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• 21. [Article] TNC_ASPEN_SEC 1.pdf

  Citation × Citation Citation Abstract Copy Title: TNC_ASPEN_SEC 1.pdf Author: Ediger, Vernita, Seager, S Trent, Davis, Emily Jane Title: TNC_ASPEN_SEC 1.pdf Author: Ediger, Vernita, Seager, S Trent, Davis, Emily Jane Close

• 22. [Article] TNC_ASPEN_SEC 2.pdf

  Citation × Citation Citation Abstract Copy Title: TNC_ASPEN_SEC 2.pdf Author: Ediger, Vernita, Seager, S Trent, Davis, Emily Jane Title: TNC_ASPEN_SEC 2.pdf Author: Ediger, Vernita, Seager, S Trent, Davis, Emily Jane Close

• 23. [Article] TNC_ASPEN_SEC 3.pdf

  Citation × Citation Citation Abstract Copy Title: TNC_ASPEN_SEC 3.pdf Author: Ediger, Vernita, Seager, S Trent, Davis, Emily Jane Title: TNC_ASPEN_SEC 3.pdf Author: Ediger, Vernita, Seager, S Trent, Davis, Emily Jane Close

• 24. [Article] TNC_ASPEN_SEC 4.pdf

  Citation × Citation Citation Abstract Copy Title: TNC_ASPEN_SEC 4.pdf Author: Ediger, Vernita, Seager, S Trent, Davis, Emily Jane Title: TNC_ASPEN_SEC 4.pdf Author: Ediger, Vernita, Seager, S Trent, Davis, Emily Jane Close

• 25. [Article] TNC_ASPEN_SEC 5.pdf

  Citation × Citation Citation Abstract Copy Title: TNC_ASPEN_SEC 5.pdf Author: Ediger, Vernita, Seager, S Trent, Davis, Emily Jane Title: TNC_ASPEN_SEC 5.pdf Author: Ediger, Vernita, Seager, S Trent, Davis, Emily Jane Close

• 26. [Article] TNC_ASPEN_FULL DOC_FINAL for web.pdf

  Citation × Citation Citation Abstract Copy Title: TNC_ASPEN_FULL DOC_FINAL for web.pdf Author: Ediger, Vernita, Seager, S Trent, Davis, Emily Jane Title: TNC_ASPEN_FULL DOC_FINAL for web.pdf Author: Ediger, Vernita, Seager, S Trent, Davis, Emily Jane Close

• 27. [Article] Distributional patterns of 0-group Pacific cod (Gadus macrocephalus) in the eastern Bering Sea under variable recruitment and thermal conditions

  Despite the importance of Pacific cod in Bering Sea fisheries and foodwebs, little is known about the habitat use and the distribution of early life stages. We analysed 6 years of catch data for 0-group ...

  Citation × Citation Citation Abstract Copy Title: Distributional patterns of 0-group Pacific cod (Gadus macrocephalus) in the eastern Bering Sea under variable recruitment and thermal conditions Author: Miller, Jessica A., Hurst, Thomas P., Moss, Jamal H. Despite the importance of Pacific cod in Bering Sea fisheries and foodwebs, little is known about the habitat use and the distribution of early life stages. We analysed 6 years of catch data for 0-group Pacific cod in fishery-independent surveys of the Bering Sea shelf. Juvenile cod were most commonly captured on the middle shelf over depths of 50–80 m and were rarely captured north of 58°N. Consistently high catches were observed east of the Pribilof Islands and north of Port Moller along the Alaska Peninsula. There was evidence of density-dependent habitat selection at the local scale as the frequency of occurrence increased with regional catch per unit effort. At the basin scale, the southerly distribution of the weak 2009 cohort suggested the possibility of a range contraction for small cohorts. There was no consistent shift in the distribution of juvenile Pacific cod in response to interannual climate variability. These results for Pacific cod contrast with those observed for walleye pollock, which appears to exhibit greater variance in distribution, but are similar to patterns observed for juvenile Atlantic cod. Future work should focus on distribution in nearshore habitats and examine the patterns of dispersal and the connectivity of the Bering Sea and Gulf of Alaska populations. Title: Distributional patterns of 0-group Pacific cod (Gadus macrocephalus) in the eastern Bering Sea under variable recruitment and thermal conditions Author: Miller, Jessica A., Hurst, Thomas P., Moss, Jamal H. Despite the importance of Pacific cod in Bering Sea fisheries and foodwebs, little is known about the habitat use and the distribution of early life stages. We analysed 6 years of catch data for 0-group Pacific cod in fishery-independent surveys of the Bering Sea shelf. Juvenile cod were most commonly captured on the middle shelf over depths of 50–80 m and were rarely captured north of 58°N. Consistently high catches were observed east of the Pribilof Islands and north of Port Moller along the Alaska Peninsula. There was evidence of density-dependent habitat selection at the local scale as the frequency of occurrence increased with regional catch per unit effort. At the basin scale, the southerly distribution of the weak 2009 cohort suggested the possibility of a range contraction for small cohorts. There was no consistent shift in the distribution of juvenile Pacific cod in response to interannual climate variability. These results for Pacific cod contrast with those observed for walleye pollock, which appears to exhibit greater variance in distribution, but are similar to patterns observed for juvenile Atlantic cod. Future work should focus on distribution in nearshore habitats and examine the patterns of dispersal and the connectivity of the Bering Sea and Gulf of Alaska populations. Close

• 28. [Article] Short-tailed weasel space use in managed forests of western Oregon

  Although short-tailed weasels (Mustela erminea) are important predators of small mammals, little is known about their space use, habitat selection, or vulnerability to predation in North America. To evaluate ...

  Citation × Citation Citation Abstract Copy Title: Short-tailed weasel space use in managed forests of western Oregon Author: Linnell, Mark A Although short-tailed weasels (Mustela erminea) are important predators of small mammals, little is known about their space use, habitat selection, or vulnerability to predation in North America. To evaluate the effects of forest management and social structure on home range size and habitat selection of short-tailed weasels, I conducted a telemetry study in the Coast Ranges of western Oregon, USA. I used fixed kernel utilization distributions, multiple linear regression, and weighted compositional analysis to assess factors associated with home range size and habitat selection for 25 radio-marked short-tailed weasels. The radio-collared weasels selected early seral forest (5-15 years post-harvest) over closed canopy forest (>16 years postharvest). Females showed the strongest selection for early seral forest and had smaller home ranges than males (♀♀ x̄ = 10.4 hectares, 95% CI = 6.6-14.1 ha; ♂♂ x̄ = 53.3 hectares, 95% CI = 30.4-76.2 ha). Based on these observations, I proposed that weasels in my study exhibited a competitive hierarchy whereby the best exploitation competitors (females) selected the most productive cover types (early seral, fields) and appeared to be unaffected by interference competition from the larger males. Additionally, while radio-tracking weasels, I observed several mortalities, most of which I attributed to owls (4 out of 5 confirmed mortalities). Using Kaplan- Meier analysis, I estimated the estimated survival rate for the 9 month period of my study (June 2012-March 2013) was 0.36; 95% CI = 0.13-0.6. This estimate indicated an annual survival rate that was similar to the mean for 6 studies elsewhere in temperate North America in which the fate of weasels (Mustela spp.) was tracked (x̄ = 0.31 ± 0.09). I concluded that predation was an important factor limiting short-tailed weasel populations. Furthermore, strong selection for early seral cover, an ephemeral cover type, indicated that habitat for weasels in my study area may be limited to relatively short time periods. This may be due to forest management practices, including high density re-planting of conifers to accelerate the re-establishment of conifer trees after timber harvest. I suggest that reducing tree planting densities would favor weasel occupancy of managed forest by increasing the duration in which early seral vegetation is available. Title: Short-tailed weasel space use in managed forests of western Oregon Author: Linnell, Mark A Although short-tailed weasels (Mustela erminea) are important predators of small mammals, little is known about their space use, habitat selection, or vulnerability to predation in North America. To evaluate the effects of forest management and social structure on home range size and habitat selection of short-tailed weasels, I conducted a telemetry study in the Coast Ranges of western Oregon, USA. I used fixed kernel utilization distributions, multiple linear regression, and weighted compositional analysis to assess factors associated with home range size and habitat selection for 25 radio-marked short-tailed weasels. The radio-collared weasels selected early seral forest (5-15 years post-harvest) over closed canopy forest (>16 years postharvest). Females showed the strongest selection for early seral forest and had smaller home ranges than males (♀♀ x̄ = 10.4 hectares, 95% CI = 6.6-14.1 ha; ♂♂ x̄ = 53.3 hectares, 95% CI = 30.4-76.2 ha). Based on these observations, I proposed that weasels in my study exhibited a competitive hierarchy whereby the best exploitation competitors (females) selected the most productive cover types (early seral, fields) and appeared to be unaffected by interference competition from the larger males. Additionally, while radio-tracking weasels, I observed several mortalities, most of which I attributed to owls (4 out of 5 confirmed mortalities). Using Kaplan- Meier analysis, I estimated the estimated survival rate for the 9 month period of my study (June 2012-March 2013) was 0.36; 95% CI = 0.13-0.6. This estimate indicated an annual survival rate that was similar to the mean for 6 studies elsewhere in temperate North America in which the fate of weasels (Mustela spp.) was tracked (x̄ = 0.31 ± 0.09). I concluded that predation was an important factor limiting short-tailed weasel populations. Furthermore, strong selection for early seral cover, an ephemeral cover type, indicated that habitat for weasels in my study area may be limited to relatively short time periods. This may be due to forest management practices, including high density re-planting of conifers to accelerate the re-establishment of conifer trees after timber harvest. I suggest that reducing tree planting densities would favor weasel occupancy of managed forest by increasing the duration in which early seral vegetation is available. Close

• 29. [Article] Identifying habitat factors for canary rockfish (Sebastes pinniger) off Washington and Oregon using environmental data and trawl logbooks

  If fisheries managers are to effectively manage commercially exploited fish populations, a basic understanding of the factors that influence fish distribution and abundance is required. In 2005, efforts ...

  Citation × Citation Citation Abstract Copy Title: Identifying habitat factors for canary rockfish (Sebastes pinniger) off Washington and Oregon using environmental data and trawl logbooks Author: Vestfals, Cathleen D. If fisheries managers are to effectively manage commercially exploited fish populations, a basic understanding of the factors that influence fish distribution and abundance is required. In 2005, efforts to identify Essential Fish Habitat (EFH) for the 82 groundfish species managed by the Pacific Fishery Management Council along the West Coast resulted in the entire continental margin being designated as EFH. Clearly, our knowledge of EFH needs to be refined, which can be accomplished by gaining insight into how environmental variables shape the distribution of managed species. Habitat is commonly used to describe a set of environmental variables that are thought to influence occupancy. The aim of this thesis research is to detect and analyze the quantitative relationships between canary rockfish (Sebastes pinniger) presence/absence data, their spatial distribution, and various biotic and abiotic factors. The presence of canary rockfish at various locations was correlated against co-located environmental variables including bottom depths, temperatures, locations (latitude and longitude), seafloor substrate types, canary rockfish hotspots, and the presence/absence of other groundfish and invertebrate species. The statistical analysis was conducted using the generalized additive model (GAM), which is a nonparametric regression technique very well suited to model nonlinear speciesenvironment interactions. The GAM analysis was conducted using information collected from four different data sources. Data collected by the Alaska Fisheries Science Center (AFSC) from 1986 to 2001 provided information at distinct locations and times on the presence/absence of canary rockfish and other groundfish and invertebrate species, and associated depths and temperatures. Seafloor lithology maps for Oregon and Washington and 100-meter gridded bathymetric data, obtained from the Active Tectonics and Seafloor Mapping Lab at Oregon State University, provided information on the physical characteristics of the seafloor. These data were used in conjunction with the AFSC bottom trawl survey data to investigate the relationships between substrate type, slope and rugosity, and the presence of canary rockfish. Finally, locations of canary rockfish hotspots, or areas with high canary rockfish catch, were identified from Oregon commercial trawl logbook data (1995-2001) and provided information on distinct areas where the trawl fishing fleet had successfully caught canary rockfish in the past. Canary rockfish presence in trawl survey tows was associated with specific locations and ranges of bathymetry, temperatures, and substrate types, as well as proximity to canary rockfish hotspots, and particular fish and invertebrate communities. Survey year had a strong effect on the presence of canary rockfish, as did location (latitude and longitude) and depth. The geographic location of a survey tow had a negative effect on the presence of canary rockfish in the nearshore region, and a positive effect the further the location was from the coastline, with canary rockfish presence being highest off the Washington coast between 47.5°N and 48.5°N. While canary rockfish were found at depths between 57 m and 307 m in the survey, the majority of the tows with canary rockfish catch, over 90%, occurred between the depths of 57 m and 199 m. Though temperature did not have a significant effect on canary rockfish presence in the GAM, canary rockfish were associated with specific temperature ranges, only being caught at temperatures between 6.2°C and 9.0°C in the survey. Over 89% of the tows with canary rockfish catch occurred between 6.2°C and 7.9°C. Since temperature and bottom depth of the trawl survey tows were highly correlated, it was difficult to determine which variable was the causative factor in determining the probability of a canary rockfish being present. Canary rockfish presence was higher in survey tows made closer to canary rockfish hotspots, as well as hard bottom types. Finally, the presence of lingcod, yellowtail, silvergray, or redstripe rockfish in a survey tow increased the likelihood of canary rockfish being present, as did the presence of basketstars and corals. By studying the relationships between species and their environment, we can begin to understand the relative importance of how environmental variables shape the distribution of managed species. For ecosystem-based management strategies to be successful, the functional relationships between organisms and their habitat must be understood. The predictive model developed in this study can be used to identify areas off Oregon and Washington where canary rockfish are likely to be found in relation to various habitat factors, and can potentially be used to delineate areas that should be sampled in future surveys of canary rockfish. Additionally, this research will help to improve our understanding of the factors that influence canary rockfish distribution, which may produce a more realistic definition of canary rockfish habitat, and improve assessment. This study specifically focuses on canary rockfish, because this species currently constrains many West Coast fisheries for groundfish, however, the methods outlined here could be applied more generally to other species of interest. Title: Identifying habitat factors for canary rockfish (Sebastes pinniger) off Washington and Oregon using environmental data and trawl logbooks Author: Vestfals, Cathleen D. If fisheries managers are to effectively manage commercially exploited fish populations, a basic understanding of the factors that influence fish distribution and abundance is required. In 2005, efforts to identify Essential Fish Habitat (EFH) for the 82 groundfish species managed by the Pacific Fishery Management Council along the West Coast resulted in the entire continental margin being designated as EFH. Clearly, our knowledge of EFH needs to be refined, which can be accomplished by gaining insight into how environmental variables shape the distribution of managed species. Habitat is commonly used to describe a set of environmental variables that are thought to influence occupancy. The aim of this thesis research is to detect and analyze the quantitative relationships between canary rockfish (Sebastes pinniger) presence/absence data, their spatial distribution, and various biotic and abiotic factors. The presence of canary rockfish at various locations was correlated against co-located environmental variables including bottom depths, temperatures, locations (latitude and longitude), seafloor substrate types, canary rockfish hotspots, and the presence/absence of other groundfish and invertebrate species. The statistical analysis was conducted using the generalized additive model (GAM), which is a nonparametric regression technique very well suited to model nonlinear speciesenvironment interactions. The GAM analysis was conducted using information collected from four different data sources. Data collected by the Alaska Fisheries Science Center (AFSC) from 1986 to 2001 provided information at distinct locations and times on the presence/absence of canary rockfish and other groundfish and invertebrate species, and associated depths and temperatures. Seafloor lithology maps for Oregon and Washington and 100-meter gridded bathymetric data, obtained from the Active Tectonics and Seafloor Mapping Lab at Oregon State University, provided information on the physical characteristics of the seafloor. These data were used in conjunction with the AFSC bottom trawl survey data to investigate the relationships between substrate type, slope and rugosity, and the presence of canary rockfish. Finally, locations of canary rockfish hotspots, or areas with high canary rockfish catch, were identified from Oregon commercial trawl logbook data (1995-2001) and provided information on distinct areas where the trawl fishing fleet had successfully caught canary rockfish in the past. Canary rockfish presence in trawl survey tows was associated with specific locations and ranges of bathymetry, temperatures, and substrate types, as well as proximity to canary rockfish hotspots, and particular fish and invertebrate communities. Survey year had a strong effect on the presence of canary rockfish, as did location (latitude and longitude) and depth. The geographic location of a survey tow had a negative effect on the presence of canary rockfish in the nearshore region, and a positive effect the further the location was from the coastline, with canary rockfish presence being highest off the Washington coast between 47.5°N and 48.5°N. While canary rockfish were found at depths between 57 m and 307 m in the survey, the majority of the tows with canary rockfish catch, over 90%, occurred between the depths of 57 m and 199 m. Though temperature did not have a significant effect on canary rockfish presence in the GAM, canary rockfish were associated with specific temperature ranges, only being caught at temperatures between 6.2°C and 9.0°C in the survey. Over 89% of the tows with canary rockfish catch occurred between 6.2°C and 7.9°C. Since temperature and bottom depth of the trawl survey tows were highly correlated, it was difficult to determine which variable was the causative factor in determining the probability of a canary rockfish being present. Canary rockfish presence was higher in survey tows made closer to canary rockfish hotspots, as well as hard bottom types. Finally, the presence of lingcod, yellowtail, silvergray, or redstripe rockfish in a survey tow increased the likelihood of canary rockfish being present, as did the presence of basketstars and corals. By studying the relationships between species and their environment, we can begin to understand the relative importance of how environmental variables shape the distribution of managed species. For ecosystem-based management strategies to be successful, the functional relationships between organisms and their habitat must be understood. The predictive model developed in this study can be used to identify areas off Oregon and Washington where canary rockfish are likely to be found in relation to various habitat factors, and can potentially be used to delineate areas that should be sampled in future surveys of canary rockfish. Additionally, this research will help to improve our understanding of the factors that influence canary rockfish distribution, which may produce a more realistic definition of canary rockfish habitat, and improve assessment. This study specifically focuses on canary rockfish, because this species currently constrains many West Coast fisheries for groundfish, however, the methods outlined here could be applied more generally to other species of interest. Close

• 30. [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