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• 241. [Article] Managing Marine Resources in Oregon’s Territorial Sea and Ocean Stewardship Area: The importance of environmental information in planning and decision making

  Oregon has a strong framework for ocean planning rooted in the adoption of Oregon’s Ocean Resources Goal 19 in 1976. Goal 19 establishes that it is the State of Oregon’s policy to conserve marine resources ...

  Citation × Citation Citation Abstract Copy Title: Managing Marine Resources in Oregon’s Territorial Sea and Ocean Stewardship Area: The importance of environmental information in planning and decision making Author: Snow, Patty Oregon has a strong framework for ocean planning rooted in the adoption of Oregon’s Ocean Resources Goal 19 in 1976. Goal 19 establishes that it is the State of Oregon’s policy to conserve marine resources and ecological functions for the purpose of providing long-term ecological, economic, and social value and benefits to future generations. To this end, all actions by local, state and federal agencies that are likely to affect the ocean resources and uses of Oregon’s territorial sea are to be developed and conducted to conserve marine resources and ecological functions. Higher priority is given to the protection of renewable marine resources (living marine organisms) than to the development of non-renewable ocean resources. This ocean planning framework was further codified by the Oregon Ocean Resource Management Act (ORS 196.405 to 196.485) passed in 1991 which created the Oregon ocean governance structure. The Oregon Territorial Sea Plan (TSP) which contains specific polices for state ocean management was originally adopted in 1994. The TSP was modified in 2009 to address policies for managing marine renewable energy development. A process is underway to use spatial planning techniques to identify areas appropriate for marine renewable energy development; adoption of these amendments to the TSP is anticipated in January 2013. Goal 19 also establishes the policy framework for the Ocean Stewardship Area which is defined to include the state’s territorial sea (out to three nautical miles), the continental margin seaward to the toe of the continental slope, and adjacent ocean areas. The Ocean Stewardship area is further addressed in the TSP. Goal 19, the Oregon Ocean Resources Management Act, and the TSP all state that prior to taking an action that is likely to affect ocean resources or uses of Oregon’s territorial sea, state and federal agencies are required to assess the reasonably foreseeable adverse effects of the action. The effects assessment is also to address reasonably foreseeable adverse effects on Oregon’s estuaries and shorelands. The information and protection requirements outlined below apply both on a planning scale (i.e., Territorial sea Plan) and on a permit-by-permit basis (i.e., OPT permit). Information is needed for the territorial sea, the ocean stewardship area and the outer continental shelf. Oregon’s Ocean Resources Goal 19, the Oregon Resources Management Act, and the TSP all require the protection of certain resources: a. Renewable marine resources; b. Biological diversity of marine life and the functional integrity of the marine ecosystem; c. Important marine habitat including areas: 1. Important to the biological viability of commercially or recreationally caught species or that support important food or prey species for commercially or recreationally caught species; or 2. needed to assure the survival of threatened or endangered species; 3. ecologically significant to maintain ecosystem structure, biological productivity, and biological diversity; 4. essential to the life-history or behavior of marine organisms; or 5. especially vulnerable because of size, composition, or location in relation to chemical or other pollutants, noise, physical disturbance, alteration, or harvest; or 6. unique or of limited range within the state: and d. Areas important to fisheries, which are: 1. areas of high catch; or 2. areas where highly valued fish are caught even if in low abundance or by few fishers; or 3. areas that are important on a seasonal basis; or 4. areas important to commercial or recreational fishing activities, including those of individual ports or particular fleets; or 5. habitat areas that support food or prey species important to commercially and recreationally caught fish and shellfish species. 6. Agencies are also to protect and encourage beneficial uses of ocean resources such as navigation, food production, recreation, aesthetic enjoyment, and uses of the seafloor provided that the activities do not adversely affect the resources protected in 1-4 above. To support the TSP spatial planning process and meet Goal 19 planning information requirements, the State of Oregon has developed a spatial decision support tool called MarineMap. It displays Oregon’s Ocean GIS database online and currently encompasses over 200 data layers including: a. Commercial and recreational fisheries data collected through local advisory committees for areas important to fisheries (Winter 2011); b. Ecological data collected by the Oregon Department of Fish and Wildlife (Summer 2011); c. Seafloor bathymetric and image data (Summer 2011); d. Recreational ocean use determined by on-line surveys (Fall 2010); e. Visual assessment inventory information (Summer 2012); f. Other spatial data on human uses, managed resources, physical conditions, and shoreland facilities (Fall 2010). This information has been used as part of the geospatial analysis to develop areas to be protected by Goal 19 in the current TSP mapping process. Currently, the draft recommendation is for six areas or zones: a. Renewable Energy Exclusion Area (REEA); b. Proprietary Use and Management Area (PUMA); c. Resources and Uses Conservation Area (RUCA); d. Resources and Uses Management Area (RUMA); e. Renewable Energy Facility Suitability Study Area (REFSSA); f. Renewable Energy Permit Area (REPA). Standards are the most stringent in the conservation area and least stringent in the study area. In addition, the draft recommendations include two overlay zones and screening standards that would apply across the territorial sea: 1. Visual Resource Area Overlay; 2. Marine Recreation Area Overlay. Information will be needed for permit applications in each of these zones but will be more extensive in conservation areas to ensure that important resources are protected. Permits for marine renewable energy projects in the future will be subject to different screening standards depending on what zone or area they are proposed in. While Oregon has created an innovative marine spatial planning decision support tool, the state continues to need additional information to ground truth assumptions, fill in information gaps, reduce uncertainties, and provide expert opinions. In addition, the state is working with other West Coast states to create a regional data framework that will facilitate regional decision-making and planning efforts. Title: Managing Marine Resources in Oregon’s Territorial Sea and Ocean Stewardship Area: The importance of environmental information in planning and decision making Author: Snow, Patty Oregon has a strong framework for ocean planning rooted in the adoption of Oregon’s Ocean Resources Goal 19 in 1976. Goal 19 establishes that it is the State of Oregon’s policy to conserve marine resources and ecological functions for the purpose of providing long-term ecological, economic, and social value and benefits to future generations. To this end, all actions by local, state and federal agencies that are likely to affect the ocean resources and uses of Oregon’s territorial sea are to be developed and conducted to conserve marine resources and ecological functions. Higher priority is given to the protection of renewable marine resources (living marine organisms) than to the development of non-renewable ocean resources. This ocean planning framework was further codified by the Oregon Ocean Resource Management Act (ORS 196.405 to 196.485) passed in 1991 which created the Oregon ocean governance structure. The Oregon Territorial Sea Plan (TSP) which contains specific polices for state ocean management was originally adopted in 1994. The TSP was modified in 2009 to address policies for managing marine renewable energy development. A process is underway to use spatial planning techniques to identify areas appropriate for marine renewable energy development; adoption of these amendments to the TSP is anticipated in January 2013. Goal 19 also establishes the policy framework for the Ocean Stewardship Area which is defined to include the state’s territorial sea (out to three nautical miles), the continental margin seaward to the toe of the continental slope, and adjacent ocean areas. The Ocean Stewardship area is further addressed in the TSP. Goal 19, the Oregon Ocean Resources Management Act, and the TSP all state that prior to taking an action that is likely to affect ocean resources or uses of Oregon’s territorial sea, state and federal agencies are required to assess the reasonably foreseeable adverse effects of the action. The effects assessment is also to address reasonably foreseeable adverse effects on Oregon’s estuaries and shorelands. The information and protection requirements outlined below apply both on a planning scale (i.e., Territorial sea Plan) and on a permit-by-permit basis (i.e., OPT permit). Information is needed for the territorial sea, the ocean stewardship area and the outer continental shelf. Oregon’s Ocean Resources Goal 19, the Oregon Resources Management Act, and the TSP all require the protection of certain resources: a. Renewable marine resources; b. Biological diversity of marine life and the functional integrity of the marine ecosystem; c. Important marine habitat including areas: 1. Important to the biological viability of commercially or recreationally caught species or that support important food or prey species for commercially or recreationally caught species; or 2. needed to assure the survival of threatened or endangered species; 3. ecologically significant to maintain ecosystem structure, biological productivity, and biological diversity; 4. essential to the life-history or behavior of marine organisms; or 5. especially vulnerable because of size, composition, or location in relation to chemical or other pollutants, noise, physical disturbance, alteration, or harvest; or 6. unique or of limited range within the state: and d. Areas important to fisheries, which are: 1. areas of high catch; or 2. areas where highly valued fish are caught even if in low abundance or by few fishers; or 3. areas that are important on a seasonal basis; or 4. areas important to commercial or recreational fishing activities, including those of individual ports or particular fleets; or 5. habitat areas that support food or prey species important to commercially and recreationally caught fish and shellfish species. 6. Agencies are also to protect and encourage beneficial uses of ocean resources such as navigation, food production, recreation, aesthetic enjoyment, and uses of the seafloor provided that the activities do not adversely affect the resources protected in 1-4 above. To support the TSP spatial planning process and meet Goal 19 planning information requirements, the State of Oregon has developed a spatial decision support tool called MarineMap. It displays Oregon’s Ocean GIS database online and currently encompasses over 200 data layers including: a. Commercial and recreational fisheries data collected through local advisory committees for areas important to fisheries (Winter 2011); b. Ecological data collected by the Oregon Department of Fish and Wildlife (Summer 2011); c. Seafloor bathymetric and image data (Summer 2011); d. Recreational ocean use determined by on-line surveys (Fall 2010); e. Visual assessment inventory information (Summer 2012); f. Other spatial data on human uses, managed resources, physical conditions, and shoreland facilities (Fall 2010). This information has been used as part of the geospatial analysis to develop areas to be protected by Goal 19 in the current TSP mapping process. Currently, the draft recommendation is for six areas or zones: a. Renewable Energy Exclusion Area (REEA); b. Proprietary Use and Management Area (PUMA); c. Resources and Uses Conservation Area (RUCA); d. Resources and Uses Management Area (RUMA); e. Renewable Energy Facility Suitability Study Area (REFSSA); f. Renewable Energy Permit Area (REPA). Standards are the most stringent in the conservation area and least stringent in the study area. In addition, the draft recommendations include two overlay zones and screening standards that would apply across the territorial sea: 1. Visual Resource Area Overlay; 2. Marine Recreation Area Overlay. Information will be needed for permit applications in each of these zones but will be more extensive in conservation areas to ensure that important resources are protected. Permits for marine renewable energy projects in the future will be subject to different screening standards depending on what zone or area they are proposed in. While Oregon has created an innovative marine spatial planning decision support tool, the state continues to need additional information to ground truth assumptions, fill in information gaps, reduce uncertainties, and provide expert opinions. In addition, the state is working with other West Coast states to create a regional data framework that will facilitate regional decision-making and planning efforts. Close

• 242. [Article] Approaches for Characterizing Plant Physiological Responses to Environmental Stress

  It is uncertain how predicted changes in climate will impact vegetation responses and plant species’ distributions because the physiological mechanisms underlying thresholds for damage are not well understood, ...

  Citation × Citation Citation Abstract Copy Title: Approaches for Characterizing Plant Physiological Responses to Environmental Stress Author: Marias, Danielle E. It is uncertain how predicted changes in climate will impact vegetation responses and plant species’ distributions because the physiological mechanisms underlying thresholds for damage are not well understood, and responses to stress vary by functional type and developmental stage. Thus, it is crucial to investigate physiological responses to heat and drought stress on multiple species, populations, and growth stages with diverse approaches. In this dissertation, I employ a suite of physiological and modeling methods to inform our knowledge of plant physiological responses to environmental stress in Coffea arabica saplings, Pseudotsuga mensizeii (PSME) and Pinus ponderosa (PIPO) seedlings, and old-growth PIPO. In Chapter 2, I evaluate the effect of leaf age and methodology on the thermotolerance or heat tolerance of C. arabica leaf discs using chlorophyll fluorescence and electrolyte leakage methods. I found that mature leaves were more heat tolerant than expanding leaves, longer time between temperature exposure and measurement yielded more accurate thermotolerance assessments, and photochemistry was more heat-sensitive than cell membranes. To complement the second chapter investigating heat stress responses on detached leaf discs, Chapter 3 examines the effect of leaf age and heat stress duration (45 min or 90 min) on whole-plant physiological responses and capacity to recover in C. arabica by monitoring chlorophyll fluorescence (F[subscript V]/F[subscript M]), gas exchange, and foliar non-structural carbohydrate (NSC) dynamics in situ in response to a simulated heat wave (49°C) in a growth chamber. I found that the 90 min treatment resulted in greater photosynthetic damage and slower recovery than the 45 min treatment, expanding leaves recovered more slowly than in mature leaves, and both heat treatments inhibited flowering. A leaf energy balance model demonstrated that heat stress would be exacerbated by drought-induced stomatal closure. Heat treatment duration significantly impacted NSC dynamics that were closely related to reproduction and repair. Because seedling establishment governs species’ distributions, and because seedlings are particularly threatened by high temperatures at the soil surface, in Chapter 4 I examined the thermotolerance and heat stress responses of PIPO and PSME seedling populations from contrasting climates. Unexpectedly, I found that PSME was more heat tolerant the PIPO. I also monitored physiological recovery after exposure to a simulated heat wave (45°C) by measuring photosynthesis, F[subscript V]/F[subscript M], foliar NSC, and carbon stable isotope ratios (proxy for intrinsic water use efficiency, iWUE). Heat stress responses were consistent with phenotypic plasticity and reflected the conditions under which the plants were grown, while iWUE, a measure of potential drought resistance, was consistent with ecotypic differentiation and the climates from which the seedlings originated. To investigate responses to environmental stress on larger temporal and spatial scales without the challenges of making repeated physiological measurements on old-growth trees, in Chapter 5 I used long-term trajectories of tree-ring growth and carbon and oxygen isotopes of tree-ring cellulose (δ¹³Ccell, and δ¹⁸Ocell) to successfully predict the stand characteristics of two sets (upland, riparian) of old-growth PIPO using the Physiological Principles in Predicting Growth (3-PG) model, the δ¹³Ccell submodel, and a δ¹⁸Ocell submodel added by me. The expanded model helped to explain physiological drivers underlying the different tree-ring growth, δ¹³Ccell, and δ¹⁸Ocell trajectories measured at the upland and riparian sites. The combination of both δ¹⁸O and δ¹³Ccell submodels provided a useful and novel way to constrain 3-PG. This dissertation demonstrates an innovative strategy of applying diverse approaches to understand the physiological mechanisms behind vegetation responses to environmental stress. Title: Approaches for Characterizing Plant Physiological Responses to Environmental Stress Author: Marias, Danielle E. It is uncertain how predicted changes in climate will impact vegetation responses and plant species’ distributions because the physiological mechanisms underlying thresholds for damage are not well understood, and responses to stress vary by functional type and developmental stage. Thus, it is crucial to investigate physiological responses to heat and drought stress on multiple species, populations, and growth stages with diverse approaches. In this dissertation, I employ a suite of physiological and modeling methods to inform our knowledge of plant physiological responses to environmental stress in Coffea arabica saplings, Pseudotsuga mensizeii (PSME) and Pinus ponderosa (PIPO) seedlings, and old-growth PIPO. In Chapter 2, I evaluate the effect of leaf age and methodology on the thermotolerance or heat tolerance of C. arabica leaf discs using chlorophyll fluorescence and electrolyte leakage methods. I found that mature leaves were more heat tolerant than expanding leaves, longer time between temperature exposure and measurement yielded more accurate thermotolerance assessments, and photochemistry was more heat-sensitive than cell membranes. To complement the second chapter investigating heat stress responses on detached leaf discs, Chapter 3 examines the effect of leaf age and heat stress duration (45 min or 90 min) on whole-plant physiological responses and capacity to recover in C. arabica by monitoring chlorophyll fluorescence (F[subscript V]/F[subscript M]), gas exchange, and foliar non-structural carbohydrate (NSC) dynamics in situ in response to a simulated heat wave (49°C) in a growth chamber. I found that the 90 min treatment resulted in greater photosynthetic damage and slower recovery than the 45 min treatment, expanding leaves recovered more slowly than in mature leaves, and both heat treatments inhibited flowering. A leaf energy balance model demonstrated that heat stress would be exacerbated by drought-induced stomatal closure. Heat treatment duration significantly impacted NSC dynamics that were closely related to reproduction and repair. Because seedling establishment governs species’ distributions, and because seedlings are particularly threatened by high temperatures at the soil surface, in Chapter 4 I examined the thermotolerance and heat stress responses of PIPO and PSME seedling populations from contrasting climates. Unexpectedly, I found that PSME was more heat tolerant the PIPO. I also monitored physiological recovery after exposure to a simulated heat wave (45°C) by measuring photosynthesis, F[subscript V]/F[subscript M], foliar NSC, and carbon stable isotope ratios (proxy for intrinsic water use efficiency, iWUE). Heat stress responses were consistent with phenotypic plasticity and reflected the conditions under which the plants were grown, while iWUE, a measure of potential drought resistance, was consistent with ecotypic differentiation and the climates from which the seedlings originated. To investigate responses to environmental stress on larger temporal and spatial scales without the challenges of making repeated physiological measurements on old-growth trees, in Chapter 5 I used long-term trajectories of tree-ring growth and carbon and oxygen isotopes of tree-ring cellulose (δ¹³Ccell, and δ¹⁸Ocell) to successfully predict the stand characteristics of two sets (upland, riparian) of old-growth PIPO using the Physiological Principles in Predicting Growth (3-PG) model, the δ¹³Ccell submodel, and a δ¹⁸Ocell submodel added by me. The expanded model helped to explain physiological drivers underlying the different tree-ring growth, δ¹³Ccell, and δ¹⁸Ocell trajectories measured at the upland and riparian sites. The combination of both δ¹⁸O and δ¹³Ccell submodels provided a useful and novel way to constrain 3-PG. This dissertation demonstrates an innovative strategy of applying diverse approaches to understand the physiological mechanisms behind vegetation responses to environmental stress. Close

• 243. [Article] Response of small mammal mycophagy to varying levels and patterns of green-tree retention in mature forests of western Oregon and Washington

  The Demonstration of Ecosystem Management Options (DEMO) study is a large-scale, multi-year, interdisciplinary project examining the effects of various levels and patterns of green-tree retention on multiple ...

  Citation × Citation Citation Abstract Copy Title: Response of small mammal mycophagy to varying levels and patterns of green-tree retention in mature forests of western Oregon and Washington Author: Jacobs, Katherine M. The Demonstration of Ecosystem Management Options (DEMO) study is a large-scale, multi-year, interdisciplinary project examining the effects of various levels and patterns of green-tree retention on multiple forest features. Six retention levels and patterns were examined and replicated across six blocks of predominately Douglas-fir forested land in western Oregon and Washington. As part of the DEMO study, this research focuses on the effects of these silviculture activities on small mammal mycophagy. The diets of three small mammal groups were examined: squirrels (the northern flying squirrel, Glaucomys sabrinus), chipmunks (Townsend's chipmunk - Tarnias townsendii, and the Siskiyou chipmunk - T. siskiyou), and voles (the western and southern red-backed voles - Clethrionomys calfornicus and C. gapperi). These animals are vital fungal spore dispersers and forest prey. Fecal pellet analysis was used as a non-lethal method of examining the diets of these mycophagous mammals. Fecal samples were collected from these animals before and after the application of treatments. Pretreatment diet data was utilized for a diet comparison among the animal genera. The change in the frequencies for the common truffle genera, plant material, and total cumulative number of genera were compared using an analysis of variance to measure the effect of each treatment on the diets of the study animals. The pre-treatment fungal diets of the study animals showed significant differences among genera. Glaucomys sabrinus fecal samples contained higher frequencies of Gautieria and Leucogaster spores than either Clethrionornys or Tamias samples. The diet of the Tamias spp. contained higher frequencies of plant material than G. sabrinus or Clethrionomys, emphasizing the more diverse diet of this animal genus. G. sabrinus samples contained the highest mean number of truffle genera per sample and consistently contained a high frequency of the four common truffle genera. Moderately high frequencies of the common truffle genera were conimon in the Clethrionomys samples. Only the genus Rhizopogon was commonly found in high frequencies in the Tamias samples. The frequency of Rhizopogon spores was consistently greater than 95% in the pre-treatment diets of all animal genera. Treatment effects were found for different diet items for each animal genus. The mean total cumulative number of truffle genera in the diet of the study animals showed little change. The harvesting of trees appears to negatively affect the frequency of Rhizopogon spores in the diet of Clethrionomys, potentially reflecting the reduced ability of these animals to forage for Rhizopogon truffles and a reduction in Rhizopogon truffle abundance or frequency, especially in the 15% aggregated retention treatment. The retention of trees in isolated aggregates restricts the movement of Clethrionomys within the treatment and the abundance of edge on the aggregates may further restrict Clethrionornys to the center of the aggregates. Competition would be increased within these aggregates where animals are concentrated and the resource may be even more limited. In the diet of G. sabrinus, the frequency of Gautieria spores significantly decreased in the 40% aggregated retention treatment and increased in the 40% dispersed retention treatment. The retention of trees in aggregates may limit the ability of G. sabrinus to move and forage between aggregates and into adjacent habitat. However, in the dispersed retention treatments, adequate travel routes are still available and G. sabrinus could forage throughout the treatment and in to adjacent habitat, thus reducing the impact of the reduction of truffle biomass within a stand. The diet of the Tamias spp. showed little change in response to the treatments. The wide diversity of habitats that Tamias utilize may extend the ability of this animal to find and compete for truffles even as they decreased locally, until a large decrease in biomass occurred. The sporocarp biomass data (D. Luoma, unpublished data) showed that overall truffle biomass declined, whereas consumption of truffles by these small mammals largely stayed the same. This suggests that the animals are compensating for a locally declining food source by altering their foraging behavior. The long term effects of this behavioral compensation on energetic s and population dynamics is unknown. Title: Response of small mammal mycophagy to varying levels and patterns of green-tree retention in mature forests of western Oregon and Washington Author: Jacobs, Katherine M. The Demonstration of Ecosystem Management Options (DEMO) study is a large-scale, multi-year, interdisciplinary project examining the effects of various levels and patterns of green-tree retention on multiple forest features. Six retention levels and patterns were examined and replicated across six blocks of predominately Douglas-fir forested land in western Oregon and Washington. As part of the DEMO study, this research focuses on the effects of these silviculture activities on small mammal mycophagy. The diets of three small mammal groups were examined: squirrels (the northern flying squirrel, Glaucomys sabrinus), chipmunks (Townsend's chipmunk - Tarnias townsendii, and the Siskiyou chipmunk - T. siskiyou), and voles (the western and southern red-backed voles - Clethrionomys calfornicus and C. gapperi). These animals are vital fungal spore dispersers and forest prey. Fecal pellet analysis was used as a non-lethal method of examining the diets of these mycophagous mammals. Fecal samples were collected from these animals before and after the application of treatments. Pretreatment diet data was utilized for a diet comparison among the animal genera. The change in the frequencies for the common truffle genera, plant material, and total cumulative number of genera were compared using an analysis of variance to measure the effect of each treatment on the diets of the study animals. The pre-treatment fungal diets of the study animals showed significant differences among genera. Glaucomys sabrinus fecal samples contained higher frequencies of Gautieria and Leucogaster spores than either Clethrionornys or Tamias samples. The diet of the Tamias spp. contained higher frequencies of plant material than G. sabrinus or Clethrionomys, emphasizing the more diverse diet of this animal genus. G. sabrinus samples contained the highest mean number of truffle genera per sample and consistently contained a high frequency of the four common truffle genera. Moderately high frequencies of the common truffle genera were conimon in the Clethrionomys samples. Only the genus Rhizopogon was commonly found in high frequencies in the Tamias samples. The frequency of Rhizopogon spores was consistently greater than 95% in the pre-treatment diets of all animal genera. Treatment effects were found for different diet items for each animal genus. The mean total cumulative number of truffle genera in the diet of the study animals showed little change. The harvesting of trees appears to negatively affect the frequency of Rhizopogon spores in the diet of Clethrionomys, potentially reflecting the reduced ability of these animals to forage for Rhizopogon truffles and a reduction in Rhizopogon truffle abundance or frequency, especially in the 15% aggregated retention treatment. The retention of trees in isolated aggregates restricts the movement of Clethrionomys within the treatment and the abundance of edge on the aggregates may further restrict Clethrionornys to the center of the aggregates. Competition would be increased within these aggregates where animals are concentrated and the resource may be even more limited. In the diet of G. sabrinus, the frequency of Gautieria spores significantly decreased in the 40% aggregated retention treatment and increased in the 40% dispersed retention treatment. The retention of trees in aggregates may limit the ability of G. sabrinus to move and forage between aggregates and into adjacent habitat. However, in the dispersed retention treatments, adequate travel routes are still available and G. sabrinus could forage throughout the treatment and in to adjacent habitat, thus reducing the impact of the reduction of truffle biomass within a stand. The diet of the Tamias spp. showed little change in response to the treatments. The wide diversity of habitats that Tamias utilize may extend the ability of this animal to find and compete for truffles even as they decreased locally, until a large decrease in biomass occurred. The sporocarp biomass data (D. Luoma, unpublished data) showed that overall truffle biomass declined, whereas consumption of truffles by these small mammals largely stayed the same. This suggests that the animals are compensating for a locally declining food source by altering their foraging behavior. The long term effects of this behavioral compensation on energetic s and population dynamics is unknown. Close

• 244. [Article] Giant otters (Pteronura brasiliensis) and humans in the lower Yasuní Basin, Ecuador : spacio-temporal activity patterns and their relevance for conservation

  Giant otters (Pteronura brasiliensis) and humans in the Lower Yasuní Basin (Ecuador) have similar food and space requirements: they consume comparable arrays of fish species, and they use similar aquatic ...

  Citation × Citation Citation Abstract Copy Title: Giant otters (Pteronura brasiliensis) and humans in the lower Yasuní Basin, Ecuador : spacio-temporal activity patterns and their relevance for conservation Author: Carrera-Ubidia, Paola M. Giant otters (Pteronura brasiliensis) and humans in the Lower Yasuní Basin (Ecuador) have similar food and space requirements: they consume comparable arrays of fish species, and they use similar aquatic and terrestrial habitats. Resource partitioning could facilitate coexistence by allowing each species exclusive access to some resources. My research examines the correlations between the use of spatial resources by giant otters and humans and the hydrological pulse of their ecosystem. My objectives were (1) to estimate the extent of terrestrial and aquatic habitat available for giant otters and humans;(2) to recognize the main patterns of space occupancy and its overlap between them; (3)to explain these patterns in relation to natural gradients in the watershed; (4) to describe the giant otter’s diet; and (5) to depict the foraging activities of giant otters and humans relative to the distribution of prey. Between October 2004 and March 2005, I surveyed the Jatuncocha and Tambococha Creeks (Yasuní National Park) for direct and indirect signs of giant otters and humans, and I collected giant otter scat. Habitat availability was estimated by a geo-referenced map model that integrated virtual and field data, portraying four seasonal scenarios. Space use overlaps between giant otters and humans are a function of water level and the distance between terrestrial and aquatic habitats. The floodplain comprises 43% of the total study area during the flooding season, and is reduced to 25% of the total area at minimum water levels. Polygons obtained containing suitable habitat for giant otters are in average 41% larger than those obtained for humans; these contain areas that are inaccessible to humans (isolated pools and swamps, tributaries, and the upper portions of the main channel). Differences in space availability for and use by giant otters and humans depend on water level fluctuations. Area occupancy by both species is proportional to the estimated availability; but more so for giant otters, as humans increase area occupancy during the driest periods. Giant otter activity was primarily concentrated around the largest tributaries of each creek, and secondarily wherever the distance between suitable terrestrial and aquatic habitat was smaller. Human activity signs were distributed along the hydrographical gradient, i.e. in the lower portion of the Jatuncocha System (lagoon) or in the middle portion of the Tambococha Creek (large tributary). To identify correlations between habitat use by giant otters and humans and prey availability, I analyzed scat samples and collected fish along several creek stretches. Giant otters consumed at least 47 of the 73 species available for them. Identifiable hard parts in the scat samples consisted primarily of Hoplias malabaricus (11.3%), Hypselecara termporalis (5.3%), Acestrorrhynchus sp. and Prochilodus nigricans (4.9% each). Foraging activity of giant otters was positively correlated with fish abundance and relative diversity, with some exceptions. Human activity patterns were related to fish abundance and diversity in Tambococha, but showed less correlation to fish distribution in Jatuncocha. Overlap in resource availability and habitat use by otters and humans is highly variable. In the floodplain, extent and depth are critical variables that determine the distribution of resources in time and space, as well as the amount of resource partitioning possible. Competitive interactions during stressful conditions could be reduced by ensuring the availability of exclusive resources for giant otters during the driest periods, allocating suitable habitats within a short distance from one another along the longitudinal gradient of each watershed. Locally adapted and biologically sound regulations within this and comparable areas of the YNP could promote the persistence of giant otters without compromising the well-being of the local human inhabitants. Title: Giant otters (Pteronura brasiliensis) and humans in the lower Yasuní Basin, Ecuador : spacio-temporal activity patterns and their relevance for conservation Author: Carrera-Ubidia, Paola M. Giant otters (Pteronura brasiliensis) and humans in the Lower Yasuní Basin (Ecuador) have similar food and space requirements: they consume comparable arrays of fish species, and they use similar aquatic and terrestrial habitats. Resource partitioning could facilitate coexistence by allowing each species exclusive access to some resources. My research examines the correlations between the use of spatial resources by giant otters and humans and the hydrological pulse of their ecosystem. My objectives were (1) to estimate the extent of terrestrial and aquatic habitat available for giant otters and humans;(2) to recognize the main patterns of space occupancy and its overlap between them; (3)to explain these patterns in relation to natural gradients in the watershed; (4) to describe the giant otter’s diet; and (5) to depict the foraging activities of giant otters and humans relative to the distribution of prey. Between October 2004 and March 2005, I surveyed the Jatuncocha and Tambococha Creeks (Yasuní National Park) for direct and indirect signs of giant otters and humans, and I collected giant otter scat. Habitat availability was estimated by a geo-referenced map model that integrated virtual and field data, portraying four seasonal scenarios. Space use overlaps between giant otters and humans are a function of water level and the distance between terrestrial and aquatic habitats. The floodplain comprises 43% of the total study area during the flooding season, and is reduced to 25% of the total area at minimum water levels. Polygons obtained containing suitable habitat for giant otters are in average 41% larger than those obtained for humans; these contain areas that are inaccessible to humans (isolated pools and swamps, tributaries, and the upper portions of the main channel). Differences in space availability for and use by giant otters and humans depend on water level fluctuations. Area occupancy by both species is proportional to the estimated availability; but more so for giant otters, as humans increase area occupancy during the driest periods. Giant otter activity was primarily concentrated around the largest tributaries of each creek, and secondarily wherever the distance between suitable terrestrial and aquatic habitat was smaller. Human activity signs were distributed along the hydrographical gradient, i.e. in the lower portion of the Jatuncocha System (lagoon) or in the middle portion of the Tambococha Creek (large tributary). To identify correlations between habitat use by giant otters and humans and prey availability, I analyzed scat samples and collected fish along several creek stretches. Giant otters consumed at least 47 of the 73 species available for them. Identifiable hard parts in the scat samples consisted primarily of Hoplias malabaricus (11.3%), Hypselecara termporalis (5.3%), Acestrorrhynchus sp. and Prochilodus nigricans (4.9% each). Foraging activity of giant otters was positively correlated with fish abundance and relative diversity, with some exceptions. Human activity patterns were related to fish abundance and diversity in Tambococha, but showed less correlation to fish distribution in Jatuncocha. Overlap in resource availability and habitat use by otters and humans is highly variable. In the floodplain, extent and depth are critical variables that determine the distribution of resources in time and space, as well as the amount of resource partitioning possible. Competitive interactions during stressful conditions could be reduced by ensuring the availability of exclusive resources for giant otters during the driest periods, allocating suitable habitats within a short distance from one another along the longitudinal gradient of each watershed. Locally adapted and biologically sound regulations within this and comparable areas of the YNP could promote the persistence of giant otters without compromising the well-being of the local human inhabitants. Close

• 245. [Article] Non-native and native plant species distributions and variability along an elevation gradient in the Wallowa Mountains, Oregon

  Invasion by non-native plants into natural areas is an important component of global change that threatens biodiversity and ecosystem structure and function. Mountains are currently among the least invaded ...

  Citation × Citation Citation Abstract Copy Title: Non-native and native plant species distributions and variability along an elevation gradient in the Wallowa Mountains, Oregon Author: Averett, Joshua P. Invasion by non-native plants into natural areas is an important component of global change that threatens biodiversity and ecosystem structure and function. Mountains are currently among the least invaded ecosystems, however, these biodiversity hotspots are increasingly under threat of exotic plant invasion. Evaluation of plant species distribution patterns in mountain ecosystems can provide insight into dominant processes of plant invasion and inform management to reduce the spread of non-native plants in mountains. The objectives of this study were to: 1) evaluate the main drivers of plant invasions in the Wallowa Mountain Range of northeastern Oregon, and the extent patterns of native species distributions and their causes differed from non-native species along an elevation gradient; and 2) investigate inter- and intra-annual understory vascular plant species variability along an elevation gradient to inform long-term monitoring of plant invasion dynamics in the Wallowa Mountains. We sampled understory vascular plant communities in summer 2012 along three forest roads in the Wallowa Mountains. Transects (n=20) were evenly stratified by elevation (60 meters) along each road. Indicator species analysis (ISA) was used to identify habitat tendencies for non-native species. Non-metric multidimensional scaling (NMS) related community composition to environmental and species trait factors. Predictors of non-native and native species abundance and richness were evaluated using Non-parametric multiplicative regression (NPMR). Canopy openness and elevation niche widths were modeled for all common species and evaluated for evidence of high elevation or closed canopy specialization. Non-native species richness decreased continuously with increasing elevation. In contrast, native species richness displayed a unimodal distribution with maximum richness at the mid-elevations. According to NMS and NPMR, elevation, canopy openness, and disturbance were the strongest correlates of non-native species abundance. Non-native species were concentrated in low elevation bunchgrass, roadside, and open forest habitats with high canopy openness, and moderate to high disturbance intensity. Overlays of species trait factors onto ordinations revealed that the transition into the subalpine community and over-story canopy closure exceeding approximately 60 percent were potential barriers to non-native species establishment. Vegetation sampling was repeated three times (June, July, and August 2013) during the growing season in summer 2013 for a subset (n=10) of our transects. Blocked Multi Response Permutation Procedure (MRBP) was used to test the hypothesis of no change in species composition between years (summer 2012 and summer 2013) and between each sampling period (June, July, and August) within one growing season. NMS related community composition at different times to environmental and trait category factors. Blocked Indicator Species Analysis was used to identify species with tendencies towards specific sampling periods. Important predictors of vegetation change were identified and indicator species distributions were related to NMS axes using NPMR. Vegetation composition changed both between years and between each sampling period within one growing season. Species richness increased with sampling effort, dominant species were consistently found throughout all sampling periods and rare species showed the highest rate of turnover between sampling periods. The highest species richness and greatest number of indicator species were associated with the early summer (June) sampling period. Approximately 25% of all non-native species showed tendencies towards a specific sampling period where greater than half favored the June sampling period within lowland bunchgrass communities. Annual species including the most dominant non-native species within the lowland and montane zones showed the highest inter- and intra-annual variability compared to other trait categories. Total species richness was positively related to turnover and was the most important predictor of relative abundance change between all sampling periods. Species turnover was highest in species rich montane plots; however, trait abundance and richness did not statistically differ in montane plots. These data suggest that elevation, canopy, openness, and disturbance are important factors structuring non-native plant distributions in the Wallowa Mountains. Our findings that non-native species tended to be concentrated in low elevation, early successional habitats coupled with a lack of high elevation or closed canopy specialization indicates that non-native plants that occurr at the highest elevations are likely generalist species that depend on disturbance (primarily open over-story canopy) for spread into higher elevation sites until they are eventually filtered out by harsh environmental conditions coincident with the subalpine transition zone. Collectively these results suggest that interactions between introduction pathways that favor human assisted dispersal into the low-elevations where ruderal species are favored and environmental filters (elevation, canopy openness, and disturbance) are the dominant factors structuring non-native plant distributions in the Wallowa Mountains. Our results also indicate that long-term monitoring of vegetation change in the Wallowa Mountains will be improved through periodic sampling during each growing season. Sampling once during the spring or early summer and then again coincident with peak biomass should improve estimates of species distributions and diversity patterns by capturing both vernal and late season species. Early season sampling may be particularly important for monitoring non-native plants in the Wallowa Mountains as most non-natives were concentrated in low elevation semiarid bunchgrass communities where spring and early summer specialization is common. Title: Non-native and native plant species distributions and variability along an elevation gradient in the Wallowa Mountains, Oregon Author: Averett, Joshua P. Invasion by non-native plants into natural areas is an important component of global change that threatens biodiversity and ecosystem structure and function. Mountains are currently among the least invaded ecosystems, however, these biodiversity hotspots are increasingly under threat of exotic plant invasion. Evaluation of plant species distribution patterns in mountain ecosystems can provide insight into dominant processes of plant invasion and inform management to reduce the spread of non-native plants in mountains. The objectives of this study were to: 1) evaluate the main drivers of plant invasions in the Wallowa Mountain Range of northeastern Oregon, and the extent patterns of native species distributions and their causes differed from non-native species along an elevation gradient; and 2) investigate inter- and intra-annual understory vascular plant species variability along an elevation gradient to inform long-term monitoring of plant invasion dynamics in the Wallowa Mountains. We sampled understory vascular plant communities in summer 2012 along three forest roads in the Wallowa Mountains. Transects (n=20) were evenly stratified by elevation (60 meters) along each road. Indicator species analysis (ISA) was used to identify habitat tendencies for non-native species. Non-metric multidimensional scaling (NMS) related community composition to environmental and species trait factors. Predictors of non-native and native species abundance and richness were evaluated using Non-parametric multiplicative regression (NPMR). Canopy openness and elevation niche widths were modeled for all common species and evaluated for evidence of high elevation or closed canopy specialization. Non-native species richness decreased continuously with increasing elevation. In contrast, native species richness displayed a unimodal distribution with maximum richness at the mid-elevations. According to NMS and NPMR, elevation, canopy openness, and disturbance were the strongest correlates of non-native species abundance. Non-native species were concentrated in low elevation bunchgrass, roadside, and open forest habitats with high canopy openness, and moderate to high disturbance intensity. Overlays of species trait factors onto ordinations revealed that the transition into the subalpine community and over-story canopy closure exceeding approximately 60 percent were potential barriers to non-native species establishment. Vegetation sampling was repeated three times (June, July, and August 2013) during the growing season in summer 2013 for a subset (n=10) of our transects. Blocked Multi Response Permutation Procedure (MRBP) was used to test the hypothesis of no change in species composition between years (summer 2012 and summer 2013) and between each sampling period (June, July, and August) within one growing season. NMS related community composition at different times to environmental and trait category factors. Blocked Indicator Species Analysis was used to identify species with tendencies towards specific sampling periods. Important predictors of vegetation change were identified and indicator species distributions were related to NMS axes using NPMR. Vegetation composition changed both between years and between each sampling period within one growing season. Species richness increased with sampling effort, dominant species were consistently found throughout all sampling periods and rare species showed the highest rate of turnover between sampling periods. The highest species richness and greatest number of indicator species were associated with the early summer (June) sampling period. Approximately 25% of all non-native species showed tendencies towards a specific sampling period where greater than half favored the June sampling period within lowland bunchgrass communities. Annual species including the most dominant non-native species within the lowland and montane zones showed the highest inter- and intra-annual variability compared to other trait categories. Total species richness was positively related to turnover and was the most important predictor of relative abundance change between all sampling periods. Species turnover was highest in species rich montane plots; however, trait abundance and richness did not statistically differ in montane plots. These data suggest that elevation, canopy, openness, and disturbance are important factors structuring non-native plant distributions in the Wallowa Mountains. Our findings that non-native species tended to be concentrated in low elevation, early successional habitats coupled with a lack of high elevation or closed canopy specialization indicates that non-native plants that occurr at the highest elevations are likely generalist species that depend on disturbance (primarily open over-story canopy) for spread into higher elevation sites until they are eventually filtered out by harsh environmental conditions coincident with the subalpine transition zone. Collectively these results suggest that interactions between introduction pathways that favor human assisted dispersal into the low-elevations where ruderal species are favored and environmental filters (elevation, canopy openness, and disturbance) are the dominant factors structuring non-native plant distributions in the Wallowa Mountains. Our results also indicate that long-term monitoring of vegetation change in the Wallowa Mountains will be improved through periodic sampling during each growing season. Sampling once during the spring or early summer and then again coincident with peak biomass should improve estimates of species distributions and diversity patterns by capturing both vernal and late season species. Early season sampling may be particularly important for monitoring non-native plants in the Wallowa Mountains as most non-natives were concentrated in low elevation semiarid bunchgrass communities where spring and early summer specialization is common. Close

• 246. [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

• 247. [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

• 248. [Article] Prey Patch Patterns Predict Habitat Use by Top Marine Predators with Diverse Foraging Strategies

  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 Public ...

  Citation × Citation Citation Abstract Copy Title: Prey Patch Patterns Predict Habitat Use by Top Marine Predators with Diverse Foraging Strategies Author: Paredes, Rosana, Kuletz, Kathy J., Waluk, Chad M., Suryan, Robert M., Irons, David, Battaile, Brian C., Nordstrom, Chad A., Jones, Nathan, Trites, Andrew W., Benoit-Bird, Kelly J., Heppell, Scott A., Hoover, Brian 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 Public Library of Science and can be found at: http://www.plosone.org/home.action. Title: Prey Patch Patterns Predict Habitat Use by Top Marine Predators with Diverse Foraging Strategies Author: Paredes, Rosana, Kuletz, Kathy J., Waluk, Chad M., Suryan, Robert M., Irons, David, Battaile, Brian C., Nordstrom, Chad A., Jones, Nathan, Trites, Andrew W., Benoit-Bird, Kelly J., Heppell, Scott A., Hoover, Brian 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 Public Library of Science and can be found at: http://www.plosone.org/home.action. Close

• 249. [Article] Quantifying dilution and amplification in a community of hosts for tick-borne pathogens

  Data associated with this paper have been deposited in the KNB Data Repository: https://knb.ecoinformatics.org/#view/ knb.779.2

  Citation × Citation Citation Abstract Copy Title: Quantifying dilution and amplification in a community of hosts for tick-borne pathogens Author: Ostfeld, Richard S., Keesing, Felicia, Holt, Robert D., Levi, Taal, Barfield, Michael Data associated with this paper have been deposited in the KNB Data Repository: https://knb.ecoinformatics.org/#view/ knb.779.2 Title: Quantifying dilution and amplification in a community of hosts for tick-borne pathogens Author: Ostfeld, Richard S., Keesing, Felicia, Holt, Robert D., Levi, Taal, Barfield, Michael Data associated with this paper have been deposited in the KNB Data Repository: https://knb.ecoinformatics.org/#view/ knb.779.2 Close

• 250. [Article] Interactive visual analysis promotes exploration of long-term ecological data

  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 author(s) ...

  Citation × Citation Citation Abstract Copy Title: Interactive visual analysis promotes exploration of long-term ecological data Author: Swanson, Frederick, Pham, Tuan, Metoyer, Ronald, Pabst, Robert, Jones, Julia 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 author(s) and published by the Ecological Society of America. The published article can be found at: http://www.esajournals.org/loi/ecsp. Title: Interactive visual analysis promotes exploration of long-term ecological data Author: Swanson, Frederick, Pham, Tuan, Metoyer, Ronald, Pabst, Robert, Jones, Julia 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 author(s) and published by the Ecological Society of America. The published article can be found at: http://www.esajournals.org/loi/ecsp. Close