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• 2771. [Article] Habitat use and movement behavior of Pacific marten (Martes caurina) in response to forest management practices in Lassen National Forest, California

  Some of the most pressing conservation concerns involve declining populations of species with low fecundity and highly specialized foraging and reproductive requirements. Yet, we often lack a functional ...

  Citation × Citation Citation Abstract Copy Title: Habitat use and movement behavior of Pacific marten (Martes caurina) in response to forest management practices in Lassen National Forest, California Author: Moriarty, Katie M. Some of the most pressing conservation concerns involve declining populations of species with low fecundity and highly specialized foraging and reproductive requirements. Yet, we often lack a functional understanding of how individuals of those species interact with their environment, specifically how their movement is affected by human-induced changes. In order to maintain connectivity and viable populations, public land managers require science to inform how changes in structure affect the individual movements and thus population connectivity of sensitive species. I collected detailed movement data on Pacific martens (Martes caurina) in Lassen National Forest, California, during 2010-2013. Martens are small carnivores that are closely associated with old forest elements (e.g., large snags and logs). Marten populations rapidly decline with loss and fragmentation of forest cover. As such, martens are a U.S. Forest Service Management Indicator Species and a Species of Special Concern in the state of California. My goal was to understand martens' behavior in forest patches that were altered by thinning to remove ladder fuels-small diameter trees, understory vegetation, and branches near the ground. Such fuels treatments are increasingly prevalent on public lands, especially in dry forests, to reduce risk of high-severity and high-intensity fire. Although previous research suggested martens selection for dense forest and avoid gaps in forest cover, no information was available describing martens' use of simplified thinned patches. The objectives of my dissertation were to: (1) test whether marten movement and activity could accurately be measured using miniature GPS collars, and (2) evaluate marten use, selection, and behavior in patches that differed in structural complexity. Global positioning system (GPS) telemetry provides opportunities to collect detailed information from free-ranging animals with a high degree of precision and accuracy. Miniature GPS collars (42-60g) have only been available since 2009 for mammals and have not been consistently effective. Furthermore, all GPS units suffer from non-random data loss and location error, which is often exacerbated by dense vegetation. Given these constraints, it was questionable whether GPS collars would be an effective tool for studying martens. In Chapter 1, I evaluated how satellite data and environmental conditions affected performance of GPS units. I used a paired experimental design and programmed the GPS unit to retain or remove satellite data before attempting a location (fix). I found that short intervals between fix attempts significantly increased the likelihood of fix success. Locations estimated using at least 4 satellites were, on average, within 28 m of the actual location regardless of vegetation cover. Thus, location estimates at short intervals with >4 satellites were not typically biased by dense vegetation. Accurate fine-scale information on martens was necessary to quantify and interpret patch use and habitat selection. I evaluated martens’ use and behavior in three forest patch types that differed in structural complexity (complex, simple, and open). In Chapter 2, I quantified use patch use in two seasons–summer and winter. I used food-titration experiments to standardize motivation of martens to enter different patch types and compared these short-term incentivized experiments with year-round observational telemetry data (GPS and very high frequency telemetry). Martens selected complex patches and avoided both simple patches and openings, but not equivalently–openings were strongly avoided. With baited incentive, martens were more likely to enter simple patches and openings during winter, when deep snow was present. Because marten patch use differed during winter, I concluded that researchers should use caution when using seasonally collected data to create year-round habitat models. Overall, movement was most limited during summer when predation risk likely deterred martens from moving through simple patches and openings. In Chapter 3, I quantified habitat selection and marten behavior using fine-scale movement data. I evaluated movement-based habitat selection at two scales: (1) selection of home ranges within landscapes and (2) selection of patches within the home ranges. I characterized marten movement patterns and tested whether variance, speed, and sinuosity of movements differed by patch, sex, and season. Martens selected home ranges with fewer openings than available in the landscape, and selected complex patches over simple patches and openings within their home range. On average, martens moved approximately 7 km per day and greater than 1 km per hour – which is notably high for a 600-1000g mammal. Martens moved more slowly, consistently, and sinuously in complex patches. In openings, martens traveled linearly with greater variance in their speed. In simple patches, movement generally was linear and rapid with some variation. I hypothesized that martens used complex patches for foraging and acquisition of resources, traveled through simple patches with the potential for infrequent foraging bouts, and very infrequently crossed openings. Although I found some differences in movement behavior between sexes and seasons, behavior was generally consistent for both sexes in different patch types. I provide general conclusions in Chapter 4 and discuss considerations for future research and management. Title: Habitat use and movement behavior of Pacific marten (Martes caurina) in response to forest management practices in Lassen National Forest, California Author: Moriarty, Katie M. Some of the most pressing conservation concerns involve declining populations of species with low fecundity and highly specialized foraging and reproductive requirements. Yet, we often lack a functional understanding of how individuals of those species interact with their environment, specifically how their movement is affected by human-induced changes. In order to maintain connectivity and viable populations, public land managers require science to inform how changes in structure affect the individual movements and thus population connectivity of sensitive species. I collected detailed movement data on Pacific martens (Martes caurina) in Lassen National Forest, California, during 2010-2013. Martens are small carnivores that are closely associated with old forest elements (e.g., large snags and logs). Marten populations rapidly decline with loss and fragmentation of forest cover. As such, martens are a U.S. Forest Service Management Indicator Species and a Species of Special Concern in the state of California. My goal was to understand martens' behavior in forest patches that were altered by thinning to remove ladder fuels-small diameter trees, understory vegetation, and branches near the ground. Such fuels treatments are increasingly prevalent on public lands, especially in dry forests, to reduce risk of high-severity and high-intensity fire. Although previous research suggested martens selection for dense forest and avoid gaps in forest cover, no information was available describing martens' use of simplified thinned patches. The objectives of my dissertation were to: (1) test whether marten movement and activity could accurately be measured using miniature GPS collars, and (2) evaluate marten use, selection, and behavior in patches that differed in structural complexity. Global positioning system (GPS) telemetry provides opportunities to collect detailed information from free-ranging animals with a high degree of precision and accuracy. Miniature GPS collars (42-60g) have only been available since 2009 for mammals and have not been consistently effective. Furthermore, all GPS units suffer from non-random data loss and location error, which is often exacerbated by dense vegetation. Given these constraints, it was questionable whether GPS collars would be an effective tool for studying martens. In Chapter 1, I evaluated how satellite data and environmental conditions affected performance of GPS units. I used a paired experimental design and programmed the GPS unit to retain or remove satellite data before attempting a location (fix). I found that short intervals between fix attempts significantly increased the likelihood of fix success. Locations estimated using at least 4 satellites were, on average, within 28 m of the actual location regardless of vegetation cover. Thus, location estimates at short intervals with >4 satellites were not typically biased by dense vegetation. Accurate fine-scale information on martens was necessary to quantify and interpret patch use and habitat selection. I evaluated martens’ use and behavior in three forest patch types that differed in structural complexity (complex, simple, and open). In Chapter 2, I quantified use patch use in two seasons–summer and winter. I used food-titration experiments to standardize motivation of martens to enter different patch types and compared these short-term incentivized experiments with year-round observational telemetry data (GPS and very high frequency telemetry). Martens selected complex patches and avoided both simple patches and openings, but not equivalently–openings were strongly avoided. With baited incentive, martens were more likely to enter simple patches and openings during winter, when deep snow was present. Because marten patch use differed during winter, I concluded that researchers should use caution when using seasonally collected data to create year-round habitat models. Overall, movement was most limited during summer when predation risk likely deterred martens from moving through simple patches and openings. In Chapter 3, I quantified habitat selection and marten behavior using fine-scale movement data. I evaluated movement-based habitat selection at two scales: (1) selection of home ranges within landscapes and (2) selection of patches within the home ranges. I characterized marten movement patterns and tested whether variance, speed, and sinuosity of movements differed by patch, sex, and season. Martens selected home ranges with fewer openings than available in the landscape, and selected complex patches over simple patches and openings within their home range. On average, martens moved approximately 7 km per day and greater than 1 km per hour – which is notably high for a 600-1000g mammal. Martens moved more slowly, consistently, and sinuously in complex patches. In openings, martens traveled linearly with greater variance in their speed. In simple patches, movement generally was linear and rapid with some variation. I hypothesized that martens used complex patches for foraging and acquisition of resources, traveled through simple patches with the potential for infrequent foraging bouts, and very infrequently crossed openings. Although I found some differences in movement behavior between sexes and seasons, behavior was generally consistent for both sexes in different patch types. I provide general conclusions in Chapter 4 and discuss considerations for future research and management. Close

• 2772. [Article] Impacts of earlier emerging steelhead fry of hatchery origin on the social structure, distribution, and growth of wild steelhead fry

  Newly emerged steelhead fry (Oncorhynchus mvkiss) of hatchery and wild origins were studied in laboratory stream channels and natural streams. Objectives of the study were to determine if and how earlier emerging ...

  Citation × Citation Citation Abstract Copy Title: Impacts of earlier emerging steelhead fry of hatchery origin on the social structure, distribution, and growth of wild steelhead fry Author: Noble, Sandra M. (Sandra Marie) Newly emerged steelhead fry (Oncorhynchus mvkiss) of hatchery and wild origins were studied in laboratory stream channels and natural streams. Objectives of the study were to determine if and how earlier emerging hatchery fry influence the emigration, realized densities, growth, habitat use, social structure, and activity patterns of localized populations of wild steelhead fry when the hatchery fry have a competitive advantage conferred by larger size and prior residence. During 1986 and 1987, the above variables were observed daily among hatchery and wild steelhead fry in laboratory stream channels for 8 weeks following emergence in June. The habitat use and social activities for fry of both origins were observed weekly in natural stream reaches from June through August in 1987 to corroborate lab findings. In lab channels, both hatchery and wild fry received 2 treatments: living alone (allopatry) and living together (sympatry). In the lab, fry of hatchery origin emerged 7 to 10 d prior to wild fry and remained larger in size during the 8 weeks of study both years. In natural stream reaches, fry of each origin were observed only in allopatric situations. Wild fry in the field emerged from natural redds while hatchery fry were released in stream reaches as unfed, newly emerged (swim-up) fry. Hatchery and wild fry in lab sections were found to be very similar in their emigration rates, distances to nearest neighbor, growth rates, and use of habitat. Both fry types, regardless of treatment or environment (lab or field), established similar stable social structure and used the same types of aggressive acts. Among all lab groups, once a fry became dominant, it retained that social status to the end of the study period. Significant differences (P<.05 both years) among comparison tests were: 1) in allopatric lab sections, wild fry maintained larger densities than hatchery fry, 2) in sympatry, hatchery fry had a greater tendency to establish stable focal points and social hierarchies more readily, defend larger areas, have better condition, prefer pools with overhead cover more frequently, be more aggressive, and reach stable densities more quickly than the wild fry, 3) fewer hatchery fry in sympatry maintained nomadic positions than wild fry in both treatments, 4) in sympatry, hatchery fry directed more acts of overt aggression toward wild fry than other hatchery fry, 5) wild fry in sympatry usually used defensive or less offensive acts of aggression when interacting with other fry, 6) fry of both origins in natural stream reaches maintained greater distances to their nearest neighbor than fry in allopatric lab sections, 7) dominant hatchery fry in both treatments maintained larger focal areas than subdominant fry, 8) hatchery fry maintained longer lengths than wild fry through the duration of the study, and 9) hatchery fry were more aggressive in sympatry than in allopatry. Potential differences (P<.05 in one year and P<.1 in the other year) were: 1) wild fry in sympatry had lower realized densities, maintained smaller focal areas, had greater proportions of nomadic individuals, and established stable social hierarchies slower than wild fry in allopatric lab sections, 2) wild fry in sympatry had poorer condition than all other fry groups in lab sections, 3) in sympatry, wild fry were the recipients of the majority of aggressive acts perpetrated by hatchery fry and other wild fry and usually assumed the subordinate positions within the social hierarchy, 4) all fry in the lab showed a high preference for pools with overhead cover and low preference for gravel and fines and run areas, and 5) wild fry in allopatric lab sections were more socially active than hatchery fry while the reverse was observed in the natural streams. Any influences that could be attributed to inherent differences between stock origins were probably masked by size differences between fry types. The study would have been more complete had I included sympatric lab sections where wild fry emerged first and where fry types emerged simultaneously, and sympatric reaches in natural streams. Results were further confounded by the limited number of wild adults used for broodstock in the lab segment of this study. Progeny produced from so few adults (5 adults of each sex each year) would have very limited genotypic variation compared to what occurs in natural streams. This may partially explain why some findings from lab sections and natural stream reaches differed. Likewise, genotypic expression among wild fry in lab sections may have varied greatly between years. This could explain differences found between years in behavior of wild fry in similar lab treatments. Although this study does not simulate all possible scenarios, results support suspicions that introductions of hatchery fry of larger size and earlier emergence into streams containing wild stocks could disrupt the social structure and negatively influence the realized densities, spatial distribution, growth, and behavior of wild juveniles in recipient streams. Title: Impacts of earlier emerging steelhead fry of hatchery origin on the social structure, distribution, and growth of wild steelhead fry Author: Noble, Sandra M. (Sandra Marie) Newly emerged steelhead fry (Oncorhynchus mvkiss) of hatchery and wild origins were studied in laboratory stream channels and natural streams. Objectives of the study were to determine if and how earlier emerging hatchery fry influence the emigration, realized densities, growth, habitat use, social structure, and activity patterns of localized populations of wild steelhead fry when the hatchery fry have a competitive advantage conferred by larger size and prior residence. During 1986 and 1987, the above variables were observed daily among hatchery and wild steelhead fry in laboratory stream channels for 8 weeks following emergence in June. The habitat use and social activities for fry of both origins were observed weekly in natural stream reaches from June through August in 1987 to corroborate lab findings. In lab channels, both hatchery and wild fry received 2 treatments: living alone (allopatry) and living together (sympatry). In the lab, fry of hatchery origin emerged 7 to 10 d prior to wild fry and remained larger in size during the 8 weeks of study both years. In natural stream reaches, fry of each origin were observed only in allopatric situations. Wild fry in the field emerged from natural redds while hatchery fry were released in stream reaches as unfed, newly emerged (swim-up) fry. Hatchery and wild fry in lab sections were found to be very similar in their emigration rates, distances to nearest neighbor, growth rates, and use of habitat. Both fry types, regardless of treatment or environment (lab or field), established similar stable social structure and used the same types of aggressive acts. Among all lab groups, once a fry became dominant, it retained that social status to the end of the study period. Significant differences (P<.05 both years) among comparison tests were: 1) in allopatric lab sections, wild fry maintained larger densities than hatchery fry, 2) in sympatry, hatchery fry had a greater tendency to establish stable focal points and social hierarchies more readily, defend larger areas, have better condition, prefer pools with overhead cover more frequently, be more aggressive, and reach stable densities more quickly than the wild fry, 3) fewer hatchery fry in sympatry maintained nomadic positions than wild fry in both treatments, 4) in sympatry, hatchery fry directed more acts of overt aggression toward wild fry than other hatchery fry, 5) wild fry in sympatry usually used defensive or less offensive acts of aggression when interacting with other fry, 6) fry of both origins in natural stream reaches maintained greater distances to their nearest neighbor than fry in allopatric lab sections, 7) dominant hatchery fry in both treatments maintained larger focal areas than subdominant fry, 8) hatchery fry maintained longer lengths than wild fry through the duration of the study, and 9) hatchery fry were more aggressive in sympatry than in allopatry. Potential differences (P<.05 in one year and P<.1 in the other year) were: 1) wild fry in sympatry had lower realized densities, maintained smaller focal areas, had greater proportions of nomadic individuals, and established stable social hierarchies slower than wild fry in allopatric lab sections, 2) wild fry in sympatry had poorer condition than all other fry groups in lab sections, 3) in sympatry, wild fry were the recipients of the majority of aggressive acts perpetrated by hatchery fry and other wild fry and usually assumed the subordinate positions within the social hierarchy, 4) all fry in the lab showed a high preference for pools with overhead cover and low preference for gravel and fines and run areas, and 5) wild fry in allopatric lab sections were more socially active than hatchery fry while the reverse was observed in the natural streams. Any influences that could be attributed to inherent differences between stock origins were probably masked by size differences between fry types. The study would have been more complete had I included sympatric lab sections where wild fry emerged first and where fry types emerged simultaneously, and sympatric reaches in natural streams. Results were further confounded by the limited number of wild adults used for broodstock in the lab segment of this study. Progeny produced from so few adults (5 adults of each sex each year) would have very limited genotypic variation compared to what occurs in natural streams. This may partially explain why some findings from lab sections and natural stream reaches differed. Likewise, genotypic expression among wild fry in lab sections may have varied greatly between years. This could explain differences found between years in behavior of wild fry in similar lab treatments. Although this study does not simulate all possible scenarios, results support suspicions that introductions of hatchery fry of larger size and earlier emergence into streams containing wild stocks could disrupt the social structure and negatively influence the realized densities, spatial distribution, growth, and behavior of wild juveniles in recipient streams. Close

• 2773. [Article] Effects of a Wind Energy Development on Greater Sage-Grouse Habitat Selection and Population Demographics in Southeastern Wyoming

  Western EcoSystems Technology, Inc. and Wyoming Wildlife Consultants, LLC initiated a greater sage-grouse radio-telemetry study at an existing wind energy development in southeastern Wyoming in 2009. The ...

  Citation × Citation Citation Abstract Copy Title: Effects of a Wind Energy Development on Greater Sage-Grouse Habitat Selection and Population Demographics in Southeastern Wyoming Author: LeBeau, Chad W. Western EcoSystems Technology, Inc. and Wyoming Wildlife Consultants, LLC initiated a greater sage-grouse radio-telemetry study at an existing wind energy development in southeastern Wyoming in 2009. The University of Wyoming joined this collaborative effort in January 2010, and the National Wind Coordinating Collaborative joined the effort in March 2011. The overall goal of the research was to establish the population-level effects of wind energy development on female sage-grouse seasonal habitat selection and demography. This study represents the only situation in the US where the responses of greater sage-grouse to the infrastructure associated with a wind energy development has been investigated. Our primary objective was to discern the relationship between sage-grouse nest, brood-rearing, and summer habitat selection patterns and survival parameters and the infrastructure of an existing wind energy facility. The Seven Mile Hill (SMH) study area was located north of Interstate 80 and south of the Shirley Basin in Carbon County, Wyoming, US. A control and treatment area was included in the SMH study area, with boundaries of each of these areas determined from lek locations and radio-marked female sage-grouse distributions. The Seven Mile Hill Wind Energy Facility (SWEF; located in the treatment area) consisted of 79 General Electric 1.5-MW wind turbines and approximately 29 km of access roads. The facility became fully operational in December 2008. In addition to the SWEF, other anthropogenic features present in this portion of the study area included approximately eight km of paved roads and 26 km of overhead transmission lines. The control study area had no wind turbines and was adjacent to the SWEF and south of US Highway 30/287. There were approximately 50 km of paved roads and 17 km of overhead transmission lines in this area. The treatment area had four leks that had an average distance of 1.93 km from the nearest SWEF turbines (range = 0.53 to 4.15 km), while the control group consisted of 6 leks with an average distance of 10.99 km from the nearest SWEF turbine (range = 7.09 to 16.16 km). We captured and radio-equipped 346 (160 treatment; 186 control) female sage-grouse within an area consisting of a wind energy development and a control area absent of wind energy development in southeastern Wyoming from 2009–2014. We relocated each radio-marked female approximately twice a week during the nesting, brood rearing, and summer periods. We developed a suite of anthropogenic, vegetation, and environmental covariates to estimate habitat selection and survival for all sage-grouse during the nesting, brood rearing, and summer periods. We used a discrete choice habitat selection model to estimate the relative probability of sage-grouse nest site, brood-rearing, and summer habitat selection within both the control and treatment areas during the post-development period. We did not detect a negative impact of the wind energy facility on nest site selection during the study period. Sage-grouse rearing broods generally avoided suitable brood-rearing habitat near anthropogenic infrastructure that includes wind energy development, major paved roads and transmission lines. Although avoidance was consistent across the years of our study, avoidance of wind turbines was more pronounced in 2012-2014 compared to 2009-2011, suggesting a lag period in the ultimate population-level response to the development of a wind energy facility. Although distance to turbine was not strongly associated with summer habitat selection, the percentage of disturbance associated with wind energy infrastructure did appear to influence summer habitat selection. In addition, we estimated survival during each seasonal period to estimate the effect of the SWEF on population fitness. The SWEF did not have a negative effect on sage-grouse nest survival within the study area over the six-year period, and nest survival did not differ between nests of females captured at treatment and control area leks over the study period. The SWEF did not have a negative effect on sage-grouse brood survival within the study area over the six-year period. Survival was related to habitat features and anthropogenic features that have existed on the landscape for >10 years. Lastly, the SWEF did not have a negative effect on female sage-grouse summer survival within the study area over the six-year period. After controlling for annual and natural variability, we observed a positive effect of the SWEF on female survival when the percentage of disturbance within 0.81 km of a sage-grouse location increased from 0% to 3%. Our study is the first to estimate the impacts of wind energy development on sage-grouse habitat selection and fitness parameters. Female sage-grouse selection of seasonal habitats was variable relative to the infrastructure associated with wind energy facility, but fitness parameters did not appear to be influenced to a great degree by the infrastructure. This pattern of effect is similar to greater prairie-chicken response to a wind energy facility in Kansas but opposite of sage-grouse response to oil and gas development. Ideally, we would have preconstruction data to identify changes in the population and decipher mechanisms in sage-grouse response to infrastructure; however, we are confident that if such impacts to habitat selection and survival did occur then we would have been able to detect these changes over the 6-year study period. The lack of other studies investigating impacts from wind energy development to sage-grouse habitat selection and survival limits our ability to make inferences about the cumulative impacts of wind energy development on sage-grouse, but we were able to describe some of the impacts that wind energy developments may have on sage-grouse populations. Although we attempted to account for possible confounding factors, there is the chance that we did not detect important interactions between environmental features and habitat selection and survival patterns. Future wind energy developments should consider the potential impacts of wind energy development on sage-grouse habitat selection patterns and survival parameters. We recommend facilities similar in size that occupy similar habitats as our study be placed 1.20 km from any occupied sage-grouse nesting, brood-rearing, or summer habitats. We recommend that future research consider predator-prey mechanisms by estimating both avian and mammalian predator densities to better understand the impacts of wind energy development on sage-grouse fitness parameters and to develop appropriate mitigation measures. Title: Effects of a Wind Energy Development on Greater Sage-Grouse Habitat Selection and Population Demographics in Southeastern Wyoming Author: LeBeau, Chad W. Western EcoSystems Technology, Inc. and Wyoming Wildlife Consultants, LLC initiated a greater sage-grouse radio-telemetry study at an existing wind energy development in southeastern Wyoming in 2009. The University of Wyoming joined this collaborative effort in January 2010, and the National Wind Coordinating Collaborative joined the effort in March 2011. The overall goal of the research was to establish the population-level effects of wind energy development on female sage-grouse seasonal habitat selection and demography. This study represents the only situation in the US where the responses of greater sage-grouse to the infrastructure associated with a wind energy development has been investigated. Our primary objective was to discern the relationship between sage-grouse nest, brood-rearing, and summer habitat selection patterns and survival parameters and the infrastructure of an existing wind energy facility. The Seven Mile Hill (SMH) study area was located north of Interstate 80 and south of the Shirley Basin in Carbon County, Wyoming, US. A control and treatment area was included in the SMH study area, with boundaries of each of these areas determined from lek locations and radio-marked female sage-grouse distributions. The Seven Mile Hill Wind Energy Facility (SWEF; located in the treatment area) consisted of 79 General Electric 1.5-MW wind turbines and approximately 29 km of access roads. The facility became fully operational in December 2008. In addition to the SWEF, other anthropogenic features present in this portion of the study area included approximately eight km of paved roads and 26 km of overhead transmission lines. The control study area had no wind turbines and was adjacent to the SWEF and south of US Highway 30/287. There were approximately 50 km of paved roads and 17 km of overhead transmission lines in this area. The treatment area had four leks that had an average distance of 1.93 km from the nearest SWEF turbines (range = 0.53 to 4.15 km), while the control group consisted of 6 leks with an average distance of 10.99 km from the nearest SWEF turbine (range = 7.09 to 16.16 km). We captured and radio-equipped 346 (160 treatment; 186 control) female sage-grouse within an area consisting of a wind energy development and a control area absent of wind energy development in southeastern Wyoming from 2009–2014. We relocated each radio-marked female approximately twice a week during the nesting, brood rearing, and summer periods. We developed a suite of anthropogenic, vegetation, and environmental covariates to estimate habitat selection and survival for all sage-grouse during the nesting, brood rearing, and summer periods. We used a discrete choice habitat selection model to estimate the relative probability of sage-grouse nest site, brood-rearing, and summer habitat selection within both the control and treatment areas during the post-development period. We did not detect a negative impact of the wind energy facility on nest site selection during the study period. Sage-grouse rearing broods generally avoided suitable brood-rearing habitat near anthropogenic infrastructure that includes wind energy development, major paved roads and transmission lines. Although avoidance was consistent across the years of our study, avoidance of wind turbines was more pronounced in 2012-2014 compared to 2009-2011, suggesting a lag period in the ultimate population-level response to the development of a wind energy facility. Although distance to turbine was not strongly associated with summer habitat selection, the percentage of disturbance associated with wind energy infrastructure did appear to influence summer habitat selection. In addition, we estimated survival during each seasonal period to estimate the effect of the SWEF on population fitness. The SWEF did not have a negative effect on sage-grouse nest survival within the study area over the six-year period, and nest survival did not differ between nests of females captured at treatment and control area leks over the study period. The SWEF did not have a negative effect on sage-grouse brood survival within the study area over the six-year period. Survival was related to habitat features and anthropogenic features that have existed on the landscape for >10 years. Lastly, the SWEF did not have a negative effect on female sage-grouse summer survival within the study area over the six-year period. After controlling for annual and natural variability, we observed a positive effect of the SWEF on female survival when the percentage of disturbance within 0.81 km of a sage-grouse location increased from 0% to 3%. Our study is the first to estimate the impacts of wind energy development on sage-grouse habitat selection and fitness parameters. Female sage-grouse selection of seasonal habitats was variable relative to the infrastructure associated with wind energy facility, but fitness parameters did not appear to be influenced to a great degree by the infrastructure. This pattern of effect is similar to greater prairie-chicken response to a wind energy facility in Kansas but opposite of sage-grouse response to oil and gas development. Ideally, we would have preconstruction data to identify changes in the population and decipher mechanisms in sage-grouse response to infrastructure; however, we are confident that if such impacts to habitat selection and survival did occur then we would have been able to detect these changes over the 6-year study period. The lack of other studies investigating impacts from wind energy development to sage-grouse habitat selection and survival limits our ability to make inferences about the cumulative impacts of wind energy development on sage-grouse, but we were able to describe some of the impacts that wind energy developments may have on sage-grouse populations. Although we attempted to account for possible confounding factors, there is the chance that we did not detect important interactions between environmental features and habitat selection and survival patterns. Future wind energy developments should consider the potential impacts of wind energy development on sage-grouse habitat selection patterns and survival parameters. We recommend facilities similar in size that occupy similar habitats as our study be placed 1.20 km from any occupied sage-grouse nesting, brood-rearing, or summer habitats. We recommend that future research consider predator-prey mechanisms by estimating both avian and mammalian predator densities to better understand the impacts of wind energy development on sage-grouse fitness parameters and to develop appropriate mitigation measures. Close

• 2774. [Article] The legal and regulatory setting affecting timber supply on Oregon's public lands

  Graduation date:

  Citation × Citation Citation Abstract Copy Title: The legal and regulatory setting affecting timber supply on Oregon's public lands Author: Peckman, Nancy Graduation date: Title: The legal and regulatory setting affecting timber supply on Oregon's public lands Author: Peckman, Nancy Graduation date: Close

• 2775. [Article] Linkages among land use, riparian zones, and uptake and transformation of nitrate in stream ecosystems

  Land use alters the physical and biological structure of stream ecosystems and potentially alters their capacity to process nitrogen (N), an essential nutrient that has nearly doubled in abundance on the ...

  Citation × Citation Citation Abstract Copy Title: Linkages among land use, riparian zones, and uptake and transformation of nitrate in stream ecosystems Author: Sobota, Daniel J. Land use alters the physical and biological structure of stream ecosystems and potentially alters their capacity to process nitrogen (N), an essential nutrient that has nearly doubled in abundance on the biosphere during the past century from human activities. In this dissertation, I quantified uptake and transformation of nitrate (NO₃⁻) in small (≤ third-order) streams and related these dynamics to aquatic ecosystem processes, including primary production and organic matter decomposition, and attributes of riparian zone structure and vegetation composition. I also analyze patterns of stream NO₃⁻ processing among three classes of adjacent land use practices (forest, agriculture, and urban). In Chapter 2, ambient rates of NO₃⁻ uptake and transformation were measured with 24-hr releases of ¹⁵N-labeled NO₃⁻ in nine stream reaches in the Willamette River Basin of western Oregon during summer low flow (July – August). Three reaches each were surrounded by forested, agricultural or urban land use. After standardizing reaches to a 500-m length, I estimated that ≥ 20% of tracer ¹⁵NO₃⁻ was taken up by detrital and autotrophic biomass in eight of the reaches. In the remaining stream, which had the largest discharge (120 L s⁻¹) in this study, only 8% of the tracer was taken up in 500 m. Tracer labeling of detritus and autotrophic biomass and a positive correlation (rs=0.81) of uptake with gross primary production suggested that assimilation was the dominant uptake pathway in all streams. Denitrification, dissimilatory reduction of NO₃⁻ to N₂ and N₂O gases, composed 3 – 15% of ¹⁵N budgets over 500 m in two agricultural reaches and in one urban reach dominated by large slowly-turning over pools. However, denitrification was below detection limit at five of the remaining six reaches. This study showed that pathways of stream NO₃⁻ uptake and transformation differed among streams adjacent to three diverse land use practices. In Chapter 3, I quantified effects of substrate nutritional quality and inorganic N loading (as NO₃⁻) on wood breakdown in western Oregon streams. Short-term (< 2 month) breakdown rates of wood substrates of high nutritional quality (Alnus rubra; red alder) and low quality (Pseudotsuga menziesii; Douglas-fir) increased with dissolved inorganic N (11 to 111 mg N L⁻¹) across six streams (p = 0.04), but this relationship was confounded with concurrent increases in stream temperature. Across the six streams, breakdown rates of red alder were consistently double that of Douglas-fir. A longer-term study (313 d) in a coniferous forest Oregon Cascades stream suggested effects of increased NO₃⁻ availability on wood breakdown became evident after cellulose and lignin components of woody tissues began to decompose (> 4 months of incubation). Average breakdown rates substrates enriched with NO₃⁻ were higher than those incubated in low NO₃⁻ conditions, but this difference was not statistically significant. However, microbial biofilm respiration rates and activity of two enzymes involved in the breakdown of woody tissues (beta-glucosidase and phenol oxidase) on red alder had significantly greater responses to NO₃⁻ additions than on Douglas-fir after four months of incubation in the stream. Results suggest that increases in N loading to streams bordered by riparian forests with fast-growing deciduous species could increase wood breakdown rates. On the other hand, increases to N loading may have a smaller effect on wood breakdown in streams surrounded by long-lived coniferous species. In Chapter 4, I quantified patterns of stream channel and riparian zone attributes for 72 streams equally distributed among forests or grasslands, agriculture, and urban land use practices on from eight major North American regions. I also related these patterns to stream NO₃⁻ uptake determined from ¹⁵NO₃⁻ tracer releases. Agricultural and urban streams had a simplified channel structure (low width-to-depth ratio, low variation in stream depth, and high stream banks) relative to forest or grassland streams. Agricultural and urban streams also had a significantly smaller median sediment diameter (D₅₀) and fraction of benthic sediments composed by silt than in forest and grassland streams. Overstory canopy cover over the channel and in the riparian zone was lowest for agricultural streams but did not significantly differ between forest or grassland streams and urban streams. A multiple regression model showed that stream NO₃⁻ uptake decreased with increasing canopy cover, but also increased with abundance of silt in benthic sediments. This suggested NO₃⁻ uptake was strongly influenced by in-stream primary production and extent of anoxic environments (conducive for denitrification). A multiple regression model for fractional NO₃⁻ uptake by denitrification further supported the concept that extent of anoxic environments influenced overall NO₃⁻ uptake in streams. Through these studies, I demonstrated that attributes of riparian zone structure and vegetation composition can strongly influence NO₃⁻ uptake and transformation in stream ecosystems by controlling organic matter dynamics. I also have shown that riparian zone attributes vary significantly among three different land use types (forest or grassland, agriculture, and urban). Similarly, pathways of NO₃⁻ uptake and effects of NO₃⁻ on wood breakdown did or were expected to differ among different land use types / riparian zone characteristics. However, other factors besides riparian attributes, particularly level of nutrient loading, alteration of stream channel physical structure, and basin position of the stream, must be considered in concert when evaluating effects of land use on riparian zone and stream ecosystem structure and function. Title: Linkages among land use, riparian zones, and uptake and transformation of nitrate in stream ecosystems Author: Sobota, Daniel J. Land use alters the physical and biological structure of stream ecosystems and potentially alters their capacity to process nitrogen (N), an essential nutrient that has nearly doubled in abundance on the biosphere during the past century from human activities. In this dissertation, I quantified uptake and transformation of nitrate (NO₃⁻) in small (≤ third-order) streams and related these dynamics to aquatic ecosystem processes, including primary production and organic matter decomposition, and attributes of riparian zone structure and vegetation composition. I also analyze patterns of stream NO₃⁻ processing among three classes of adjacent land use practices (forest, agriculture, and urban). In Chapter 2, ambient rates of NO₃⁻ uptake and transformation were measured with 24-hr releases of ¹⁵N-labeled NO₃⁻ in nine stream reaches in the Willamette River Basin of western Oregon during summer low flow (July – August). Three reaches each were surrounded by forested, agricultural or urban land use. After standardizing reaches to a 500-m length, I estimated that ≥ 20% of tracer ¹⁵NO₃⁻ was taken up by detrital and autotrophic biomass in eight of the reaches. In the remaining stream, which had the largest discharge (120 L s⁻¹) in this study, only 8% of the tracer was taken up in 500 m. Tracer labeling of detritus and autotrophic biomass and a positive correlation (rs=0.81) of uptake with gross primary production suggested that assimilation was the dominant uptake pathway in all streams. Denitrification, dissimilatory reduction of NO₃⁻ to N₂ and N₂O gases, composed 3 – 15% of ¹⁵N budgets over 500 m in two agricultural reaches and in one urban reach dominated by large slowly-turning over pools. However, denitrification was below detection limit at five of the remaining six reaches. This study showed that pathways of stream NO₃⁻ uptake and transformation differed among streams adjacent to three diverse land use practices. In Chapter 3, I quantified effects of substrate nutritional quality and inorganic N loading (as NO₃⁻) on wood breakdown in western Oregon streams. Short-term (< 2 month) breakdown rates of wood substrates of high nutritional quality (Alnus rubra; red alder) and low quality (Pseudotsuga menziesii; Douglas-fir) increased with dissolved inorganic N (11 to 111 mg N L⁻¹) across six streams (p = 0.04), but this relationship was confounded with concurrent increases in stream temperature. Across the six streams, breakdown rates of red alder were consistently double that of Douglas-fir. A longer-term study (313 d) in a coniferous forest Oregon Cascades stream suggested effects of increased NO₃⁻ availability on wood breakdown became evident after cellulose and lignin components of woody tissues began to decompose (> 4 months of incubation). Average breakdown rates substrates enriched with NO₃⁻ were higher than those incubated in low NO₃⁻ conditions, but this difference was not statistically significant. However, microbial biofilm respiration rates and activity of two enzymes involved in the breakdown of woody tissues (beta-glucosidase and phenol oxidase) on red alder had significantly greater responses to NO₃⁻ additions than on Douglas-fir after four months of incubation in the stream. Results suggest that increases in N loading to streams bordered by riparian forests with fast-growing deciduous species could increase wood breakdown rates. On the other hand, increases to N loading may have a smaller effect on wood breakdown in streams surrounded by long-lived coniferous species. In Chapter 4, I quantified patterns of stream channel and riparian zone attributes for 72 streams equally distributed among forests or grasslands, agriculture, and urban land use practices on from eight major North American regions. I also related these patterns to stream NO₃⁻ uptake determined from ¹⁵NO₃⁻ tracer releases. Agricultural and urban streams had a simplified channel structure (low width-to-depth ratio, low variation in stream depth, and high stream banks) relative to forest or grassland streams. Agricultural and urban streams also had a significantly smaller median sediment diameter (D₅₀) and fraction of benthic sediments composed by silt than in forest and grassland streams. Overstory canopy cover over the channel and in the riparian zone was lowest for agricultural streams but did not significantly differ between forest or grassland streams and urban streams. A multiple regression model showed that stream NO₃⁻ uptake decreased with increasing canopy cover, but also increased with abundance of silt in benthic sediments. This suggested NO₃⁻ uptake was strongly influenced by in-stream primary production and extent of anoxic environments (conducive for denitrification). A multiple regression model for fractional NO₃⁻ uptake by denitrification further supported the concept that extent of anoxic environments influenced overall NO₃⁻ uptake in streams. Through these studies, I demonstrated that attributes of riparian zone structure and vegetation composition can strongly influence NO₃⁻ uptake and transformation in stream ecosystems by controlling organic matter dynamics. I also have shown that riparian zone attributes vary significantly among three different land use types (forest or grassland, agriculture, and urban). Similarly, pathways of NO₃⁻ uptake and effects of NO₃⁻ on wood breakdown did or were expected to differ among different land use types / riparian zone characteristics. However, other factors besides riparian attributes, particularly level of nutrient loading, alteration of stream channel physical structure, and basin position of the stream, must be considered in concert when evaluating effects of land use on riparian zone and stream ecosystem structure and function. Close

• 2776. [Article] All in a DNA's work : conservation genetics and monitoring of the New Zealand endemic Maui's and Hector's dolphins

  The critically endangered Maui's dolphin (Cephalorhynchus hectori maui) and the endangered Hector's dolphin (C. h. hectori) are endemic to the coastal waters of New Zealand, where their primary threat ...

  Citation × Citation Citation Abstract Copy Title: All in a DNA's work : conservation genetics and monitoring of the New Zealand endemic Maui's and Hector's dolphins Author: Hamner, Rebecca Marie The critically endangered Maui's dolphin (Cephalorhynchus hectori maui) and the endangered Hector's dolphin (C. h. hectori) are endemic to the coastal waters of New Zealand, where their primary threat is fisheries-related mortality. The Maui's dolphin is among the most critically endangered cetaceans in the world, with its remnant population primarily concentrated in approximately 140 km along the central west coast of New Zealand's North Island. Its closely related sister subspecies, the Hector's dolphin, is more abundant and offers a useful comparison for studying the Maui's dolphin. My work used genetic tools to examine demographic and genetic parameters relevant for conservation considerations regarding Maui's and Hector's dolphins, as well as to build upon past genetic baselines for the purpose of long-term genetic monitoring of these subspecies. Three genetic datasets formed the basis for most analyses: (1) Maui's 01-07, including 54 Maui's dolphin individuals sampled between 2001 and 2007 (n = 70 biopsies, 12 beachcast); (2) Maui's 10-11, including 40 Maui's dolphin individuals sampled in 2010 and 2011 (n = 69 biopsies, 1 beachcast); and (3) Hector's CB11-12, including 148 Hector's dolphin individuals sampled in Cloudy Bay in 2011 and 2012 (n = 263 biopsies). Microsatellite genotypes were used to identify individuals for a genotype recapture abundance estimate of individuals age 1⁺ (N₁₊) and for the estimation of effective population size (N[subscript e]). Both populations exhibited a high N[subscript e] relative to N₁₊, consistent with expectations given their life history characteristics and the limited data available for other dolphin species. The abundance of Maui's dolphins was confirmed to be very low, Maui's 10-11 N₁₊ = 55 (95% CL = 48 - 69), and as expected, it had much lower linkage disequilibrium N[subscript e] (61, 95% CL = 29 - 338) than Hector's CB11-12 (N[subscript e] = 207, 95% CL = 127 - 447; N₁₊ = 272, 95% CL = 236 - 323). The slightly higher Ne/N₁₊ ratio of the Maui's dolphin compared to the Hector's dolphin is consistent with a recent decline in the Maui's dolphin. Although the point estimates of both N[subscript e] and N₁₊ decreased between the two Maui's dolphin datasets (Maui's 01-07: N[subscript e] = 74, 95% CL = 37 - 318; N₁₊ = 69, 95% CL = 38 - 125), the confidence intervals widely overlapped. Maui's 10-11 had significantly fewer alleles (average 4 alleles/locus) and lower heterozygosity (H₀ = 0.316, H[subscript e] = 0.319) than Hector's CB11-12 (average 7 alleles/locus, H₀ = 0.500, H[subscript e] = 0.495; all P <0.001). Interestingly, one microsatellite locus (PPHO104) had anomalously high diversity (31 to 63 alleles) in both Hector's and Maui's dolphins and appears to be influenced by diversifying selection. The observed and expected heterozygosity, internal relatedness, and F[subscript IS] of Maui's dolphins all showed patterns consistent with a decline of the subspecies, although none differed significantly over the short time interval between the two datasets collected in 2001-07 and 2010-11. The lack of significant decline in any of the parameters analyzed for Maui's dolphins is not surprising given the low power to detect a low to moderate decline over the short interval (<1 generation) between the two sampling periods. Compared to minimum viable effective population sizes proposed to guide management decisions, the Maui's dolphin has declined below the recommended threshold of N[subscript e] = 50, recently increased to N[subscript e] ≥100, thought to be necessary to avoid inbreeding depression in the short term (5 generations, ~65.2 years for Maui's and Hector's dolphins). Additionally, both the Maui's dolphin and Cloudy Bay Hector's dolphin populations are below the recommended threshold of N[subscript e] = 500, recently increased to N[subscript e] ≥1000, thought to be necessary to preserve long-term evolutionary potential. This is less of a concern for the Cloudy Bay Hector's population, which is thought to maintain gene flow with neighboring populations. However, for the small, isolated Maui's dolphin population, inbreeding depression is likely to be an increasing concern. Furthermore, each Maui's dolphin individual holds a disproportionate amount of the total genetic variation of the subspecies and would represent a disproportionately large demographic and genetic loss if it died before realizing its reproductive potential in the population. There is, however, potential for genetic restoration by interbreeding with Hector's dolphins, as genetic monitoring of Maui's dolphins revealed the first contemporary dispersal of four (two living females, one dead female, one dead male) Hector's dolphins into the Maui's dolphin distribution. Two Hector's dolphins (one dead female neonate, one living male) were also sampled along the North Island's southwest coast, outside the presumed range of either subspecies. Together, these records provide evidence of long-distance dispersal by Hector's dolphins (≥400 km) and the possibility of an unsampled Hector's dolphin population along the southwest coast of the North Island or northern South Island. These results highlight the value of genetic monitoring for subspecies lacking distinctive physical appearances, as such discoveries are not detected by other means but have important conservation implications. Although the Maui's dolphin is critically endangered, it is not necessarily doomed to extinction. The subspecies appears to be maintaining an equal sex ratio and connectivity within its remnant range, and the highly diverse locus PPHO104 could potentially offer clues to an inbreeding avoidance mechanism. If Maui's dolphins interbreed with the recently identified Hector's dolphin immigrants, it could provide genetic restoration, enhancing chances of long-term survival of the Maui's dolphin. Continued genetic monitoring and examination of recovered carcasses for phenotypic signs of inbreeding are important for gauging genetic threats to the survival of Maui's dolphins, as well as determining if any Hector's dolphin populations appear to be declining toward the critically endangered state of the Maui's dolphin. The results of this work contributed to the decision by the New Zealand Department of Conservation and Ministry for Primary Industries to conduct an updated risk assessment for Maui's dolphins and accelerate the review of the Maui's Dolphin Threat Management Plan. Consequently, commercial and recreational set net restrictions were extended slightly to reduce entanglement risk to Maui's dolphins utilizing the southern part of their distribution, as well as any Hector's dolphins that disperse north into that area. The results related to the population of Hector's dolphins in Cloudy Bay provide information that will contribute to the upcoming review of the Hector's dolphin component of the Threat Management Plan. Title: All in a DNA's work : conservation genetics and monitoring of the New Zealand endemic Maui's and Hector's dolphins Author: Hamner, Rebecca Marie The critically endangered Maui's dolphin (Cephalorhynchus hectori maui) and the endangered Hector's dolphin (C. h. hectori) are endemic to the coastal waters of New Zealand, where their primary threat is fisheries-related mortality. The Maui's dolphin is among the most critically endangered cetaceans in the world, with its remnant population primarily concentrated in approximately 140 km along the central west coast of New Zealand's North Island. Its closely related sister subspecies, the Hector's dolphin, is more abundant and offers a useful comparison for studying the Maui's dolphin. My work used genetic tools to examine demographic and genetic parameters relevant for conservation considerations regarding Maui's and Hector's dolphins, as well as to build upon past genetic baselines for the purpose of long-term genetic monitoring of these subspecies. Three genetic datasets formed the basis for most analyses: (1) Maui's 01-07, including 54 Maui's dolphin individuals sampled between 2001 and 2007 (n = 70 biopsies, 12 beachcast); (2) Maui's 10-11, including 40 Maui's dolphin individuals sampled in 2010 and 2011 (n = 69 biopsies, 1 beachcast); and (3) Hector's CB11-12, including 148 Hector's dolphin individuals sampled in Cloudy Bay in 2011 and 2012 (n = 263 biopsies). Microsatellite genotypes were used to identify individuals for a genotype recapture abundance estimate of individuals age 1⁺ (N₁₊) and for the estimation of effective population size (N[subscript e]). Both populations exhibited a high N[subscript e] relative to N₁₊, consistent with expectations given their life history characteristics and the limited data available for other dolphin species. The abundance of Maui's dolphins was confirmed to be very low, Maui's 10-11 N₁₊ = 55 (95% CL = 48 - 69), and as expected, it had much lower linkage disequilibrium N[subscript e] (61, 95% CL = 29 - 338) than Hector's CB11-12 (N[subscript e] = 207, 95% CL = 127 - 447; N₁₊ = 272, 95% CL = 236 - 323). The slightly higher Ne/N₁₊ ratio of the Maui's dolphin compared to the Hector's dolphin is consistent with a recent decline in the Maui's dolphin. Although the point estimates of both N[subscript e] and N₁₊ decreased between the two Maui's dolphin datasets (Maui's 01-07: N[subscript e] = 74, 95% CL = 37 - 318; N₁₊ = 69, 95% CL = 38 - 125), the confidence intervals widely overlapped. Maui's 10-11 had significantly fewer alleles (average 4 alleles/locus) and lower heterozygosity (H₀ = 0.316, H[subscript e] = 0.319) than Hector's CB11-12 (average 7 alleles/locus, H₀ = 0.500, H[subscript e] = 0.495; all P <0.001). Interestingly, one microsatellite locus (PPHO104) had anomalously high diversity (31 to 63 alleles) in both Hector's and Maui's dolphins and appears to be influenced by diversifying selection. The observed and expected heterozygosity, internal relatedness, and F[subscript IS] of Maui's dolphins all showed patterns consistent with a decline of the subspecies, although none differed significantly over the short time interval between the two datasets collected in 2001-07 and 2010-11. The lack of significant decline in any of the parameters analyzed for Maui's dolphins is not surprising given the low power to detect a low to moderate decline over the short interval (<1 generation) between the two sampling periods. Compared to minimum viable effective population sizes proposed to guide management decisions, the Maui's dolphin has declined below the recommended threshold of N[subscript e] = 50, recently increased to N[subscript e] ≥100, thought to be necessary to avoid inbreeding depression in the short term (5 generations, ~65.2 years for Maui's and Hector's dolphins). Additionally, both the Maui's dolphin and Cloudy Bay Hector's dolphin populations are below the recommended threshold of N[subscript e] = 500, recently increased to N[subscript e] ≥1000, thought to be necessary to preserve long-term evolutionary potential. This is less of a concern for the Cloudy Bay Hector's population, which is thought to maintain gene flow with neighboring populations. However, for the small, isolated Maui's dolphin population, inbreeding depression is likely to be an increasing concern. Furthermore, each Maui's dolphin individual holds a disproportionate amount of the total genetic variation of the subspecies and would represent a disproportionately large demographic and genetic loss if it died before realizing its reproductive potential in the population. There is, however, potential for genetic restoration by interbreeding with Hector's dolphins, as genetic monitoring of Maui's dolphins revealed the first contemporary dispersal of four (two living females, one dead female, one dead male) Hector's dolphins into the Maui's dolphin distribution. Two Hector's dolphins (one dead female neonate, one living male) were also sampled along the North Island's southwest coast, outside the presumed range of either subspecies. Together, these records provide evidence of long-distance dispersal by Hector's dolphins (≥400 km) and the possibility of an unsampled Hector's dolphin population along the southwest coast of the North Island or northern South Island. These results highlight the value of genetic monitoring for subspecies lacking distinctive physical appearances, as such discoveries are not detected by other means but have important conservation implications. Although the Maui's dolphin is critically endangered, it is not necessarily doomed to extinction. The subspecies appears to be maintaining an equal sex ratio and connectivity within its remnant range, and the highly diverse locus PPHO104 could potentially offer clues to an inbreeding avoidance mechanism. If Maui's dolphins interbreed with the recently identified Hector's dolphin immigrants, it could provide genetic restoration, enhancing chances of long-term survival of the Maui's dolphin. Continued genetic monitoring and examination of recovered carcasses for phenotypic signs of inbreeding are important for gauging genetic threats to the survival of Maui's dolphins, as well as determining if any Hector's dolphin populations appear to be declining toward the critically endangered state of the Maui's dolphin. The results of this work contributed to the decision by the New Zealand Department of Conservation and Ministry for Primary Industries to conduct an updated risk assessment for Maui's dolphins and accelerate the review of the Maui's Dolphin Threat Management Plan. Consequently, commercial and recreational set net restrictions were extended slightly to reduce entanglement risk to Maui's dolphins utilizing the southern part of their distribution, as well as any Hector's dolphins that disperse north into that area. The results related to the population of Hector's dolphins in Cloudy Bay provide information that will contribute to the upcoming review of the Hector's dolphin component of the Threat Management Plan. Close

• 2777. [Article] Averting biodiversity collapse in tropical forest protected areas

  This is the publisher’s final pdf. The published article is copyrighted by Macmillan Publishers Limited and the Nature Publishing Group and can be found at: http://www.nature.com/nature/index.html. To ...

  Citation × Citation Citation Abstract Copy Title: Averting biodiversity collapse in tropical forest protected areas Author: Lovett, Jon, Arroyo-Rodriguez, Victor, Ewango, Corneille, Rendeiro, Julio, Dirzo, Rodolfo, Poulsen, John, Corlett, Richard, Waltert, Matthias, Cords, Marina, Goodale, Uromi, Struhsaker, Thomas, Terborgh, John, Magnusson, William, Schaab, Gertrud, Banki, Olaf, Babweteera, Fred, Foster, Mercedes, Rainey, Hugo, De Dijn, Bart, Herbinger, Ilka, Janovec, John, Montag, Luciano, Stanford, Craig, Lugo, Ariel, Guix, Juan C., Sun, I. Fang, Cannon, Charles H., Silman, Miles R., Kasangaki, Aventino, Wang, Benjamin, Surbeck, Martin, Bunyavejchewin, Sarayudh, Maisels, Fiona, Lindsell, Jeremy, Nielsen, Martin R., Krishnaswamy, Jagdish, Savini, Tommaso, Parthasarathy, N., Auzel, Philippe, Killeen, Timothy, de Almeida, Samuel Soares, Abernethy, Kate, Benitez-Malvido, Julieta, de Castilho, Carolina Volkmer, Venn, Linda, Umapathy, Govindaswamy, Carroll, Richard, Pisciotta, Katia, Arias-G, Juan Carlos, Wright, Patricia, Baker, Patrick, Jin, Chen, Round, Philip, Bruehl, Carsten A., Linsenmair, K. Eduard, McNab, Roan, Huang, Zhongliang, Itoh, Akira, Scatena, Frederick, Sloan, Sean P., Schulze, Christian, Klop, Erik, McGraw, W. Scott, Pearson, Richard, Laval, Richard, Karpanty, Sarah, Sanaiotti, Tania, Roedel, Mark-Oliver, Ickes, Kalan, Ashton, Peter, Diesmos, Arvin, Guthiga, Paul, Coates, Rosamond, Nepal, Sanjay, Kone, Inza, Plumptre, Andrew, Williams, Stephen, Goodman, Steven, van der Ploeg, Jan, Pitman, Nigel, Lattke, John, Mack, Andrew L., Brockelman, Warren, Haber, William, Wright, Debra D., Clark, Connie J., Chellam, Ravi, Smith, Thomas B., Zamzani, Franky, Reynolds, Glen, Edwards, David, Chapman, Colin, Quesada, Mauricio, Knott, Cheryl, Rajathurai, Subaraj, Renton, Katherine, Danielsen, Finn, Jiangming, Mo, Whitney, Ken, Vasudevan, Karthikeyan, Bila-Isia, Inogwabini, Estrada, Alejandro, Ivanauskas, Natalia, Whitacre, David, Timm, Robert, Congdon, Robert, Kalko, Elisabeth, Harris, David, Stewart, Kristine, Xiankai, Lu, Jackes, Betsy, da Silva, Rosa de Nazarepaes, Martins, Marlucia, Kalka, Margareta, Rivera, Jorge Vega, King, Hen-biau, Turkalo, Andrea, Clavijo, Jose, Wilkie, David, Wright, S. Joseph, Cao, Min, Sodhi, Navjot, Janzen, Daniel, Mudappa, Divya, Laurance, Susan G., Stoner, Kathryn E., Rovero, Francesco, McClearn, Deedra, Eaton, Mitchell, Hamer, Keith, Parker, Kenneth, Leal, Miguel, Norconk, Marilyn, Gale, George, Stokes, Emma, Hill, Jane, van Weerd, Merlijn, Logsdon, Willis, Fedigan, Linda, Alvarez, Patricia, Brokaw, Nicholas, Marshall, Andrew R., Dave, Chittaranjan, Seidensticker, John, Edwards, Felicity, Campbell, Mason, Useche, D. Carolina, Feer, Francois, Nabe-Nielsen, Jacob, Di Fiore, Anthony, Ouboter, Paul, Yonzon, Pralad, Watts, David, Laurance, William F., Davies, Glyn, Arroyo, Luzmila, Kudavidanage, Enoka, Blake, Stephen, Hart, John, Verea, Carlos, Tobler, Mathias, Willis, Jacalyn Giacalone, Forget, Pierre-Michel, Lentino, Miguel, Lawton, Robert, Roetgers, Christiane, Blom, Allard, Robinson, Douglas, Opiang, Muse, Tscharntke, Teja, Ribeiro, Jose Lahoz da Silva, Thompson, Jo Myers, Losos, Elizabeth, Babaasa, Dennis, Rothman, Jessica, Chao, Jung-Tai, Doran-Sheehy, Diane, Dinerstein, Eric, Harrison, Rhett, Ling-Ling, Lee, O'Donnell, Sean, Donnelly, Maureen A., Reichard, Ulrich, Leonel, Cristiane, Leighton, Mark, Bobo, Kadiri S., Kress, W. John, Fruth, Barbara, Pringle, Catherine, Thomas, Duncan, Justiniano, Hermes, Farwig, Nina, Bradshaw, Corey J. A., Sukumar, Raman, Venkataraman, Meena, Lwanga, Jeremiah, Ashton, Mark, Reynolds, Vernon, Sheil, Douglas, Riley, Erin, Siaka, Alhaji, Nakagawa, Michiko, Fashing, Peter, Urbina-Cardona, J. Nicolas, Beisiegel, Beatriz de Mello, Emmons, Louise, Weber, William, West, Paige, Reinartz, Gay, Dattaraja, H. S., Chave, Jerome, Prawiradilaga, Dewi, Jones, Trevor, Sakai, Shoko, Bass, Margot, Novotny, Vojtech This is the publisher’s final pdf. The published article is copyrighted by Macmillan Publishers Limited and the Nature Publishing Group and can be found at: http://www.nature.com/nature/index.html. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. Title: Averting biodiversity collapse in tropical forest protected areas Author: Lovett, Jon, Arroyo-Rodriguez, Victor, Ewango, Corneille, Rendeiro, Julio, Dirzo, Rodolfo, Poulsen, John, Corlett, Richard, Waltert, Matthias, Cords, Marina, Goodale, Uromi, Struhsaker, Thomas, Terborgh, John, Magnusson, William, Schaab, Gertrud, Banki, Olaf, Babweteera, Fred, Foster, Mercedes, Rainey, Hugo, De Dijn, Bart, Herbinger, Ilka, Janovec, John, Montag, Luciano, Stanford, Craig, Lugo, Ariel, Guix, Juan C., Sun, I. Fang, Cannon, Charles H., Silman, Miles R., Kasangaki, Aventino, Wang, Benjamin, Surbeck, Martin, Bunyavejchewin, Sarayudh, Maisels, Fiona, Lindsell, Jeremy, Nielsen, Martin R., Krishnaswamy, Jagdish, Savini, Tommaso, Parthasarathy, N., Auzel, Philippe, Killeen, Timothy, de Almeida, Samuel Soares, Abernethy, Kate, Benitez-Malvido, Julieta, de Castilho, Carolina Volkmer, Venn, Linda, Umapathy, Govindaswamy, Carroll, Richard, Pisciotta, Katia, Arias-G, Juan Carlos, Wright, Patricia, Baker, Patrick, Jin, Chen, Round, Philip, Bruehl, Carsten A., Linsenmair, K. Eduard, McNab, Roan, Huang, Zhongliang, Itoh, Akira, Scatena, Frederick, Sloan, Sean P., Schulze, Christian, Klop, Erik, McGraw, W. Scott, Pearson, Richard, Laval, Richard, Karpanty, Sarah, Sanaiotti, Tania, Roedel, Mark-Oliver, Ickes, Kalan, Ashton, Peter, Diesmos, Arvin, Guthiga, Paul, Coates, Rosamond, Nepal, Sanjay, Kone, Inza, Plumptre, Andrew, Williams, Stephen, Goodman, Steven, van der Ploeg, Jan, Pitman, Nigel, Lattke, John, Mack, Andrew L., Brockelman, Warren, Haber, William, Wright, Debra D., Clark, Connie J., Chellam, Ravi, Smith, Thomas B., Zamzani, Franky, Reynolds, Glen, Edwards, David, Chapman, Colin, Quesada, Mauricio, Knott, Cheryl, Rajathurai, Subaraj, Renton, Katherine, Danielsen, Finn, Jiangming, Mo, Whitney, Ken, Vasudevan, Karthikeyan, Bila-Isia, Inogwabini, Estrada, Alejandro, Ivanauskas, Natalia, Whitacre, David, Timm, Robert, Congdon, Robert, Kalko, Elisabeth, Harris, David, Stewart, Kristine, Xiankai, Lu, Jackes, Betsy, da Silva, Rosa de Nazarepaes, Martins, Marlucia, Kalka, Margareta, Rivera, Jorge Vega, King, Hen-biau, Turkalo, Andrea, Clavijo, Jose, Wilkie, David, Wright, S. Joseph, Cao, Min, Sodhi, Navjot, Janzen, Daniel, Mudappa, Divya, Laurance, Susan G., Stoner, Kathryn E., Rovero, Francesco, McClearn, Deedra, Eaton, Mitchell, Hamer, Keith, Parker, Kenneth, Leal, Miguel, Norconk, Marilyn, Gale, George, Stokes, Emma, Hill, Jane, van Weerd, Merlijn, Logsdon, Willis, Fedigan, Linda, Alvarez, Patricia, Brokaw, Nicholas, Marshall, Andrew R., Dave, Chittaranjan, Seidensticker, John, Edwards, Felicity, Campbell, Mason, Useche, D. Carolina, Feer, Francois, Nabe-Nielsen, Jacob, Di Fiore, Anthony, Ouboter, Paul, Yonzon, Pralad, Watts, David, Laurance, William F., Davies, Glyn, Arroyo, Luzmila, Kudavidanage, Enoka, Blake, Stephen, Hart, John, Verea, Carlos, Tobler, Mathias, Willis, Jacalyn Giacalone, Forget, Pierre-Michel, Lentino, Miguel, Lawton, Robert, Roetgers, Christiane, Blom, Allard, Robinson, Douglas, Opiang, Muse, Tscharntke, Teja, Ribeiro, Jose Lahoz da Silva, Thompson, Jo Myers, Losos, Elizabeth, Babaasa, Dennis, Rothman, Jessica, Chao, Jung-Tai, Doran-Sheehy, Diane, Dinerstein, Eric, Harrison, Rhett, Ling-Ling, Lee, O'Donnell, Sean, Donnelly, Maureen A., Reichard, Ulrich, Leonel, Cristiane, Leighton, Mark, Bobo, Kadiri S., Kress, W. John, Fruth, Barbara, Pringle, Catherine, Thomas, Duncan, Justiniano, Hermes, Farwig, Nina, Bradshaw, Corey J. A., Sukumar, Raman, Venkataraman, Meena, Lwanga, Jeremiah, Ashton, Mark, Reynolds, Vernon, Sheil, Douglas, Riley, Erin, Siaka, Alhaji, Nakagawa, Michiko, Fashing, Peter, Urbina-Cardona, J. Nicolas, Beisiegel, Beatriz de Mello, Emmons, Louise, Weber, William, West, Paige, Reinartz, Gay, Dattaraja, H. S., Chave, Jerome, Prawiradilaga, Dewi, Jones, Trevor, Sakai, Shoko, Bass, Margot, Novotny, Vojtech This is the publisher’s final pdf. The published article is copyrighted by Macmillan Publishers Limited and the Nature Publishing Group and can be found at: http://www.nature.com/nature/index.html. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. Close

• 2778. [Article] Range-use estimation and encounter probability for juvenile Steller sea lions (Eumetopias jubatus) in the Prince William Sound-Kenai Fjords region of Alaska

  Range, areas of concentrated activity, and dispersal characteristics for juvenile Steller sea lions Eumetopias jubatus in the endangered western population (west of 144° W in the Gulf of Alaska) are poorly ...

  Citation × Citation Citation Abstract Copy Title: Range-use estimation and encounter probability for juvenile Steller sea lions (Eumetopias jubatus) in the Prince William Sound-Kenai Fjords region of Alaska Author: Meck, Stephen R. Range, areas of concentrated activity, and dispersal characteristics for juvenile Steller sea lions Eumetopias jubatus in the endangered western population (west of 144° W in the Gulf of Alaska) are poorly understood. This study quantified space use by analyzing post-release telemetric tracking data from satellite transmitters externally attached to n = 65 juvenile (12-25 months; 72.5 to 197.6 kg) Steller sea lions (SSLs) captured in Prince William Sound (60°38'N -147°8'W) or Resurrection Bay (60°2'N -149°22'W), Alaska, from 2003-2011. The analysis divided the sample population into 3 separate groups to quantify differences in distribution and movement. These groups included sex, the season when collected, and the release type (free ranging animals which were released immediately at the site of capture, and transient juveniles which were kept in captivity for up to 12 weeks as part of a larger ongoing research program). Range-use was first estimated by using the minimum convex polygon (MCP) approach, and then followed with a probabilistic kernel density estimation (KDE) to evaluate both individual and group utilization distributions (UDs). The LCV method was chosen as the smoothing algorithm for the KDE analysis as it provided biologically meaningful results pertaining to areas of concentrated activity (generally, haulout locations). The average distance traveled by study juveniles was 2,131 ± 424 km. The animals mass at release (F[subscript 1, 63] = 1.17, p = 0.28) and age (F[subscript 1, 63] = 0.033, p = 0.86) were not significant predictors of travel distance. Initial MCP results indicated the total area encompassed by all study SSLs was 92,017 km², excluding land mass. This area was heavily influenced by the only individual that crossed over the 144°W Meridian, the dividing line between the two distinct population segments. Without this individual, the remainder of the population (n = 64) fell into an area of 58,898 km². The MCP area was highly variable, with a geometric average of 1,623.6 km². Only the groups differentiated by season displayed any significant difference in area size, with the Spring/Summer (SS) groups MCP area (Mdn = 869.7 km²) being significantly less than that of the Fall/Winter (FW) group (Mdn = 3,202.2 km²), U = 330, p = 0.012, r = -0.31. This result was not related to the length of time the tag transmitted (H(2) = 49.65, p = 0.527), nor to the number of location fixes (H(2) = 62.77, p = 0.449). The KDE UD was less variable, with 50% of the population within a range of 324-1,387 km2 (mean=690.6 km²). There were no significant differences in area use associated with sex or release type (seasonally adjusted U = 124, p = 0.205, r = -0.16 and U = 87, p = 0.285, r = -0.13, respectively). However, there were significant differences in seasonal area use: U = 328, p = 0.011, r = -0.31. There was no relationship between the UD area and the amount of time the tag remained deployed (H(2) = 45.30, p = 0.698). The kernel home range (defined as 95% of space use) represented about 52.1% of the MCP range use, with areas designated as "core" (areas where the sea lions spent fully 50% of their time) making up only about 6.27% of the entire MCP range and about 11.8% of the entire kernel home range. Area use was relatively limited – at the population level, there were a total of 6 core areas which comprised 479 km². Core areas spanned a distance of less than 200 km from the most western point at the Chiswell Islands (59°35'N -149°36'W) to the most eastern point at Glacier Island (60°54'N -147°6'W). The observed differences in area use between seasons suggest a disparity in how juvenile SSLs utilize space and distribute themselves over the course of the year. Due to their age, this variation is less likely due to reproductive considerations and may reflect localized depletion of prey near preferred haul-out sites and/or changes in predation risk. Currently, management of the endangered western and threatened eastern population segments of the Steller sea lion are largely based on population trends derived from aerial survey counts and terrestrial-based count data. The likelihood of individuals to be detected during aerial surveys, and resulting correction factors to calculate overall population size from counts of hauled-out animals remain unknown. A kernel density estimation (KDE) analysis was performed to delineate boundaries around surveyed haulout locations within Prince William Sound-Kenai Fjords (PWS-KF). To closely approximate the time in which population abundance counts are conducted, only sea lions tracked during the spring/summer (SS) months (May 10-August 10) were chosen (n = 35). A multiple state model was constructed treating the satellite location data, if it fell within a specified spatiotemporal context, as a re-encounter within a mark-recapture framework. Information to determine a dry state was obtained from the tags time-at-depth (TAD) histograms. To generate an overall terrestrial detection probability 1) The animal must have been within a KDE derived core-area that coincided with a surveyed haulout site 2) it must have been dry and 3) it must have provided at least one position during the summer months, from roughly 11:00 AM-5:00 PM AKDT. A total of 10 transition states were selected from the data. Nine states corresponded to specific surveyed land locations, with the 10th, an "at-sea" location (> 3 km from land) included as a proxy for foraging behavior. A MLogit constraint was used to aid interpretation of the multi-modal likelihood surface, and a systematic model selection process employed as outlined by Lebreton & Pradel (2002). At the individual level, the juveniles released in the spring/summer months (n = 35) had 85.3% of the surveyed haulouts within PWS-KF encompass KDE-derived core areas (defined as 50% of space use). There was no difference in the number of surveyed haulouts encompassed by core areas between sexes (F[subscript 1, 33] << 0.001, p = 0.98). For animals held captive for up to 12 weeks, 33.3% returned to the original capture site. The majority of encounter probabilities (p) fell between 0.42 and 0.78 for the selected haulouts within PWS, with the exceptions being Grotto Island and Aialik Cape, which were lower (between 0.00-0.17). The at-sea (foraging) encounter probability was 0.66 (± 1 S.E. range 0.55-0.77). Most dry state probabilities fell between 0.08-0.38, with Glacier Island higher at 0.52, ± 1 S.E. range 0.49-0.55. The combined detection probability for hauled-out animals (the product of at haul-out and dry state probabilities), fell mostly between 0.08-0.28, with a distinct group (which included Grotto Island, Aialik Cape, and Procession Rocks) having values that averaged 0.01, with a cumulative range of ≈ 0.00-0.02 (± 1 S.E.). Due to gaps present within the mark-recapture data, it was not possible to run a goodness-of-fit test to validate model fit. Therefore, actual errors probably slightly exceed the reported standard errors and provide an approximation of uncertainties. Overall, the combined detection probabilities represent an effort to combine satellite location and wet-dry state telemetry and a kernel density analysis to quantify the terrestrial detection probability of a marine mammal within a multistate modeling framework, with the ultimate goal of developing a correction factor to account for haulout behavior at each of the surveyed locations included in the study. Title: Range-use estimation and encounter probability for juvenile Steller sea lions (Eumetopias jubatus) in the Prince William Sound-Kenai Fjords region of Alaska Author: Meck, Stephen R. Range, areas of concentrated activity, and dispersal characteristics for juvenile Steller sea lions Eumetopias jubatus in the endangered western population (west of 144° W in the Gulf of Alaska) are poorly understood. This study quantified space use by analyzing post-release telemetric tracking data from satellite transmitters externally attached to n = 65 juvenile (12-25 months; 72.5 to 197.6 kg) Steller sea lions (SSLs) captured in Prince William Sound (60°38'N -147°8'W) or Resurrection Bay (60°2'N -149°22'W), Alaska, from 2003-2011. The analysis divided the sample population into 3 separate groups to quantify differences in distribution and movement. These groups included sex, the season when collected, and the release type (free ranging animals which were released immediately at the site of capture, and transient juveniles which were kept in captivity for up to 12 weeks as part of a larger ongoing research program). Range-use was first estimated by using the minimum convex polygon (MCP) approach, and then followed with a probabilistic kernel density estimation (KDE) to evaluate both individual and group utilization distributions (UDs). The LCV method was chosen as the smoothing algorithm for the KDE analysis as it provided biologically meaningful results pertaining to areas of concentrated activity (generally, haulout locations). The average distance traveled by study juveniles was 2,131 ± 424 km. The animals mass at release (F[subscript 1, 63] = 1.17, p = 0.28) and age (F[subscript 1, 63] = 0.033, p = 0.86) were not significant predictors of travel distance. Initial MCP results indicated the total area encompassed by all study SSLs was 92,017 km², excluding land mass. This area was heavily influenced by the only individual that crossed over the 144°W Meridian, the dividing line between the two distinct population segments. Without this individual, the remainder of the population (n = 64) fell into an area of 58,898 km². The MCP area was highly variable, with a geometric average of 1,623.6 km². Only the groups differentiated by season displayed any significant difference in area size, with the Spring/Summer (SS) groups MCP area (Mdn = 869.7 km²) being significantly less than that of the Fall/Winter (FW) group (Mdn = 3,202.2 km²), U = 330, p = 0.012, r = -0.31. This result was not related to the length of time the tag transmitted (H(2) = 49.65, p = 0.527), nor to the number of location fixes (H(2) = 62.77, p = 0.449). The KDE UD was less variable, with 50% of the population within a range of 324-1,387 km2 (mean=690.6 km²). There were no significant differences in area use associated with sex or release type (seasonally adjusted U = 124, p = 0.205, r = -0.16 and U = 87, p = 0.285, r = -0.13, respectively). However, there were significant differences in seasonal area use: U = 328, p = 0.011, r = -0.31. There was no relationship between the UD area and the amount of time the tag remained deployed (H(2) = 45.30, p = 0.698). The kernel home range (defined as 95% of space use) represented about 52.1% of the MCP range use, with areas designated as "core" (areas where the sea lions spent fully 50% of their time) making up only about 6.27% of the entire MCP range and about 11.8% of the entire kernel home range. Area use was relatively limited – at the population level, there were a total of 6 core areas which comprised 479 km². Core areas spanned a distance of less than 200 km from the most western point at the Chiswell Islands (59°35'N -149°36'W) to the most eastern point at Glacier Island (60°54'N -147°6'W). The observed differences in area use between seasons suggest a disparity in how juvenile SSLs utilize space and distribute themselves over the course of the year. Due to their age, this variation is less likely due to reproductive considerations and may reflect localized depletion of prey near preferred haul-out sites and/or changes in predation risk. Currently, management of the endangered western and threatened eastern population segments of the Steller sea lion are largely based on population trends derived from aerial survey counts and terrestrial-based count data. The likelihood of individuals to be detected during aerial surveys, and resulting correction factors to calculate overall population size from counts of hauled-out animals remain unknown. A kernel density estimation (KDE) analysis was performed to delineate boundaries around surveyed haulout locations within Prince William Sound-Kenai Fjords (PWS-KF). To closely approximate the time in which population abundance counts are conducted, only sea lions tracked during the spring/summer (SS) months (May 10-August 10) were chosen (n = 35). A multiple state model was constructed treating the satellite location data, if it fell within a specified spatiotemporal context, as a re-encounter within a mark-recapture framework. Information to determine a dry state was obtained from the tags time-at-depth (TAD) histograms. To generate an overall terrestrial detection probability 1) The animal must have been within a KDE derived core-area that coincided with a surveyed haulout site 2) it must have been dry and 3) it must have provided at least one position during the summer months, from roughly 11:00 AM-5:00 PM AKDT. A total of 10 transition states were selected from the data. Nine states corresponded to specific surveyed land locations, with the 10th, an "at-sea" location (> 3 km from land) included as a proxy for foraging behavior. A MLogit constraint was used to aid interpretation of the multi-modal likelihood surface, and a systematic model selection process employed as outlined by Lebreton & Pradel (2002). At the individual level, the juveniles released in the spring/summer months (n = 35) had 85.3% of the surveyed haulouts within PWS-KF encompass KDE-derived core areas (defined as 50% of space use). There was no difference in the number of surveyed haulouts encompassed by core areas between sexes (F[subscript 1, 33] << 0.001, p = 0.98). For animals held captive for up to 12 weeks, 33.3% returned to the original capture site. The majority of encounter probabilities (p) fell between 0.42 and 0.78 for the selected haulouts within PWS, with the exceptions being Grotto Island and Aialik Cape, which were lower (between 0.00-0.17). The at-sea (foraging) encounter probability was 0.66 (± 1 S.E. range 0.55-0.77). Most dry state probabilities fell between 0.08-0.38, with Glacier Island higher at 0.52, ± 1 S.E. range 0.49-0.55. The combined detection probability for hauled-out animals (the product of at haul-out and dry state probabilities), fell mostly between 0.08-0.28, with a distinct group (which included Grotto Island, Aialik Cape, and Procession Rocks) having values that averaged 0.01, with a cumulative range of ≈ 0.00-0.02 (± 1 S.E.). Due to gaps present within the mark-recapture data, it was not possible to run a goodness-of-fit test to validate model fit. Therefore, actual errors probably slightly exceed the reported standard errors and provide an approximation of uncertainties. Overall, the combined detection probabilities represent an effort to combine satellite location and wet-dry state telemetry and a kernel density analysis to quantify the terrestrial detection probability of a marine mammal within a multistate modeling framework, with the ultimate goal of developing a correction factor to account for haulout behavior at each of the surveyed locations included in the study. Close

• 2779. [Article] The influence of local fidelity and recruitment on population dynamics and specialized foraging of humpback whales in Glacier Bay and Icy Strait, Alaska

  Humpback whales (Megaptera novaeangliae, Borowski 1781) in the North Pacific migrate from mid- to high- latitude summer feeding grounds along the Pacific Rim, including areas off the coasts of the U.S., ...

  Citation × Citation Citation Abstract Copy Title: The influence of local fidelity and recruitment on population dynamics and specialized foraging of humpback whales in Glacier Bay and Icy Strait, Alaska Author: Pierszalowski, Sophie Penny Humpback whales (Megaptera novaeangliae, Borowski 1781) in the North Pacific migrate from mid- to high- latitude summer feeding grounds along the Pacific Rim, including areas off the coasts of the U.S., Canada, Russia and eastern Asia, to tropical breeding grounds each winter along Pacific coasts of Mexico and Central America as well as the offshore islands of Mexico, Hawaii, and Japan. Humpback whales in the North Pacific and elsewhere were reduced to very low numbers during a period of intense commercial exploitation that ended in 1965. As the population recovers in abundance, the range of cultural and genetic diversity that survived the exploitation-driven bottleneck is able to adapt, endure and evolve. My work uses genetic tools and photo identification data to investigate the population dynamics, mitochondrial (mt) DNA control region evolution and potential drivers of a specialized feeding behavior in a recovering subpopulation of humpback whales in the Glacier Bay and Icy Strait (GBIS) sub-region of the southeastern Alaska (SEAK) feeding ground. I first collated and reconciled available DNA profiles (mtDNA control region, 10 microsatellite loci and sex) from 556 individuals using tissue samples collected from 1987 to 2012. Photo identification records associated with 692 of 1,026 total genetic samples collected in SEAK (now archived within the SEAK DNA Register and Tissue Database) corresponded to extensive life-history information, extending back to the early 1970s, as archived within the SEAK Regional Database, curated by the National Park Service (NPS) and University of Alaska, Southeast (UAS). Changes in population structure in GBIS over 32 years (1973-2005) were investigated in order to determine whether the increase in local abundance was attributable to local fidelity and recruitment or immigration from outside of SEAK. Two temporal strata were defined: 'Founder' individuals identified between 1973-1985 (n = 74, n = 46 with DNA profiles) and 'Contemporary' individuals identified between 2004-2005 (n = 171, n = 114 with DNA profiles). There was no significant genetic differentiation between the strata, indicating that it is unlikely that the population increase within GBIS was due largely to immigration of whales from elsewhere in the North Pacific. However, two additional haplotypes were documented in the Contemporary stratum at low frequency, one of which was previously unreported in the North Pacific (haplotype A8, see below). This relative stability in haplotype frequencies over time argues for strong regional fidelity of the maternal lineages represented in GBIS between 1973 and 1985. After excluding the 42 Contemporary whales with no photo ID record of a mother or genotype available for maternity inference, at least 73.6% (n = 95) of the Contemporary stratum was either a returning Founder or a recruited descendant of a Founder female. Of all genetically confirmed females with genotypes in the Founder stratum, 96% (n = 24) were either represented in the Contemporary stratum, had at least one confirmed descendant in the Contemporary stratum, or both. This high proportion, in addition to the large proportion of the verifiable Contemporary stratum that were either returning Founders or a descendant of a Founder female, provides clear evidence for local fidelity and recruitment to GBIS. The discovery of the A8 haplotype, which differs by one base pair from a common haplotype referred to as A-, represents an increase in mtDNA diversity for the North Pacific humpback whale from 28 to 29 haplotypes. To investigate the origin of this new haplotype, we re-evaluated n = 1089 electropherograms of n = 710 individuals with A- haplotypes from both the SEAK DNA Register and Tissue Database and the ocean-wide program, SPLASH (Baker et al. 2013). From this review, we identified two individuals with the A8 haplotype (a cow and calf, both sampled in GBIS) and n = 20 individuals with clear heteroplasmy for haplotypes A-/A8. The majority of A-/A8 individuals (n = 15) were sampled in SEAK. Genotype exclusion and likelihood were used to identify one of the heteroplasmic females, #196 (first sighted in SEAK in 1982), as the likely mother of the A8 cow and grandmother of the A8 calf, establishing the inheritance and germ-line fixation of the new haplotype from the parental heteroplasmy. Based on life history records and estimates of pairwise relatedness from microsatellite genotypes, it appears likely that the A-/A8 and the A8 individuals are descendants from a common maternal ancestor one or more generations prior to the three generations documented here. Humpback whale sociality takes a distinct form in Icy Strait, where whales form large, coordinated groups with repeated membership across several decades. Twenty-one years of group association records (1985-2005, n = 2,204 groups) were used to investigate the hypothesis that kin selection influences membership in large, stable groups. Of the 2204 groups recorded, 113 consisted of 6 or more individuals; a size considered unexpectedly large assuming a Poisson distribution of group size with a mean of 1.7. A total of n = 71 individuals (n = 48 with DNA profiles) were encountered in a large group in at least one year, n = 38 individuals (n = 34 with DNA profiles) were encountered in a large group in at least two years, n = 29 individuals (n = 27 with DNA profiles) were encountered in a large group in at least three years, decreasing to n = 2 individuals (n = 2 with DNA profiles) that were encountered in a large group in at least 20 years. There were no significant differences in mtDNA frequencies between large group feeders and the Founder and Contemporary strata or when compared to whales never encountered in large groups in Icy Strait, indicating that group membership is not predominately passed through one maternal lineage. Sex ratios did not deviate significantly from 1:1 for those feeding in large groups over an increasing number of years, as would be expected if females were actively recruiting offspring into large groups. The average pairwise relatedness for large group feeders was not significantly greater than expected by chance and did not increase for those feeding in large groups over an increasing number of years. Of the 179 known offspring of females encountered in a large group, only 6% were also encountered in a large group in Icy Strait as an adult and only 2.2% in the same large group as their mother. These results indicate that kin selection is not the primary driver of membership in large, stable groups and pose an interesting dynamic in local habitat use: individuals are recruited to GBIS through local maternal fidelity but do not usually associate closely with direct maternal kin. The extensive collection of DNA profiles now archived with the individual-based data within the SEAK Regional Database allowed us to integrate genetics and photo ID to answer ecologically relevant questions regarding the whales in GBIS. Together, these results demonstrate that GBIS provide habitat for a distinct collection of individuals that exhibit strong fidelity and local recruitment, some of which engage in a highly specialized feeding behavior. Further, GBIS is a local feeding habitat for two individuals with a newly arising North Pacific mtDNA haplotype. These findings reveal local genotypic and cultural variation and highlight the importance of habitat protection for species with fine-scale habitat use and strong fidelity to local migratory destinations. Title: The influence of local fidelity and recruitment on population dynamics and specialized foraging of humpback whales in Glacier Bay and Icy Strait, Alaska Author: Pierszalowski, Sophie Penny Humpback whales (Megaptera novaeangliae, Borowski 1781) in the North Pacific migrate from mid- to high- latitude summer feeding grounds along the Pacific Rim, including areas off the coasts of the U.S., Canada, Russia and eastern Asia, to tropical breeding grounds each winter along Pacific coasts of Mexico and Central America as well as the offshore islands of Mexico, Hawaii, and Japan. Humpback whales in the North Pacific and elsewhere were reduced to very low numbers during a period of intense commercial exploitation that ended in 1965. As the population recovers in abundance, the range of cultural and genetic diversity that survived the exploitation-driven bottleneck is able to adapt, endure and evolve. My work uses genetic tools and photo identification data to investigate the population dynamics, mitochondrial (mt) DNA control region evolution and potential drivers of a specialized feeding behavior in a recovering subpopulation of humpback whales in the Glacier Bay and Icy Strait (GBIS) sub-region of the southeastern Alaska (SEAK) feeding ground. I first collated and reconciled available DNA profiles (mtDNA control region, 10 microsatellite loci and sex) from 556 individuals using tissue samples collected from 1987 to 2012. Photo identification records associated with 692 of 1,026 total genetic samples collected in SEAK (now archived within the SEAK DNA Register and Tissue Database) corresponded to extensive life-history information, extending back to the early 1970s, as archived within the SEAK Regional Database, curated by the National Park Service (NPS) and University of Alaska, Southeast (UAS). Changes in population structure in GBIS over 32 years (1973-2005) were investigated in order to determine whether the increase in local abundance was attributable to local fidelity and recruitment or immigration from outside of SEAK. Two temporal strata were defined: 'Founder' individuals identified between 1973-1985 (n = 74, n = 46 with DNA profiles) and 'Contemporary' individuals identified between 2004-2005 (n = 171, n = 114 with DNA profiles). There was no significant genetic differentiation between the strata, indicating that it is unlikely that the population increase within GBIS was due largely to immigration of whales from elsewhere in the North Pacific. However, two additional haplotypes were documented in the Contemporary stratum at low frequency, one of which was previously unreported in the North Pacific (haplotype A8, see below). This relative stability in haplotype frequencies over time argues for strong regional fidelity of the maternal lineages represented in GBIS between 1973 and 1985. After excluding the 42 Contemporary whales with no photo ID record of a mother or genotype available for maternity inference, at least 73.6% (n = 95) of the Contemporary stratum was either a returning Founder or a recruited descendant of a Founder female. Of all genetically confirmed females with genotypes in the Founder stratum, 96% (n = 24) were either represented in the Contemporary stratum, had at least one confirmed descendant in the Contemporary stratum, or both. This high proportion, in addition to the large proportion of the verifiable Contemporary stratum that were either returning Founders or a descendant of a Founder female, provides clear evidence for local fidelity and recruitment to GBIS. The discovery of the A8 haplotype, which differs by one base pair from a common haplotype referred to as A-, represents an increase in mtDNA diversity for the North Pacific humpback whale from 28 to 29 haplotypes. To investigate the origin of this new haplotype, we re-evaluated n = 1089 electropherograms of n = 710 individuals with A- haplotypes from both the SEAK DNA Register and Tissue Database and the ocean-wide program, SPLASH (Baker et al. 2013). From this review, we identified two individuals with the A8 haplotype (a cow and calf, both sampled in GBIS) and n = 20 individuals with clear heteroplasmy for haplotypes A-/A8. The majority of A-/A8 individuals (n = 15) were sampled in SEAK. Genotype exclusion and likelihood were used to identify one of the heteroplasmic females, #196 (first sighted in SEAK in 1982), as the likely mother of the A8 cow and grandmother of the A8 calf, establishing the inheritance and germ-line fixation of the new haplotype from the parental heteroplasmy. Based on life history records and estimates of pairwise relatedness from microsatellite genotypes, it appears likely that the A-/A8 and the A8 individuals are descendants from a common maternal ancestor one or more generations prior to the three generations documented here. Humpback whale sociality takes a distinct form in Icy Strait, where whales form large, coordinated groups with repeated membership across several decades. Twenty-one years of group association records (1985-2005, n = 2,204 groups) were used to investigate the hypothesis that kin selection influences membership in large, stable groups. Of the 2204 groups recorded, 113 consisted of 6 or more individuals; a size considered unexpectedly large assuming a Poisson distribution of group size with a mean of 1.7. A total of n = 71 individuals (n = 48 with DNA profiles) were encountered in a large group in at least one year, n = 38 individuals (n = 34 with DNA profiles) were encountered in a large group in at least two years, n = 29 individuals (n = 27 with DNA profiles) were encountered in a large group in at least three years, decreasing to n = 2 individuals (n = 2 with DNA profiles) that were encountered in a large group in at least 20 years. There were no significant differences in mtDNA frequencies between large group feeders and the Founder and Contemporary strata or when compared to whales never encountered in large groups in Icy Strait, indicating that group membership is not predominately passed through one maternal lineage. Sex ratios did not deviate significantly from 1:1 for those feeding in large groups over an increasing number of years, as would be expected if females were actively recruiting offspring into large groups. The average pairwise relatedness for large group feeders was not significantly greater than expected by chance and did not increase for those feeding in large groups over an increasing number of years. Of the 179 known offspring of females encountered in a large group, only 6% were also encountered in a large group in Icy Strait as an adult and only 2.2% in the same large group as their mother. These results indicate that kin selection is not the primary driver of membership in large, stable groups and pose an interesting dynamic in local habitat use: individuals are recruited to GBIS through local maternal fidelity but do not usually associate closely with direct maternal kin. The extensive collection of DNA profiles now archived with the individual-based data within the SEAK Regional Database allowed us to integrate genetics and photo ID to answer ecologically relevant questions regarding the whales in GBIS. Together, these results demonstrate that GBIS provide habitat for a distinct collection of individuals that exhibit strong fidelity and local recruitment, some of which engage in a highly specialized feeding behavior. Further, GBIS is a local feeding habitat for two individuals with a newly arising North Pacific mtDNA haplotype. These findings reveal local genotypic and cultural variation and highlight the importance of habitat protection for species with fine-scale habitat use and strong fidelity to local migratory destinations. Close

• 2780. [Article] Distribution and movements of Chinook salmon, Oncorhynchus tshawytscha, returning to the Yukon River basin

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

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