. During the second phase (1920-1954) of black/white relations in public recreation service, special attempts were made to expand recreation facilities and programs for blacks, although primarily on a segregated basis. 6. The leaders of the recreation movement accepted the segregation of blacks as a fact of social relations and attempted to meet their leisure needs through the Bureau of Colored Work and special "colored" divisions of municipal recreation service from 1920 to 1954. 7. Black people have been systematically excluded from participation in. most community sponsored recreation programs because: a) the all-inclusive philosophy of municipal recreation initiated just after World War I moved the focus of leisure service away from delivery to underprivileged youth, and b) the various legal and extra legal discriminatory sanctions in the area of social relations have served to restrict black participation. 8. During the second phase two mutually exclusive paths of segregated organized recreation. service existed. It was during this stage a re-definition of democratic recreation service was employed in the movement and not seen in conflict by its leaders with the "recreation for all" concept of service. 9. The leaders sought to include blacks in the general offerings of the public recreation program, but did not see the separatist paths of public recreation as not conforming to the tenets of egalitarian service principles. Democratic recreation service delivery was adjusted to fit local and regional customs and legal requirements. 10. In actual operation, public recreation and leisure service has reflected the larger pervasive societal patterns of dominant subordinate intergroup relations. 11. The 1954 Supreme Court decision, Brown v. Board of Education, Topeka, Kansas, precipitated the desegregation of public recreation facilities, and eventually led to the improvement of recreational opportunities for black people during the third phase (1955-1965). 12. Attempts to facilitate more equal and inclusive treatment for blacks, particularly since 1954, have been incorporated by most leisure service agencies. 13. Attempts at separate organization, administration and delivery of public recreation during the fourth phase (1966 to present) of black/white relations in public recreation emerged around 1966. These efforts have been consistent with "black power" views for semi-autonomous control over matters of cultural and educational concern. 14. The fourth phase of relations has been characterized by attempts at shared black/white participation in administrative decisions within the total municipal recreation program and community life. 15. Blacks have been almost entirely dependent upon public recreation offerings and leisure service. Recreation is considered a high priority need among the urban poor. 16. The irony of the "recreation for all" approach of public recreation, which has not worked in practice for subordinated blacks, has been the failure of this method to advocate and recognize the particular cultural and social needs and interests of black people. Rioting has resulted from a lack of sensitive dominant white response to the social needs of black ghetto residents and the frustration of black cultural interests. Title: Egalitarianism and separatism : a history of approaches in the provision of public recreation and leisure service for blacks, 1906-1972 Author: Murphy, James Frederick The purpose of this study was to determine the extent to which the philosophy, administration and implementation of public recreation and leisure service has contributed to the democratization of black Americans for the period 1906-1972. The study attempted to describe the interplay and connection between the black, subordinated community and the dominant white public administered leisure service organizations and how this relationship has influenced the mode of delivery of public recreation for blacks. The study was undertaken to help the field to more fully understand the consequences of the democratizing effect of recreation and the apparent relationship of continuing public recreation deprivation for black people and urban unrest which does not fit with a consistent pattern of egalitarianism and democracy. Design of the Study The study approach utilized the historical method which mainly involved the data gathering of primary and pertinent secondary material related to the provision of public recreation and leisure service to blacks. The material used in this study was intended to surface important developments, transitions, and approaches to leisure service delivery in order to provide a more sound historical base on which to make future assessments in race relations as it applies to public recreation. A variety of approaches was taken to gather the data analyzed in this study. These approaches included: 1) a comprehensive investigation of related literature; 2) interviews with experts in the field; 3) a personal visit to the library and archives of the National Recreation and Park Association; and 4) the solicitation of informal mail responses from key retired officials of the National Recreation Association and National Recreation and Park Association. The researcher attempted to identify major phases of development in the facilitation of public recreation opportunities for blacks and draw relationships between major social trends as they effected blacks and the recreation movement. These phases of development were summarized in a model of dominant-subordinate relations. The model synthesizes and combines the major societal patterns of dominant-subordinate relations as they relate to blacks and whites, and the patterns of the provision of public recreation and leisure service for blacks during the period 1906-1972. Conclusions From the findings of this study, the following conclusions were drawn: 1. While the recreation movement was initially oriented to meeting the play needs of underprivileged urban youth, the recreation needs of black youth were basically ignored during the first phase (1906-1919) of black/white relations in public recreation. 2. Blacks largely accepted the rationalization for existing pattern of recreation and leisure service during the first phase. Blacks were Left to provide for themselves through their own social agencies- -church, fraternal orders, etc. 3. The traditional egalitarian public recreation service principle of "recreation for all, " was geared primarily to the needs and interests of the dominant white population. 4. The philosophical approach of the recreation movement incorporated the traditional assimilation concept of intergroup relations by supporting local, regional and national dictates in areas of social relations. 5. During the second phase (1920-1954) of black/white relations in public recreation service, special attempts were made to expand recreation facilities and programs for blacks, although primarily on a segregated basis. 6. The leaders of the recreation movement accepted the segregation of blacks as a fact of social relations and attempted to meet their leisure needs through the Bureau of Colored Work and special "colored" divisions of municipal recreation service from 1920 to 1954. 7. Black people have been systematically excluded from participation in. most community sponsored recreation programs because: a) the all-inclusive philosophy of municipal recreation initiated just after World War I moved the focus of leisure service away from delivery to underprivileged youth, and b) the various legal and extra legal discriminatory sanctions in the area of social relations have served to restrict black participation. 8. During the second phase two mutually exclusive paths of segregated organized recreation. service existed. It was during this stage a re-definition of democratic recreation service was employed in the movement and not seen in conflict by its leaders with the "recreation for all" concept of service. 9. The leaders sought to include blacks in the general offerings of the public recreation program, but did not see the separatist paths of public recreation as not conforming to the tenets of egalitarian service principles. Democratic recreation service delivery was adjusted to fit local and regional customs and legal requirements. 10. In actual operation, public recreation and leisure service has reflected the larger pervasive societal patterns of dominant subordinate intergroup relations. 11. The 1954 Supreme Court decision, Brown v. Board of Education, Topeka, Kansas, precipitated the desegregation of public recreation facilities, and eventually led to the improvement of recreational opportunities for black people during the third phase (1955-1965). 12. Attempts to facilitate more equal and inclusive treatment for blacks, particularly since 1954, have been incorporated by most leisure service agencies. 13. Attempts at separate organization, administration and delivery of public recreation during the fourth phase (1966 to present) of black/white relations in public recreation emerged around 1966. These efforts have been consistent with "black power" views for semi-autonomous control over matters of cultural and educational concern. 14. The fourth phase of relations has been characterized by attempts at shared black/white participation in administrative decisions within the total municipal recreation program and community life. 15. Blacks have been almost entirely dependent upon public recreation offerings and leisure service. Recreation is considered a high priority need among the urban poor. 16. The irony of the "recreation for all" approach of public recreation, which has not worked in practice for subordinated blacks, has been the failure of this method to advocate and recognize the particular cultural and social needs and interests of black people. Rioting has resulted from a lack of sensitive dominant white response to the social needs of black ghetto residents and the frustration of black cultural interests. Close

• 13131. [Article] The physiology ecology and run diversity of adult Pacific lamprey, Entosphenus tridentatus, during the freshwater spawning migration

  Pacific lamprey, Entosphenus tridentatus, have shown recent and rapid declines in abundance. These anadromous fish return to streams where they mature, spawn and die. It has been inferred that Pacific ...

  Citation × Citation Citation Abstract Copy Title: The physiology ecology and run diversity of adult Pacific lamprey, Entosphenus tridentatus, during the freshwater spawning migration Author: Clemens, Benjamin Jacob, 1976- Pacific lamprey, Entosphenus tridentatus, have shown recent and rapid declines in abundance. These anadromous fish return to streams where they mature, spawn and die. It has been inferred that Pacific lamprey enter freshwater and reside for ~ 1 year before spawning. This long exposure to the freshwater environment may affect the plasticity of the maturation process and the migration timing of Pacific lamprey. Diversity in run times and body size has been observed for Pacific lamprey, yet it is unknown if this diversity is induced by the freshwater environment or if it is genetic. My first goal was to describe the maturation and migration characteristics of adult Pacific lamprey during their freshwater migration. My second goal was to use these data to make an estimation of the run diversity in Pacific lamprey. I conducted three complementary studies, in the laboratory and the field, to achieve these goals. I held immature adult lamprey (non-ripe fish that had ceased parasitic feeding in the ocean and had returned to freshwater) in the laboratory at temperatures that mimicked what these fish would experience in the wild, during the summer (mean: 21.8 °C), and another group of lamprey at cooler temperature (mean: 13.6 °C) to compare maturation timing and characteristics. The warm water group of lamprey showed significantly greater proportional decreases in body mass following temperature exposure than fish in the cooler water. All fish exposed to the warm water matured the following spring (8-10 months later) whereas only about half of the fish from the cool water exposure matured. To understand the migration distances and timing of adult Pacific lamprey, I tracked radio-tagged fish throughout the Willamette Basin above Willamette Falls, Oregon, by airplane and recorded their location. Fish migrated primarily during the spring to early summer period before stopping during the remainder of summer, when peak river temperatures (≥ 20°C) occurred. These fish tended to remain stationary through the fall and winter. However, at least a few fish continued to migrate upstream after September. I monitored maturation characteristics of adult Pacific lamprey, over time at Willamette Falls, Oregon and compared these fish with recent migrants collected from the Pacific Ocean as they entered freshwater. The results suggest a unimodal spawn timing between April and June, at water temperatures < 20 °C. Between July and mid-September, as water temperatures peaked at ~ 25 °C, relatively immature fish for both sexes prevailed. Warm summer temperatures coincided with an increase and prevalence of testicular atrophy in males, and I also observed a large die-off of lamprey during this time. The immature fish had maturation stages and phenotypic characteristics similar to recent migrants collected at the mouth of the Klamath River, suggesting that the immature fish at Willamette Falls would spawn the following year, and spawners in any given year may have been recent migrants during the previous year. However there is a temporal overlap in the spring of immature and mature fish, and I found evidence from gonad histology of maturing fish as they entered the river from the ocean, suggesting that a cohort is comprised of recent migrants that spawn within several weeks of entering freshwater, and another cohort is comprised of recent migrants that mature and spawn at least 1 year later. I hypothesize that the recent migrants that would likely spawn shortly after entering freshwater are akin to a winter or "ocean maturing" steelhead, Oncorhynchus mykiss, that optimizes feeding and growth in the open ocean for a few years before entering freshwater to spawn low in the river system shortly afterwards. Alternatively, these lamprey may be similar to coastal cutthroat trout, O. clarki clarki, that feed and grow in the coastal areas of the ocean for a few months before entering freshwater to spawn. There could be other less apparent explanations as well. I also hypothesize that the lamprey that would likely spawn within ~ 1 year of entering freshwater are akin to a "stream maturing" steelhead that foregoes feeding and growth opportunities, enters freshwater during the summer – fall, and accesses spawning grounds to spawn at temperatures that promote evolutionary fitness via successful spawning the following spring. Based on the results of my research, I hypothesize that warm summer temperatures (> 20 °C) can act as a strong selection factor against stream maturing Pacific lamprey in two ways. First, these temperatures may expedite their maturation, while at the same time slowing their migration. If these hypotheses are true, then I predict an uncoupling of spawn timing with optimal habitat characteristics, that would promote fitness, in the upper watershed. Second, summer temperatures may cause gonad atrophy and death prior to spawning. This scenario may select for ocean maturing Pacific lamprey. Title: The physiology ecology and run diversity of adult Pacific lamprey, Entosphenus tridentatus, during the freshwater spawning migration Author: Clemens, Benjamin Jacob, 1976- Pacific lamprey, Entosphenus tridentatus, have shown recent and rapid declines in abundance. These anadromous fish return to streams where they mature, spawn and die. It has been inferred that Pacific lamprey enter freshwater and reside for ~ 1 year before spawning. This long exposure to the freshwater environment may affect the plasticity of the maturation process and the migration timing of Pacific lamprey. Diversity in run times and body size has been observed for Pacific lamprey, yet it is unknown if this diversity is induced by the freshwater environment or if it is genetic. My first goal was to describe the maturation and migration characteristics of adult Pacific lamprey during their freshwater migration. My second goal was to use these data to make an estimation of the run diversity in Pacific lamprey. I conducted three complementary studies, in the laboratory and the field, to achieve these goals. I held immature adult lamprey (non-ripe fish that had ceased parasitic feeding in the ocean and had returned to freshwater) in the laboratory at temperatures that mimicked what these fish would experience in the wild, during the summer (mean: 21.8 °C), and another group of lamprey at cooler temperature (mean: 13.6 °C) to compare maturation timing and characteristics. The warm water group of lamprey showed significantly greater proportional decreases in body mass following temperature exposure than fish in the cooler water. All fish exposed to the warm water matured the following spring (8-10 months later) whereas only about half of the fish from the cool water exposure matured. To understand the migration distances and timing of adult Pacific lamprey, I tracked radio-tagged fish throughout the Willamette Basin above Willamette Falls, Oregon, by airplane and recorded their location. Fish migrated primarily during the spring to early summer period before stopping during the remainder of summer, when peak river temperatures (≥ 20°C) occurred. These fish tended to remain stationary through the fall and winter. However, at least a few fish continued to migrate upstream after September. I monitored maturation characteristics of adult Pacific lamprey, over time at Willamette Falls, Oregon and compared these fish with recent migrants collected from the Pacific Ocean as they entered freshwater. The results suggest a unimodal spawn timing between April and June, at water temperatures < 20 °C. Between July and mid-September, as water temperatures peaked at ~ 25 °C, relatively immature fish for both sexes prevailed. Warm summer temperatures coincided with an increase and prevalence of testicular atrophy in males, and I also observed a large die-off of lamprey during this time. The immature fish had maturation stages and phenotypic characteristics similar to recent migrants collected at the mouth of the Klamath River, suggesting that the immature fish at Willamette Falls would spawn the following year, and spawners in any given year may have been recent migrants during the previous year. However there is a temporal overlap in the spring of immature and mature fish, and I found evidence from gonad histology of maturing fish as they entered the river from the ocean, suggesting that a cohort is comprised of recent migrants that spawn within several weeks of entering freshwater, and another cohort is comprised of recent migrants that mature and spawn at least 1 year later. I hypothesize that the recent migrants that would likely spawn shortly after entering freshwater are akin to a winter or "ocean maturing" steelhead, Oncorhynchus mykiss, that optimizes feeding and growth in the open ocean for a few years before entering freshwater to spawn low in the river system shortly afterwards. Alternatively, these lamprey may be similar to coastal cutthroat trout, O. clarki clarki, that feed and grow in the coastal areas of the ocean for a few months before entering freshwater to spawn. There could be other less apparent explanations as well. I also hypothesize that the lamprey that would likely spawn within ~ 1 year of entering freshwater are akin to a "stream maturing" steelhead that foregoes feeding and growth opportunities, enters freshwater during the summer – fall, and accesses spawning grounds to spawn at temperatures that promote evolutionary fitness via successful spawning the following spring. Based on the results of my research, I hypothesize that warm summer temperatures (> 20 °C) can act as a strong selection factor against stream maturing Pacific lamprey in two ways. First, these temperatures may expedite their maturation, while at the same time slowing their migration. If these hypotheses are true, then I predict an uncoupling of spawn timing with optimal habitat characteristics, that would promote fitness, in the upper watershed. Second, summer temperatures may cause gonad atrophy and death prior to spawning. This scenario may select for ocean maturing Pacific lamprey. Close

• 13132. [Article] Reproductive implications of parasitic infections and immune challenges in garter snakes

  Parasitic infections and immune challenges can affect host reproductive fitness and, ultimately, the evolution of host populations in a myriad of ways. The fitness implications of parasitic infections ...

  Citation × Citation Citation Abstract Copy Title: Reproductive implications of parasitic infections and immune challenges in garter snakes Author: Uhrig, Emily J. Parasitic infections and immune challenges can affect host reproductive fitness and, ultimately, the evolution of host populations in a myriad of ways. The fitness implications of parasitic infections range from increased host mortality to subtle changes in reproductive investment. From alterations of behaviors, sexual signaling, and competitive ability to changes in gamete production and fertilization success, it is clear that parasites are capable of mediating sexual selection and influencing host reproductive fitness even without altering mortality. The mechanisms underlying fitness effects highlight the complexity of the host-parasite relationship which involves immune responses as well as a range of other, often interactive, physiological processes within the host. In some instances, it is not the direct effect of parasites per se, but rather the hosts' responses to infection that mediate fitness consequences. This dissertation presents studies designed to elucidate the implications of parasitism and immune responses for the reproductive fitness of garter snakes (genus Thamnophis). In chapter 2, "Alaria mesocercariae in the tails of red-sided garter snakes: evidence for parasite-mediated caudectomy", I focus on the histopathological changes associated with a trematode (Alaria sp.) infecting the tails of red-sided garter snakes (T. sirtalis parietalis). My results demonstrate that Alaria mesocercariae occur in high density within the tail tissue of both male and female snakes with as many as 2,000 mesocercariae in a single tail; infection prevalence was 100% in the snakes I examined. I found no evidence of intersexual variation in pathological changes or infection densities. For both sexes, external pathological manifestations include swelling of the tail while, internally, the aggregation of mesocercariae leads to the formation of mucus-filled pseudocysts and damage of muscle tissue. In severe cases, the extent of tissue destruction appeared to weaken the connection of the tail to the rest of the body, a condition that would facilitate tail breakage, which in turn negatively affects the snake's fitness by impairing mating success. From the parasite's perspective, tail breakage is likely beneficial by facilitating its transmission to subsequent hosts in its life cycle. Alaria sp. are not the only parasites commonly infecting garter snakes and in chapter 3, "Patterns in parasitism: interspecific and interpopulational variation in helminth assemblages and their reproductive fitness correlates in garter snakes", I broaden our investigation to include a suite of helminth parasites common in the garter snakes of Manitoba, Canada. My results demonstrate that helminth assemblages of two garter snake species (red-sided garter snakes, T. sirtalis parietalis, and plains garter snakes, T. radix) include Lechriorchis trematodes and Rhabdias nematodes in the lung, Alaria mesocercariae in the tail, and diplostomid trematode metacercariae in the visceral fat; red-sided garter snakes also had gastrointestinal cestodes. Helminth assemblages varied, mainly in terms of parasite density, among populations of red-sided garter snakes and between red-sided and plains garter snakes, but it is unclear whether this variation is due simply to diet-based differences in parasite exposure or whether variation in parasite resistance may have a role. Notably, for plains garter snakes and one red-sided garter snake population I found helminth densities to be predictive of male fitness correlates, namely body condition, testes mass, and sperm counts. Thus, parasitism in garter snakes clearly has important implications for reproductive fitness beyond just influencing tail loss. These results highlight the importance of considering more than a single parasite or single fitness correlate when exploring host-parasite relationships. The consequences of parasitic infections may arise simply through the activation of the host’s immune system rather than the presence of parasites. Thus, in chapter 4, "Changes in reproductive investment and hormone levels in response to an acute immune challenge", I use lipopolysaccharide (LPS) to assess immune-reproductive tradeoffs of male red-sided garter snakes during the breeding season. As LPS is non-pathogenic, I was able to assess the fitness implications of the immune activation itself. My results showed that males depress courtship behaviors and mating success when faced with a single acute immune challenge. For LPS-treated males that did mate, copulatory plug mass was significantly lower compared to controls, while sperm counts did not differ between treatments. This result likely reflects the dissociated breeding pattern of these snakes as spermatogenesis occurs outside the breeding season and, thus, sperm stores were already in place prior to the immune challenge whereas plug material is produced during the breeding season. Further, the LPS treatment was correlated with increased plasma levels of corticosterone, which were 1.8 times higher in LPS-treated males compared to controls, and decreased levels of androgens, which, in LPS-treated males, were only one third as high as androgen levels in control males. Thus, the observed immune-reproduction tradeoff appeared to be hormonally-mediated. Indeed, the low breeding season androgen levels characteristic of this dissociated breeder may have relaxed testosterone-mediated immunosuppression and so facilitate immune-induced suppression of reproductive behaviors. The results of this study highlight the influence of host life history on the consequences of immune activation and also emphasize the complex interactions between the immune, reproductive and endocrine systems. In chapter 5, "Implications of repeated immune challenges in a capital breeder with prolonged hibernation", I again utilized LPS as a means of investigating the implications of immune activation. In this study, I administered a series of LPS injections to male and mated female snakes throughout the summer feeding season, and, for males, into the autumn. Females give birth during the summer and males undergo testicular recrudescence and spermatogenesis during summer and into autumn so these seasons represent important reproductive periods for red-sided garter snakes. Also, as capital breeders, it is during the summer feeding season that snakes of both sexes accumulate the resources upon which they will rely throughout hibernation and the subsequent breeding season. For the most part, my results did not demonstrate clear immune-reproductive tradeoffs. It appears that the absence of tradeoffs may be due to immune-challenged males and gravid female compensating for the immune challenge and maintaining reproductive processes by increasing their food intake, which was not limited during the study. Indeed, LPS-treated gravid females actually had more offspring per litter compared to gravid control females, suggesting that the immune challenge led to greater investment in offspring. In contrast to gravid females, non-gravid females treated with LPS exhibited reduced food intake which may reflect a survival strategy as anorexia during infections tends to be beneficial for survival. Interestingly, the increased food consumption of males did not translate into greater fat stores, but rather higher liver masses which may be indicative of immunopathological changes which should be explored in future studies. Title: Reproductive implications of parasitic infections and immune challenges in garter snakes Author: Uhrig, Emily J. Parasitic infections and immune challenges can affect host reproductive fitness and, ultimately, the evolution of host populations in a myriad of ways. The fitness implications of parasitic infections range from increased host mortality to subtle changes in reproductive investment. From alterations of behaviors, sexual signaling, and competitive ability to changes in gamete production and fertilization success, it is clear that parasites are capable of mediating sexual selection and influencing host reproductive fitness even without altering mortality. The mechanisms underlying fitness effects highlight the complexity of the host-parasite relationship which involves immune responses as well as a range of other, often interactive, physiological processes within the host. In some instances, it is not the direct effect of parasites per se, but rather the hosts' responses to infection that mediate fitness consequences. This dissertation presents studies designed to elucidate the implications of parasitism and immune responses for the reproductive fitness of garter snakes (genus Thamnophis). In chapter 2, "Alaria mesocercariae in the tails of red-sided garter snakes: evidence for parasite-mediated caudectomy", I focus on the histopathological changes associated with a trematode (Alaria sp.) infecting the tails of red-sided garter snakes (T. sirtalis parietalis). My results demonstrate that Alaria mesocercariae occur in high density within the tail tissue of both male and female snakes with as many as 2,000 mesocercariae in a single tail; infection prevalence was 100% in the snakes I examined. I found no evidence of intersexual variation in pathological changes or infection densities. For both sexes, external pathological manifestations include swelling of the tail while, internally, the aggregation of mesocercariae leads to the formation of mucus-filled pseudocysts and damage of muscle tissue. In severe cases, the extent of tissue destruction appeared to weaken the connection of the tail to the rest of the body, a condition that would facilitate tail breakage, which in turn negatively affects the snake's fitness by impairing mating success. From the parasite's perspective, tail breakage is likely beneficial by facilitating its transmission to subsequent hosts in its life cycle. Alaria sp. are not the only parasites commonly infecting garter snakes and in chapter 3, "Patterns in parasitism: interspecific and interpopulational variation in helminth assemblages and their reproductive fitness correlates in garter snakes", I broaden our investigation to include a suite of helminth parasites common in the garter snakes of Manitoba, Canada. My results demonstrate that helminth assemblages of two garter snake species (red-sided garter snakes, T. sirtalis parietalis, and plains garter snakes, T. radix) include Lechriorchis trematodes and Rhabdias nematodes in the lung, Alaria mesocercariae in the tail, and diplostomid trematode metacercariae in the visceral fat; red-sided garter snakes also had gastrointestinal cestodes. Helminth assemblages varied, mainly in terms of parasite density, among populations of red-sided garter snakes and between red-sided and plains garter snakes, but it is unclear whether this variation is due simply to diet-based differences in parasite exposure or whether variation in parasite resistance may have a role. Notably, for plains garter snakes and one red-sided garter snake population I found helminth densities to be predictive of male fitness correlates, namely body condition, testes mass, and sperm counts. Thus, parasitism in garter snakes clearly has important implications for reproductive fitness beyond just influencing tail loss. These results highlight the importance of considering more than a single parasite or single fitness correlate when exploring host-parasite relationships. The consequences of parasitic infections may arise simply through the activation of the host’s immune system rather than the presence of parasites. Thus, in chapter 4, "Changes in reproductive investment and hormone levels in response to an acute immune challenge", I use lipopolysaccharide (LPS) to assess immune-reproductive tradeoffs of male red-sided garter snakes during the breeding season. As LPS is non-pathogenic, I was able to assess the fitness implications of the immune activation itself. My results showed that males depress courtship behaviors and mating success when faced with a single acute immune challenge. For LPS-treated males that did mate, copulatory plug mass was significantly lower compared to controls, while sperm counts did not differ between treatments. This result likely reflects the dissociated breeding pattern of these snakes as spermatogenesis occurs outside the breeding season and, thus, sperm stores were already in place prior to the immune challenge whereas plug material is produced during the breeding season. Further, the LPS treatment was correlated with increased plasma levels of corticosterone, which were 1.8 times higher in LPS-treated males compared to controls, and decreased levels of androgens, which, in LPS-treated males, were only one third as high as androgen levels in control males. Thus, the observed immune-reproduction tradeoff appeared to be hormonally-mediated. Indeed, the low breeding season androgen levels characteristic of this dissociated breeder may have relaxed testosterone-mediated immunosuppression and so facilitate immune-induced suppression of reproductive behaviors. The results of this study highlight the influence of host life history on the consequences of immune activation and also emphasize the complex interactions between the immune, reproductive and endocrine systems. In chapter 5, "Implications of repeated immune challenges in a capital breeder with prolonged hibernation", I again utilized LPS as a means of investigating the implications of immune activation. In this study, I administered a series of LPS injections to male and mated female snakes throughout the summer feeding season, and, for males, into the autumn. Females give birth during the summer and males undergo testicular recrudescence and spermatogenesis during summer and into autumn so these seasons represent important reproductive periods for red-sided garter snakes. Also, as capital breeders, it is during the summer feeding season that snakes of both sexes accumulate the resources upon which they will rely throughout hibernation and the subsequent breeding season. For the most part, my results did not demonstrate clear immune-reproductive tradeoffs. It appears that the absence of tradeoffs may be due to immune-challenged males and gravid female compensating for the immune challenge and maintaining reproductive processes by increasing their food intake, which was not limited during the study. Indeed, LPS-treated gravid females actually had more offspring per litter compared to gravid control females, suggesting that the immune challenge led to greater investment in offspring. In contrast to gravid females, non-gravid females treated with LPS exhibited reduced food intake which may reflect a survival strategy as anorexia during infections tends to be beneficial for survival. Interestingly, the increased food consumption of males did not translate into greater fat stores, but rather higher liver masses which may be indicative of immunopathological changes which should be explored in future studies. Close

• 13133. [Article] Mixed-Severity Fire Effects on Biological Legacies and Vegetation Response in Pseudotsuga Forests of Western Oregon's Central Cascades, USA

  Mixed-severity fire occurrence is increasingly recognized in Pseudotsuga forests of the Pacific Northwest, but questions remain about how tree mortality varies, and forest structure is altered, across ...

  Citation × Citation Citation Abstract Copy Title: Mixed-Severity Fire Effects on Biological Legacies and Vegetation Response in Pseudotsuga Forests of Western Oregon's Central Cascades, USA Author: Dunn, Christopher J. Mixed-severity fire occurrence is increasingly recognized in Pseudotsuga forests of the Pacific Northwest, but questions remain about how tree mortality varies, and forest structure is altered, across the disturbance gradient observed in these fires. Therefore, we sampled live and dead biological legacies at 45 one ha plots, with four 0.10 ha nested plots, stratified across an unburned, low, moderate and high-severity fire gradient. We used severity estimates based on differenced Normalized Burn Ratio (dNBR), and captured a disturbance gradient, but plots in our low-severity class underestimated fire effects because of misclassification or delayed mortality. We estimated probability of mortality for shade-intolerant (Douglas-fir, incense-cedar, sugar pine) and shade-tolerant (western hemlock, western redcedar, true fir) trees from 5,079 sampled trees and snags. The probability of mortality was higher for shade-tolerant species across all fire-severity classes, and decreased with increasing DBH except for western hemlock. Only large, shade-intolerant trees survived high-severity fire. Post-fire snag fall and fragmentation were estimated from 2,746 sampled snags and logs. The probability of snag fall decreased with increasing DBH for all species, and was positively correlated with fire severity, except for Douglas-fir that had a higher probability following low-severity fire. Snag fragmentation was positively correlated with DBH and fire severity for all species. We also estimated the coefficient of variation within- and among-plots by fire severity class, as well as across all sampled conditions. Structural attributes varied more within- than among-plots, likely a result of increasing sub-hectare patchy mortality as fire intensity increased. Although vertical and horizontal structural diversity increased at sub-hectare scales, the coefficient of variation was highest for all structural attributes when compared across all fire severity classes. Therefore, the range of fire effects observed in mixed-severity fires may be functionally important in creating structural complexity across landscapes, which is an important attribute of old-growth forests in the Pacific Northwest. Understory vegetation response to mixed-severity fires has not been characterized for these forests even though the majority of vegetation diversity is found in these vegetation layers. Therefore, we sampled forest structure (1000 m² circular plots) and understory vegetation (100 m² plots) at 168 collocated plots stratified across unburned, low, moderate and high-severity conditions 10 years (Tiller Complex) and 22 years (Warner Fire) post-fire. We focused on shrub species, but sampled forbs, graminoids, ferns and moss as functional groups. Offsite colonization and fire stimulated soil seedbanks increased the total species richness from 23 to 46. The life-history strategies of residual and colonizing species resulted in three dominant species response-curves to the magnitude of disturbance: 1) 'disturbance-sensitive', when relative abundance was highest in unburned plots and continued to decline with increasing fire severity, 2) 'disturbance-stimulated', when relative abundance was highest following low or moderate-severity fire and 3) 'disturbance-amplified', when relative abundance increased with increasing fire severity. Residual and colonizing species assemblages promoted five or six distinct understory communities, dominantly driven by legacy tree basal area rather than the proportion of basal area killed. Understory communities were rarely associated with one disturbance severity class as fire refugia, variation in overstory and understory fire severity, and compensatory conditions offset fire effects. Early-seral habitats were the most different from unburned forests, but were not the only post-fire conditions important across these burned landscapes. Interactions among live and dead forest structures following low or moderate-severity fire, and the vegetation response to these conditions, are also unique to the post-fire landscape and likely important for various wildlife species. Therefore, if ecological forestry paradigms focus dominantly on creating old-growth structure or early-seral habitats, they might exclude important conditions that contribute to the landscape structural complexity created by mixed-severity fires. Additionally, tree regeneration response to mixed-severity fires has not been characterized for these forests even though they offer insight into one aspect of the resilience of these ecosystems to disturbance. Therefore, we sampled forest structure (1000 m² circular plots) and regeneration dynamics (100 m² plots) at 168 collocated plots stratified across unburned, low, moderate and high-severity conditions 10 years (Tiller Complex) and 22 years (Warner Fire) post-fire. The largest marginal increase in tree mortality (stems ha⁻¹) occurred between unburned and low-severity fires, given preferential mortality of small trees and shade-tolerant species, but basal area mortality had the largest marginal increase moving from moderate to high-severity. Pairwise comparisons of legacy tree basal area between low and moderate-severity weren’t as significant as other comparisons, but did capture a gradient of increasing fire effects. Quadratic mean diameter and canopy base height were positively correlated with fire severity as incrementally larger trees were killed and canopy ascension followed. Regeneration density increased regardless of severity, relative to unburned forests (median density of 1,384 trees ha⁻¹), but the highest median density (16,220 trees ha⁻¹) followed low-severity fire at the Tiller Complex and moderate-severity fire (14,472 trees ha⁻¹) at Warner Fire. Plot-level average species richness was highest following these same fire severity classes, supporting the Intermediate Disturbance Hypothesis. Statistically distinct regeneration communities occurred across the fire severity gradient at both fire sites. The relative abundance of shade-tolerant tree species decreased as fire severity increased, except for a divergent response following stand-initiation at the Warner Fire. While divergent successional pathways were evident within a couple decades following stand-initiation, low or moderate-severity fires also modified successional trajectories and may be the most functionally important disturbance magnitude because it has the greatest potential to increase compositional and structural diversity. Incorporating mixed-severity fire effects into landscape management of Pseudotsuga forests could increase structural complexity at stand and landscape-scales. Title: Mixed-Severity Fire Effects on Biological Legacies and Vegetation Response in Pseudotsuga Forests of Western Oregon's Central Cascades, USA Author: Dunn, Christopher J. Mixed-severity fire occurrence is increasingly recognized in Pseudotsuga forests of the Pacific Northwest, but questions remain about how tree mortality varies, and forest structure is altered, across the disturbance gradient observed in these fires. Therefore, we sampled live and dead biological legacies at 45 one ha plots, with four 0.10 ha nested plots, stratified across an unburned, low, moderate and high-severity fire gradient. We used severity estimates based on differenced Normalized Burn Ratio (dNBR), and captured a disturbance gradient, but plots in our low-severity class underestimated fire effects because of misclassification or delayed mortality. We estimated probability of mortality for shade-intolerant (Douglas-fir, incense-cedar, sugar pine) and shade-tolerant (western hemlock, western redcedar, true fir) trees from 5,079 sampled trees and snags. The probability of mortality was higher for shade-tolerant species across all fire-severity classes, and decreased with increasing DBH except for western hemlock. Only large, shade-intolerant trees survived high-severity fire. Post-fire snag fall and fragmentation were estimated from 2,746 sampled snags and logs. The probability of snag fall decreased with increasing DBH for all species, and was positively correlated with fire severity, except for Douglas-fir that had a higher probability following low-severity fire. Snag fragmentation was positively correlated with DBH and fire severity for all species. We also estimated the coefficient of variation within- and among-plots by fire severity class, as well as across all sampled conditions. Structural attributes varied more within- than among-plots, likely a result of increasing sub-hectare patchy mortality as fire intensity increased. Although vertical and horizontal structural diversity increased at sub-hectare scales, the coefficient of variation was highest for all structural attributes when compared across all fire severity classes. Therefore, the range of fire effects observed in mixed-severity fires may be functionally important in creating structural complexity across landscapes, which is an important attribute of old-growth forests in the Pacific Northwest. Understory vegetation response to mixed-severity fires has not been characterized for these forests even though the majority of vegetation diversity is found in these vegetation layers. Therefore, we sampled forest structure (1000 m² circular plots) and understory vegetation (100 m² plots) at 168 collocated plots stratified across unburned, low, moderate and high-severity conditions 10 years (Tiller Complex) and 22 years (Warner Fire) post-fire. We focused on shrub species, but sampled forbs, graminoids, ferns and moss as functional groups. Offsite colonization and fire stimulated soil seedbanks increased the total species richness from 23 to 46. The life-history strategies of residual and colonizing species resulted in three dominant species response-curves to the magnitude of disturbance: 1) 'disturbance-sensitive', when relative abundance was highest in unburned plots and continued to decline with increasing fire severity, 2) 'disturbance-stimulated', when relative abundance was highest following low or moderate-severity fire and 3) 'disturbance-amplified', when relative abundance increased with increasing fire severity. Residual and colonizing species assemblages promoted five or six distinct understory communities, dominantly driven by legacy tree basal area rather than the proportion of basal area killed. Understory communities were rarely associated with one disturbance severity class as fire refugia, variation in overstory and understory fire severity, and compensatory conditions offset fire effects. Early-seral habitats were the most different from unburned forests, but were not the only post-fire conditions important across these burned landscapes. Interactions among live and dead forest structures following low or moderate-severity fire, and the vegetation response to these conditions, are also unique to the post-fire landscape and likely important for various wildlife species. Therefore, if ecological forestry paradigms focus dominantly on creating old-growth structure or early-seral habitats, they might exclude important conditions that contribute to the landscape structural complexity created by mixed-severity fires. Additionally, tree regeneration response to mixed-severity fires has not been characterized for these forests even though they offer insight into one aspect of the resilience of these ecosystems to disturbance. Therefore, we sampled forest structure (1000 m² circular plots) and regeneration dynamics (100 m² plots) at 168 collocated plots stratified across unburned, low, moderate and high-severity conditions 10 years (Tiller Complex) and 22 years (Warner Fire) post-fire. The largest marginal increase in tree mortality (stems ha⁻¹) occurred between unburned and low-severity fires, given preferential mortality of small trees and shade-tolerant species, but basal area mortality had the largest marginal increase moving from moderate to high-severity. Pairwise comparisons of legacy tree basal area between low and moderate-severity weren’t as significant as other comparisons, but did capture a gradient of increasing fire effects. Quadratic mean diameter and canopy base height were positively correlated with fire severity as incrementally larger trees were killed and canopy ascension followed. Regeneration density increased regardless of severity, relative to unburned forests (median density of 1,384 trees ha⁻¹), but the highest median density (16,220 trees ha⁻¹) followed low-severity fire at the Tiller Complex and moderate-severity fire (14,472 trees ha⁻¹) at Warner Fire. Plot-level average species richness was highest following these same fire severity classes, supporting the Intermediate Disturbance Hypothesis. Statistically distinct regeneration communities occurred across the fire severity gradient at both fire sites. The relative abundance of shade-tolerant tree species decreased as fire severity increased, except for a divergent response following stand-initiation at the Warner Fire. While divergent successional pathways were evident within a couple decades following stand-initiation, low or moderate-severity fires also modified successional trajectories and may be the most functionally important disturbance magnitude because it has the greatest potential to increase compositional and structural diversity. Incorporating mixed-severity fire effects into landscape management of Pseudotsuga forests could increase structural complexity at stand and landscape-scales. Close

• 13134. [Article] Mixed-conifer forests of central Oregon : structure, composition, history of establishment, and growth

  The structure and composition of mixed-conifer forest (MCF) in central Oregon has been altered by fire exclusion and logging. The resulting increased density, spatial contagion, and loss of fire resistant ...

  Citation × Citation Citation Abstract Copy Title: Mixed-conifer forests of central Oregon : structure, composition, history of establishment, and growth Author: Merschel, Andrew G. The structure and composition of mixed-conifer forest (MCF) in central Oregon has been altered by fire exclusion and logging. The resulting increased density, spatial contagion, and loss of fire resistant trees decrease the resiliency of this ecosystem to fire, drought, and insects. The historical and current composition and structure of MCF are characterized by steep environmental gradients and a complex mixed-severity fire regime. This inherent variation makes it difficult to determine the magnitude of anthropogenic effects and set objectives for restoration and management. As a result, there is a lack of consensus regarding how MCF should be managed and restored across the landscape. My primary research objectives were to: (1) Characterize the current structure and composition of MCF and how these vary with environmental setting; and (2) Characterize establishment and tree growth patterns in MCF in different environmental settings. To address these objectives, I collected field data on structure and composition and increment cores across a range of environmental conditions in MCF of the eastern Cascades and Ochoco Mountains. I used cluster analysis to identify four stand types based on structure and composition in the eastern Cascades study area and four analogous types in the Ochoco Mountains study area. Variation in understory composition and the presence of large diameter shade tolerant species distinguish each type. Stand types occupied distinct environmental settings along a climatic gradient of increasing precipitation and elevation. At relatively dry PIPO sites understories were dominated by ponderosa pine. At wetter PIPO/PSME and PIPO ABGC sites understories were dominated by shade tolerant species, but ponderosa pine was dominant in the overstory. At the coolest and wettest PIPO/PSME/ABGC sites understories were dominated by grand fir and shade tolerant species were common in the overstory. In the eastern Cascades current density of all live trees and snags was 432, 461, 570, 372 trees per hectare (TPH) for the four stand types identified. Stand types in the drier Ochoco Mountains were currently less dense at 279, 304, 212, and 307 TPH. Current MCF densities in both areas are 2-3 times higher than densities estimated for the late 19th and early 20th centuries from other studies in those two areas. Reconstruction of cuts in each stand type indicates that the density of large diameter ponderosa pine has been reduced by approximately 50% in all stand types in both study regions. Age histograms demonstrate that current density and composition of MCF stand types is a product of abrupt increases in tree establishment following fire exclusion in the late 19th century. The number of trees established increased after 1900 in all stand types, but the timing and composition of changes in establishment varied with climate. At dry PIPO sites increases in establishment were delayed until the 1920s and 1930s and were composed of ponderosa pine. At PIPO/PSME and PIPO/ABGC sites with intermediate precipitation, establishment was dominated by ponderosa pine prior to 1900, but after 1900 establishment was dominated by a large pulse of Douglas-fir and grand fir. At the wettest PIPO/PSME/ABGC there was less evidence of changes in structure and composition over time. My results indicate that compared to dry pine and dry-mixed conifer sites, relatively productive moist mixed-conifer sites were characterized by large changes in structure and composition. Such sites could be considered more ecologically altered by lack of fire than drier forest types that had high fire frequencies but slower rates of stand development and less plant community change. Radial growth patterns of cored ponderosa pines differed between the eastern Cascades and Ochoco Mountains. In the eastern Cascades mean growth rates and variance decreased during favorable climatic periods after 1900. This is likely related to increased competition, and provides evidence that current stand density lacks a temporal analog in the 18th and 19th centuries. Sensitivity of growth to climate and harvest suggest competition for water in the denser forest of the eastern Cascades, and indicates thinning will increase the diameter growth rate of large old pines. In the Ochoco Mountains, ponderosa pine tree growth was less responsive to climate prior to fire exclusion in the late 1800s, and growth did not respond to fire events. This suggests competition among trees was historically low in this region. After fire exclusion growth became more responsive to wet and dry climatic cycles, which may indicate that increased density and competition made trees more responsive to climate variability. Patterns of slow and fast growth appeared to differ between study regions and likely differ at the sub-regional scale. Further analysis of the relationship between growth and climate in different environmental settings is needed to distinguish where stand development has been modified by disruption of fire regimes. Title: Mixed-conifer forests of central Oregon : structure, composition, history of establishment, and growth Author: Merschel, Andrew G. The structure and composition of mixed-conifer forest (MCF) in central Oregon has been altered by fire exclusion and logging. The resulting increased density, spatial contagion, and loss of fire resistant trees decrease the resiliency of this ecosystem to fire, drought, and insects. The historical and current composition and structure of MCF are characterized by steep environmental gradients and a complex mixed-severity fire regime. This inherent variation makes it difficult to determine the magnitude of anthropogenic effects and set objectives for restoration and management. As a result, there is a lack of consensus regarding how MCF should be managed and restored across the landscape. My primary research objectives were to: (1) Characterize the current structure and composition of MCF and how these vary with environmental setting; and (2) Characterize establishment and tree growth patterns in MCF in different environmental settings. To address these objectives, I collected field data on structure and composition and increment cores across a range of environmental conditions in MCF of the eastern Cascades and Ochoco Mountains. I used cluster analysis to identify four stand types based on structure and composition in the eastern Cascades study area and four analogous types in the Ochoco Mountains study area. Variation in understory composition and the presence of large diameter shade tolerant species distinguish each type. Stand types occupied distinct environmental settings along a climatic gradient of increasing precipitation and elevation. At relatively dry PIPO sites understories were dominated by ponderosa pine. At wetter PIPO/PSME and PIPO ABGC sites understories were dominated by shade tolerant species, but ponderosa pine was dominant in the overstory. At the coolest and wettest PIPO/PSME/ABGC sites understories were dominated by grand fir and shade tolerant species were common in the overstory. In the eastern Cascades current density of all live trees and snags was 432, 461, 570, 372 trees per hectare (TPH) for the four stand types identified. Stand types in the drier Ochoco Mountains were currently less dense at 279, 304, 212, and 307 TPH. Current MCF densities in both areas are 2-3 times higher than densities estimated for the late 19th and early 20th centuries from other studies in those two areas. Reconstruction of cuts in each stand type indicates that the density of large diameter ponderosa pine has been reduced by approximately 50% in all stand types in both study regions. Age histograms demonstrate that current density and composition of MCF stand types is a product of abrupt increases in tree establishment following fire exclusion in the late 19th century. The number of trees established increased after 1900 in all stand types, but the timing and composition of changes in establishment varied with climate. At dry PIPO sites increases in establishment were delayed until the 1920s and 1930s and were composed of ponderosa pine. At PIPO/PSME and PIPO/ABGC sites with intermediate precipitation, establishment was dominated by ponderosa pine prior to 1900, but after 1900 establishment was dominated by a large pulse of Douglas-fir and grand fir. At the wettest PIPO/PSME/ABGC there was less evidence of changes in structure and composition over time. My results indicate that compared to dry pine and dry-mixed conifer sites, relatively productive moist mixed-conifer sites were characterized by large changes in structure and composition. Such sites could be considered more ecologically altered by lack of fire than drier forest types that had high fire frequencies but slower rates of stand development and less plant community change. Radial growth patterns of cored ponderosa pines differed between the eastern Cascades and Ochoco Mountains. In the eastern Cascades mean growth rates and variance decreased during favorable climatic periods after 1900. This is likely related to increased competition, and provides evidence that current stand density lacks a temporal analog in the 18th and 19th centuries. Sensitivity of growth to climate and harvest suggest competition for water in the denser forest of the eastern Cascades, and indicates thinning will increase the diameter growth rate of large old pines. In the Ochoco Mountains, ponderosa pine tree growth was less responsive to climate prior to fire exclusion in the late 1800s, and growth did not respond to fire events. This suggests competition among trees was historically low in this region. After fire exclusion growth became more responsive to wet and dry climatic cycles, which may indicate that increased density and competition made trees more responsive to climate variability. Patterns of slow and fast growth appeared to differ between study regions and likely differ at the sub-regional scale. Further analysis of the relationship between growth and climate in different environmental settings is needed to distinguish where stand development has been modified by disruption of fire regimes. Close

• 13135. [Article] Genesis of some soils in the central western Cascades of Oregon

  Soils representative of several landscape units in the H. J. Andrews Experimental Forest, Western Cascade Range, were sampled, analyzed, and tentatively classified. Genetic inferences were drawn relating ...

  Citation × Citation Citation Abstract Copy Title: Genesis of some soils in the central western Cascades of Oregon Author: Brown, R. B. Soils representative of several landscape units in the H. J. Andrews Experimental Forest, Western Cascade Range, were sampled, analyzed, and tentatively classified. Genetic inferences were drawn relating soils to landscape position and other factors of soil formation. Descriptive information and nutrient capital data were provided to support ecosystem modelling efforts by the Coniferous Forest Biome study group of the U. S./International Biological Program (IBP). To meet the "nutrient capital" requirements of IBP, and to gain insight particularly into the effects of coarse fragments on soil genesis, a volumetric approach was used. Soil organic matter, total N, extractable P, exchangeable cations, free Fe oxides, and cation exchange capacity were expressed in terms of weight or equivalents per unit volume of "whole soil," defined as organic and mineral fine earth components plus pore space plus coarse fragments. The various entities, in grams or equivalents per liter of whole soil, were observed as to their variation with depth. Additional calculations showed levels of the various entities per surface meter ³ of whole soil. Soil temperature data from several sites within the Andrews Forest showed the mesic-frigid soil temperature regime boundary to fall at about the 600 m (2, 000 ft) elevation on south slopes and at about the 450 m (1, 500 ft) elevation on north slopes. The frigidcryic boundary apparently was above the 1, 500 m (4,900 ft) elevation in the Andrews Forest. A sequence of three fluvial and two colluvial soils ranging in elevation from 440 to 460 m was studied in conjunction with concurrent IBP investigations into the geomorphic history of the area The soil on a floodplain adjacent to Lookout Creek, in the sandy-skeletal, mixed, mesic family of Fluventic Hapludolls, was between 500 and 7, 000 yrs in age. The adjacent stream terrace soil, in the loamyskeletal, mixed, mesic family of Fluventic Dystrochrepts, was > 7, 000 yrs old as evidenced Mazama pumice erposi tE-; on or near the surface of the terrace. Volumetric analysis suggested that the floodplain soil had a mollic epipedon largely by virtue of its high content of coarse fragments. The coarse fragments caused a concentration of soil organic matter and recycled cations into a smaller volume of fine earth as compared with the terrace soil, which was lower in coarse fragments. An alluvial-colluvial fan emanated from an adjacent slope and lapped onto the terrace. The soil in this fan was a member of the Fluventic Eutrochrepts, loamy-skeletal, mixed, mesic. It was high in base status and moderately high in clay content, apparently because the southeast-facing source area for parent material here had experienced only shallow weathering and minimal leaching. Across Lookout Creek from these landscape units was a remnant of a high colluvial terrace emanating from a northwest-facing watershed. At the crest of this fan remnant the soil was a member of the loamy-skeletal, mixed, mesic family of Fluventic Dystrochrepts with a distinct layer of Mazama pumice at the 75 to 85 cm depth. This terrace is cut by the watershed stream, which has deposited a comparatively well sorted fan. Soils are in the coarseloamy, mixed, mesic family of Fluventic Dystrochrepts, Eight landscape units in longitudinal and transverse crosssections of upper McRae Creek valley, ranging in elevation from 800 to 1, 200 m, were chosen to study upland soil genesis. Proceeding up the valley, stage of profile development appeared to decrease, indicating a series of depositional events. Soils varied from Eutric Glossoboralfs, fine, mixed on the lowermost surface to Fluventic Dystrochrepts, fine-loamy, mixed, frigid on the next higher surface, to Fluventic Dystrochrepts, loamy-skeletal, mixed, frigid on the next higher surface, to Typic Haplumbrepts, loamy-skeletal, mixed, frigid on the backslope at the valley headwall. The two lowermost soils contrasted markedly with the two uppermost soils, being lower in content of organic matter and N, and higher in base status and clay content. The upper two soils, typical of upper valley bottom and sideslope soils in the region, were extremely low in exchangeable bases and base saturation as measured at pH 7. Compared with the two lower soils, however, these upper soils had relatively high soil: water pH values and relatively small drops in pH from soil:water to soil :KCI measurement. This may be an indication that the upper soils were higher in amorphous content. Greater pH-dependent-CEC would have caused the upper soils to exhibit unrealistically high CEO s--and thus low base saturations--when measured at pH 7. A topoclimosequence of soils on north, east (saddle), and south-facing landscape units with a single parent rock lithology was studied in the transverse valley transect. All three soils were placed tentatively in the Andic Dystrochrepts. The north-facing soil was in a medial - skeletal, frigid family, was the deepest to bedrock ( > 1 1/2 m), aria had the freshest coarse fragments of the three soils. The saddle and south-facing soils were in medial-skeletal, frigid and medial, frigid families, respectively. They were shallow ( <1 m) to saprolite bedrock, with well weathered coarse fragments in the regolith, demonstrating shallower, but apparently more intense weathering on the more exposed sites. These more exposed soils were darker in color than the north-facing soil. Soil organic matter levels were not strikingly different among the three soils. Soil N levels were significantly higher in the south-facing soil than in the east and north-facing soils. Levels of exchangeable bases, while low, were not as low in these three soils as in the upper valley bottom and backslope soils. Saprolite horizons had higher base saturations than overlying horizons. Title: Genesis of some soils in the central western Cascades of Oregon Author: Brown, R. B. Soils representative of several landscape units in the H. J. Andrews Experimental Forest, Western Cascade Range, were sampled, analyzed, and tentatively classified. Genetic inferences were drawn relating soils to landscape position and other factors of soil formation. Descriptive information and nutrient capital data were provided to support ecosystem modelling efforts by the Coniferous Forest Biome study group of the U. S./International Biological Program (IBP). To meet the "nutrient capital" requirements of IBP, and to gain insight particularly into the effects of coarse fragments on soil genesis, a volumetric approach was used. Soil organic matter, total N, extractable P, exchangeable cations, free Fe oxides, and cation exchange capacity were expressed in terms of weight or equivalents per unit volume of "whole soil," defined as organic and mineral fine earth components plus pore space plus coarse fragments. The various entities, in grams or equivalents per liter of whole soil, were observed as to their variation with depth. Additional calculations showed levels of the various entities per surface meter ³ of whole soil. Soil temperature data from several sites within the Andrews Forest showed the mesic-frigid soil temperature regime boundary to fall at about the 600 m (2, 000 ft) elevation on south slopes and at about the 450 m (1, 500 ft) elevation on north slopes. The frigidcryic boundary apparently was above the 1, 500 m (4,900 ft) elevation in the Andrews Forest. A sequence of three fluvial and two colluvial soils ranging in elevation from 440 to 460 m was studied in conjunction with concurrent IBP investigations into the geomorphic history of the area The soil on a floodplain adjacent to Lookout Creek, in the sandy-skeletal, mixed, mesic family of Fluventic Hapludolls, was between 500 and 7, 000 yrs in age. The adjacent stream terrace soil, in the loamyskeletal, mixed, mesic family of Fluventic Dystrochrepts, was > 7, 000 yrs old as evidenced Mazama pumice erposi tE-; on or near the surface of the terrace. Volumetric analysis suggested that the floodplain soil had a mollic epipedon largely by virtue of its high content of coarse fragments. The coarse fragments caused a concentration of soil organic matter and recycled cations into a smaller volume of fine earth as compared with the terrace soil, which was lower in coarse fragments. An alluvial-colluvial fan emanated from an adjacent slope and lapped onto the terrace. The soil in this fan was a member of the Fluventic Eutrochrepts, loamy-skeletal, mixed, mesic. It was high in base status and moderately high in clay content, apparently because the southeast-facing source area for parent material here had experienced only shallow weathering and minimal leaching. Across Lookout Creek from these landscape units was a remnant of a high colluvial terrace emanating from a northwest-facing watershed. At the crest of this fan remnant the soil was a member of the loamy-skeletal, mixed, mesic family of Fluventic Dystrochrepts with a distinct layer of Mazama pumice at the 75 to 85 cm depth. This terrace is cut by the watershed stream, which has deposited a comparatively well sorted fan. Soils are in the coarseloamy, mixed, mesic family of Fluventic Dystrochrepts, Eight landscape units in longitudinal and transverse crosssections of upper McRae Creek valley, ranging in elevation from 800 to 1, 200 m, were chosen to study upland soil genesis. Proceeding up the valley, stage of profile development appeared to decrease, indicating a series of depositional events. Soils varied from Eutric Glossoboralfs, fine, mixed on the lowermost surface to Fluventic Dystrochrepts, fine-loamy, mixed, frigid on the next higher surface, to Fluventic Dystrochrepts, loamy-skeletal, mixed, frigid on the next higher surface, to Typic Haplumbrepts, loamy-skeletal, mixed, frigid on the backslope at the valley headwall. The two lowermost soils contrasted markedly with the two uppermost soils, being lower in content of organic matter and N, and higher in base status and clay content. The upper two soils, typical of upper valley bottom and sideslope soils in the region, were extremely low in exchangeable bases and base saturation as measured at pH 7. Compared with the two lower soils, however, these upper soils had relatively high soil: water pH values and relatively small drops in pH from soil:water to soil :KCI measurement. This may be an indication that the upper soils were higher in amorphous content. Greater pH-dependent-CEC would have caused the upper soils to exhibit unrealistically high CEO s--and thus low base saturations--when measured at pH 7. A topoclimosequence of soils on north, east (saddle), and south-facing landscape units with a single parent rock lithology was studied in the transverse valley transect. All three soils were placed tentatively in the Andic Dystrochrepts. The north-facing soil was in a medial - skeletal, frigid family, was the deepest to bedrock ( > 1 1/2 m), aria had the freshest coarse fragments of the three soils. The saddle and south-facing soils were in medial-skeletal, frigid and medial, frigid families, respectively. They were shallow ( <1 m) to saprolite bedrock, with well weathered coarse fragments in the regolith, demonstrating shallower, but apparently more intense weathering on the more exposed sites. These more exposed soils were darker in color than the north-facing soil. Soil organic matter levels were not strikingly different among the three soils. Soil N levels were significantly higher in the south-facing soil than in the east and north-facing soils. Levels of exchangeable bases, while low, were not as low in these three soils as in the upper valley bottom and backslope soils. Saprolite horizons had higher base saturations than overlying horizons. Close

• 13136. [Article] Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Harvest Monitoring - 2016 Annual Progress Report

  Abstract -- The Imnaha and Grande Ronde River spring Chinook hatchery programs are components of the Lower Snake River Compensation Plan (LSRCP), funded through the U.S. Fish and Wildlife Service (USFWS), ...

  Citation × Citation Citation Abstract Copy Title: Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Harvest Monitoring - 2016 Annual Progress Report Abstract -- The Imnaha and Grande Ronde River spring Chinook hatchery programs are components of the Lower Snake River Compensation Plan (LSRCP), funded through the U.S. Fish and Wildlife Service (USFWS), developed to mitigate for wild fish production lost as a result of construction of the four lower Snake River dams. Hatchery Chinook and steelhead smolts in the Snake River basin are produced at LSRCP hatcheries in Washington, Idaho and Oregon. Subsequent adult returns are meant to provide tribal and recreational (sport) fisheries and, in some cases, enhance natural spawner numbers. The Oregon Department of Fish and Wildlife (ODFW) initiated the Imnaha and Grande Ronde spring Chinook hatchery program in 1982 under the LSRCP. Subsequent program management has been coordinated between ODFW, the Confederated Tribes of the Umatilla Indian Reservation (CTUIR), and the Nez Perce Tribe (NPT). The Imnaha and Grande Ronde River hatchery programs are comprised of five components, each with smolt acclimation and adult collection facilities located on the Imnaha River, upper Grande Ronde River, Lookingglass and Catherine Creeks, and the Lostine River. The Lostine River program interacts with natural production within the broader Wallowa-Lostine population unit. Other hatchery program components are discrete to specific populations indicated. The Lookingglass Creek portion of the program focuses on reintroduction of spring Chinook to that stream and targets the release of 250,000 smolts, annually. Each of the four remaining program components integrates natural-origin fish returning to each respective tributary into production. Smolt release goals, developed to meet LSRCP mitigation responsibilities; include 490,000 for the Imnaha, 250,000 for the Lostine and upper Grande Ronde rivers, and 150,000 for Catherine Creek. Fisheries that target returns to the Imnaha and Grande Ronde hatchery programs are guided by Fishery Management and Evaluation Plans (FMEP), approved by NOAA fisheries under limit 4 of the final 4(d) rule of the Endangered Species Act (ODFW 2011, ODFW and WDFW 2012). The objective of the FMEP is to provide recreational fishing opportunities and related benefits derived from harvest of Imnaha and Grande Ronde basin hatchery-origin spring Chinook salmon in Oregon and Washington in a manner that supports the continued survival and future recovery of natural-origin Chinook salmon. Each respective FMEP utilizes a management framework for harvest of adipose-clipped, hatchery-origin Snake River spring/summer Chinook salmon using abundance-based sliding scales to set annual fishery impacts. Fisheries are prescribed maximum impact rates for both direct and incidental mortality of natural-origin adult salmon in sport and tribal fisheries. Impacts are assessed for each population in relation to critical and minimum abundance thresholds (MAT) as described by the Interior Columbia Technical Recovery Team (ICTRT 2007). Population designations for the Imnaha and Grande Ronde Basins are listed in Table 1, and are based upon an analysis of Chinook salmon life history traits, distribution, abundance, and productivity, and geographical and ecological characteristics of the landscape within the Snake River Spring/Summer Chinook Salmon ESU (McElhany et al. 2000). The abundance-based harvest rate schedule for Imnaha and Grande Ronde Basin fisheries to be shared by all fishing entities in the basin as described in Table 2. Harvest is not considered when hatchery run size does not exceed the number of adults identified for broodstock and supplementation needs as described by sliding scale management plans set for each population’s hatchery program. Surplus is generally defined as the adult hatchery run projection less hatchery adults needed for broodstock. This approach limits sport harvest during years when wild fish runs are below MAT and hatchery fish runs are of similar size. In addition, near the lower end of the harvest rate scale, fisheries are not implemented until the allowable hatchery fish harvest exceeds 20 fish due to potential to over harvest within a single week. Fishery impacts to listed Snake River spring/summer Chinook salmon are assessed on a collective basis (i.e., the sum of recreational and tribal fisheries) by NOAA fisheries. However, the coordination of impact amongst states and tribes is a key component of executing conservation-based fisheries in the Imnaha and Grande Ronde Basins. Co-managers within each basin have developed, and implement annually, an impact sharing agreement that is described in Table 3. Within each fishery scenario, this agreement provides tribal fisheries more of the natural-origin impacts to reflect the non-selective nature of traditional fishing techniques. Recreational fisheries are provided a larger portion of the hatchery harvest such that all available impacts (hatchery and natural collectively) are shared equally (Table 3). Recreational fisheries administered by the states limit harvest (retention) of spring/summer Chinook hatchery-origin salmon with a clipped adipose fin (as evidenced by a healed scar). All salmon with an intact adipose fin (natural-origin) must be released back to the water. Therefore, incidental mortality impacts occur from catch and release of unclipped Snake River spring/summer Chinook salmon in fisheries targeting adipose-clipped hatchery Chinook salmon, and/or from the illegal retention of unclipped fish. It is generally assumed throughout the Columbia River Basin that the mortality rate resulting from the catch and release of salmon in fisheries is 10%. However, for Lookingglass Creek comanagers, with concurrence from NOAA fisheries, assume a slightly lower rate of 7.5% (ODFW and WDFW 2012). As stated in the FMEP, fisheries are adjusted or terminated when the total ESA take limit identified in Table 2 and 3 has been reached. Therefore, once fisheries are initiated regular monitoring is required to ensure consistency with co-manager agreements and FMEP requirements. The objective of this LSRCP project was to conduct statistical creel surveys to determine spring Chinook and steelhead ESA impact levels, harvest and release rates, and to inform decisions regarding fishery status in the Imnaha and Grande Ronde Basins in 2016. In this report, we describe creel surveys conducted and estimates of angler effort, catch, and harvest. In addition we compare these estimates in relation to estimates of natural and hatchery-origin returns to each population to assess consistency with prescribed impacts under FMEP guidelines. Lower Snake River Compensation Plan (LSRCP) ODFW Title: Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Harvest Monitoring - 2016 Annual Progress Report Abstract -- The Imnaha and Grande Ronde River spring Chinook hatchery programs are components of the Lower Snake River Compensation Plan (LSRCP), funded through the U.S. Fish and Wildlife Service (USFWS), developed to mitigate for wild fish production lost as a result of construction of the four lower Snake River dams. Hatchery Chinook and steelhead smolts in the Snake River basin are produced at LSRCP hatcheries in Washington, Idaho and Oregon. Subsequent adult returns are meant to provide tribal and recreational (sport) fisheries and, in some cases, enhance natural spawner numbers. The Oregon Department of Fish and Wildlife (ODFW) initiated the Imnaha and Grande Ronde spring Chinook hatchery program in 1982 under the LSRCP. Subsequent program management has been coordinated between ODFW, the Confederated Tribes of the Umatilla Indian Reservation (CTUIR), and the Nez Perce Tribe (NPT). The Imnaha and Grande Ronde River hatchery programs are comprised of five components, each with smolt acclimation and adult collection facilities located on the Imnaha River, upper Grande Ronde River, Lookingglass and Catherine Creeks, and the Lostine River. The Lostine River program interacts with natural production within the broader Wallowa-Lostine population unit. Other hatchery program components are discrete to specific populations indicated. The Lookingglass Creek portion of the program focuses on reintroduction of spring Chinook to that stream and targets the release of 250,000 smolts, annually. Each of the four remaining program components integrates natural-origin fish returning to each respective tributary into production. Smolt release goals, developed to meet LSRCP mitigation responsibilities; include 490,000 for the Imnaha, 250,000 for the Lostine and upper Grande Ronde rivers, and 150,000 for Catherine Creek. Fisheries that target returns to the Imnaha and Grande Ronde hatchery programs are guided by Fishery Management and Evaluation Plans (FMEP), approved by NOAA fisheries under limit 4 of the final 4(d) rule of the Endangered Species Act (ODFW 2011, ODFW and WDFW 2012). The objective of the FMEP is to provide recreational fishing opportunities and related benefits derived from harvest of Imnaha and Grande Ronde basin hatchery-origin spring Chinook salmon in Oregon and Washington in a manner that supports the continued survival and future recovery of natural-origin Chinook salmon. Each respective FMEP utilizes a management framework for harvest of adipose-clipped, hatchery-origin Snake River spring/summer Chinook salmon using abundance-based sliding scales to set annual fishery impacts. Fisheries are prescribed maximum impact rates for both direct and incidental mortality of natural-origin adult salmon in sport and tribal fisheries. Impacts are assessed for each population in relation to critical and minimum abundance thresholds (MAT) as described by the Interior Columbia Technical Recovery Team (ICTRT 2007). Population designations for the Imnaha and Grande Ronde Basins are listed in Table 1, and are based upon an analysis of Chinook salmon life history traits, distribution, abundance, and productivity, and geographical and ecological characteristics of the landscape within the Snake River Spring/Summer Chinook Salmon ESU (McElhany et al. 2000). The abundance-based harvest rate schedule for Imnaha and Grande Ronde Basin fisheries to be shared by all fishing entities in the basin as described in Table 2. Harvest is not considered when hatchery run size does not exceed the number of adults identified for broodstock and supplementation needs as described by sliding scale management plans set for each population’s hatchery program. Surplus is generally defined as the adult hatchery run projection less hatchery adults needed for broodstock. This approach limits sport harvest during years when wild fish runs are below MAT and hatchery fish runs are of similar size. In addition, near the lower end of the harvest rate scale, fisheries are not implemented until the allowable hatchery fish harvest exceeds 20 fish due to potential to over harvest within a single week. Fishery impacts to listed Snake River spring/summer Chinook salmon are assessed on a collective basis (i.e., the sum of recreational and tribal fisheries) by NOAA fisheries. However, the coordination of impact amongst states and tribes is a key component of executing conservation-based fisheries in the Imnaha and Grande Ronde Basins. Co-managers within each basin have developed, and implement annually, an impact sharing agreement that is described in Table 3. Within each fishery scenario, this agreement provides tribal fisheries more of the natural-origin impacts to reflect the non-selective nature of traditional fishing techniques. Recreational fisheries are provided a larger portion of the hatchery harvest such that all available impacts (hatchery and natural collectively) are shared equally (Table 3). Recreational fisheries administered by the states limit harvest (retention) of spring/summer Chinook hatchery-origin salmon with a clipped adipose fin (as evidenced by a healed scar). All salmon with an intact adipose fin (natural-origin) must be released back to the water. Therefore, incidental mortality impacts occur from catch and release of unclipped Snake River spring/summer Chinook salmon in fisheries targeting adipose-clipped hatchery Chinook salmon, and/or from the illegal retention of unclipped fish. It is generally assumed throughout the Columbia River Basin that the mortality rate resulting from the catch and release of salmon in fisheries is 10%. However, for Lookingglass Creek comanagers, with concurrence from NOAA fisheries, assume a slightly lower rate of 7.5% (ODFW and WDFW 2012). As stated in the FMEP, fisheries are adjusted or terminated when the total ESA take limit identified in Table 2 and 3 has been reached. Therefore, once fisheries are initiated regular monitoring is required to ensure consistency with co-manager agreements and FMEP requirements. The objective of this LSRCP project was to conduct statistical creel surveys to determine spring Chinook and steelhead ESA impact levels, harvest and release rates, and to inform decisions regarding fishery status in the Imnaha and Grande Ronde Basins in 2016. In this report, we describe creel surveys conducted and estimates of angler effort, catch, and harvest. In addition we compare these estimates in relation to estimates of natural and hatchery-origin returns to each population to assess consistency with prescribed impacts under FMEP guidelines. Lower Snake River Compensation Plan (LSRCP) ODFW Close

• 13137. [Article] Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Harvest Monitoring - 2015 Annual Progress Report

  Abstract -- The Imnaha and Grande Ronde River spring Chinook hatchery programs are components of the Lower Snake River Compensation Plan (LSRCP), funded through the U.S. Fish and Wildlife Service (USFWS), ...

  Citation × Citation Citation Abstract Copy Title: Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Harvest Monitoring - 2015 Annual Progress Report Abstract -- The Imnaha and Grande Ronde River spring Chinook hatchery programs are components of the Lower Snake River Compensation Plan (LSRCP), funded through the U.S. Fish and Wildlife Service (USFWS), developed to mitigate for wild fish production lost as a result of construction of the four lower Snake River dams. Hatchery Chinook and steelhead smolts in the Snake River basin are produced at LSRCP hatcheries in Washington, Idaho and Oregon. Subsequent adult returns are meant to provide tribal and recreational (sport) fisheries and, in some cases, enhance natural spawner numbers. The Oregon Department of Fish and Wildlife (ODFW) initiated the Imnaha and Grande Ronde spring Chinook hatchery program in 1982 under the LSRCP. Subsequent program management has been coordinated between ODFW, the Confederated Tribes of the Umatilla Indian Reservation (CTUIR), and the Nez Perce Tribe (NPT). The Imnaha and Grande Ronde River hatchery programs are comprised of five components, each with smolt acclimation and adult collection facilities located on the Imnaha River, upper Grande Ronde River, Lookingglass and Catherine Creeks, and the Lostine River. The Lostine River program interacts with natural production within the broader Wallowa-Lostine population unit. Other hatchery program components are discrete to specific populations indicated. The Lookingglass Creek portion of the program focuses on reintroduction of spring Chinook to that stream and targets the release of 250,000 smolts. Each of the four remaining program components integrates natural-origin fish returning to each respective tributary into production. Smolt release goals, developed to meet LSRCP mitigation responsibilities; include 490,000 for the Imnaha, 250,000 for the Lostine and upper Grande Ronde rivers, and 150,000 for Catherine Creek. Fisheries that target returns to the Imnaha and Grande Ronde hatchery programs are guided by Fishery Management and Evaluation Plans (FMEP), approved by NOAA fisheries under limit 4 of the final 4(d) rule of the Endangered Species Act (ODFW 2011, ODFW and WDFW 2012). The objective of the FMEP is to provide recreational fishing opportunities and related benefits derived from harvest of Imnaha and Grande Ronde basin hatchery-origin spring Chinook salmon in Oregon and Washington in a manner that supports the continued survival and future recovery of natural-origin Chinook salmon. Each respective FMEP utilizes a management framework for harvest of adipose-clipped, hatchery-origin Snake River spring/summer Chinook salmon using abundance-based sliding scales to set annual fishery impacts. Fisheries are prescribed maximum impact rates for both direct and incidental mortality of natural-origin adult salmon in sport and tribal fisheries. Impacts are assessed for each population in relation to critical and minimum abundance thresholds (MAT) as described by the Interior Columbia Technical Recovery Team (ICTRT 2007). Population designations for the Imnaha and Grande Ronde Basins are listed in Table 1, and are based upon an analysis of Chinook salmon life history traits, distribution, abundance, and productivity, and geographical and ecological characteristics of the landscape within the Snake River Spring/Summer Chinook Salmon ESU (McElhany et al. 2000). The abundance-based harvest rate schedule for Imnaha and Grande Ronde Basin fisheries to be shared by all fishing entities in the basin is described in Table 2. Harvest is not considered when hatchery run size does not exceed the number of adults identified for broodstock and supplementation needs as described by sliding scale management plans set for each population’s hatchery program. Surplus is generally defined as the adult hatchery run projection less hatchery adults needed for broodstock. This approach limits sport harvest during years when wild fish runs are below MAT and hatchery fish runs are of similar size. In addition, near the lower end of the harvest rate scale, fisheries are not implemented until the allowable hatchery fish harvest exceeds 20 fish due to potential to over harvest within a single week. Fishery impacts to listed Snake River spring/summer Chinook salmon are assessed on a collective basis (i.e., the sum of recreational and tribal fisheries) by NOAA fisheries. However, the coordination of impact amongst states and tribes is a key component of executing conservation-based fisheries in the Imnaha and Grande Ronde Basins. Co-managers within each basin have developed, and implement annually, an impact sharing agreement that is described in Table 3. Within each fishery scenario, this agreement provides tribal fisheries more of the natural-origin impacts to reflect the non-selective nature of traditional fishing techniques. Recreational fisheries are provided a larger portion of the hatchery harvest such that all available impacts (hatchery and natural collectively) are shared equally (Table 3). Recreational fisheries administered by the states limit harvest (retention) of spring/summer Chinook hatchery-origin salmon with a clipped adipose fin (as evidenced by a healed scar). All salmon with an intact adipose fin (natural-origin) must be released back to the water. Therefore, incidental mortality impacts occur from catch and release of unclipped Snake River spring/summer Chinook salmon in fisheries targeting adipose-clipped hatchery Chinook salmon, and/or from the illegal retention of unclipped fish. It is generally assumed throughout the Columbia River Basin that the mortality rate resulting from the catch and release of salmon in fisheries is 10%. However, for Lookingglass Creek comanagers, with concurrence from NOAA fisheries, assume a slightly lower rate of 7.5% (ODFW and WDFW 2012). As stated in the FMEP, fisheries are adjusted or terminated when the total ESA take limit identified in Table 2 and 3 has been reached. Therefore, once fisheries are initiated regular monitoring is required to ensure consistency with co-manager agreements and FMEP requirements. The objective of this LSRCP project was to conduct statistical creel surveys to determine spring Chinook and steelhead ESA impact levels, harvest and release rates, and to inform decisions regarding fishery status in the Imnaha and Grande Ronde Basins in 2015. In this report, we describe creel surveys conducted and estimates of angler effort, catch, and harvest. In addition we compare these estimates in relation to estimates of natural and hatchery-origin returns to each population to assess consistency with prescribed impacts under FMEP guidelines. Lower Snake River Compensation Plan (LSRCP) ODFW Title: Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Harvest Monitoring - 2015 Annual Progress Report Abstract -- The Imnaha and Grande Ronde River spring Chinook hatchery programs are components of the Lower Snake River Compensation Plan (LSRCP), funded through the U.S. Fish and Wildlife Service (USFWS), developed to mitigate for wild fish production lost as a result of construction of the four lower Snake River dams. Hatchery Chinook and steelhead smolts in the Snake River basin are produced at LSRCP hatcheries in Washington, Idaho and Oregon. Subsequent adult returns are meant to provide tribal and recreational (sport) fisheries and, in some cases, enhance natural spawner numbers. The Oregon Department of Fish and Wildlife (ODFW) initiated the Imnaha and Grande Ronde spring Chinook hatchery program in 1982 under the LSRCP. Subsequent program management has been coordinated between ODFW, the Confederated Tribes of the Umatilla Indian Reservation (CTUIR), and the Nez Perce Tribe (NPT). The Imnaha and Grande Ronde River hatchery programs are comprised of five components, each with smolt acclimation and adult collection facilities located on the Imnaha River, upper Grande Ronde River, Lookingglass and Catherine Creeks, and the Lostine River. The Lostine River program interacts with natural production within the broader Wallowa-Lostine population unit. Other hatchery program components are discrete to specific populations indicated. The Lookingglass Creek portion of the program focuses on reintroduction of spring Chinook to that stream and targets the release of 250,000 smolts. Each of the four remaining program components integrates natural-origin fish returning to each respective tributary into production. Smolt release goals, developed to meet LSRCP mitigation responsibilities; include 490,000 for the Imnaha, 250,000 for the Lostine and upper Grande Ronde rivers, and 150,000 for Catherine Creek. Fisheries that target returns to the Imnaha and Grande Ronde hatchery programs are guided by Fishery Management and Evaluation Plans (FMEP), approved by NOAA fisheries under limit 4 of the final 4(d) rule of the Endangered Species Act (ODFW 2011, ODFW and WDFW 2012). The objective of the FMEP is to provide recreational fishing opportunities and related benefits derived from harvest of Imnaha and Grande Ronde basin hatchery-origin spring Chinook salmon in Oregon and Washington in a manner that supports the continued survival and future recovery of natural-origin Chinook salmon. Each respective FMEP utilizes a management framework for harvest of adipose-clipped, hatchery-origin Snake River spring/summer Chinook salmon using abundance-based sliding scales to set annual fishery impacts. Fisheries are prescribed maximum impact rates for both direct and incidental mortality of natural-origin adult salmon in sport and tribal fisheries. Impacts are assessed for each population in relation to critical and minimum abundance thresholds (MAT) as described by the Interior Columbia Technical Recovery Team (ICTRT 2007). Population designations for the Imnaha and Grande Ronde Basins are listed in Table 1, and are based upon an analysis of Chinook salmon life history traits, distribution, abundance, and productivity, and geographical and ecological characteristics of the landscape within the Snake River Spring/Summer Chinook Salmon ESU (McElhany et al. 2000). The abundance-based harvest rate schedule for Imnaha and Grande Ronde Basin fisheries to be shared by all fishing entities in the basin is described in Table 2. Harvest is not considered when hatchery run size does not exceed the number of adults identified for broodstock and supplementation needs as described by sliding scale management plans set for each population’s hatchery program. Surplus is generally defined as the adult hatchery run projection less hatchery adults needed for broodstock. This approach limits sport harvest during years when wild fish runs are below MAT and hatchery fish runs are of similar size. In addition, near the lower end of the harvest rate scale, fisheries are not implemented until the allowable hatchery fish harvest exceeds 20 fish due to potential to over harvest within a single week. Fishery impacts to listed Snake River spring/summer Chinook salmon are assessed on a collective basis (i.e., the sum of recreational and tribal fisheries) by NOAA fisheries. However, the coordination of impact amongst states and tribes is a key component of executing conservation-based fisheries in the Imnaha and Grande Ronde Basins. Co-managers within each basin have developed, and implement annually, an impact sharing agreement that is described in Table 3. Within each fishery scenario, this agreement provides tribal fisheries more of the natural-origin impacts to reflect the non-selective nature of traditional fishing techniques. Recreational fisheries are provided a larger portion of the hatchery harvest such that all available impacts (hatchery and natural collectively) are shared equally (Table 3). Recreational fisheries administered by the states limit harvest (retention) of spring/summer Chinook hatchery-origin salmon with a clipped adipose fin (as evidenced by a healed scar). All salmon with an intact adipose fin (natural-origin) must be released back to the water. Therefore, incidental mortality impacts occur from catch and release of unclipped Snake River spring/summer Chinook salmon in fisheries targeting adipose-clipped hatchery Chinook salmon, and/or from the illegal retention of unclipped fish. It is generally assumed throughout the Columbia River Basin that the mortality rate resulting from the catch and release of salmon in fisheries is 10%. However, for Lookingglass Creek comanagers, with concurrence from NOAA fisheries, assume a slightly lower rate of 7.5% (ODFW and WDFW 2012). As stated in the FMEP, fisheries are adjusted or terminated when the total ESA take limit identified in Table 2 and 3 has been reached. Therefore, once fisheries are initiated regular monitoring is required to ensure consistency with co-manager agreements and FMEP requirements. The objective of this LSRCP project was to conduct statistical creel surveys to determine spring Chinook and steelhead ESA impact levels, harvest and release rates, and to inform decisions regarding fishery status in the Imnaha and Grande Ronde Basins in 2015. In this report, we describe creel surveys conducted and estimates of angler effort, catch, and harvest. In addition we compare these estimates in relation to estimates of natural and hatchery-origin returns to each population to assess consistency with prescribed impacts under FMEP guidelines. Lower Snake River Compensation Plan (LSRCP) ODFW Close

• 13138. [Article] Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Harvest Monitoring - 2014 Annual Progress Report

  Abstract -- The Imnaha and Grande Ronde River spring Chinook hatchery programs are components of the Lower Snake River Compensation Plan (LSRCP), funded through the U.S. Fish and Wildlife Service (USFWS), ...

  Citation × Citation Citation Abstract Copy Title: Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Harvest Monitoring - 2014 Annual Progress Report Abstract -- The Imnaha and Grande Ronde River spring Chinook hatchery programs are components of the Lower Snake River Compensation Plan (LSRCP), funded through the U.S. Fish and Wildlife Service (USFWS), developed to mitigate for wild fish production lost as a result of construction of the four lower Snake River dams. Hatchery Chinook and steelhead smolts in the Snake River basin are produced at LSRCP hatcheries in Washington, Idaho and Oregon. Subsequent adult returns are meant to provide tribal and recreational (sport) fisheries and, in some cases, enhance natural spawner numbers. The Oregon Department of Fish and Wildlife initiated the Imnaha and Grande Ronde spring Chinook hatchery program in 1982 under the LSRCP. Subsequent program management has been coordinated between ODFW, Confederated Tribes of the Umatilla Indian Reservation (CTUIR), and Nez Perce Tribe (NPT). The Imnaha and Grande Ronde River hatchery programs are comprised of five components, each with smolt acclimation and adult collection facilities located on the Imnaha River, upper Grande Ronde River, Lookingglass and Catherine Creeks, and the Lostine River. The Lostine River program interacts with natural production within the broader Wallowa-Lostine population unit. Other hatchery program components are discrete to specific populations indicated. The Lookingglass Creek portion of the program focuses on reintroduction of spring Chinook to that stream and targets the release of 250,000 smolts originating from the Catherine Creek population. Each of the four remaining program components integrates natural-origin fish returning to each respective tributary into production. Smolt release goals, developed to meet LSRCP mitigation responsibilities, include 490,000 for the Imnaha, 250,000 for the Lostine and upper Grande Ronde rivers, and 150,000 for Catherine Creek. Fisheries that target returns to the Imnaha and Grande Ronde hatchery programs are guided by Fishery Management and Evaluation Plans (FMEP), approved by NOAA fisheries under limit 4 of the final 4(d) rule of the Endangered Species Act (ODFW 2011, ODFW and WDFW 2012). The objective of the FMEP is to provide recreational fishing opportunities and related benefits derived from harvest of Imnaha and Grande Ronde basin hatchery-origin spring Chinook salmon in Oregon and Washington in a manner that supports the continued survival and future recovery of natural-origin Chinook salmon. Each respective FMEP utilizes a management framework for harvest of adipose-clipped, hatchery-origin Snake River spring/summer Chinook salmon using abundance-based sliding scales to set annual fishery impacts. Fisheries are prescribed maximum impact rates for both direct and incidental mortality of natural-origin adult salmon in sport and tribal fisheries. Impacts are assessed for each population in relation to critical and minimum abundance thresholds (MAT) as described by the Interior Columbia Technical Recovery Team (ICTRT 2007). Population designations for the Imnaha and Grande Ronde Basins are listed in Table 1, and are based upon an analysis of Chinook salmon life history traits, distribution, abundance, and productivity, and geographical and ecological characteristics of the landscape within the Snake River Spring/Summer Chinook Salmon ESU (McElhany et al. 2000). The abundance-based harvest rate schedule for Imnaha and Grande Ronde Basin fisheries to be shared by all fishing entities in the basin is described in Table 2. Harvest is not considered when hatchery run size does not exceed the number of adults identified for broodstock and supplementation needs as described by sliding scale management plans set for each population’s hatchery program. Surplus is generally defined as the adult hatchery run projection less hatchery adults needed for broodstock. This approach limits sport harvest during years when wild fish runs are below MAT and hatchery fish runs are of similar size. In addition, near the lower end of the harvest rate scale, fisheries are not implemented until the allowable hatchery fish harvest exceeds 20 fish due to potential to over harvest within a single week. Fishery impacts to listed Snake River spring/summer Chinook salmon are assessed on a collective basis (i.e., the sum of recreational and tribal fisheries) by NOAA fisheries. However, the coordination of impact amongst states and tribes is a key component of executing conservation-based fisheries in the Imnaha and Grande Ronde Basins. Co-managers within each basin have developed, and implement annually, an impact sharing agreement that is described in Table 3. Within each fishery scenario, this agreement provides tribal fisheries more of the natural-origin impacts to reflect the non-selective nature of traditional fishing techniques. Recreational fisheries are provided a larger portion of the hatchery harvest such that all available impacts (hatchery and natural collectively) are shared equally (Table 3). Recreational fisheries administered by the states limit harvest (retention) of spring/summer Chinook hatchery-origin salmon with a clipped adipose fin (as evidenced by a healed scar). All salmon with an intact adipose fin (natural-origin) must be released back to the water. Therefore, incidental mortality impacts occur from catch and release of unclipped Snake River spring/summer Chinook salmon in fisheries targeting adipose-clipped hatchery Chinook salmon, and/or from the illegal retention of unclipped fish. It is generally assumed throughout the Columbia River Basin that the mortality rate resulting from the catch and release of salmon in fisheries is 10%. However, for Lookingglass Creek comanagers, with concurrence from NOAA fisheries, assume a slightly lower rate of 7.5% (ODFW and WDFW 2012). As stated in the FMEP, fisheries are adjusted or terminated when the total ESA take limit identified in Table 2 and 3 has been reached. Therefore, once fisheries are initiated regular monitoring is required to ensure consistency with co-manager agreements and FMEP requirements. The objective of this LSRCP project was to conduct statistical creel surveys to determine spring Chinook and steelhead ESA impact levels, harvest and release rates, and to inform decisions regarding fishery status in the Imnaha and Grande Ronde Basins in 2014. In this report, we describe creel surveys conducted and estimates of angler effort, catch, and harvest. In addition we compare these estimates in relation to estimates of natural and hatchery-origin returns to each population to assess consistency with prescribed impacts under FMEP guidelines. Lower Snake River Compensation Plan (LSRCP) ODFW Title: Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Harvest Monitoring - 2014 Annual Progress Report Abstract -- The Imnaha and Grande Ronde River spring Chinook hatchery programs are components of the Lower Snake River Compensation Plan (LSRCP), funded through the U.S. Fish and Wildlife Service (USFWS), developed to mitigate for wild fish production lost as a result of construction of the four lower Snake River dams. Hatchery Chinook and steelhead smolts in the Snake River basin are produced at LSRCP hatcheries in Washington, Idaho and Oregon. Subsequent adult returns are meant to provide tribal and recreational (sport) fisheries and, in some cases, enhance natural spawner numbers. The Oregon Department of Fish and Wildlife initiated the Imnaha and Grande Ronde spring Chinook hatchery program in 1982 under the LSRCP. Subsequent program management has been coordinated between ODFW, Confederated Tribes of the Umatilla Indian Reservation (CTUIR), and Nez Perce Tribe (NPT). The Imnaha and Grande Ronde River hatchery programs are comprised of five components, each with smolt acclimation and adult collection facilities located on the Imnaha River, upper Grande Ronde River, Lookingglass and Catherine Creeks, and the Lostine River. The Lostine River program interacts with natural production within the broader Wallowa-Lostine population unit. Other hatchery program components are discrete to specific populations indicated. The Lookingglass Creek portion of the program focuses on reintroduction of spring Chinook to that stream and targets the release of 250,000 smolts originating from the Catherine Creek population. Each of the four remaining program components integrates natural-origin fish returning to each respective tributary into production. Smolt release goals, developed to meet LSRCP mitigation responsibilities, include 490,000 for the Imnaha, 250,000 for the Lostine and upper Grande Ronde rivers, and 150,000 for Catherine Creek. Fisheries that target returns to the Imnaha and Grande Ronde hatchery programs are guided by Fishery Management and Evaluation Plans (FMEP), approved by NOAA fisheries under limit 4 of the final 4(d) rule of the Endangered Species Act (ODFW 2011, ODFW and WDFW 2012). The objective of the FMEP is to provide recreational fishing opportunities and related benefits derived from harvest of Imnaha and Grande Ronde basin hatchery-origin spring Chinook salmon in Oregon and Washington in a manner that supports the continued survival and future recovery of natural-origin Chinook salmon. Each respective FMEP utilizes a management framework for harvest of adipose-clipped, hatchery-origin Snake River spring/summer Chinook salmon using abundance-based sliding scales to set annual fishery impacts. Fisheries are prescribed maximum impact rates for both direct and incidental mortality of natural-origin adult salmon in sport and tribal fisheries. Impacts are assessed for each population in relation to critical and minimum abundance thresholds (MAT) as described by the Interior Columbia Technical Recovery Team (ICTRT 2007). Population designations for the Imnaha and Grande Ronde Basins are listed in Table 1, and are based upon an analysis of Chinook salmon life history traits, distribution, abundance, and productivity, and geographical and ecological characteristics of the landscape within the Snake River Spring/Summer Chinook Salmon ESU (McElhany et al. 2000). The abundance-based harvest rate schedule for Imnaha and Grande Ronde Basin fisheries to be shared by all fishing entities in the basin is described in Table 2. Harvest is not considered when hatchery run size does not exceed the number of adults identified for broodstock and supplementation needs as described by sliding scale management plans set for each population’s hatchery program. Surplus is generally defined as the adult hatchery run projection less hatchery adults needed for broodstock. This approach limits sport harvest during years when wild fish runs are below MAT and hatchery fish runs are of similar size. In addition, near the lower end of the harvest rate scale, fisheries are not implemented until the allowable hatchery fish harvest exceeds 20 fish due to potential to over harvest within a single week. Fishery impacts to listed Snake River spring/summer Chinook salmon are assessed on a collective basis (i.e., the sum of recreational and tribal fisheries) by NOAA fisheries. However, the coordination of impact amongst states and tribes is a key component of executing conservation-based fisheries in the Imnaha and Grande Ronde Basins. Co-managers within each basin have developed, and implement annually, an impact sharing agreement that is described in Table 3. Within each fishery scenario, this agreement provides tribal fisheries more of the natural-origin impacts to reflect the non-selective nature of traditional fishing techniques. Recreational fisheries are provided a larger portion of the hatchery harvest such that all available impacts (hatchery and natural collectively) are shared equally (Table 3). Recreational fisheries administered by the states limit harvest (retention) of spring/summer Chinook hatchery-origin salmon with a clipped adipose fin (as evidenced by a healed scar). All salmon with an intact adipose fin (natural-origin) must be released back to the water. Therefore, incidental mortality impacts occur from catch and release of unclipped Snake River spring/summer Chinook salmon in fisheries targeting adipose-clipped hatchery Chinook salmon, and/or from the illegal retention of unclipped fish. It is generally assumed throughout the Columbia River Basin that the mortality rate resulting from the catch and release of salmon in fisheries is 10%. However, for Lookingglass Creek comanagers, with concurrence from NOAA fisheries, assume a slightly lower rate of 7.5% (ODFW and WDFW 2012). As stated in the FMEP, fisheries are adjusted or terminated when the total ESA take limit identified in Table 2 and 3 has been reached. Therefore, once fisheries are initiated regular monitoring is required to ensure consistency with co-manager agreements and FMEP requirements. The objective of this LSRCP project was to conduct statistical creel surveys to determine spring Chinook and steelhead ESA impact levels, harvest and release rates, and to inform decisions regarding fishery status in the Imnaha and Grande Ronde Basins in 2014. In this report, we describe creel surveys conducted and estimates of angler effort, catch, and harvest. In addition we compare these estimates in relation to estimates of natural and hatchery-origin returns to each population to assess consistency with prescribed impacts under FMEP guidelines. Lower Snake River Compensation Plan (LSRCP) ODFW Close

• 13139. [Article] Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Harvest Monitoring - 2013 Annual Progress Report

  Abstract -- The Imnaha and Grande Ronde River spring Chinook hatchery programs are components of the Lower Snake River Compensation Plan (LSRCP), funded through the U.S. Fish and Wildlife Service (USFWS), ...

  Citation × Citation Citation Abstract Copy Title: Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Harvest Monitoring - 2013 Annual Progress Report Abstract -- The Imnaha and Grande Ronde River spring Chinook hatchery programs are components of the Lower Snake River Compensation Plan (LSRCP), funded through the U.S. Fish and Wildlife Service (USFWS), developed to mitigate for wild fish production lost as a result of construction of four lower Snake River dams. Hatchery Chinook and steelhead smolts in the Snake River basin are produced at LSRCP hatcheries in Washington, Idaho and Oregon. Subsequent adult returns are meant to provide tribal and recreational (sport) fisheries and, in some cases, enhance natural spawner numbers. The Oregon Department of Fish and Wildlife initiated the Imnaha and Grande Ronde spring Chinook hatchery program in 1982 under the LSRCP. Subsequent program management has been coordinated between ODFW, Confederated Tribes of the Umatilla Indian Reservation (CTUIR) and Nez Perce Tribe (NPT). The Imnaha and Grande Ronde River hatchery programs are comprised of five components, each with smolt acclimation and adult collection facilities located on the Imnaha River, upper Grande Ronde River, Lookingglass and Catherine Creeks, and the Lostine River. The Lostine River program interacts with natural production within the broader Wallowa-Lostine population unit. Other hatchery program components are discrete to specific populations indicated. The Lookingglass Creek portion of the program focuses on reintroduction of spring Chinook to that stream and targets the release of 250,000 smolts originating from the Catherine Creek population. Each of the four remaining program components integrates natural-origin fish returning to each respective tributary into production. Smolt release goals, developed to meet LSRCP mitigation responsibilities, include 490,000 for the Imnaha, 250,000 for the Lostine and upper Grande Ronde rivers, and 150,000 for Catherine Creek. Fisheries that target returns to the Imnaha and Grande Ronde hatchery programs are guided by Fishery Management and Evaluation Plans (FMEP), approved by NOAA fisheries under limit 4 of the final 4(d) rule of the Endangered Species Act (ODFW 2011, ODFW and WDFW 2012). The objective of the FMEP is to provide recreational fishing opportunities and related benefits derived from harvest of Imnaha and Grande Ronde basin hatchery-origin spring Chinook salmon in Oregon and Washington in a manner that supports the continued survival and future recovery of natural-origin Chinook salmon. Each respective FMEP utilizes a management framework for harvest of adipose-clipped, hatchery-origin Snake River spring/summer Chinook salmon using abundance-based sliding scales to set annual fishery impacts. Fisheries are prescribed maximum impact rates for both direct and incidental mortality of natural-origin adult salmon in sport and tribal fisheries. Impacts are assessed for each population in relation to critical and minimum abundance thresholds (MAT) as described by the Interior Columbia Technical Recovery Team (ICTRT 2007). Population designations for the Imnaha and Grande Ronde Basins are listed in Table 1, and are based upon an analysis of Chinook salmon life history traits, distribution, abundance, and productivity, and geographical and ecological characteristics of the landscape within the Snake River Spring/Summer Chinook Salmon ESU (McElhany et al. 2000). The abundance-based harvest rate schedule for Imnaha and Grande Ronde Basin fisheries to be shared by all fishing entities in the basin is described in Table 2. Harvest is not considered when hatchery run size does not exceed the number of adults identified for broodstock and supplementation needs as described by sliding scale management plans set for each population’s hatchery program. Surplus is generally defined as adult hatchery run projection less hatchery adults needed for broodstock. This approach limits sport harvest during years when wild fish runs are below MAT and hatchery fish runs are of similar size. In addition, near the lower end of the harvest rate scale, fisheries are not implemented until allowable hatchery fish harvest exceeds 20 fish due to potential to over harvest within a single week. Fishery impacts to listed Snake River spring/summer Chinook salmon are assessed on a collective basis (i.e., the sum of recreational and tribal fisheries) by NOAA fisheries. However, the coordination of impact amongst states and tribes is a key component of executing conservation-based fisheries in the Imnaha and Grande Ronde Basins. Co-managers within each basin have developed, and implement annually, an impact sharing agreement that is described in Table 3. Within each fishery scenario, this agreement provides tribal fisheries more of the natural-origin impacts to reflect the non-selective nature of traditional fishing techniques. Recreational fisheries are provided more of the hatchery harvest such that all available impacts (hatchery and natural collectively) are shared equally (Table 3). Recreational fisheries administered by the states limit harvest (retention) of spring/summer Chinook hatchery-origin salmon with a clipped adipose fin (as evidenced by a healed scar). All salmon with an intact adipose fin (natural-origin) must be released back to the water. Therefore, incidental mortality impacts occur from catch and release of unclipped Snake River spring/summer Chinook salmon in fisheries targeting adipose-clipped hatchery Chinook salmon, and/or from the illegal retention of unclipped fish. It is generally assumed throughout the Columbia River Basin that the mortality rate resulting from the catch and release of salmon in fisheries is 10%. However, for Lookingglass Creek comanagers, with concurrence from NOAA fisheries, assume a slightly lower rate of 7.5% (ODFW and WDFW 2012). As stated in the FMEP, fisheries are adjusted or terminated when the total ESA take limit identified in Table 2 and 3 has been reached. Therefore, once fisheries are initiated regular monitoring is required to ensure consistency with co-manager agreements and FMEP requirements. The objective of this LSRCP project was to conduct statistical creel surveys determine spring Chinook and steelhead ESA impact levels, harvest and release rates, and to inform decisions regarding fishery status in the Imnaha and Grande Ronde Basins in 2013. In this report, we describe creel surveys conducted and estimates of angler effort, catch, and harvest. In addition we compare these estimates in relation to post-season preliminary estimates of natural and hatchery-origin returns to each population to assess consistency with prescribed impacts under FMEP guidelines. Lower Snake River Compensation Plan (LSRCP) ODFW Title: Lower Snake River Compensation Plan; Oregon Spring Chinook Salmon Harvest Monitoring - 2013 Annual Progress Report Abstract -- The Imnaha and Grande Ronde River spring Chinook hatchery programs are components of the Lower Snake River Compensation Plan (LSRCP), funded through the U.S. Fish and Wildlife Service (USFWS), developed to mitigate for wild fish production lost as a result of construction of four lower Snake River dams. Hatchery Chinook and steelhead smolts in the Snake River basin are produced at LSRCP hatcheries in Washington, Idaho and Oregon. Subsequent adult returns are meant to provide tribal and recreational (sport) fisheries and, in some cases, enhance natural spawner numbers. The Oregon Department of Fish and Wildlife initiated the Imnaha and Grande Ronde spring Chinook hatchery program in 1982 under the LSRCP. Subsequent program management has been coordinated between ODFW, Confederated Tribes of the Umatilla Indian Reservation (CTUIR) and Nez Perce Tribe (NPT). The Imnaha and Grande Ronde River hatchery programs are comprised of five components, each with smolt acclimation and adult collection facilities located on the Imnaha River, upper Grande Ronde River, Lookingglass and Catherine Creeks, and the Lostine River. The Lostine River program interacts with natural production within the broader Wallowa-Lostine population unit. Other hatchery program components are discrete to specific populations indicated. The Lookingglass Creek portion of the program focuses on reintroduction of spring Chinook to that stream and targets the release of 250,000 smolts originating from the Catherine Creek population. Each of the four remaining program components integrates natural-origin fish returning to each respective tributary into production. Smolt release goals, developed to meet LSRCP mitigation responsibilities, include 490,000 for the Imnaha, 250,000 for the Lostine and upper Grande Ronde rivers, and 150,000 for Catherine Creek. Fisheries that target returns to the Imnaha and Grande Ronde hatchery programs are guided by Fishery Management and Evaluation Plans (FMEP), approved by NOAA fisheries under limit 4 of the final 4(d) rule of the Endangered Species Act (ODFW 2011, ODFW and WDFW 2012). The objective of the FMEP is to provide recreational fishing opportunities and related benefits derived from harvest of Imnaha and Grande Ronde basin hatchery-origin spring Chinook salmon in Oregon and Washington in a manner that supports the continued survival and future recovery of natural-origin Chinook salmon. Each respective FMEP utilizes a management framework for harvest of adipose-clipped, hatchery-origin Snake River spring/summer Chinook salmon using abundance-based sliding scales to set annual fishery impacts. Fisheries are prescribed maximum impact rates for both direct and incidental mortality of natural-origin adult salmon in sport and tribal fisheries. Impacts are assessed for each population in relation to critical and minimum abundance thresholds (MAT) as described by the Interior Columbia Technical Recovery Team (ICTRT 2007). Population designations for the Imnaha and Grande Ronde Basins are listed in Table 1, and are based upon an analysis of Chinook salmon life history traits, distribution, abundance, and productivity, and geographical and ecological characteristics of the landscape within the Snake River Spring/Summer Chinook Salmon ESU (McElhany et al. 2000). The abundance-based harvest rate schedule for Imnaha and Grande Ronde Basin fisheries to be shared by all fishing entities in the basin is described in Table 2. Harvest is not considered when hatchery run size does not exceed the number of adults identified for broodstock and supplementation needs as described by sliding scale management plans set for each population’s hatchery program. Surplus is generally defined as adult hatchery run projection less hatchery adults needed for broodstock. This approach limits sport harvest during years when wild fish runs are below MAT and hatchery fish runs are of similar size. In addition, near the lower end of the harvest rate scale, fisheries are not implemented until allowable hatchery fish harvest exceeds 20 fish due to potential to over harvest within a single week. Fishery impacts to listed Snake River spring/summer Chinook salmon are assessed on a collective basis (i.e., the sum of recreational and tribal fisheries) by NOAA fisheries. However, the coordination of impact amongst states and tribes is a key component of executing conservation-based fisheries in the Imnaha and Grande Ronde Basins. Co-managers within each basin have developed, and implement annually, an impact sharing agreement that is described in Table 3. Within each fishery scenario, this agreement provides tribal fisheries more of the natural-origin impacts to reflect the non-selective nature of traditional fishing techniques. Recreational fisheries are provided more of the hatchery harvest such that all available impacts (hatchery and natural collectively) are shared equally (Table 3). Recreational fisheries administered by the states limit harvest (retention) of spring/summer Chinook hatchery-origin salmon with a clipped adipose fin (as evidenced by a healed scar). All salmon with an intact adipose fin (natural-origin) must be released back to the water. Therefore, incidental mortality impacts occur from catch and release of unclipped Snake River spring/summer Chinook salmon in fisheries targeting adipose-clipped hatchery Chinook salmon, and/or from the illegal retention of unclipped fish. It is generally assumed throughout the Columbia River Basin that the mortality rate resulting from the catch and release of salmon in fisheries is 10%. However, for Lookingglass Creek comanagers, with concurrence from NOAA fisheries, assume a slightly lower rate of 7.5% (ODFW and WDFW 2012). As stated in the FMEP, fisheries are adjusted or terminated when the total ESA take limit identified in Table 2 and 3 has been reached. Therefore, once fisheries are initiated regular monitoring is required to ensure consistency with co-manager agreements and FMEP requirements. The objective of this LSRCP project was to conduct statistical creel surveys determine spring Chinook and steelhead ESA impact levels, harvest and release rates, and to inform decisions regarding fishery status in the Imnaha and Grande Ronde Basins in 2013. In this report, we describe creel surveys conducted and estimates of angler effort, catch, and harvest. In addition we compare these estimates in relation to post-season preliminary estimates of natural and hatchery-origin returns to each population to assess consistency with prescribed impacts under FMEP guidelines. Lower Snake River Compensation Plan (LSRCP) ODFW Close

• 13140. [Article] Status and Distribution of Native Fishes in the Goose Lake Basin Information Reports number 2008-02

  Abstract -- This study describes the current distribution of the nine native fish species in the Oregon portion of the Goose Lake basin (Lake County): Goose Lake redband trout Oncorhynchus mykiss ssp., ...

  Citation × Citation Citation Abstract Copy Title: Status and Distribution of Native Fishes in the Goose Lake Basin Information Reports number 2008-02 Abstract -- This study describes the current distribution of the nine native fish species in the Oregon portion of the Goose Lake basin (Lake County): Goose Lake redband trout Oncorhynchus mykiss ssp., Goose Lake lamprey Entosphenus sp., Goose Lake tui chub Siphateles bicolor thalassinus, Goose Lake sucker Catostomus occidentalis lacusanserinus, Modoc sucker Catostomus microps, Pit-Klamath brook lamprey Entosphenus lethophagus, speckled dace Rhinichthys osculus, Pit roach Lavinia symmetricus mitrulus, and Pit sculpin Cottus pitensis. The Goose Lake basin is an endorheic, or topographically closed basin located in south central Oregon and northeastern California. The basin is within the usually closed northeastern extremity of the adjoining Sacramento River basin, astride the Oregon-California boundary. Although most of the lake lies in California, most of its valley and nearly two-thirds of the total drainage area (~722 sq. mi.) are in Oregon. The largest streams in the basin are Drews, Cottonwood, and Thomas Creeks. Annual precipitation averages about 36 cm per year (Phillips and van Denburgh 1971). Goose Lake overflowed briefly into the North Fork Pit River in 1868 and 1881, but storage and diversion of irrigation water has substantially reduced the inflow and future overflow is unlikely (USGS 1971). The lakebed was dry in the summers of 1926, 1929- 1934, and 1992. About half the basin is forestland, 20% is hay fields and pastureland, and 16% is shrub and rangeland. Currently, almost 35% of the inflow is diverted for irrigation (OWRD 1989). The Goose Lake basin is home to four endemic fish taxa: the Goose Lake redband trout, lamprey, sucker, and tui chub. Endemic fishes of the Goose Lake basin split their life histories between Goose Lake and its tributaries, as opposed to the five native but non-endemic species that primarily occupy stream habitats. Pit roach and all endemic fishes except Goose Lake tui chub are listed as a “species of concern” by the USFWS, a designation that implies there is concern about species viability, but not enough information is known to initiate a listing review for threatened or endangered status. The Modoc sucker was listed as a federally endangered species in 1985 (USFWS 1985). No formal recovery plan was required due to an existing “Action Plan for the Recovery of the Modoc Sucker” (USFWS 1984). Most of the recovery actions outlined in the action plan were either completed or are no longer relevant (Stewart Reid, Western Fishes, personal communication). However, actions 26 and 27 pertaining to range expansion remain incomplete. Action 26 suggests reclassification to threatened upon establishment of safe populations (for 3-5 years) throughout the Rush and Turner Creek watersheds in the Pit River basin. Action 27 suggests delisting upon establishing safe populations in two other historic streams. At the time of listing, the historic range of Modoc sucker was thought to have included only two small tributaries of the Pit River in Modoc and Lassen Counties, Ash and Turner Creeks (USFWS 1985). Therefore, a major recovery goal was to expand the species’ range with additional populations (USFWS 1984). In 2001, reexamination of historical documents and museum specimens established that Modoc suckers had also historically occupied Thomas Creek in the Goose Lake basin. Field collections in 2001, with subsequent morphological and genetic analysis, confirmed that the population was still present in Thomas Creek (Stewart Reid, Western Fishes, personal communication); however, the broader range of Modoc sucker in the Goose Lake watershed was not known. In 1995, the Goose Lake Fishes Working Group drafted a conservation plan for “prelisting” recovery of all native fish in response to severe drought and habitat degradation (GLFWG 1995). The Aquatic Inventories Project of the Oregon Department of Fish and Wildlife (ODFW) conducted habitat and fish distribution surveys (1991-1995) to obtain baseline information to help inform recovery efforts (ODFW, unpublished data). Since then, field work to monitor the distribution and abundance of Goose Lake fishes has been limited and sporadic, targeting only Goose Lake redband trout and Modoc sucker (Dambacher 2001; Reid 2007). No comprehensive follow up work has been conducted to evaluate fish response to climatic conditions, habitat restoration projects, and continued irrigation activities. ODFW recently drafted a status review of native fish of Oregon (ODFW 2005). Except for redband trout, Goose Lake fishes were not included in the status review due to a lack of new information since the previous status review in 1995 (Kostow et al. 1995). Further, the review of Goose Lake redband trout was limited by a lack of long-term data series. The first objective of this study was to document the current distribution of native fishes in Oregon’s portion of the Goose Lake basin and assess changes in distribution that may have occurred since the last surveys were conducted 12 years ago. The second objective was to provide new information about the distribution of Modoc suckers within the basin. The third objective was to determine relative abundance and age-class diversity of native fishes at randomly selected sample sites. All objectives were addressed throughout the potential riverine distribution of fish in the Oregon portion of the Goose Lake basin. Information gathered in this study is critical to effective conservation and management of each species and its habitat. In addition, this report describes the distribution and relative abundance of nonnative fishes (fathead minnow (Pimephales promelas), brown bullhead (Ameiurus nebulosus), white crappie (Pomoxis annularis), yellow perch (Perca flavescens), pumpkinseed (Lepomis gibbosus), and brook trout (Salvelinus fontinalis)) in the basin. Unlike prior efforts, this study used a statisticallybased design to select sample points with the aim of achieving a representative sample across the Oregon portion of the Goose Lake watershed. Additionally, a wide array of fish sampling gear was employed to maximize our ability to capture all fish species present across the diversity of habitat types encountered. Title: Status and Distribution of Native Fishes in the Goose Lake Basin Information Reports number 2008-02 Abstract -- This study describes the current distribution of the nine native fish species in the Oregon portion of the Goose Lake basin (Lake County): Goose Lake redband trout Oncorhynchus mykiss ssp., Goose Lake lamprey Entosphenus sp., Goose Lake tui chub Siphateles bicolor thalassinus, Goose Lake sucker Catostomus occidentalis lacusanserinus, Modoc sucker Catostomus microps, Pit-Klamath brook lamprey Entosphenus lethophagus, speckled dace Rhinichthys osculus, Pit roach Lavinia symmetricus mitrulus, and Pit sculpin Cottus pitensis. The Goose Lake basin is an endorheic, or topographically closed basin located in south central Oregon and northeastern California. The basin is within the usually closed northeastern extremity of the adjoining Sacramento River basin, astride the Oregon-California boundary. Although most of the lake lies in California, most of its valley and nearly two-thirds of the total drainage area (~722 sq. mi.) are in Oregon. The largest streams in the basin are Drews, Cottonwood, and Thomas Creeks. Annual precipitation averages about 36 cm per year (Phillips and van Denburgh 1971). Goose Lake overflowed briefly into the North Fork Pit River in 1868 and 1881, but storage and diversion of irrigation water has substantially reduced the inflow and future overflow is unlikely (USGS 1971). The lakebed was dry in the summers of 1926, 1929- 1934, and 1992. About half the basin is forestland, 20% is hay fields and pastureland, and 16% is shrub and rangeland. Currently, almost 35% of the inflow is diverted for irrigation (OWRD 1989). The Goose Lake basin is home to four endemic fish taxa: the Goose Lake redband trout, lamprey, sucker, and tui chub. Endemic fishes of the Goose Lake basin split their life histories between Goose Lake and its tributaries, as opposed to the five native but non-endemic species that primarily occupy stream habitats. Pit roach and all endemic fishes except Goose Lake tui chub are listed as a “species of concern” by the USFWS, a designation that implies there is concern about species viability, but not enough information is known to initiate a listing review for threatened or endangered status. The Modoc sucker was listed as a federally endangered species in 1985 (USFWS 1985). No formal recovery plan was required due to an existing “Action Plan for the Recovery of the Modoc Sucker” (USFWS 1984). Most of the recovery actions outlined in the action plan were either completed or are no longer relevant (Stewart Reid, Western Fishes, personal communication). However, actions 26 and 27 pertaining to range expansion remain incomplete. Action 26 suggests reclassification to threatened upon establishment of safe populations (for 3-5 years) throughout the Rush and Turner Creek watersheds in the Pit River basin. Action 27 suggests delisting upon establishing safe populations in two other historic streams. At the time of listing, the historic range of Modoc sucker was thought to have included only two small tributaries of the Pit River in Modoc and Lassen Counties, Ash and Turner Creeks (USFWS 1985). Therefore, a major recovery goal was to expand the species’ range with additional populations (USFWS 1984). In 2001, reexamination of historical documents and museum specimens established that Modoc suckers had also historically occupied Thomas Creek in the Goose Lake basin. Field collections in 2001, with subsequent morphological and genetic analysis, confirmed that the population was still present in Thomas Creek (Stewart Reid, Western Fishes, personal communication); however, the broader range of Modoc sucker in the Goose Lake watershed was not known. In 1995, the Goose Lake Fishes Working Group drafted a conservation plan for “prelisting” recovery of all native fish in response to severe drought and habitat degradation (GLFWG 1995). The Aquatic Inventories Project of the Oregon Department of Fish and Wildlife (ODFW) conducted habitat and fish distribution surveys (1991-1995) to obtain baseline information to help inform recovery efforts (ODFW, unpublished data). Since then, field work to monitor the distribution and abundance of Goose Lake fishes has been limited and sporadic, targeting only Goose Lake redband trout and Modoc sucker (Dambacher 2001; Reid 2007). No comprehensive follow up work has been conducted to evaluate fish response to climatic conditions, habitat restoration projects, and continued irrigation activities. ODFW recently drafted a status review of native fish of Oregon (ODFW 2005). Except for redband trout, Goose Lake fishes were not included in the status review due to a lack of new information since the previous status review in 1995 (Kostow et al. 1995). Further, the review of Goose Lake redband trout was limited by a lack of long-term data series. The first objective of this study was to document the current distribution of native fishes in Oregon’s portion of the Goose Lake basin and assess changes in distribution that may have occurred since the last surveys were conducted 12 years ago. The second objective was to provide new information about the distribution of Modoc suckers within the basin. The third objective was to determine relative abundance and age-class diversity of native fishes at randomly selected sample sites. All objectives were addressed throughout the potential riverine distribution of fish in the Oregon portion of the Goose Lake basin. Information gathered in this study is critical to effective conservation and management of each species and its habitat. In addition, this report describes the distribution and relative abundance of nonnative fishes (fathead minnow (Pimephales promelas), brown bullhead (Ameiurus nebulosus), white crappie (Pomoxis annularis), yellow perch (Perca flavescens), pumpkinseed (Lepomis gibbosus), and brook trout (Salvelinus fontinalis)) in the basin. Unlike prior efforts, this study used a statisticallybased design to select sample points with the aim of achieving a representative sample across the Oregon portion of the Goose Lake watershed. Additionally, a wide array of fish sampling gear was employed to maximize our ability to capture all fish species present across the diversity of habitat types encountered. Close

• 13141. [Article] Evaluating Coastal Protection Services Associated with Restoration Management of an Endangered Shorebird in Oregon, U.S.A.

  Coastal sand dunes and beaches offer a variety of ecosystem services such as coastal protection, sand stabilization, species conservation, and recreation. However, the management and balance of ecosystem ...

  Citation × Citation Citation Abstract Copy Title: Evaluating Coastal Protection Services Associated with Restoration Management of an Endangered Shorebird in Oregon, U.S.A. Author: Carroll, Lindsay J. Coastal sand dunes and beaches offer a variety of ecosystem services such as coastal protection, sand stabilization, species conservation, and recreation. However, the management and balance of ecosystem services offered by dunes and beaches is challenging when ecosystem services interact across the landscape. Management focusing only on one ecosystem service may result in unintended consequences and trade-offs between other key services. Understanding the magnitude of the trade-offs and linkages between services provides a more holistic approach for reducing unintended consequences and maximizing function. The degradation of habitats and land use changes associated with expanding human populations has resulted in the need for species conservation. However, species conservation techniques can sometimes have unintended consequences for other services. Given the mandate of the Endangered Species Act to restore habitat structure and function essential to endangered or threatened species, it becomes critical to evaluate the implications of species conservation management initiatives to reduce negative implications to other key services. The coastal dune systems of the Pacific Northwest (PNW) are a prime example of how ecosystem services, such as species conservation and coastal protection, can interact with one another. Over the last 125 years in the Pacific Northwest (PNW), the intentional introduction of two non-native congeneric beach grasses (Ammophila arenaria and A. breviligulata) has increased coastal protection through the creation of foredunes, but also dramatically altered the dune ecosystem. Both invasive grasses build taller dunes that range from 3 - 18 m in height compared to the native grass, Elymus mollis. Increased foredune elevations generate greater coastal protection services that are increasingly important given sea level rise and extreme storm events on the PNW coast. However, the beach grasses have dramatically changed the beach/dune community, resulting in the decline of several native dune plants and animals. One species that is negatively affected by the grass invasion is the Western snowy plover (Charadrius nivosus nivosus), an endemic shorebird living on beaches and dunes in the Pacific Northwest. This shorebird was listed threatened under the Endangered Species Act in 1993 and a recovery plan was established that employed multiple recovery techniques. The most important part of the plan involves establishing habitat restoration areas (HRAs) where dunes are bulldozed, reducing dune elevations, burying the grass, and returning the dunes to an open shifting sand environment, historically preferred by the plover. Recent coastal hazards modeling revealed that the changes in beach and dune shape associated with plover restoration increases coastal exposure to flooding and erosion at certain locations along the Oregon coast, particularly under projected climate change scenarios of sea level rise and extreme storms. As part of future plover management, four critical habitat areas were proposed for Tillamook County, Oregon: Nehalem River Spit, Bayocean Spit, Netarts Spit, and Sand Lake South. Given the interest in plover habitat restoration in Tillamook County, this research project addresses the following questions: (1) What is the present day dune geomorphology and exposure to coastal hazards at four proposed critical habitat (PCH) areas in Tillamook County, Oregon; and (2) how do changes in beach geomorphology associated with different restoration scenarios alter coastal exposure today, under projected sea level rise and storm scenarios? To address the coastal geomorphological impacts of HRA installation on the four proposed areas, multiple restoration scenarios that reduce foredune elevation were evaluated under present day sea level and potential future sea level rise and extreme storminess scenarios, using coastal exposure modeling techniques. The model projections provide site-specific information on the exposure of HRAs to overtopping under different restoration conditions. We determined that exposure to flooding was dependent on proposed HRA site and restoration scenario, and was exacerbated by sea level rise and extreme storms. Empirical models projected the greatest flooding exposure would occur at Nehalem River Spit, followed by Netarts Spit, and then Bayocean Spit and Sand Lake South, which did not differ. Exposure to flooding at present day dunes was low across all sites, but with increasing exposure to flooding as foredune elevations were reduced to 6.0 m or below, as could happen with plover habitat restoration. Under present day water levels, restoring foredune elevations to 6.0 m or below would likely result in roughly 5 days of overtopping per year at Nehalem River Spit, Bayocean Spit, and Netarts Spit, and 4 days of overtopping at Sand Lake South. Flooding under various foredune restoration scenarios increased under higher sea level rise scenarios. Flooding exposure for the 6.0 m restoration scenario exceeded 10 days per year at Nehalem River Spit and 5 days per year at Bayocean Spit, Netarts Spit, and Sand Lake South. Overall exposure to flooding under the extreme storm scenarios was dependent on proposed HRA site, restoration scenario, and increased wave conditions, such as wave height, period, and water level. Similar to the empirical model, flooding exposure under extreme storm scenarios increased when foredune elevations were reduced to 6.0 m or below, across all sites. The site with the greatest overall flooding exposure during extreme storms was Bayocean Spit. Flooding distance was dependent on restoration scenario and site while flooding duration was only dependent on restoration scenario. The 5.5 m restoration scenario under higher storm water levels resulted in one hour or more of flooding exposure at least one day per year at Nehalem River Spit, Netarts Spit, and Bayocean Spit. The overall likelihood of overwash extending to 150 m or more into the dune field during extreme storms was at least 5 days when selecting to reduce foredune to restoration elevations of 7.0 m or below across all sites. The effect of higher wave heights and greater wave periods was more important to overtopping distance than restoration scenario. Learning from current plover management, combined with the coastal exposure analysis we conducted here, could enable managers to develop site-specific restoration plans that maximize plover recovery while minimizing coastal exposure. This research will give resource managers information on the coastal exposure associated with proposed HRAs and the foredune reduction scenarios they might want to employ at the different sites. It will allow them to identify the best restoration scenarios to maximum habitat restoration without compromising coastal protection, and thus balance some important services of dunes and beaches. Regardless of management objective, identifying the unintended consequences of restoration to key ecosystem services is necessary for the holistic management of our dynamic coasts, especially with projected sea level rise and the uncertainty of frequent and extreme storms. Title: Evaluating Coastal Protection Services Associated with Restoration Management of an Endangered Shorebird in Oregon, U.S.A. Author: Carroll, Lindsay J. Coastal sand dunes and beaches offer a variety of ecosystem services such as coastal protection, sand stabilization, species conservation, and recreation. However, the management and balance of ecosystem services offered by dunes and beaches is challenging when ecosystem services interact across the landscape. Management focusing only on one ecosystem service may result in unintended consequences and trade-offs between other key services. Understanding the magnitude of the trade-offs and linkages between services provides a more holistic approach for reducing unintended consequences and maximizing function. The degradation of habitats and land use changes associated with expanding human populations has resulted in the need for species conservation. However, species conservation techniques can sometimes have unintended consequences for other services. Given the mandate of the Endangered Species Act to restore habitat structure and function essential to endangered or threatened species, it becomes critical to evaluate the implications of species conservation management initiatives to reduce negative implications to other key services. The coastal dune systems of the Pacific Northwest (PNW) are a prime example of how ecosystem services, such as species conservation and coastal protection, can interact with one another. Over the last 125 years in the Pacific Northwest (PNW), the intentional introduction of two non-native congeneric beach grasses (Ammophila arenaria and A. breviligulata) has increased coastal protection through the creation of foredunes, but also dramatically altered the dune ecosystem. Both invasive grasses build taller dunes that range from 3 - 18 m in height compared to the native grass, Elymus mollis. Increased foredune elevations generate greater coastal protection services that are increasingly important given sea level rise and extreme storm events on the PNW coast. However, the beach grasses have dramatically changed the beach/dune community, resulting in the decline of several native dune plants and animals. One species that is negatively affected by the grass invasion is the Western snowy plover (Charadrius nivosus nivosus), an endemic shorebird living on beaches and dunes in the Pacific Northwest. This shorebird was listed threatened under the Endangered Species Act in 1993 and a recovery plan was established that employed multiple recovery techniques. The most important part of the plan involves establishing habitat restoration areas (HRAs) where dunes are bulldozed, reducing dune elevations, burying the grass, and returning the dunes to an open shifting sand environment, historically preferred by the plover. Recent coastal hazards modeling revealed that the changes in beach and dune shape associated with plover restoration increases coastal exposure to flooding and erosion at certain locations along the Oregon coast, particularly under projected climate change scenarios of sea level rise and extreme storms. As part of future plover management, four critical habitat areas were proposed for Tillamook County, Oregon: Nehalem River Spit, Bayocean Spit, Netarts Spit, and Sand Lake South. Given the interest in plover habitat restoration in Tillamook County, this research project addresses the following questions: (1) What is the present day dune geomorphology and exposure to coastal hazards at four proposed critical habitat (PCH) areas in Tillamook County, Oregon; and (2) how do changes in beach geomorphology associated with different restoration scenarios alter coastal exposure today, under projected sea level rise and storm scenarios? To address the coastal geomorphological impacts of HRA installation on the four proposed areas, multiple restoration scenarios that reduce foredune elevation were evaluated under present day sea level and potential future sea level rise and extreme storminess scenarios, using coastal exposure modeling techniques. The model projections provide site-specific information on the exposure of HRAs to overtopping under different restoration conditions. We determined that exposure to flooding was dependent on proposed HRA site and restoration scenario, and was exacerbated by sea level rise and extreme storms. Empirical models projected the greatest flooding exposure would occur at Nehalem River Spit, followed by Netarts Spit, and then Bayocean Spit and Sand Lake South, which did not differ. Exposure to flooding at present day dunes was low across all sites, but with increasing exposure to flooding as foredune elevations were reduced to 6.0 m or below, as could happen with plover habitat restoration. Under present day water levels, restoring foredune elevations to 6.0 m or below would likely result in roughly 5 days of overtopping per year at Nehalem River Spit, Bayocean Spit, and Netarts Spit, and 4 days of overtopping at Sand Lake South. Flooding under various foredune restoration scenarios increased under higher sea level rise scenarios. Flooding exposure for the 6.0 m restoration scenario exceeded 10 days per year at Nehalem River Spit and 5 days per year at Bayocean Spit, Netarts Spit, and Sand Lake South. Overall exposure to flooding under the extreme storm scenarios was dependent on proposed HRA site, restoration scenario, and increased wave conditions, such as wave height, period, and water level. Similar to the empirical model, flooding exposure under extreme storm scenarios increased when foredune elevations were reduced to 6.0 m or below, across all sites. The site with the greatest overall flooding exposure during extreme storms was Bayocean Spit. Flooding distance was dependent on restoration scenario and site while flooding duration was only dependent on restoration scenario. The 5.5 m restoration scenario under higher storm water levels resulted in one hour or more of flooding exposure at least one day per year at Nehalem River Spit, Netarts Spit, and Bayocean Spit. The overall likelihood of overwash extending to 150 m or more into the dune field during extreme storms was at least 5 days when selecting to reduce foredune to restoration elevations of 7.0 m or below across all sites. The effect of higher wave heights and greater wave periods was more important to overtopping distance than restoration scenario. Learning from current plover management, combined with the coastal exposure analysis we conducted here, could enable managers to develop site-specific restoration plans that maximize plover recovery while minimizing coastal exposure. This research will give resource managers information on the coastal exposure associated with proposed HRAs and the foredune reduction scenarios they might want to employ at the different sites. It will allow them to identify the best restoration scenarios to maximum habitat restoration without compromising coastal protection, and thus balance some important services of dunes and beaches. Regardless of management objective, identifying the unintended consequences of restoration to key ecosystem services is necessary for the holistic management of our dynamic coasts, especially with projected sea level rise and the uncertainty of frequent and extreme storms. Close

• 13142. [Article] The influence of climate change and restoration on stream temperature

  Water temperature is an essential property of a stream. Temperature regulates physical and biochemical processes in aquatic habitats. Various factors related to climatic conditions, landscape characteristics, ...

  Citation × Citation Citation Abstract Copy Title: The influence of climate change and restoration on stream temperature Author: Diabat, Mousa Water temperature is an essential property of a stream. Temperature regulates physical and biochemical processes in aquatic habitats. Various factors related to climatic conditions, landscape characteristics, and channel structure directly influence stream temperature. Numerous studies indicate that increased average air temperature during the past century has led to stream warming across the world. The trend of stream warming was also present in spring-fed watersheds, where summer flow has decreased. In addition, anthropogenic practices that alter the natural landscape and channel structure, such as forest management, agriculture, and mining contributed to stream warming. For example, deforested and unshaded stream reaches or dredged channels were warmer than shaded reaches and meandering streams. Stream temperatures in North American lotic habitats are of a specific concern due to their significant economic, cultural, and ecological value. With climate projections indicating that air temperature will only continue to rise throughout the 21st century, cold- or cool-water organisms, especially fishes, will be affected. Therefore, there is a strong need to better understand the impacts of changing climate, riparian landscape, and channel structure on a stream's heat budget. This may assist in restoring the historic thermal regime in impacted sites and mitigating the impacts of future climate change. This study looks into the relative influences of the different factors on a stream's heat budget with three manuscripts: one on stream temperature response to diel timing of air warming, one on stream temperature response to changes in air temperature, flow, and riparian vegetation, and one on stream temperature response to air warming and channel reconstruction. I used the software Heat Source version 8.05 to simulate stream temperature for all three analyses along the Middle Fork John Day River, Oregon USA. Two of the manuscripts were applied to an upper 37 km section of the Middle Fork John Day River (presented in chapter 2 and 3), where the third manuscript was applied to a 1.5-km section. The sensitivity analysis of stream temperature response to diel timing of air warming (Chapter 2: Diel Timing of Warmer Air under Climate Change Affects Magnitude, Timing, and Duration of Stream Temperature Change) was based on scenarios representing uniform air warming over the diel period, daytime warming, and nighttime warming. Uniform warming of air temperature is a simple representation of increases in the average daily or monthly temperatures generated by the 'delta method'. The delta method relies on adding a constant value to the air temperature time-series data. This constant value is the difference (delta) between base case average air temperatures and the projected one. Scenarios of daytime or nighttime warming represent conditions under which most of the warming of the air occurs during the daytime or the nighttime, respectively. I simulated the stream temperature response to warmer air conditions of +2 °C and +4 °C in daily average for all three cases of air warming conditions. The three cases of different diel distributions of air warming generated 7-day average daily maximum stream temperature (7DADM) increases of approximately +1.8 °C ± 0.1 °C at the downstream end of the study section relative to the base case. In most parts of the reach, the three distributions of air warming generated different ranges of stream temperatures, different 7DADM values, different durations of stream temperature changes, and different average daily temperatures. Changes of stream temperature were out of phase with imposed changes of air temperature. Therefore, nighttime warming of air temperatures would cause the greatest increase in maximum daily stream temperature, which typically occurs during the daytime. The sensitivity analysis of the relative influences of changes in air temperature, stream flow, and riparian vegetation on stream temperature (Chapter 3: Assessing Stream Temperature Response to Cumulative Influence of Changing Air Temperature, Flow, and Riparian Vegetation). This study summarized stream temperature simulation in 36 scenarios representing possible manifestations of 21st century climate conditions and land management strategies. In addition to existing conditions (base case) of flow, air temperature, and riparian vegetation, scenarios consisted of: two air temperature increases of 2 °C and 4 °C, two stream flow variations of +30% and -30%, three spatially uniform riparian vegetation conditions that create averages of effective shade 7%, 34%, and 79%, in addition to 14% for base case conditions. Results suggest that variation in riparian vegetation was the dominant factor influencing stream temperature because it regulates incoming shortwave radiation, the largest heat input to the stream, while variation in stream flow has a negligible influence. Results indicated that increasing the effective shade along the study section, particularly in the currently unshaded sections, could mitigate the influence of increasing air temperature, and would reduce stream temperature maxima below current values even under future climate conditions of warmer air. With the small influence it had, increasing stream flow reduced the 7DADM under low shade conditions. However, increasing stream flow showed counterintuitive results as it contributed to increasing stream temperature maxima when the stream was heavily shaded. The applied study examined the stream temperature response to restoration practices and their potential to mitigate the influence of warmer air conditions (Chapter 4: Estimating Stream Temperature Response to Restoring Channel and Riparian Vegetation and the Potential to Mitigate Warmer Air Conditions). This study focused on a 1.5 km section along the upper part of the Middle Fork John Day River that was modified due to past anthropogenic activities of mining for gold and timber harvest. Currently, the riparian vegetation of the study site is mostly shrubs and stands of short trees. Restoration designs call for the restoration of both the channel structure and replanting the riparian vegetation. Simulation results showed that the 7DADM was higher in the restored channel than the existing channel with both conditions of low and high effective shade conditions. However, a combined restoration practice of channel reconstruction and medium effective shade conditions reduced stream temperature maxima more than restoring riparian vegetation alone. In addition, results showed that restoring riparian vegetation was sufficient to mitigate the influence of warmer air on stream temperature, while restoring the channel alone is not. Heat budget analysis showed that heat accumulation during the daytime increased in the restored channel, which was longer, narrower, and deeper than the existing channel. It is important to emphasize that stream temperature is one of many goals that restoration activities aim to improve. Furthermore, differences in 7DADM among the different scenarios of restoration are negligible. Such small differences could hardly be measure. While this study examined a short section of 1.5 km, longer stream sections may increase the differences in 7DADM. Primary conclusions of this study are: 1) daily maxima of stream temperature will increase in response to increased air temperature regardless of the distribution of air warming during the diel cycle; 2) nighttime air warming caused a greater increase in stream temperature maximum than daytime warming; 3) riparian vegetation was the dominant factor on stream's heat budget, more than air temperature or stream flow; 4) restoring riparian vegetation mitigated the influence of warmer air; 5) restoring channel structure alone was not sufficient to lower temperature maxima; and 6) restoration project was most successful in improving degraded stream temperature when combined with channel reconstruction and improved riparian shade. Title: The influence of climate change and restoration on stream temperature Author: Diabat, Mousa Water temperature is an essential property of a stream. Temperature regulates physical and biochemical processes in aquatic habitats. Various factors related to climatic conditions, landscape characteristics, and channel structure directly influence stream temperature. Numerous studies indicate that increased average air temperature during the past century has led to stream warming across the world. The trend of stream warming was also present in spring-fed watersheds, where summer flow has decreased. In addition, anthropogenic practices that alter the natural landscape and channel structure, such as forest management, agriculture, and mining contributed to stream warming. For example, deforested and unshaded stream reaches or dredged channels were warmer than shaded reaches and meandering streams. Stream temperatures in North American lotic habitats are of a specific concern due to their significant economic, cultural, and ecological value. With climate projections indicating that air temperature will only continue to rise throughout the 21st century, cold- or cool-water organisms, especially fishes, will be affected. Therefore, there is a strong need to better understand the impacts of changing climate, riparian landscape, and channel structure on a stream's heat budget. This may assist in restoring the historic thermal regime in impacted sites and mitigating the impacts of future climate change. This study looks into the relative influences of the different factors on a stream's heat budget with three manuscripts: one on stream temperature response to diel timing of air warming, one on stream temperature response to changes in air temperature, flow, and riparian vegetation, and one on stream temperature response to air warming and channel reconstruction. I used the software Heat Source version 8.05 to simulate stream temperature for all three analyses along the Middle Fork John Day River, Oregon USA. Two of the manuscripts were applied to an upper 37 km section of the Middle Fork John Day River (presented in chapter 2 and 3), where the third manuscript was applied to a 1.5-km section. The sensitivity analysis of stream temperature response to diel timing of air warming (Chapter 2: Diel Timing of Warmer Air under Climate Change Affects Magnitude, Timing, and Duration of Stream Temperature Change) was based on scenarios representing uniform air warming over the diel period, daytime warming, and nighttime warming. Uniform warming of air temperature is a simple representation of increases in the average daily or monthly temperatures generated by the 'delta method'. The delta method relies on adding a constant value to the air temperature time-series data. This constant value is the difference (delta) between base case average air temperatures and the projected one. Scenarios of daytime or nighttime warming represent conditions under which most of the warming of the air occurs during the daytime or the nighttime, respectively. I simulated the stream temperature response to warmer air conditions of +2 °C and +4 °C in daily average for all three cases of air warming conditions. The three cases of different diel distributions of air warming generated 7-day average daily maximum stream temperature (7DADM) increases of approximately +1.8 °C ± 0.1 °C at the downstream end of the study section relative to the base case. In most parts of the reach, the three distributions of air warming generated different ranges of stream temperatures, different 7DADM values, different durations of stream temperature changes, and different average daily temperatures. Changes of stream temperature were out of phase with imposed changes of air temperature. Therefore, nighttime warming of air temperatures would cause the greatest increase in maximum daily stream temperature, which typically occurs during the daytime. The sensitivity analysis of the relative influences of changes in air temperature, stream flow, and riparian vegetation on stream temperature (Chapter 3: Assessing Stream Temperature Response to Cumulative Influence of Changing Air Temperature, Flow, and Riparian Vegetation). This study summarized stream temperature simulation in 36 scenarios representing possible manifestations of 21st century climate conditions and land management strategies. In addition to existing conditions (base case) of flow, air temperature, and riparian vegetation, scenarios consisted of: two air temperature increases of 2 °C and 4 °C, two stream flow variations of +30% and -30%, three spatially uniform riparian vegetation conditions that create averages of effective shade 7%, 34%, and 79%, in addition to 14% for base case conditions. Results suggest that variation in riparian vegetation was the dominant factor influencing stream temperature because it regulates incoming shortwave radiation, the largest heat input to the stream, while variation in stream flow has a negligible influence. Results indicated that increasing the effective shade along the study section, particularly in the currently unshaded sections, could mitigate the influence of increasing air temperature, and would reduce stream temperature maxima below current values even under future climate conditions of warmer air. With the small influence it had, increasing stream flow reduced the 7DADM under low shade conditions. However, increasing stream flow showed counterintuitive results as it contributed to increasing stream temperature maxima when the stream was heavily shaded. The applied study examined the stream temperature response to restoration practices and their potential to mitigate the influence of warmer air conditions (Chapter 4: Estimating Stream Temperature Response to Restoring Channel and Riparian Vegetation and the Potential to Mitigate Warmer Air Conditions). This study focused on a 1.5 km section along the upper part of the Middle Fork John Day River that was modified due to past anthropogenic activities of mining for gold and timber harvest. Currently, the riparian vegetation of the study site is mostly shrubs and stands of short trees. Restoration designs call for the restoration of both the channel structure and replanting the riparian vegetation. Simulation results showed that the 7DADM was higher in the restored channel than the existing channel with both conditions of low and high effective shade conditions. However, a combined restoration practice of channel reconstruction and medium effective shade conditions reduced stream temperature maxima more than restoring riparian vegetation alone. In addition, results showed that restoring riparian vegetation was sufficient to mitigate the influence of warmer air on stream temperature, while restoring the channel alone is not. Heat budget analysis showed that heat accumulation during the daytime increased in the restored channel, which was longer, narrower, and deeper than the existing channel. It is important to emphasize that stream temperature is one of many goals that restoration activities aim to improve. Furthermore, differences in 7DADM among the different scenarios of restoration are negligible. Such small differences could hardly be measure. While this study examined a short section of 1.5 km, longer stream sections may increase the differences in 7DADM. Primary conclusions of this study are: 1) daily maxima of stream temperature will increase in response to increased air temperature regardless of the distribution of air warming during the diel cycle; 2) nighttime air warming caused a greater increase in stream temperature maximum than daytime warming; 3) riparian vegetation was the dominant factor on stream's heat budget, more than air temperature or stream flow; 4) restoring riparian vegetation mitigated the influence of warmer air; 5) restoring channel structure alone was not sufficient to lower temperature maxima; and 6) restoration project was most successful in improving degraded stream temperature when combined with channel reconstruction and improved riparian shade. Close

• 13143. [Article] Crustal architecture and magma dynamics in a large continental magmatic system : a case study of the Purico-Chascon Volcanic Complex, Northern Chile

  The ~1 Myr history of the Purico-Chascon volcanic complex (PCVC) records significant changes in the production and storage of magmas in the crust. At ~1 Ma activity at the PCVC initiated with the eruption ...

  Citation × Citation Citation Abstract Copy Title: Crustal architecture and magma dynamics in a large continental magmatic system : a case study of the Purico-Chascon Volcanic Complex, Northern Chile Author: Burns, Dale H. The ~1 Myr history of the Purico-Chascon volcanic complex (PCVC) records significant changes in the production and storage of magmas in the crust. At ~1 Ma activity at the PCVC initiated with the eruption of a large 80-100 km³ crystal-rich dacite ignimbrite with restricted whole rock ⁸⁷Sr/⁸⁶Sr isotope ratios between 0.7085-0.7090. In-situ analyses of plagioclase from the Purico ignimbrite have ⁸⁷Sr/⁸⁶Sr=0.7087-0.7090. The dacite magma accumulated and evolved at relatively low temperatures around 800-850 °C in the upper crust at 4-8 km depth. Minor andesite and rhyolite pumice late in the sequence have similar restricted whole rock ⁸⁷Sr/⁸⁶Sr=0.7089-0.7091. The radiogenic isotopes of this 0.98 Ma activity are consistent with all these compositions resulting from 50 to 70% crustal assimilation by parental Central Andean "baseline" magmas at depths between 15-30 km. The final eruptions at the PCVC occurred <0.18 Ma producing three small < 5 km³ crystal-rich dacite lava domes with whole rock ⁸⁷Sr/⁸⁶Sr ratios 0.7075 to 0.7081 containing abundant basaltic-andesite enclaves with whole rock ⁸⁷Sr/⁸⁶Sr ratios of 0.7057- 0.7061. Plagioclase and amphibole from samples from the largest of these domes, Cerro Chascon, record two distinct magmatic environments; an upper crustal environment identical to the Purico ignimbrite and a second deeper, ~15-20 km depth, higher temperature (~922-1001 °C) environment consistent with conditions recorded in the basaltic andesite enclaves. Accordingly, plagioclase cores in the host dacite lava and enclaves have enriched in-situ ⁸⁷Sr/⁸⁶Sr isotopic compositions of 0.7083 to 0.7095 while plagioclase rims and microphenocrysts in the enclaves have ⁸⁷Sr/⁸⁶Sr isotope ratios from 0.7057 to 0.7065 and 0.7062 to 0.7064 respectively. Lavas from Cerro Chascon also contain abundant Fo82 olivine with spinel and basaltic melt inclusions that crystallized in a deep crustal environment (>1250 °C) consistent with a lower crustal MASH zone. The high baseline isotopic ratios observed in bulk rock and plagioclase crystals from Cerro Chascon (0.7057-0.7065) are consistent with MASH processes. The evolution of the PCVC is a microcosm of the Andean arc in this region where, from 10 - 1 Ma, dominantly dacitic upper crustal magmatism of the Altiplano-Puna Volcanic Complex ignimbrite flare-up persisted until ~1 Ma, when smaller volume, more heterogeneous and less isotopically enriched basaltic andesite to dacite composite volcanoes signal a return to steady state arc volcanism. I suggest that the PCVC captures the transition of the Andean arc from flare-up to steady state. The temporal trend at the PCVC is consistent with a waning thermal flux. High magmatic fluxes during the flare-up would have resulted in elevated geothermal gradients and efficient crustal processing leading to a dominantly dacitic upper crust (0 to 35 km) that fed the large volume Purico ignimbrite. As magmatic flux and thermal energy wanes, crustal isotherms relax resulting in greater thermal contrast between parental magmas, crust and remnant upper crustal dacite magma. This manifests in more heterogeneity and the survival of less isotopically enriched magmas in the upper crust. These arc scale magma dynamics are recorded even at the intra-crystalline scale. Individual crystals from Cerro Chascon also record vital information on the crystallization and evolution of mantle-derived magmas in continental magmatic arcs. Fo₈₂ olivine, olivine hosted spinel, and basaltic melt inclusions record the crystallization of olivine at >1250 °C in conditions consistent with a lower crustal (~70 km depth) MASH zone. Another significant crystallization event appears to have occurred at ~20 km depth, characterized by the crystallization of high An plagioclase (An₇₂₋₈₄) at ~1100-1050 °C followed by high-Al amphibole (~12-15 wt.% Al₂O₃) at ~1000-950 °C. The appearance of amphibole on the liquidus appears to have resulted from a nearly 2-fold increase in melt water content following ~45% crystallization of high An plagioclase. Following this extensive crystallization the highly crystalline mafic magma ascended into the upper crust and interacted with the remnant crystal mush from the Purico ignimbrite magma reservoir. Low An plagioclase (An₃₉₋₅₅), low Al amphibole (~6-9 wt.% Al₂O₃), sanidine, and biotite retain the chemical composition of the Purico ignimbrite magma, whereas, olivine, high An plagioclase, and high Al amphibole record the mafic recharge magma. The textures and compositions observed in Cerro Chascon are common in both continental and oceanic magmatic arcs worldwide and I propose that multiple crystallization events and upper crustal assimilation are fundamental processes intrinsic to arc magmatism. I have also used in situ ⁸⁷Sr/⁸⁶Sr isotope ratios in plagioclase from andesite, dacite, and rhyolite pumice from the ~1 Ma Purico ignimbrite to determine the cause for compositional zoning in the Purico ignimbrite magma reservoir. Andesite pumice contains two texturally, compositionally, and isotopically distinct types of plagioclase, small (<500 μm) subhedral to euhedral crystals with high MgO (130-490 ppm) and low ⁸⁷Sr/⁸⁶r crystals (0.7076-0.7084) record a hot (>900 °C) andesite magma derived from an ~20 km deep magma reservoir. In contrast, the second type of plagioclase in the andesite appear to broken fragments of larger crystals and have significantly lower MgO (90-240 ppm), higher ⁸⁷Sr/⁸⁶Sr (0.7096-0.7114), and appears to be derived from the lower temperature (crystallized at ~800-900 °C), upper crustal (<10 km) plutonic basement. Dacite pumice also contains two texturally and compositionally distinct types of plagioclase. However, both types have very restricted MgO (b.d.l.-200 ppm) and ⁸⁷Sr/⁸⁶Sr (0.7085-0.7095) ratios and appear to have grown at ~850°C. These crystals are also significantly larger (>1000 μm) than plagioclase from the andesite pumice and have clear euhedral rims. Rhyolite pumice from the Purico ignimbrite also contains distinct types of plagioclase. Both types of plagioclase are similar in size (<500 μm) and appear to be fragments of larger crystals. One type is characterized by low MgO (b.d.l.-240 ppm) and restricted ⁸⁷Sr/⁸⁶Sr isotope ratios (0.7088-0.7095) similar to plagioclase in the dacite pumice, and the other has significantly higher ⁸⁷Sr/⁸⁶Sr ratios (0.7095-0.7103) consistent with the upper crustal ignimbrite basement. The compositional variations observed in plagioclase crystals from the Purico ignimbrites are consistent with the recharge of a previously emplaced upper crustal (4-8 km depth) dacite magma reservoir by a hotter, deeper (20 km deep) andesite. During ascent, the andesite incorporated crystals from the surrounding upper crustal plutonic bodies before pooling against the residence dacite magma and crystallizing. Crystallization of the andesite resulted in the expulsion of a rhyolite interstitial melt that ascended through the dacite reservoir and pooled at the top of the reservoir. The rhyolite melt incorporated crystals from the dacite magma during ascent as well as crystals from the roof rock, which in the case of the Purico ignimbrite represents the plutonic remnants from other large silicic magmatic systems associated with the APVC. Thus, the compositional variations observed in the Purico ignimbrite results from a combination of crustal assimilation, crystallization, and melt extraction all initiated by mafic recharge. Title: Crustal architecture and magma dynamics in a large continental magmatic system : a case study of the Purico-Chascon Volcanic Complex, Northern Chile Author: Burns, Dale H. The ~1 Myr history of the Purico-Chascon volcanic complex (PCVC) records significant changes in the production and storage of magmas in the crust. At ~1 Ma activity at the PCVC initiated with the eruption of a large 80-100 km³ crystal-rich dacite ignimbrite with restricted whole rock ⁸⁷Sr/⁸⁶Sr isotope ratios between 0.7085-0.7090. In-situ analyses of plagioclase from the Purico ignimbrite have ⁸⁷Sr/⁸⁶Sr=0.7087-0.7090. The dacite magma accumulated and evolved at relatively low temperatures around 800-850 °C in the upper crust at 4-8 km depth. Minor andesite and rhyolite pumice late in the sequence have similar restricted whole rock ⁸⁷Sr/⁸⁶Sr=0.7089-0.7091. The radiogenic isotopes of this 0.98 Ma activity are consistent with all these compositions resulting from 50 to 70% crustal assimilation by parental Central Andean "baseline" magmas at depths between 15-30 km. The final eruptions at the PCVC occurred <0.18 Ma producing three small < 5 km³ crystal-rich dacite lava domes with whole rock ⁸⁷Sr/⁸⁶Sr ratios 0.7075 to 0.7081 containing abundant basaltic-andesite enclaves with whole rock ⁸⁷Sr/⁸⁶Sr ratios of 0.7057- 0.7061. Plagioclase and amphibole from samples from the largest of these domes, Cerro Chascon, record two distinct magmatic environments; an upper crustal environment identical to the Purico ignimbrite and a second deeper, ~15-20 km depth, higher temperature (~922-1001 °C) environment consistent with conditions recorded in the basaltic andesite enclaves. Accordingly, plagioclase cores in the host dacite lava and enclaves have enriched in-situ ⁸⁷Sr/⁸⁶Sr isotopic compositions of 0.7083 to 0.7095 while plagioclase rims and microphenocrysts in the enclaves have ⁸⁷Sr/⁸⁶Sr isotope ratios from 0.7057 to 0.7065 and 0.7062 to 0.7064 respectively. Lavas from Cerro Chascon also contain abundant Fo82 olivine with spinel and basaltic melt inclusions that crystallized in a deep crustal environment (>1250 °C) consistent with a lower crustal MASH zone. The high baseline isotopic ratios observed in bulk rock and plagioclase crystals from Cerro Chascon (0.7057-0.7065) are consistent with MASH processes. The evolution of the PCVC is a microcosm of the Andean arc in this region where, from 10 - 1 Ma, dominantly dacitic upper crustal magmatism of the Altiplano-Puna Volcanic Complex ignimbrite flare-up persisted until ~1 Ma, when smaller volume, more heterogeneous and less isotopically enriched basaltic andesite to dacite composite volcanoes signal a return to steady state arc volcanism. I suggest that the PCVC captures the transition of the Andean arc from flare-up to steady state. The temporal trend at the PCVC is consistent with a waning thermal flux. High magmatic fluxes during the flare-up would have resulted in elevated geothermal gradients and efficient crustal processing leading to a dominantly dacitic upper crust (0 to 35 km) that fed the large volume Purico ignimbrite. As magmatic flux and thermal energy wanes, crustal isotherms relax resulting in greater thermal contrast between parental magmas, crust and remnant upper crustal dacite magma. This manifests in more heterogeneity and the survival of less isotopically enriched magmas in the upper crust. These arc scale magma dynamics are recorded even at the intra-crystalline scale. Individual crystals from Cerro Chascon also record vital information on the crystallization and evolution of mantle-derived magmas in continental magmatic arcs. Fo₈₂ olivine, olivine hosted spinel, and basaltic melt inclusions record the crystallization of olivine at >1250 °C in conditions consistent with a lower crustal (~70 km depth) MASH zone. Another significant crystallization event appears to have occurred at ~20 km depth, characterized by the crystallization of high An plagioclase (An₇₂₋₈₄) at ~1100-1050 °C followed by high-Al amphibole (~12-15 wt.% Al₂O₃) at ~1000-950 °C. The appearance of amphibole on the liquidus appears to have resulted from a nearly 2-fold increase in melt water content following ~45% crystallization of high An plagioclase. Following this extensive crystallization the highly crystalline mafic magma ascended into the upper crust and interacted with the remnant crystal mush from the Purico ignimbrite magma reservoir. Low An plagioclase (An₃₉₋₅₅), low Al amphibole (~6-9 wt.% Al₂O₃), sanidine, and biotite retain the chemical composition of the Purico ignimbrite magma, whereas, olivine, high An plagioclase, and high Al amphibole record the mafic recharge magma. The textures and compositions observed in Cerro Chascon are common in both continental and oceanic magmatic arcs worldwide and I propose that multiple crystallization events and upper crustal assimilation are fundamental processes intrinsic to arc magmatism. I have also used in situ ⁸⁷Sr/⁸⁶Sr isotope ratios in plagioclase from andesite, dacite, and rhyolite pumice from the ~1 Ma Purico ignimbrite to determine the cause for compositional zoning in the Purico ignimbrite magma reservoir. Andesite pumice contains two texturally, compositionally, and isotopically distinct types of plagioclase, small (<500 μm) subhedral to euhedral crystals with high MgO (130-490 ppm) and low ⁸⁷Sr/⁸⁶r crystals (0.7076-0.7084) record a hot (>900 °C) andesite magma derived from an ~20 km deep magma reservoir. In contrast, the second type of plagioclase in the andesite appear to broken fragments of larger crystals and have significantly lower MgO (90-240 ppm), higher ⁸⁷Sr/⁸⁶Sr (0.7096-0.7114), and appears to be derived from the lower temperature (crystallized at ~800-900 °C), upper crustal (<10 km) plutonic basement. Dacite pumice also contains two texturally and compositionally distinct types of plagioclase. However, both types have very restricted MgO (b.d.l.-200 ppm) and ⁸⁷Sr/⁸⁶Sr (0.7085-0.7095) ratios and appear to have grown at ~850°C. These crystals are also significantly larger (>1000 μm) than plagioclase from the andesite pumice and have clear euhedral rims. Rhyolite pumice from the Purico ignimbrite also contains distinct types of plagioclase. Both types of plagioclase are similar in size (<500 μm) and appear to be fragments of larger crystals. One type is characterized by low MgO (b.d.l.-240 ppm) and restricted ⁸⁷Sr/⁸⁶Sr isotope ratios (0.7088-0.7095) similar to plagioclase in the dacite pumice, and the other has significantly higher ⁸⁷Sr/⁸⁶Sr ratios (0.7095-0.7103) consistent with the upper crustal ignimbrite basement. The compositional variations observed in plagioclase crystals from the Purico ignimbrites are consistent with the recharge of a previously emplaced upper crustal (4-8 km depth) dacite magma reservoir by a hotter, deeper (20 km deep) andesite. During ascent, the andesite incorporated crystals from the surrounding upper crustal plutonic bodies before pooling against the residence dacite magma and crystallizing. Crystallization of the andesite resulted in the expulsion of a rhyolite interstitial melt that ascended through the dacite reservoir and pooled at the top of the reservoir. The rhyolite melt incorporated crystals from the dacite magma during ascent as well as crystals from the roof rock, which in the case of the Purico ignimbrite represents the plutonic remnants from other large silicic magmatic systems associated with the APVC. Thus, the compositional variations observed in the Purico ignimbrite results from a combination of crustal assimilation, crystallization, and melt extraction all initiated by mafic recharge. Close

• 13144. [Article] Stratigraphy and sedimentology of the middle eocene Cowlitz Formation and adjacent sedimentary and volcanic units in the Longview-Kelso area, southwest Washington

  Geologic mapping of the Longview-Kelso area and the measurement and description of a composite 650-meter thick stratigraphic section of the Cowlitz Formation (Tc) in Coal Creek using bio-, magneto-, litho-, ...

  Citation × Citation Citation Abstract Copy Title: Stratigraphy and sedimentology of the middle eocene Cowlitz Formation and adjacent sedimentary and volcanic units in the Longview-Kelso area, southwest Washington Author: McCutcheon, Mark S. Geologic mapping of the Longview-Kelso area and the measurement and description of a composite 650-meter thick stratigraphic section of the Cowlitz Formation (Tc) in Coal Creek using bio-, magneto-, litho-, and sequence stratigraphy reveals a complex interplay of Cowlitz micaceous, lithic arkosic shelf to tidal/estuarine to delta plain facies associations, and Grays River basalt lava flows and interbedded basalt volcaniclastics from nearby Grays River eruptive centers (e.g., Mt. Solo and Rocky Point). The lower 100 meters of the Coal Creek section (informal unit 1, Chron 18r) consists of micaceous, lithic arkosic sandstone and siltstone and minor coals, was deposited as part of a highstand system tract (HST) at the base of 3rd order cycle number 3. This unit consists of four dominantly tidal shoaling-upward arkosic sandstone parasequences reflecting upper shoreface to delta plain depositional environments. The overlying unit 2 (Chron 18n) is defined by abundant Grays River basalt volcaniclastic interbeds that intertongue with Cowlitz lithic arkoses. This unit represents the latter part of 3rd order cycle 3, and consists of mostly fining- and thinning-upward parasequences of middle shoreface to delta plain successions of an aggradational to transgressive parasequence set. Near the top of unit 2 is a maximum marine flooding surface depositing lower shoreface lithic arkosic sandstone to shelf siltstones over upper shoreface micaceous lithic arkose. Unit 3 comprises 3rd order cycle 4 (Chron 17r), a lowstand system tract, and consists of 6 mostly fining- and thinning-upward parasequences of lower shoreface to delta plain facies associations. A parasequence or erosional boundary at the base of unit 5 (Chron 17r) consists of submarine channel-fill scoured into underlying micaceous siltstones, produced during a lowstand system tract (LST) of 3rd order cycle 5. This deep marine channel-fill sequence is overlain by thinlybedded to laminated overbank distal turbidites and hemipelagic siltstones that define the top of the Coal Creek section. These 5 informal units in Coal Creek lithologically and chronologically correlate to 5 similar informal units defined by Payne (1998) in the type section of Cowlitz Formation in Olequa Creek near Vader -30 km to the north. Middle Eocene Grays River Volcanics of the study area are mapped as two separate units: a lower unit over 150 meters thick in places, consisting of subaerial basaltic flows and invasive flows (Tgvl), intrusions (Tgvis and Tgvid), and volcaniclastics (Tgvsl); and an upper unit consisting of commonly mollusk-bearing, shallow marine basaltic sedimentary interbeds that intertongue with the Cowlitz Formation (Tgvs2), particularly Cowlitz unit 2 of the Coal Creek section. These volcaniclastic deposits are intrabasinal, derived from volcanic highlands to the west and northwest, and local phreatomagmatic tuff cones. The lower Grays River volcaniclastic unit typically overlies Grays River flows in the study area and is divided into 5 informal facies. Geochemically, Grays River flows in the study area fall within normal parameters (3 to 4% TiO2 and high iron tholeiitic basalts). However, basalt flows and bedded scoriaceous breccias near Rocky Point are anomalously low in TiO2 and are considered in this study to be a separate volcanic subunit (Rocky Point Basalts), time equivalent to and interfingering with Grays River lavas, but may represent mixing with shallower western Cascade calc-alkaline magma. Over 60 younger Grays River dikes intrude the Cowlitz Formation in Coal Creek. A dike low in the Coal Creek section is dated at 40 ± 0.36 Ma, and an invasive flow at Mt. Solo is dated at 36.98 ±.78 Ma. Volcanics capping the hills east of the Cowlitz River are chemically distinct as slightly younger western Cascade basaltic andesite flows, and two dikes east of the river are chemically distinct as western Cascade andesite. Overlying Grays River Volcanics and Cowlitz Formation in much of the study area, are clayey and commonly tuffaceous siltstones and silty sandstones, possibly of the late Eocene-early Oligocene Toutle Formation, a new unit to this area. The Toutle Formation is a mixture of wave and stream reworked micaceous and arkosic Cowlitz Formation and fresh silicic pyroclastic ash and pumice from the active western Cascade arc. An angular unconformity separates the Paleogene Grays River Volcanics, Cowlitz Formation, and Toutle Formation from the early to middle Miocene Columbia River Basalt Group. Based on lithology, geochemistry, stratigraphic relationships, and magnetic polarity, 6 individual Columbia River Basalt flows have been mapped in this study. The three lower Grande Ronde flows are of normal polarity and Ortley low MgO chemical composition. The lowermost flow (N2 Ortley #1) is absent in the Columbia Heights area, low MgO, about 10 meters thick and consists of pillow-palagonite sequences in the upper quarry on Mt. Solo. Aphyric N2 Ortley flow #2 is over 35 meters thick with well-developed upper and lower colonnade, and of intermediate MgO. N2 Ortley flow #3 is pillow-palagonite in the Storedahl Quarry and low MgO. A -4-meter thick tuffaceous overbank siltstone and basalt conglomeratic channel interbed separates the three low MgO Ortley flows from the overlying high MgO N2 Grande Ronde Sentinel Bluffs flow. A single exposure of well-developed large colonnade with sparse 1 cm labradorite laths, and reddish oxidized soil, defines the N Sand Hollow flow of the Frenchman Springs Member of the Wanapum Formation. The overlying Pomona Member is mapped based on previous work by other authors. Pliocene gravels and arkosic sand of the Troutdale Formation form upland terrace deposits up to 100 meters thick in southern parts of the study area, and represent the uplifted paleo-thalweg and overbank flood deposits of the downcutting, antecedent ancestral Columbia River. Well-rounded clasts are a mixture of extrabasinal granitic and metamorphic quartzite, and intrabasinal porphyritic basaltic andesite, dacite, and basalt from the western Cascades and Columbia River Basalts. Troutdale terrace gravels grade northward into contemporaneous volcanic pebble and cobble gravel terrace deposits produced along the ancestral Cowlitz River that are dominantly composed of porphyritic andesite gravel and volcanic sand from the western Cascades. Lower terraces along the Cowlitz River were deposited by the late Pleistocene Missoula Floods. All of these unconsolidated to semiconsolidated gravels and sands are prone to landslides, and the Aldercrest-Banyon landslide, the second worst landslide disaster in American history, occurred in the Troutdale Formation gravels. After eruption of the Grays River Volcanics and deposition of the Cowlitz Formation, the forearc underwent a period of transtension in the late-middle Eocene related to magmatic upwelling and reorganization of the subducting Farallon Plate. This event produced a northwest-trending set of oblique slip normal faults, along which Grays River dikes intruded. Starting in the early Miocene the region underwent a transpressional event, reactivating many of the northwest-trending faults, and producing the Columbia Heights Anticline, Hazel Dell Syncline, the Coal Creek Fault, and the Kelso Fault Zone. The paleotopography resulting from this event was stream eroded to a nearly flat plain before emplacement of the Columbia River Basalts, which are nearly horizontal today. Continued offset along the northwest-trending fault set has also offset the Columbia River Basalts. Continued oblique slip post-Miocene broad arching of the Coast Range and downcutting by the Columbia and Cowlitz Rivers has resulted in Pliocene and Pleistocene terraces, and produced an east-west fault set that offsets all earlier structural features. Title: Stratigraphy and sedimentology of the middle eocene Cowlitz Formation and adjacent sedimentary and volcanic units in the Longview-Kelso area, southwest Washington Author: McCutcheon, Mark S. Geologic mapping of the Longview-Kelso area and the measurement and description of a composite 650-meter thick stratigraphic section of the Cowlitz Formation (Tc) in Coal Creek using bio-, magneto-, litho-, and sequence stratigraphy reveals a complex interplay of Cowlitz micaceous, lithic arkosic shelf to tidal/estuarine to delta plain facies associations, and Grays River basalt lava flows and interbedded basalt volcaniclastics from nearby Grays River eruptive centers (e.g., Mt. Solo and Rocky Point). The lower 100 meters of the Coal Creek section (informal unit 1, Chron 18r) consists of micaceous, lithic arkosic sandstone and siltstone and minor coals, was deposited as part of a highstand system tract (HST) at the base of 3rd order cycle number 3. This unit consists of four dominantly tidal shoaling-upward arkosic sandstone parasequences reflecting upper shoreface to delta plain depositional environments. The overlying unit 2 (Chron 18n) is defined by abundant Grays River basalt volcaniclastic interbeds that intertongue with Cowlitz lithic arkoses. This unit represents the latter part of 3rd order cycle 3, and consists of mostly fining- and thinning-upward parasequences of middle shoreface to delta plain successions of an aggradational to transgressive parasequence set. Near the top of unit 2 is a maximum marine flooding surface depositing lower shoreface lithic arkosic sandstone to shelf siltstones over upper shoreface micaceous lithic arkose. Unit 3 comprises 3rd order cycle 4 (Chron 17r), a lowstand system tract, and consists of 6 mostly fining- and thinning-upward parasequences of lower shoreface to delta plain facies associations. A parasequence or erosional boundary at the base of unit 5 (Chron 17r) consists of submarine channel-fill scoured into underlying micaceous siltstones, produced during a lowstand system tract (LST) of 3rd order cycle 5. This deep marine channel-fill sequence is overlain by thinlybedded to laminated overbank distal turbidites and hemipelagic siltstones that define the top of the Coal Creek section. These 5 informal units in Coal Creek lithologically and chronologically correlate to 5 similar informal units defined by Payne (1998) in the type section of Cowlitz Formation in Olequa Creek near Vader -30 km to the north. Middle Eocene Grays River Volcanics of the study area are mapped as two separate units: a lower unit over 150 meters thick in places, consisting of subaerial basaltic flows and invasive flows (Tgvl), intrusions (Tgvis and Tgvid), and volcaniclastics (Tgvsl); and an upper unit consisting of commonly mollusk-bearing, shallow marine basaltic sedimentary interbeds that intertongue with the Cowlitz Formation (Tgvs2), particularly Cowlitz unit 2 of the Coal Creek section. These volcaniclastic deposits are intrabasinal, derived from volcanic highlands to the west and northwest, and local phreatomagmatic tuff cones. The lower Grays River volcaniclastic unit typically overlies Grays River flows in the study area and is divided into 5 informal facies. Geochemically, Grays River flows in the study area fall within normal parameters (3 to 4% TiO2 and high iron tholeiitic basalts). However, basalt flows and bedded scoriaceous breccias near Rocky Point are anomalously low in TiO2 and are considered in this study to be a separate volcanic subunit (Rocky Point Basalts), time equivalent to and interfingering with Grays River lavas, but may represent mixing with shallower western Cascade calc-alkaline magma. Over 60 younger Grays River dikes intrude the Cowlitz Formation in Coal Creek. A dike low in the Coal Creek section is dated at 40 ± 0.36 Ma, and an invasive flow at Mt. Solo is dated at 36.98 ±.78 Ma. Volcanics capping the hills east of the Cowlitz River are chemically distinct as slightly younger western Cascade basaltic andesite flows, and two dikes east of the river are chemically distinct as western Cascade andesite. Overlying Grays River Volcanics and Cowlitz Formation in much of the study area, are clayey and commonly tuffaceous siltstones and silty sandstones, possibly of the late Eocene-early Oligocene Toutle Formation, a new unit to this area. The Toutle Formation is a mixture of wave and stream reworked micaceous and arkosic Cowlitz Formation and fresh silicic pyroclastic ash and pumice from the active western Cascade arc. An angular unconformity separates the Paleogene Grays River Volcanics, Cowlitz Formation, and Toutle Formation from the early to middle Miocene Columbia River Basalt Group. Based on lithology, geochemistry, stratigraphic relationships, and magnetic polarity, 6 individual Columbia River Basalt flows have been mapped in this study. The three lower Grande Ronde flows are of normal polarity and Ortley low MgO chemical composition. The lowermost flow (N2 Ortley #1) is absent in the Columbia Heights area, low MgO, about 10 meters thick and consists of pillow-palagonite sequences in the upper quarry on Mt. Solo. Aphyric N2 Ortley flow #2 is over 35 meters thick with well-developed upper and lower colonnade, and of intermediate MgO. N2 Ortley flow #3 is pillow-palagonite in the Storedahl Quarry and low MgO. A -4-meter thick tuffaceous overbank siltstone and basalt conglomeratic channel interbed separates the three low MgO Ortley flows from the overlying high MgO N2 Grande Ronde Sentinel Bluffs flow. A single exposure of well-developed large colonnade with sparse 1 cm labradorite laths, and reddish oxidized soil, defines the N Sand Hollow flow of the Frenchman Springs Member of the Wanapum Formation. The overlying Pomona Member is mapped based on previous work by other authors. Pliocene gravels and arkosic sand of the Troutdale Formation form upland terrace deposits up to 100 meters thick in southern parts of the study area, and represent the uplifted paleo-thalweg and overbank flood deposits of the downcutting, antecedent ancestral Columbia River. Well-rounded clasts are a mixture of extrabasinal granitic and metamorphic quartzite, and intrabasinal porphyritic basaltic andesite, dacite, and basalt from the western Cascades and Columbia River Basalts. Troutdale terrace gravels grade northward into contemporaneous volcanic pebble and cobble gravel terrace deposits produced along the ancestral Cowlitz River that are dominantly composed of porphyritic andesite gravel and volcanic sand from the western Cascades. Lower terraces along the Cowlitz River were deposited by the late Pleistocene Missoula Floods. All of these unconsolidated to semiconsolidated gravels and sands are prone to landslides, and the Aldercrest-Banyon landslide, the second worst landslide disaster in American history, occurred in the Troutdale Formation gravels. After eruption of the Grays River Volcanics and deposition of the Cowlitz Formation, the forearc underwent a period of transtension in the late-middle Eocene related to magmatic upwelling and reorganization of the subducting Farallon Plate. This event produced a northwest-trending set of oblique slip normal faults, along which Grays River dikes intruded. Starting in the early Miocene the region underwent a transpressional event, reactivating many of the northwest-trending faults, and producing the Columbia Heights Anticline, Hazel Dell Syncline, the Coal Creek Fault, and the Kelso Fault Zone. The paleotopography resulting from this event was stream eroded to a nearly flat plain before emplacement of the Columbia River Basalts, which are nearly horizontal today. Continued offset along the northwest-trending fault set has also offset the Columbia River Basalts. Continued oblique slip post-Miocene broad arching of the Coast Range and downcutting by the Columbia and Cowlitz Rivers has resulted in Pliocene and Pleistocene terraces, and produced an east-west fault set that offsets all earlier structural features. Close