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• 51. [Article] Biological control of spider mites by the predatory mite Neoseiulus fallacis (Acari: Phytoseiidae) in ornamental nursery systems

  We identified and evaluated a phytoseiid predator as a biological control agent of multiple spider mites pests that occur in ornamental nurseries. When comparing species, Neoseiulus fallacis (Garman) had ...

  Citation × Citation Citation Abstract Copy Title: Biological control of spider mites by the predatory mite Neoseiulus fallacis (Acari: Phytoseiidae) in ornamental nursery systems Author: Pratt, Paul D. We identified and evaluated a phytoseiid predator as a biological control agent of multiple spider mites pests that occur in ornamental nurseries. When comparing species, Neoseiulus fallacis (Garman) had a wider prey range than Galendromus occidentalis (Nesbitt), a higher probability of overwintering than Neoseiulus califomicus McGregor and was equally or more effective at suppressing spider mites than either of the other 2 phytoseiids in 4 field tests. To further evaluate N. fallacis we 1) measured prey range when held with 29 ornamental pests or alternative foods under laboratory conditions, 2) tested biological control of spider mites on representative plant species at both small and large spatial scales, 3) developed release and conservation strategies of the predator, and 4) examined the efficacy of the predator in controlling recently introduced pests. Neoseiulus fallacis had greatest survival and reproduction when feeding on spider mites but eriophyid mites, other mites and pollen enhanced survivorship and, in some cases, reproduction. When inoculated into ornamental plants, spider mite suppression was "acceptable" in 81% of small scale tests and-in all large scale tests. Limitations in control occurred in tall, vertical growing plants with little foliar canopy. Inoculation of N. fallacis at low prey densities into apple rootstocks was successful at suppressing Tetranychus urticae Koch and similar to control achieved at moderate prey densities. In small scale banker plant studies, high densities of adult and immature mites of N. fallacis were produced and moved downwind to receiver plants. In field tests with receiver plants placed at greater distances, only N. fallacis adult females readily dispersed to 30 m or more. When comparing overwintering survival of adult females among plant types, N. fallacis survived most on conifers, intermediate on evergreen shrubs and least on herbaceous perennials, deciduous shrubs and shade trees. Covering plants with protective plastic reduced overwintering survival of the predator. Neoseiulus fallacis successfully suppressed the newly introduced pests Panonychus citri (McGregor) and Schizotetranychus celarius (Banks) on Skimmia japonica Thunberg and Sasaella hidaensis (Makino and Uchida), respectively. Initial studies suggest that N. fallacis can be an effective biological control agent of multiple spider mites in low-growing and selected higher-growing ornamental plants. Title: Biological control of spider mites by the predatory mite Neoseiulus fallacis (Acari: Phytoseiidae) in ornamental nursery systems Author: Pratt, Paul D. We identified and evaluated a phytoseiid predator as a biological control agent of multiple spider mites pests that occur in ornamental nurseries. When comparing species, Neoseiulus fallacis (Garman) had a wider prey range than Galendromus occidentalis (Nesbitt), a higher probability of overwintering than Neoseiulus califomicus McGregor and was equally or more effective at suppressing spider mites than either of the other 2 phytoseiids in 4 field tests. To further evaluate N. fallacis we 1) measured prey range when held with 29 ornamental pests or alternative foods under laboratory conditions, 2) tested biological control of spider mites on representative plant species at both small and large spatial scales, 3) developed release and conservation strategies of the predator, and 4) examined the efficacy of the predator in controlling recently introduced pests. Neoseiulus fallacis had greatest survival and reproduction when feeding on spider mites but eriophyid mites, other mites and pollen enhanced survivorship and, in some cases, reproduction. When inoculated into ornamental plants, spider mite suppression was "acceptable" in 81% of small scale tests and-in all large scale tests. Limitations in control occurred in tall, vertical growing plants with little foliar canopy. Inoculation of N. fallacis at low prey densities into apple rootstocks was successful at suppressing Tetranychus urticae Koch and similar to control achieved at moderate prey densities. In small scale banker plant studies, high densities of adult and immature mites of N. fallacis were produced and moved downwind to receiver plants. In field tests with receiver plants placed at greater distances, only N. fallacis adult females readily dispersed to 30 m or more. When comparing overwintering survival of adult females among plant types, N. fallacis survived most on conifers, intermediate on evergreen shrubs and least on herbaceous perennials, deciduous shrubs and shade trees. Covering plants with protective plastic reduced overwintering survival of the predator. Neoseiulus fallacis successfully suppressed the newly introduced pests Panonychus citri (McGregor) and Schizotetranychus celarius (Banks) on Skimmia japonica Thunberg and Sasaella hidaensis (Makino and Uchida), respectively. Initial studies suggest that N. fallacis can be an effective biological control agent of multiple spider mites in low-growing and selected higher-growing ornamental plants. Close

• 52. [Article] Adaptive genetic markers discriminate migratory runs of Chinook salmon (Oncorhynchus tshawytscha) amid continued gene flow

  This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by John Wiley & Sons Ltd. The published article can be found at: http://onlinelibrary.wiley.com/jo...

  Citation × Citation Citation Abstract Copy Title: Adaptive genetic markers discriminate migratory runs of Chinook salmon (Oncorhynchus tshawytscha) amid continued gene flow Author: Jacobson, Dave P., Banks, Michael A., Dill, Allen J., Kurth, Ryon, O'Malley, Kathleen G. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by John Wiley & Sons Ltd. The published article can be found at: http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1752-4571. Title: Adaptive genetic markers discriminate migratory runs of Chinook salmon (Oncorhynchus tshawytscha) amid continued gene flow Author: Jacobson, Dave P., Banks, Michael A., Dill, Allen J., Kurth, Ryon, O'Malley, Kathleen G. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by John Wiley & Sons Ltd. The published article can be found at: http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1752-4571. Close

• 53. [Article] Distribution of bats in Southeast Alaska and selection of day-roosts in trees by Keen’s myotis on Prince of Wales Island, Southeast Alaska

  We conducted capture and acoustic surveys for bats in six areas along a latitudinal gradient in Southeast Alaska from mid-May to September in 2005 and we continued surveys on Prince of Wales Island from ...

  Citation × Citation Citation Abstract Copy Title: Distribution of bats in Southeast Alaska and selection of day-roosts in trees by Keen’s myotis on Prince of Wales Island, Southeast Alaska Author: Boland, Julia L. We conducted capture and acoustic surveys for bats in six areas along a latitudinal gradient in Southeast Alaska from mid-May to September in 2005 and we continued surveys on Prince of Wales Island from mid-May to September in 2006. We determined the level of effort required to catch each species and documented ranges in morphology and periods of reproduction. We captured little brown myotis, Myotis lucifugus; California myotis, M. californicus; long-legged myotis, M. volans; and Keen’s myotis, M. keenii, and we acoustically detected and sighted the silver-haired bat, Lasionycteris noctivagans. Capture success varied by species, year, and type of capture site. Our surveys support prior research suggesting that the little brown myotis is the most abundant species in the region, although densities appear to be low relative to other parts of its range. California myotis and Keen’s myotis were captured as far north as Juneau. The long-legged myotis was captured on Wrangell and Prince of Wales Islands and the silver-haired bat was detected on Prince of Wales Island. Prince of Wales Island is the southernmost area we sampled and was the only area where all species were detected. Given low rates of detection, all species appear to occur in low densities in Southeast Alaska. Better understanding of population status and trends and examination of habitat ecology and response to forest management in the region is needed to prioritize conservation strategies. The Keen’s myotis is rare and has one of the most limited distributions of any bat species in North America. Understanding gender-specific roosting ecologies of bats at relevant spatial scales is necessary to effectively evaluate the impact of habitat alteration and prioritize conservation efforts for bats in temperate forests. We examined selection of day-roosts in trees by Keen’s myotis from mid-May to September, 2006 on Prince of Wales Island, Southeast Alaska. Our objectives were to 1) examine relationships between and determine relative importance of habitat characteristics on selection of day-roosts at three spatial scales and 2) determine if habitat associations for males and females differed at each scale. We tracked 13 females to 62 roosts in trees and 6 males to 24 roosts in trees. Features at each spatial scale appeared to influence selection of day-roosts by female Keen’s myotis, but associations were strongest at the tree scale and trees used as roosts were primarily large in diameter with structural defects and located in old-growth forests. Trees in plots around roosts of females had large mean diameters and these plots had a high abundance of roost-like trees. Roosts were generally located near to roads and streams and surrounded by landscapes with a high abundance of old-growth and riparian habitat. Associations were evident for male Keen’s myotis at each spatial scale, but associations at the landscape scale were strongest. Male Keen’s myotis exhibited flexibility with the types of roosts they chose, but tree roosts were primarily snags in early to intermediate decay surrounded by a high relative abundance of roost-like trees that were closer to roads and further from riparian habitat. Habitat associations differed between males and females at each spatial scale and differences are likely a reflection of higher energetic constraints associated with reproduction for females. Energetic benefits gained from optimal roosting habitat may be critical for successful reproduction by females. Females primarily roosted in old-growth habitat and we suggest that maintaining structural components characteristic of old growth will promote conservation of Keen’s myotis in Southeast Alaska. Title: Distribution of bats in Southeast Alaska and selection of day-roosts in trees by Keen’s myotis on Prince of Wales Island, Southeast Alaska Author: Boland, Julia L. We conducted capture and acoustic surveys for bats in six areas along a latitudinal gradient in Southeast Alaska from mid-May to September in 2005 and we continued surveys on Prince of Wales Island from mid-May to September in 2006. We determined the level of effort required to catch each species and documented ranges in morphology and periods of reproduction. We captured little brown myotis, Myotis lucifugus; California myotis, M. californicus; long-legged myotis, M. volans; and Keen’s myotis, M. keenii, and we acoustically detected and sighted the silver-haired bat, Lasionycteris noctivagans. Capture success varied by species, year, and type of capture site. Our surveys support prior research suggesting that the little brown myotis is the most abundant species in the region, although densities appear to be low relative to other parts of its range. California myotis and Keen’s myotis were captured as far north as Juneau. The long-legged myotis was captured on Wrangell and Prince of Wales Islands and the silver-haired bat was detected on Prince of Wales Island. Prince of Wales Island is the southernmost area we sampled and was the only area where all species were detected. Given low rates of detection, all species appear to occur in low densities in Southeast Alaska. Better understanding of population status and trends and examination of habitat ecology and response to forest management in the region is needed to prioritize conservation strategies. The Keen’s myotis is rare and has one of the most limited distributions of any bat species in North America. Understanding gender-specific roosting ecologies of bats at relevant spatial scales is necessary to effectively evaluate the impact of habitat alteration and prioritize conservation efforts for bats in temperate forests. We examined selection of day-roosts in trees by Keen’s myotis from mid-May to September, 2006 on Prince of Wales Island, Southeast Alaska. Our objectives were to 1) examine relationships between and determine relative importance of habitat characteristics on selection of day-roosts at three spatial scales and 2) determine if habitat associations for males and females differed at each scale. We tracked 13 females to 62 roosts in trees and 6 males to 24 roosts in trees. Features at each spatial scale appeared to influence selection of day-roosts by female Keen’s myotis, but associations were strongest at the tree scale and trees used as roosts were primarily large in diameter with structural defects and located in old-growth forests. Trees in plots around roosts of females had large mean diameters and these plots had a high abundance of roost-like trees. Roosts were generally located near to roads and streams and surrounded by landscapes with a high abundance of old-growth and riparian habitat. Associations were evident for male Keen’s myotis at each spatial scale, but associations at the landscape scale were strongest. Male Keen’s myotis exhibited flexibility with the types of roosts they chose, but tree roosts were primarily snags in early to intermediate decay surrounded by a high relative abundance of roost-like trees that were closer to roads and further from riparian habitat. Habitat associations differed between males and females at each spatial scale and differences are likely a reflection of higher energetic constraints associated with reproduction for females. Energetic benefits gained from optimal roosting habitat may be critical for successful reproduction by females. Females primarily roosted in old-growth habitat and we suggest that maintaining structural components characteristic of old growth will promote conservation of Keen’s myotis in Southeast Alaska. Close

• 54. [Article] Sequential isotopic analysis to characterize ontogenetic shifts and growth dynamics of loggerhead sea turtles (Caretta caretta)

  Ontogenetic niche theory predicts that as organisms grow they make size-specific changes in habitat use and diet to optimize growth and survival. A variety of factors contribute to growth and survival ...

  Citation × Citation Citation Abstract Copy Title: Sequential isotopic analysis to characterize ontogenetic shifts and growth dynamics of loggerhead sea turtles (Caretta caretta) Author: Ramirez, Matthew D. Ontogenetic niche theory predicts that as organisms grow they make size-specific changes in habitat use and diet to optimize growth and survival. A variety of factors contribute to growth and survival in different habitats, ultimately leading to variation in life history that can affect population dynamics. An understanding of the variation in timing of habitat shifts and fidelity to those habitats is critical for population dynamics modeling and evaluation of conservation strategies, especially for species whose population vital rates are sensitive to changes in growth and survival of critical life stages, such as the loggerhead sea turtle (Caretta caretta). Isotopic analysis of sequentially deposited structures, such as sea turtle humerus bone, provides a means of studying intraspecific life history variation. I sequentially analyzed the annual humerus bone growth increments of 84 juvenile loggerhead sea turtles for stable isotopes (δ¹³C, δ¹⁵N) to reconstruct the diet and habitat use histories of turtles undergoing an oceanic-to-neritic ontogenetic shift. I also used skeletochronological methods to evaluate the growth dynamics surrounding this transition. Generated isotopic transects were used to classify individuals into alternative life history pattern groups and were combined with body size and growth data obtained from skeletal analyses to evaluate differences in the duration, timing, and growth dynamics of ontogenetic shifts. Sea turtles that displayed increases in nitrogen stable isotope ratios (δ¹⁵N) greater than 3.0‰ over one or more years were presumed to have transitioned from oceanic to neritic diets and/or habitats based on oceanic and neritic prey isotopic information collected from the literature, and were classified into one of two life history pattern groups: discrete shifters (n = 23) completed this transition within year, while facultative shifters (n = 16) completed this transition in up to eight years. As differences in isotopic values between neritic and oceanic prey are most likely driven by differences in isotopic baselines, I propose the gradual increases in δ¹⁵N values within facultative shifters over multiple years is indicative of foraging in both oceanic and neritic habitats within growth years. Size-at-transition between habitats was similar between discrete shifters (55.1 ± 7.6 cm straightline carapace length, SCL) and facultative shifters (52.8 ± 6.9 cm SCL). Growth variance was higher for facultative shifters versus discrete shifters. Yet, mean size at transition, size-at-age relationships, and mean increment-specific growth rates were similar between turtles with alternative life history patterns. Annual growth rates generally peaked within one year of transition (31/38 of turtles), providing support for a short-term (i.e., 1-2 year) ontogenetic shift-associated growth advantage. However, there was considerable variation in the timing of maximal growth rate among turtles with some individuals exhibiting maximal growth in years prior to the ontogenetic shift (14/38 turtles). The lack of substantial differences in the timing of transition and growth dynamics between discrete and facultative shifters likely limits the influence of these alternative life history patterns on time to sexual maturity in this species, though differences in habitat-specific survival probabilities could affect loggerhead population dynamics. This study demonstrates the value of paired isotopic and skeletal analyses to the study of long-term sea turtle life history variation and its affect on growth. Title: Sequential isotopic analysis to characterize ontogenetic shifts and growth dynamics of loggerhead sea turtles (Caretta caretta) Author: Ramirez, Matthew D. Ontogenetic niche theory predicts that as organisms grow they make size-specific changes in habitat use and diet to optimize growth and survival. A variety of factors contribute to growth and survival in different habitats, ultimately leading to variation in life history that can affect population dynamics. An understanding of the variation in timing of habitat shifts and fidelity to those habitats is critical for population dynamics modeling and evaluation of conservation strategies, especially for species whose population vital rates are sensitive to changes in growth and survival of critical life stages, such as the loggerhead sea turtle (Caretta caretta). Isotopic analysis of sequentially deposited structures, such as sea turtle humerus bone, provides a means of studying intraspecific life history variation. I sequentially analyzed the annual humerus bone growth increments of 84 juvenile loggerhead sea turtles for stable isotopes (δ¹³C, δ¹⁵N) to reconstruct the diet and habitat use histories of turtles undergoing an oceanic-to-neritic ontogenetic shift. I also used skeletochronological methods to evaluate the growth dynamics surrounding this transition. Generated isotopic transects were used to classify individuals into alternative life history pattern groups and were combined with body size and growth data obtained from skeletal analyses to evaluate differences in the duration, timing, and growth dynamics of ontogenetic shifts. Sea turtles that displayed increases in nitrogen stable isotope ratios (δ¹⁵N) greater than 3.0‰ over one or more years were presumed to have transitioned from oceanic to neritic diets and/or habitats based on oceanic and neritic prey isotopic information collected from the literature, and were classified into one of two life history pattern groups: discrete shifters (n = 23) completed this transition within year, while facultative shifters (n = 16) completed this transition in up to eight years. As differences in isotopic values between neritic and oceanic prey are most likely driven by differences in isotopic baselines, I propose the gradual increases in δ¹⁵N values within facultative shifters over multiple years is indicative of foraging in both oceanic and neritic habitats within growth years. Size-at-transition between habitats was similar between discrete shifters (55.1 ± 7.6 cm straightline carapace length, SCL) and facultative shifters (52.8 ± 6.9 cm SCL). Growth variance was higher for facultative shifters versus discrete shifters. Yet, mean size at transition, size-at-age relationships, and mean increment-specific growth rates were similar between turtles with alternative life history patterns. Annual growth rates generally peaked within one year of transition (31/38 of turtles), providing support for a short-term (i.e., 1-2 year) ontogenetic shift-associated growth advantage. However, there was considerable variation in the timing of maximal growth rate among turtles with some individuals exhibiting maximal growth in years prior to the ontogenetic shift (14/38 turtles). The lack of substantial differences in the timing of transition and growth dynamics between discrete and facultative shifters likely limits the influence of these alternative life history patterns on time to sexual maturity in this species, though differences in habitat-specific survival probabilities could affect loggerhead population dynamics. This study demonstrates the value of paired isotopic and skeletal analyses to the study of long-term sea turtle life history variation and its affect on growth. Close

• 55. [Article] California condors in the Pacific Northwest : integrating history, molecular ecology, and spatial modeling for reintroduction planning

  Reintroduction programs are increasingly being used to save animals from extinction and aid in their recovery. The California Condor (Gymnogyps californianus), one of the most endangered birds in the ...

  Citation × Citation Citation Abstract Copy Title: California condors in the Pacific Northwest : integrating history, molecular ecology, and spatial modeling for reintroduction planning Author: D'Elia, Jesse Reintroduction programs are increasingly being used to save animals from extinction and aid in their recovery. The California Condor (Gymnogyps californianus), one of the most endangered birds in the world, is a remarkable example of how reintroduction programs can help rapidly increase a species' population numbers and range following a population bottleneck. Despite these gains, condors remain a critically endangered species and are absent from the northern half of their historical range. Here I evaluated questions concerning the biological feasibility of reintroducing California Condors to their former range in the Pacific Northwest using a multidisciplinary approach, employing the fields of history, molecular ecology, and spatial modeling. A review of the historical evidence, including the archeological and paleontological record, use of condors in Native American culture, and early historical accounts of explorers and naturalists, suggest that condors were once widely distributed and likely abundant in the Pacific Northwest. It is also likely that they were breeding birds in the region, rather than seasonal migrants. Examination of 526 base pairs from the control region of mitochondrial DNA (mtDNA) harvested from California Condor museum samples (n = 67) and genetic founders of the captive population (n =14) revealed 18 haplotypes in the historical population, 14 of which have not been reported previously. Only three of these haplotypes survived the genetic bottleneck, indicating > 80% reduction in haplotype richness. This substantial loss of genetic diversity is consistent with the hypothesis that condor populations were relatively abundant at the time of Euro-American contact, but declined rapidly as a result of human causes. I found no spatial sorting of haplotypes in the historical population, which suggests historical gene flow between the Pacific Northwest and southern and central California. Therefore, conservation strategies should consider restoring rangewide metapopulation connectivity when planning future reintroductions. Finally, I developed and tested activity-specific ecological niche models (nesting, roosting, and feeding) to identify areas in the Pacific Northwest that have retained ecological characteristics similar to those where condors have been observed in the last several decades. These models were integrated with information on condor movement ecology and biology to produce predictive maps of reintroduction site suitability across California, Oregon, and Washington. Ecological niche models were consistent with published knowledge of California Condor ecology, had good predictive performance when tested with data withheld from model development, and identified several candidate reintroduction areas. Results suggest that > 70% of the modeled nesting habitat and > 60% of the modeled roosting and foraging habitat in Washington, Oregon, and California is currently unoccupied. Thus, there are large unoccupied regions of the California Condor’s historical range in the Pacific Northwest that still possess relevant ecological features similar to currently occupied habitats, and therefore warrant consideration for future reintroduction efforts. In summary, this study provides foundational information to inform condor reintroductions to the Pacific Northwest. Key findings include: (1) extensive evidence that condors previously occupied the Pacific Northwest, likely in large numbers, prior to Euro-American expansion; (2) the lack of historical population structure, suggestive of historical gene flow between condor populations in the Pacific Northwest and elsewhere in the range; and, (3) identification of several candidate reintroduction areas in the Pacific Northwest that have retained environmental conditions that appear suitable for condor recovery. Title: California condors in the Pacific Northwest : integrating history, molecular ecology, and spatial modeling for reintroduction planning Author: D'Elia, Jesse Reintroduction programs are increasingly being used to save animals from extinction and aid in their recovery. The California Condor (Gymnogyps californianus), one of the most endangered birds in the world, is a remarkable example of how reintroduction programs can help rapidly increase a species' population numbers and range following a population bottleneck. Despite these gains, condors remain a critically endangered species and are absent from the northern half of their historical range. Here I evaluated questions concerning the biological feasibility of reintroducing California Condors to their former range in the Pacific Northwest using a multidisciplinary approach, employing the fields of history, molecular ecology, and spatial modeling. A review of the historical evidence, including the archeological and paleontological record, use of condors in Native American culture, and early historical accounts of explorers and naturalists, suggest that condors were once widely distributed and likely abundant in the Pacific Northwest. It is also likely that they were breeding birds in the region, rather than seasonal migrants. Examination of 526 base pairs from the control region of mitochondrial DNA (mtDNA) harvested from California Condor museum samples (n = 67) and genetic founders of the captive population (n =14) revealed 18 haplotypes in the historical population, 14 of which have not been reported previously. Only three of these haplotypes survived the genetic bottleneck, indicating > 80% reduction in haplotype richness. This substantial loss of genetic diversity is consistent with the hypothesis that condor populations were relatively abundant at the time of Euro-American contact, but declined rapidly as a result of human causes. I found no spatial sorting of haplotypes in the historical population, which suggests historical gene flow between the Pacific Northwest and southern and central California. Therefore, conservation strategies should consider restoring rangewide metapopulation connectivity when planning future reintroductions. Finally, I developed and tested activity-specific ecological niche models (nesting, roosting, and feeding) to identify areas in the Pacific Northwest that have retained ecological characteristics similar to those where condors have been observed in the last several decades. These models were integrated with information on condor movement ecology and biology to produce predictive maps of reintroduction site suitability across California, Oregon, and Washington. Ecological niche models were consistent with published knowledge of California Condor ecology, had good predictive performance when tested with data withheld from model development, and identified several candidate reintroduction areas. Results suggest that > 70% of the modeled nesting habitat and > 60% of the modeled roosting and foraging habitat in Washington, Oregon, and California is currently unoccupied. Thus, there are large unoccupied regions of the California Condor’s historical range in the Pacific Northwest that still possess relevant ecological features similar to currently occupied habitats, and therefore warrant consideration for future reintroduction efforts. In summary, this study provides foundational information to inform condor reintroductions to the Pacific Northwest. Key findings include: (1) extensive evidence that condors previously occupied the Pacific Northwest, likely in large numbers, prior to Euro-American expansion; (2) the lack of historical population structure, suggestive of historical gene flow between condor populations in the Pacific Northwest and elsewhere in the range; and, (3) identification of several candidate reintroduction areas in the Pacific Northwest that have retained environmental conditions that appear suitable for condor recovery. Close

• 56. [Article] Landscape-Level Approaches to Desert Bighorn Sheep (Ovis canadensis nelsoni) Conservation in a Changing Environment

  Landscape characteristics can strongly influence demographic and genetic processes in wildlife populations. Climate change and human land use are causing many landscapes to change rapidly, and the effects ...

  Citation × Citation Citation Abstract Copy Title: Landscape-Level Approaches to Desert Bighorn Sheep (Ovis canadensis nelsoni) Conservation in a Changing Environment Author: Creech, Tyler Graydon Landscape characteristics can strongly influence demographic and genetic processes in wildlife populations. Climate change and human land use are causing many landscapes to change rapidly, and the effects on wildlife populations must be understood to properly manage these threats and design effective conservation strategies. In this dissertation, I explored the implications of landscape heterogeneity for desert bighorn sheep (Ovis canadensis nelsoni), an ecologically and culturally important ungulate species in the southwestern United States, and demonstrated new approaches that can be applied to landscape-level conservation of many wildlife species in changing landscapes. This research focused on populations within and surrounding U.S. national parks, comprising a large portion of the desert bighorn sheep's geographic range, and utilized a genetic dataset including > 1,600 individuals that was developed during this and previous projects. Landscape resistance models have been used extensively to predict potential linkages among fragmented wildlife populations, including desert bighorn sheep, but have rarely been used to guide systematic decision-making such as prioritizing conservation actions to maximize regional connectivity. In Chapter 1, I combined network theory and landscape resistance modeling to prioritize management for connectivity, including protection and restoration of dispersal corridors and habitat patches, in a desert bighorn sheep metapopulation in the Mojave Desert. I constructed network models of genetic connectivity (potential for gene flow) and demographicconnectivity (potential for colonization of empty habitat patches). I found that the type of connectivity and the network metric used to quantify had substantial effects on prioritization results; however, I was able to identify high-priority habitat patches and corridors that were highly ranked across all combinations of the above factors. Potential diet quality varies across landscapes and through time for desert bighorn sheep and other ungulates, but is difficult to measure at fine spatial and temporal resolution using traditional field-based methods. The remotely sensed vegetation index NDVI can potentially overcome these limitations, but its relationship to diet quality has never been empirically validated for desert herbivores. In Chapter 2, I examined how strongly NDVI was associated with diet quality of desert bighorn sheep in the Mojave Desert using fecal nitrogen data from multiple years and populations, and considered the effects of temporal resolution, geographic variability, and NDVI spatial summary statistic. I found that NDVI was more reliably associated with diet quality over the entire growing season than with instantaneous diet quality for a population, and was positively associated with population genetic diversity (a proxy for long-term diet quality). Although NDVI was a useful diet quality indicator for Mojave Desert bighorn sheep, my analysis suggested that it may be unreliable if satellite data are too spatially coarse to detect microhabitats providing high-quality forage, or if diet is strongly influenced by forage items that are weakly correlated with landscape greenness. Landscape genetic studies typically rely on neutral genetic markers to explore gene flow and genetic variation, but the potential for species to adapt to changing landscapes depends on how natural selection influences adaptive genetic variation. In Chapter 3, I optimized landscape resistance models for desert bighorn sheep in three regions with different landscape characteristics, and then used genetic simulations incorporating natural selection to determine how the spread of adaptive variation is influenced by differences among landscapes. Optimized landscape resistance models differed between regions but slope, presence of water barriers, and major roads had the greatest impacts on gene flow. Differences among landscapes strongly influenced the spread of adaptive genetic variation, with faster spread in landscapes with more continuously distributed habitat and when a pre-existing allele (i.e., standing genetic variation) rather than a novel allele (i.e., mutation) served as the source of adaptive genetic variation. Climate change presents a substantial threat to desert bighorn sheep and wildlife worldwide, and adaptation may be required to persist in novel environmental conditions. Knowledge of how adaptive capacity - the potential to cope with climate change by persisting in situ or moving to more suitable ranges or microhabitats - varies across populations is needed to establish conservation priorities for minimizing climate change impacts to individual species. In Chapter 4, I explored variation in the evolutionary component of adaptive capacity for 62 desert bighorn sheep populations on and near U.S. national parks. I measured adaptive capacity of populations as a function of two factors that are strongly associated with the potential for evolutionary adaptation, genetic diversity and connectivity (estimated using a landscape resistance model from Chapter 3). Genetic diversity and connectivity were highly variable across regions and populations. I identified populations with high adaptive capacity that could serve as genetic refugia from climate change impacts (e.g., those in Death Valley and Grand Canyon National Parks), but also populations with low adaptive capacity that may require conservation actions to improve their potential for adaptation (e.g., those in eastern Utah and the southern Mojave Desert). Genetic structure analyses suggested that populations in eastern Utah were genetically distinct from the rest of the study area, likely resulting from restricted gene flow following regional population extinctions. This dissertation highlighted the effects of landscape heterogeneity on genetic and demographic processes in desert bighorn sheep populations. Collectively, the information in these chapters should help guide management of desert bighorn sheep in the face of climate change and human land use. The landscape-level approaches demonstrated here may be useful for managing many other wildlife species. Title: Landscape-Level Approaches to Desert Bighorn Sheep (Ovis canadensis nelsoni) Conservation in a Changing Environment Author: Creech, Tyler Graydon Landscape characteristics can strongly influence demographic and genetic processes in wildlife populations. Climate change and human land use are causing many landscapes to change rapidly, and the effects on wildlife populations must be understood to properly manage these threats and design effective conservation strategies. In this dissertation, I explored the implications of landscape heterogeneity for desert bighorn sheep (Ovis canadensis nelsoni), an ecologically and culturally important ungulate species in the southwestern United States, and demonstrated new approaches that can be applied to landscape-level conservation of many wildlife species in changing landscapes. This research focused on populations within and surrounding U.S. national parks, comprising a large portion of the desert bighorn sheep's geographic range, and utilized a genetic dataset including > 1,600 individuals that was developed during this and previous projects. Landscape resistance models have been used extensively to predict potential linkages among fragmented wildlife populations, including desert bighorn sheep, but have rarely been used to guide systematic decision-making such as prioritizing conservation actions to maximize regional connectivity. In Chapter 1, I combined network theory and landscape resistance modeling to prioritize management for connectivity, including protection and restoration of dispersal corridors and habitat patches, in a desert bighorn sheep metapopulation in the Mojave Desert. I constructed network models of genetic connectivity (potential for gene flow) and demographicconnectivity (potential for colonization of empty habitat patches). I found that the type of connectivity and the network metric used to quantify had substantial effects on prioritization results; however, I was able to identify high-priority habitat patches and corridors that were highly ranked across all combinations of the above factors. Potential diet quality varies across landscapes and through time for desert bighorn sheep and other ungulates, but is difficult to measure at fine spatial and temporal resolution using traditional field-based methods. The remotely sensed vegetation index NDVI can potentially overcome these limitations, but its relationship to diet quality has never been empirically validated for desert herbivores. In Chapter 2, I examined how strongly NDVI was associated with diet quality of desert bighorn sheep in the Mojave Desert using fecal nitrogen data from multiple years and populations, and considered the effects of temporal resolution, geographic variability, and NDVI spatial summary statistic. I found that NDVI was more reliably associated with diet quality over the entire growing season than with instantaneous diet quality for a population, and was positively associated with population genetic diversity (a proxy for long-term diet quality). Although NDVI was a useful diet quality indicator for Mojave Desert bighorn sheep, my analysis suggested that it may be unreliable if satellite data are too spatially coarse to detect microhabitats providing high-quality forage, or if diet is strongly influenced by forage items that are weakly correlated with landscape greenness. Landscape genetic studies typically rely on neutral genetic markers to explore gene flow and genetic variation, but the potential for species to adapt to changing landscapes depends on how natural selection influences adaptive genetic variation. In Chapter 3, I optimized landscape resistance models for desert bighorn sheep in three regions with different landscape characteristics, and then used genetic simulations incorporating natural selection to determine how the spread of adaptive variation is influenced by differences among landscapes. Optimized landscape resistance models differed between regions but slope, presence of water barriers, and major roads had the greatest impacts on gene flow. Differences among landscapes strongly influenced the spread of adaptive genetic variation, with faster spread in landscapes with more continuously distributed habitat and when a pre-existing allele (i.e., standing genetic variation) rather than a novel allele (i.e., mutation) served as the source of adaptive genetic variation. Climate change presents a substantial threat to desert bighorn sheep and wildlife worldwide, and adaptation may be required to persist in novel environmental conditions. Knowledge of how adaptive capacity - the potential to cope with climate change by persisting in situ or moving to more suitable ranges or microhabitats - varies across populations is needed to establish conservation priorities for minimizing climate change impacts to individual species. In Chapter 4, I explored variation in the evolutionary component of adaptive capacity for 62 desert bighorn sheep populations on and near U.S. national parks. I measured adaptive capacity of populations as a function of two factors that are strongly associated with the potential for evolutionary adaptation, genetic diversity and connectivity (estimated using a landscape resistance model from Chapter 3). Genetic diversity and connectivity were highly variable across regions and populations. I identified populations with high adaptive capacity that could serve as genetic refugia from climate change impacts (e.g., those in Death Valley and Grand Canyon National Parks), but also populations with low adaptive capacity that may require conservation actions to improve their potential for adaptation (e.g., those in eastern Utah and the southern Mojave Desert). Genetic structure analyses suggested that populations in eastern Utah were genetically distinct from the rest of the study area, likely resulting from restricted gene flow following regional population extinctions. This dissertation highlighted the effects of landscape heterogeneity on genetic and demographic processes in desert bighorn sheep populations. Collectively, the information in these chapters should help guide management of desert bighorn sheep in the face of climate change and human land use. The landscape-level approaches demonstrated here may be useful for managing many other wildlife species. Close

• 57. [Article] Competitive Interactions and Resource Partitioning Between Northern Spotted Owls and Barred Owls in Western Oregon

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

  Citation × Citation Citation Abstract Copy Title: Competitive Interactions and Resource Partitioning Between Northern Spotted Owls and Barred Owls in Western Oregon Author: Forsman, Eric D., Anthony, Robert G., Wiens, J. David To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article is copyrighted by the Wildlife Society and published by John Wiley & Sons, Ltd. It can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%291938-5455. Title: Competitive Interactions and Resource Partitioning Between Northern Spotted Owls and Barred Owls in Western Oregon Author: Forsman, Eric D., Anthony, Robert G., Wiens, J. David To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article is copyrighted by the Wildlife Society and published by John Wiley & Sons, Ltd. It can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%291938-5455. Close

• 58. [Article] Greater Sage-grouse conservation assessment and strategy for Oregon: A plan to maintain and enhance populations and habitat

  Greater sage-grouse (Centrocercus urophasianus) were once found in most grassland and sagebrush (Artemisia spp.) habitats east of the Cascades in Oregon. European settlement and conversion of sagebrush ...

  Citation × Citation Citation Abstract Copy Title: Greater Sage-grouse conservation assessment and strategy for Oregon: A plan to maintain and enhance populations and habitat Author: Hagen, Christian Greater sage-grouse (Centrocercus urophasianus) were once found in most grassland and sagebrush (Artemisia spp.) habitats east of the Cascades in Oregon. European settlement and conversion of sagebrush steppe into agricultural production led to extirpation of the species in the Columbia Basin by the early part of the 1900s, but sagebrush rangelands have persisted, particularly in southeast Oregon. Populations have fluctuated markedly since the mid 1900s with notable declines in populations from the 1950s to early 1970s. These patterns in populations and habitat loss are similar to those observed for greater sage-grouse throughout its range. Population declines during the latter part of the 1900s lead to considerable concern for the species and subsequent conservation planning in all western states where it occurs. This management strategy is a result of this larger conservation effort by the Western Association of Fish and Wildlife Agencies. This updated and revised Plan describes Oregon Department of Fish and Wildlife’s management of greater sage-grouse and provides guidance to public land management agencies and land managers for sage-grouse conservation. Conservation actions should be encouraged on private lands as these contain some of the more productive sites, but conservation on private land is voluntary. Highlights of updates. Population goals have been revised based on statistically more robust methods for estimating population sizes. Accomplishments in conservation, research, and monitoring that have occurred since 2005 are discussed. The Core Area approach to strategically identifying important landscapes for sage-grouse is explained in detail from model development to implementation. Finally, there have been numerous publications on sage-grouse since 2005 and that literature has been updated to the document where appropriate. This management strategy and the supporting background information is intended to promote the conservation of greater sage-grouse and intact functioning sagebrush communities in Oregon. The strategy is tied to the life history of greater sage-grouse and uses the best science available. Although this strategy focuses on conservation of greater sage-grouse, the intent is to benefit conservation needs of other sagebrush-steppe species. Oregon greater sage-grouse are important to the North American population and management actions in the state will have implications on a much larger scale. This Plan recognizes that livestock ranching operations which manage for ecologically sustainable native rangelands is compatible with sage-grouse conservation, and necessary management activities to maintain a sustainable ranching operation are not considered “development actions” under the application of the Mitigation Policy to sage-grouse habitat. This Plan provides biological recommendations for long-term conservation of sage-grouse in Oregon based on the best available science. However, ODFW recognizes that land use planners and managers may need to consider these recommendations within the context of socialeconomic issues and decisions that are the responsibility of the respective governmental bodies. Thus, the intent of this plan is to inform decision-makers regarding the biological consequences of various actions on sage-grouse, but not to dictate land management decision. This document is divided into 6 sections. Section I explains the background and philosophy of conservation approaches in this strategy. Section II provides an overview of sage-grouse biology and ecology throughout the species range. Sections III and IV provide an assessment of populations and habitat, respectively, upon which management objectives are developed and their underlying assumptions and rationale are stated. In Section V, conservation guidelines are outlined, that describe actions needed and methods for achieving habitat objectives. Section VI outlines components for Plan implementation, includes a description of the structure and role of local implementation groups, and implications for public (state and federal) land management agencies. There are 6 appendices that provide supporting information, including a new appendix about socio-economics provided by the Association of Oregon Counties. Sections III to VI of the plan were expanded, because these sections are linked to the objectives and implementation of this Plan. Populations and habitat were assessed by BLM district boundaries because; the availability of habitat measures by district, each district approximates an eco-region, and BLM is the primary land manager within most of the district boundaries. The 23 years 1980-2003 are the relevant time period to establish a benchmark for sage-grouse populations and their habitats, because the factors of predator control methods (and take levels), grazing schedules, survey protocols, habitat treatments and harvest levels of sage-grouse were similar through this period. Title: Greater Sage-grouse conservation assessment and strategy for Oregon: A plan to maintain and enhance populations and habitat Author: Hagen, Christian Greater sage-grouse (Centrocercus urophasianus) were once found in most grassland and sagebrush (Artemisia spp.) habitats east of the Cascades in Oregon. European settlement and conversion of sagebrush steppe into agricultural production led to extirpation of the species in the Columbia Basin by the early part of the 1900s, but sagebrush rangelands have persisted, particularly in southeast Oregon. Populations have fluctuated markedly since the mid 1900s with notable declines in populations from the 1950s to early 1970s. These patterns in populations and habitat loss are similar to those observed for greater sage-grouse throughout its range. Population declines during the latter part of the 1900s lead to considerable concern for the species and subsequent conservation planning in all western states where it occurs. This management strategy is a result of this larger conservation effort by the Western Association of Fish and Wildlife Agencies. This updated and revised Plan describes Oregon Department of Fish and Wildlife’s management of greater sage-grouse and provides guidance to public land management agencies and land managers for sage-grouse conservation. Conservation actions should be encouraged on private lands as these contain some of the more productive sites, but conservation on private land is voluntary. Highlights of updates. Population goals have been revised based on statistically more robust methods for estimating population sizes. Accomplishments in conservation, research, and monitoring that have occurred since 2005 are discussed. The Core Area approach to strategically identifying important landscapes for sage-grouse is explained in detail from model development to implementation. Finally, there have been numerous publications on sage-grouse since 2005 and that literature has been updated to the document where appropriate. This management strategy and the supporting background information is intended to promote the conservation of greater sage-grouse and intact functioning sagebrush communities in Oregon. The strategy is tied to the life history of greater sage-grouse and uses the best science available. Although this strategy focuses on conservation of greater sage-grouse, the intent is to benefit conservation needs of other sagebrush-steppe species. Oregon greater sage-grouse are important to the North American population and management actions in the state will have implications on a much larger scale. This Plan recognizes that livestock ranching operations which manage for ecologically sustainable native rangelands is compatible with sage-grouse conservation, and necessary management activities to maintain a sustainable ranching operation are not considered “development actions” under the application of the Mitigation Policy to sage-grouse habitat. This Plan provides biological recommendations for long-term conservation of sage-grouse in Oregon based on the best available science. However, ODFW recognizes that land use planners and managers may need to consider these recommendations within the context of socialeconomic issues and decisions that are the responsibility of the respective governmental bodies. Thus, the intent of this plan is to inform decision-makers regarding the biological consequences of various actions on sage-grouse, but not to dictate land management decision. This document is divided into 6 sections. Section I explains the background and philosophy of conservation approaches in this strategy. Section II provides an overview of sage-grouse biology and ecology throughout the species range. Sections III and IV provide an assessment of populations and habitat, respectively, upon which management objectives are developed and their underlying assumptions and rationale are stated. In Section V, conservation guidelines are outlined, that describe actions needed and methods for achieving habitat objectives. Section VI outlines components for Plan implementation, includes a description of the structure and role of local implementation groups, and implications for public (state and federal) land management agencies. There are 6 appendices that provide supporting information, including a new appendix about socio-economics provided by the Association of Oregon Counties. Sections III to VI of the plan were expanded, because these sections are linked to the objectives and implementation of this Plan. Populations and habitat were assessed by BLM district boundaries because; the availability of habitat measures by district, each district approximates an eco-region, and BLM is the primary land manager within most of the district boundaries. The 23 years 1980-2003 are the relevant time period to establish a benchmark for sage-grouse populations and their habitats, because the factors of predator control methods (and take levels), grazing schedules, survey protocols, habitat treatments and harvest levels of sage-grouse were similar through this period. Close

• 59. [Article] Forestry

  Posted by permission of Cambridge Scientific Abstracts (CSA). (c) CSA 2009. All rights reserved.

  Citation × Citation Citation Abstract Copy Title: Forestry Author: Avery, Bonnie E. Posted by permission of Cambridge Scientific Abstracts (CSA). (c) CSA 2009. All rights reserved. Title: Forestry Author: Avery, Bonnie E. Posted by permission of Cambridge Scientific Abstracts (CSA). (c) CSA 2009. All rights reserved. Close

• 60. [Article] Forestry

  Posted by permission of Cambridge Scientific Abstracts (CSA). (c) CSA 2007. All rights reserved.

  Citation × Citation Citation Abstract Copy Title: Forestry Author: Avery, Bonnie E. Posted by permission of Cambridge Scientific Abstracts (CSA). (c) CSA 2007. All rights reserved. Title: Forestry Author: Avery, Bonnie E. Posted by permission of Cambridge Scientific Abstracts (CSA). (c) CSA 2007. All rights reserved. Close