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• 11. [Article] Young-of-the-year rockfish (Sebastes spp.) settlement dynamics in Oregon estuaries

  In the Pacific Northwest, several species of rockfishes (Sebastes spp.) are under extreme conservation measures due to low population levels. Although currently at healthy population levels, one species ...

  Citation × Citation Citation Abstract Copy Title: Young-of-the-year rockfish (Sebastes spp.) settlement dynamics in Oregon estuaries Author: Dauble, Alison D. In the Pacific Northwest, several species of rockfishes (Sebastes spp.) are under extreme conservation measures due to low population levels. Although currently at healthy population levels, one species of interest is the black rockfish (S. melanops), which has been shown to utilize estuarine habitat during its early life history stages. Black rockfish constitute a large portion of the recreational harvest in the Pacific Northwest, and are also a commercially fished species along the majority of the west coast. Annual recruitment in rockfishes has been shown to be extremely variable, and a better understanding of the factors behind successful recruitment and the subsequent settlement process would assist in prioritizing management and conservation efforts for this and other species. The overall goal of my study was to investigate the role that natural and anthropogenic influences play in the estuarine settlement dynamics of northeast Pacific rockfishes, using black rockfish as the primary study species. Genetic identifications confirmed that the majority of the young-of-the-year (YOY) rockfish captured during this study were S. melanops, with small numbers of S. caurinus and S. emphaeus present as well. Results from trapping surveys indicated that YOY black rockfish utilize multiple estuaries on the Oregon coast from spring through late fall, and may be present in highly developed estuaries through their first winter before moving to deeper habitats, as shown by late season increases in catch-per-unit-effort (CPUEs) and the capture of multiple age-1 juveniles in the estuary. Catches were higher in the more developed estuaries on the coast, suggesting that the presence of structure is an extremely important component to the settlement process in this species and that the continued development of Oregon estuaries may not adversely affect YOY rockfish settlement. Two years of dive surveys on a standardized set of artificial reef structures in Yaquina Bay showed that a settlement index of YOY rockfish within the estuary could reflect larger trends in the YOY population and suggest that habitat saturation is not a factor that affects the settlement process of YOY rockfish in estuaries. This study provides strong evidence of widespread use of estuarine habitat on the Oregon coast by black rockfish during their first year of life, and provides additional support that structure is an important component to the settlement process, and has set the groundwork for investigating inter-annual variation in the estuarine settlement of rockfish. Title: Young-of-the-year rockfish (Sebastes spp.) settlement dynamics in Oregon estuaries Author: Dauble, Alison D. In the Pacific Northwest, several species of rockfishes (Sebastes spp.) are under extreme conservation measures due to low population levels. Although currently at healthy population levels, one species of interest is the black rockfish (S. melanops), which has been shown to utilize estuarine habitat during its early life history stages. Black rockfish constitute a large portion of the recreational harvest in the Pacific Northwest, and are also a commercially fished species along the majority of the west coast. Annual recruitment in rockfishes has been shown to be extremely variable, and a better understanding of the factors behind successful recruitment and the subsequent settlement process would assist in prioritizing management and conservation efforts for this and other species. The overall goal of my study was to investigate the role that natural and anthropogenic influences play in the estuarine settlement dynamics of northeast Pacific rockfishes, using black rockfish as the primary study species. Genetic identifications confirmed that the majority of the young-of-the-year (YOY) rockfish captured during this study were S. melanops, with small numbers of S. caurinus and S. emphaeus present as well. Results from trapping surveys indicated that YOY black rockfish utilize multiple estuaries on the Oregon coast from spring through late fall, and may be present in highly developed estuaries through their first winter before moving to deeper habitats, as shown by late season increases in catch-per-unit-effort (CPUEs) and the capture of multiple age-1 juveniles in the estuary. Catches were higher in the more developed estuaries on the coast, suggesting that the presence of structure is an extremely important component to the settlement process in this species and that the continued development of Oregon estuaries may not adversely affect YOY rockfish settlement. Two years of dive surveys on a standardized set of artificial reef structures in Yaquina Bay showed that a settlement index of YOY rockfish within the estuary could reflect larger trends in the YOY population and suggest that habitat saturation is not a factor that affects the settlement process of YOY rockfish in estuaries. This study provides strong evidence of widespread use of estuarine habitat on the Oregon coast by black rockfish during their first year of life, and provides additional support that structure is an important component to the settlement process, and has set the groundwork for investigating inter-annual variation in the estuarine settlement of rockfish. Close

• 12. [Article] Twenty-year changes in riparian bird communities of east-central Oregon

  Over the last 50 years, riparian zones in the semi-arid West have gained recognition as disproportionately important habitats for both breeding bird communities and agricultural operations. Despite growing ...

  Citation × Citation Citation Abstract Copy Title: Twenty-year changes in riparian bird communities of east-central Oregon Author: Ellis, Michael S. Over the last 50 years, riparian zones in the semi-arid West have gained recognition as disproportionately important habitats for both breeding bird communities and agricultural operations. Despite growing interest in exploring avian-habitat relationships in these systems to better inform land management, few studies have attempted to describe temporal changes in the region's riparian bird communities. To provide a frame of reference for these changes, we compared indices of avian abundance and diversity from three streamside vegetation associations in east-central Oregon during the 2014 breeding season with baseline data collected by TA Sanders and WD Edge in 1993 and 1994 (Sanders and Edge 1998). Our objectives were to identify patterns of change in the avian community with a focus on riparian shrub-dependent species, to re-examine previously reported relationships between avian abundance and vegetation volume, and to identify possible causes of declines in abundance and diversity with the goal of providing land managers in the semi-arid region information to be used in the guidance and adaptation of management practices. We combined field protocols used by Sanders and Edge to survey birds along point count transects and to measure riparian vegetation with modern analytical techniques. We found few major differences in overall diversity between study periods, but documented precipitous declines in detections for two of three riparian shrub-dependent focal species - Yellow Warbler (Setophaga petechia) and Willow Flycatcher (Empidonax trailii). Song Sparrow (Melospiza melodia) detections declined by a smaller margin. Changes in number of detections for these species did not reflect trends in mesic shrub volume, which had been identified as a likely driver of obligate species abundance by Sanders and Edge but remained relatively unchanged between study periods. Declines of all three focal species reflected regional Breeding Bird Survey trends, corroborating our finding that their declines may not be a result of changes in local site conditions. Compositional similarity between avian communities was significantly higher in 2014 than in 1993-1994, exhibiting a shift toward greater homogenization between structurally distinct riparian habitats. Our results suggest managing working lands for riparian shrub cover or volume, an important metric of grazing intensity and riparian system health, may not be enough to conserve diversity and abundance of riparian-shrub dependent birds, and more work should be done to identify and alleviate factors contributing to these species' declines. Title: Twenty-year changes in riparian bird communities of east-central Oregon Author: Ellis, Michael S. Over the last 50 years, riparian zones in the semi-arid West have gained recognition as disproportionately important habitats for both breeding bird communities and agricultural operations. Despite growing interest in exploring avian-habitat relationships in these systems to better inform land management, few studies have attempted to describe temporal changes in the region's riparian bird communities. To provide a frame of reference for these changes, we compared indices of avian abundance and diversity from three streamside vegetation associations in east-central Oregon during the 2014 breeding season with baseline data collected by TA Sanders and WD Edge in 1993 and 1994 (Sanders and Edge 1998). Our objectives were to identify patterns of change in the avian community with a focus on riparian shrub-dependent species, to re-examine previously reported relationships between avian abundance and vegetation volume, and to identify possible causes of declines in abundance and diversity with the goal of providing land managers in the semi-arid region information to be used in the guidance and adaptation of management practices. We combined field protocols used by Sanders and Edge to survey birds along point count transects and to measure riparian vegetation with modern analytical techniques. We found few major differences in overall diversity between study periods, but documented precipitous declines in detections for two of three riparian shrub-dependent focal species - Yellow Warbler (Setophaga petechia) and Willow Flycatcher (Empidonax trailii). Song Sparrow (Melospiza melodia) detections declined by a smaller margin. Changes in number of detections for these species did not reflect trends in mesic shrub volume, which had been identified as a likely driver of obligate species abundance by Sanders and Edge but remained relatively unchanged between study periods. Declines of all three focal species reflected regional Breeding Bird Survey trends, corroborating our finding that their declines may not be a result of changes in local site conditions. Compositional similarity between avian communities was significantly higher in 2014 than in 1993-1994, exhibiting a shift toward greater homogenization between structurally distinct riparian habitats. Our results suggest managing working lands for riparian shrub cover or volume, an important metric of grazing intensity and riparian system health, may not be enough to conserve diversity and abundance of riparian-shrub dependent birds, and more work should be done to identify and alleviate factors contributing to these species' declines. Close

• 13. [Article] Comparative hazard assessment for protected species in a fire-prone landscape

  This is the author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/forest-ecology-...

  Citation × Citation Citation Abstract Copy Title: Comparative hazard assessment for protected species in a fire-prone landscape Author: Mealey, Stephen P., Roloff, Gary J., Bailey, John D. This is the author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/forest-ecology-and-management/. Title: Comparative hazard assessment for protected species in a fire-prone landscape Author: Mealey, Stephen P., Roloff, Gary J., Bailey, John D. This is the author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/forest-ecology-and-management/. Close

• 14. [Article] Utilizing hunter harvest effort to survey for wildlife disease: A case study of West Nile virus in greater sage‐grouse

  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 Wildlife Society ...

  Citation × Citation Citation Abstract Copy Title: Utilizing hunter harvest effort to survey for wildlife disease: A case study of West Nile virus in greater sage‐grouse Author: Hofmeister, Erik K., Dusek, Robert J., Franson, J. Christian, Hagen, Christian A., Budeau, David 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 Wildlife Society and published by John Wiley & Sons, Ltd. It can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%291938-5463a Title: Utilizing hunter harvest effort to survey for wildlife disease: A case study of West Nile virus in greater sage‐grouse Author: Hofmeister, Erik K., Dusek, Robert J., Franson, J. Christian, Hagen, Christian A., Budeau, David 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 Wildlife Society and published by John Wiley & Sons, Ltd. It can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%291938-5463a Close

• 15. [Article] Annual reversible plasticity of feeding structures: cyclical changes of jaw allometry in a sea urchin

  This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the Royal Society and can be found at: http://rspb.royalsocietypublishing.org/....

  Citation × Citation Citation Abstract Copy Title: Annual reversible plasticity of feeding structures: cyclical changes of jaw allometry in a sea urchin Author: Hernández, José Carlos, Clemente, Sabrina, Ebert, Thomas A. This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the Royal Society and can be found at: http://rspb.royalsocietypublishing.org/. Title: Annual reversible plasticity of feeding structures: cyclical changes of jaw allometry in a sea urchin Author: Hernández, José Carlos, Clemente, Sabrina, Ebert, Thomas A. This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the Royal Society and can be found at: http://rspb.royalsocietypublishing.org/. Close

• 16. [Article] Carbon isotopes show snowpack acts as a valuable moisture subsidy to mountain forests in the Oregon Cascades

  This study examines climatological influences, particularly that of snowpack, on tree growth and stable carbon isotope discrimination (Δ¹³C) from ~1980 to 2013 at two sites located in the upper reaches ...

  Citation × Citation Citation Abstract Copy Title: Carbon isotopes show snowpack acts as a valuable moisture subsidy to mountain forests in the Oregon Cascades Author: Ratcliff, Christopher J. This study examines climatological influences, particularly that of snowpack, on tree growth and stable carbon isotope discrimination (Δ¹³C) from ~1980 to 2013 at two sites located in the upper reaches of the McKenzie River watershed of the Oregon Cascade Mountains. We tested the use of Δ¹³C values from latewood, corroborated by tree-ring width chronologies as precipitation proxies to develop correlations between moisture stress and climate variables. Tree species at each site included Douglas-fir and mountain hemlock. Interpolated meteorological and snowpack data included snow water equivalent (SWE), precipitation, atmospheric temperature, vapor pressure deficit (VPD), relative humidity (RH), and a metric estimating growing season length. Significant correlations between latewood Δ¹³C and winter SWE at each site indicated the importance of winter snowpack to our selected tree species (r = 0.35, r = 0.43). Late summer precipitation and relative humidity (RH) were also significantly correlated with Δ¹³C (r = 0.49, r = 0.46; r = 0.43, r = 0.44). High correlations at both sites reinforced that late summer VPD was the primary driver of Δ¹³C (r = - 0.67, r = -0.61), which is often associated with moisture stress. This was further supported by correlations between air temperature and Δ¹³C (r = -0.46, r = -0.47), which drives much of the variation in VPD. Growing season length also showed significance in mountain hemlocks at the site with longer average snowpack (r = -0.22, r = -0.44). Moisture supplied by spring snow melt is a seasonably limited resource, nonetheless both sites clearly showed that snowpack acts as a valuable moisture subsidy to coniferous mountain forests in the Oregon Cascades. This study acts as a useful case study for future investigations into the relationship between snowpack and forest health in the Pacific North West. Title: Carbon isotopes show snowpack acts as a valuable moisture subsidy to mountain forests in the Oregon Cascades Author: Ratcliff, Christopher J. This study examines climatological influences, particularly that of snowpack, on tree growth and stable carbon isotope discrimination (Δ¹³C) from ~1980 to 2013 at two sites located in the upper reaches of the McKenzie River watershed of the Oregon Cascade Mountains. We tested the use of Δ¹³C values from latewood, corroborated by tree-ring width chronologies as precipitation proxies to develop correlations between moisture stress and climate variables. Tree species at each site included Douglas-fir and mountain hemlock. Interpolated meteorological and snowpack data included snow water equivalent (SWE), precipitation, atmospheric temperature, vapor pressure deficit (VPD), relative humidity (RH), and a metric estimating growing season length. Significant correlations between latewood Δ¹³C and winter SWE at each site indicated the importance of winter snowpack to our selected tree species (r = 0.35, r = 0.43). Late summer precipitation and relative humidity (RH) were also significantly correlated with Δ¹³C (r = 0.49, r = 0.46; r = 0.43, r = 0.44). High correlations at both sites reinforced that late summer VPD was the primary driver of Δ¹³C (r = - 0.67, r = -0.61), which is often associated with moisture stress. This was further supported by correlations between air temperature and Δ¹³C (r = -0.46, r = -0.47), which drives much of the variation in VPD. Growing season length also showed significance in mountain hemlocks at the site with longer average snowpack (r = -0.22, r = -0.44). Moisture supplied by spring snow melt is a seasonably limited resource, nonetheless both sites clearly showed that snowpack acts as a valuable moisture subsidy to coniferous mountain forests in the Oregon Cascades. This study acts as a useful case study for future investigations into the relationship between snowpack and forest health in the Pacific North West. Close

• 17. [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

• 18. [Article] A new model to simulate climate-change impacts on forest succession for local land management

  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 Ecological ...

  Citation × Citation Citation Abstract Copy Title: A new model to simulate climate-change impacts on forest succession for local land management Author: Bolte, John P., Bridgham, Scott D., Neilson, Ronald P., et al., Yospin, Gabriel I. 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 Ecological Society of America and can be found at: http://www.esajournals.org/loi/ecap. Title: A new model to simulate climate-change impacts on forest succession for local land management Author: Bolte, John P., Bridgham, Scott D., Neilson, Ronald P., et al., Yospin, Gabriel I. 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 Ecological Society of America and can be found at: http://www.esajournals.org/loi/ecap. Close

• 19. [Article] Examining ectomycorrhizal communities of ponderosa pine and lodgepole pine in the south-central Oregon pumice zone

  Background information is presented that provides historical perspectives on the field of mycology in the Pacific Northwest and its role in forest management. The series of events and decisions that have ...

  Citation × Citation Citation Abstract Copy Title: Examining ectomycorrhizal communities of ponderosa pine and lodgepole pine in the south-central Oregon pumice zone Author: Garcia, Maria Osuna Background information is presented that provides historical perspectives on the field of mycology in the Pacific Northwest and its role in forest management. The series of events and decisions that have led to previous studies (or lack of studies) in the field also dictate the directions of current research. Culture, philosophy, and history all play a role in the questions that may be asked today. Examining the past gives light to the questions that are asked in the present and future. Forest ecosystems of the Pacific Northwest are changing as a result of climate change. Rise of global temperatures, decline of winter precipitation, earlier loss of snowpack, and increased summer drought are altering the range of Pinus contorta. As environmental conditions change, Pinus ponderosa may establish within the historic Pinus contorta range. Successful pine species migration will be constrained by the distribution or co-migration of ectomycorrhizal fungi (EMF). Knowledge of the linkages among soil fungal diversity, community structure, and environmental factors is critical to understanding the organization and stability of pine ecosystems. The objectives of this study are to establish an informational foundation of the EMF communities of P. ponderosa and P. contorta in the Deschutes National Forest and to examine soil characteristics associated with community composition. We examined EMF root tips of P. ponderosa and P. contorta in soil cores and conducted soil chemistry analysis for P. ponderosa. Results indicate that Cenococcum geophilum, Rhizopogon salebrosus, and Inocybe flocculosa are dominant in both P. contorta and P. ponderosa soil cores. Rhizopogon spp. were ubiquitous in P. ponderosa. There was no significant difference between EMF communities of P. ponderosa and P. contorta at the species level. Ordination analysis suggests that pH, Bray-phosphorus, total phosphorus (P), carbon (C), mineralizable nitrogen (N), ammonium (NH₄) and nitrate (NO₃) are driving EMF community composition in P. ponderosa. We found a significant linear relationship between EMF species richness and mineralizable N. Title: Examining ectomycorrhizal communities of ponderosa pine and lodgepole pine in the south-central Oregon pumice zone Author: Garcia, Maria Osuna Background information is presented that provides historical perspectives on the field of mycology in the Pacific Northwest and its role in forest management. The series of events and decisions that have led to previous studies (or lack of studies) in the field also dictate the directions of current research. Culture, philosophy, and history all play a role in the questions that may be asked today. Examining the past gives light to the questions that are asked in the present and future. Forest ecosystems of the Pacific Northwest are changing as a result of climate change. Rise of global temperatures, decline of winter precipitation, earlier loss of snowpack, and increased summer drought are altering the range of Pinus contorta. As environmental conditions change, Pinus ponderosa may establish within the historic Pinus contorta range. Successful pine species migration will be constrained by the distribution or co-migration of ectomycorrhizal fungi (EMF). Knowledge of the linkages among soil fungal diversity, community structure, and environmental factors is critical to understanding the organization and stability of pine ecosystems. The objectives of this study are to establish an informational foundation of the EMF communities of P. ponderosa and P. contorta in the Deschutes National Forest and to examine soil characteristics associated with community composition. We examined EMF root tips of P. ponderosa and P. contorta in soil cores and conducted soil chemistry analysis for P. ponderosa. Results indicate that Cenococcum geophilum, Rhizopogon salebrosus, and Inocybe flocculosa are dominant in both P. contorta and P. ponderosa soil cores. Rhizopogon spp. were ubiquitous in P. ponderosa. There was no significant difference between EMF communities of P. ponderosa and P. contorta at the species level. Ordination analysis suggests that pH, Bray-phosphorus, total phosphorus (P), carbon (C), mineralizable nitrogen (N), ammonium (NH₄) and nitrate (NO₃) are driving EMF community composition in P. ponderosa. We found a significant linear relationship between EMF species richness and mineralizable N. Close

• 20. [Article] Variability in mesoscale circulation and its effects on zooplankton distribution in the Northern California Current

  In eastern boundary current upwelling ecosystems, mesoscale circulation features such as eddies and upwelling filaments play a prominent role in the transfer of water and the associated plankton from the ...

  Citation × Citation Citation Abstract Copy Title: Variability in mesoscale circulation and its effects on zooplankton distribution in the Northern California Current Author: Keister, Julie Eileen In eastern boundary current upwelling ecosystems, mesoscale circulation features such as eddies and upwelling filaments play a prominent role in the transfer of water and the associated plankton from the productive nearshore to the oligotrophic deep sea. The relationship between mesoscale circulation, zooplankton distributions, and the across-shelf transport of coastal taxa and biomass in the California Current System was studied using data collected as part of the U.S. Global Ocean Ecosystems Dynamics (GLOBEC) Northeast Pacific Program. Sea surface height from >13 years of satellite altimeter data was used to characterize the spatial and temporal variability in mesoscale circulation in the northern California Current (35°N-49°N) and explore mechanisms of variability. High spatial and temporal variation in mesoscale energy occurred. Energy was not strongly linked to upwelling winds, but did correspond to climate indices, indicating that basin-scale processes play a role in controlling the circulation. CTD casts, zooplankton net tows, and Acoustic Doppler Current Profiler (ADCP) velocities collected during a research cruise conducted in summer 2000 off Oregon and northern California were used to describe the effects of mesoscale circulation on distributions of zooplankton. During the cruise, a filament of the coastal upwelling jet extended seaward of Cape Blanco (42.8°N) resulting in the displacement of coastal zooplankton to >100 km off the continental shelf. Velocities and standing stocks of zooplankton were used to estimate seaward transport of 0.5 Sv in the upper 100 m of the filament, in which zooplankton biomass averaged ~20 mg carbon/m³. That offshore transport equated to >900 metric tons of carbon each day, and 4-5x10⁴ tons over the 6-8 week lifetime of the circulation feature. Although the flux represented a small portion (<2%) of the shelf zooplankton biomass, the transport resulted in an offshore "hot-spot" in which biomass was 3-4X higher than in the surrounding ocean. Distributions of early life history stages of euphausiids indicated that retention of coastal populations may be strongly affected by the offshore advection. Finally, satellite sea surface temperature (SST) and sampling conducted during five summers were used to explore variability in the relationship between mesoscale circulation features and distributions of zooplankton. Circulation patterns differed among cruises and were reflected in zooplankton distributions. Circulation features resulted in the occurrence of cold surface water and coastal taxa offshore, but species abundances and presence/absence of taxa at specific locations were not predictable from satellite SSTs. These results are relevant to studies of ecosystem dynamics and the global carbon cycle because mesoscale circulation plays an important role in the seaward transport of carbon, retention and loss of taxa from the continental shelf, and creation of offshore structure which may be exploited by upper trophic level organisms. Title: Variability in mesoscale circulation and its effects on zooplankton distribution in the Northern California Current Author: Keister, Julie Eileen In eastern boundary current upwelling ecosystems, mesoscale circulation features such as eddies and upwelling filaments play a prominent role in the transfer of water and the associated plankton from the productive nearshore to the oligotrophic deep sea. The relationship between mesoscale circulation, zooplankton distributions, and the across-shelf transport of coastal taxa and biomass in the California Current System was studied using data collected as part of the U.S. Global Ocean Ecosystems Dynamics (GLOBEC) Northeast Pacific Program. Sea surface height from >13 years of satellite altimeter data was used to characterize the spatial and temporal variability in mesoscale circulation in the northern California Current (35°N-49°N) and explore mechanisms of variability. High spatial and temporal variation in mesoscale energy occurred. Energy was not strongly linked to upwelling winds, but did correspond to climate indices, indicating that basin-scale processes play a role in controlling the circulation. CTD casts, zooplankton net tows, and Acoustic Doppler Current Profiler (ADCP) velocities collected during a research cruise conducted in summer 2000 off Oregon and northern California were used to describe the effects of mesoscale circulation on distributions of zooplankton. During the cruise, a filament of the coastal upwelling jet extended seaward of Cape Blanco (42.8°N) resulting in the displacement of coastal zooplankton to >100 km off the continental shelf. Velocities and standing stocks of zooplankton were used to estimate seaward transport of 0.5 Sv in the upper 100 m of the filament, in which zooplankton biomass averaged ~20 mg carbon/m³. That offshore transport equated to >900 metric tons of carbon each day, and 4-5x10⁴ tons over the 6-8 week lifetime of the circulation feature. Although the flux represented a small portion (<2%) of the shelf zooplankton biomass, the transport resulted in an offshore "hot-spot" in which biomass was 3-4X higher than in the surrounding ocean. Distributions of early life history stages of euphausiids indicated that retention of coastal populations may be strongly affected by the offshore advection. Finally, satellite sea surface temperature (SST) and sampling conducted during five summers were used to explore variability in the relationship between mesoscale circulation features and distributions of zooplankton. Circulation patterns differed among cruises and were reflected in zooplankton distributions. Circulation features resulted in the occurrence of cold surface water and coastal taxa offshore, but species abundances and presence/absence of taxa at specific locations were not predictable from satellite SSTs. These results are relevant to studies of ecosystem dynamics and the global carbon cycle because mesoscale circulation plays an important role in the seaward transport of carbon, retention and loss of taxa from the continental shelf, and creation of offshore structure which may be exploited by upper trophic level organisms. Close