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• 81. [Article] A Terrestrial-Aquatic Food Web Subsidy is Potentially Mediated by Multiple Predator Effects on an Arboreal Crab

  Terrestrial-aquatic food web subsidies are known to affect food web structure, ecosystem productivity, and stability of recipient habitats. This study describes a prey flux across the land–water interface ...

  Citation × Citation Citation Abstract Copy Title: A Terrestrial-Aquatic Food Web Subsidy is Potentially Mediated by Multiple Predator Effects on an Arboreal Crab Author: Yeager, Lauren A., Stoner, Elizabeth W., Peters, Joseph R., Layman, Craig A. Year: 2015 Terrestrial-aquatic food web subsidies are known to affect food web structure, ecosystem productivity, and stability of recipient habitats. This study describes a prey flux across the land–water interface associated with a behavioral response to multiple predators. Specifically, mangrove tree crabs (Aratus pisonii, hereafter Aratus) are primarily arboreal, but may jump off mangrove trees to escape avian predators, making them vulnerable to fish predation. Mesocosm experiments, field observations, and tethering assays were used to investigate behavioral responses, habitat shifts, and risk for Aratus associated with these two predator types. In the field, Aratus spent most of their time above the water on mangroves, where risk is lowest. In response to simulated bird strikes in mesocosm trials, crabs jumped off trees to escape imminent risk, and spent more time in and near the water, enhancing risk of fish predation. Fish attacks on crabs were nearly three times greater in treatments with simulated bird attacks. In addition, empirical diet data was used to examine the importance of Aratus as a prey item for a fish predator. Aratus represented up to 29% of diet by volume for one of the most common mesopredators in the Caribbean (gray snapper Lutjanus griseus), with the proportion varying greatly across space. Because Aratus consume mangrove-derived carbon, their consumption by aquatic predators represents another pathway by which mangrove production may be incorporated into aquatic food webs. These data suggest how the nexus of behavioral and food web ecology may provide for new perspectives on energy flow between ecosystems. Title: A Terrestrial-Aquatic Food Web Subsidy is Potentially Mediated by Multiple Predator Effects on an Arboreal Crab Author: Yeager, Lauren A., Stoner, Elizabeth W., Peters, Joseph R., Layman, Craig A. Year: 2015 Terrestrial-aquatic food web subsidies are known to affect food web structure, ecosystem productivity, and stability of recipient habitats. This study describes a prey flux across the land–water interface associated with a behavioral response to multiple predators. Specifically, mangrove tree crabs (Aratus pisonii, hereafter Aratus) are primarily arboreal, but may jump off mangrove trees to escape avian predators, making them vulnerable to fish predation. Mesocosm experiments, field observations, and tethering assays were used to investigate behavioral responses, habitat shifts, and risk for Aratus associated with these two predator types. In the field, Aratus spent most of their time above the water on mangroves, where risk is lowest. In response to simulated bird strikes in mesocosm trials, crabs jumped off trees to escape imminent risk, and spent more time in and near the water, enhancing risk of fish predation. Fish attacks on crabs were nearly three times greater in treatments with simulated bird attacks. In addition, empirical diet data was used to examine the importance of Aratus as a prey item for a fish predator. Aratus represented up to 29% of diet by volume for one of the most common mesopredators in the Caribbean (gray snapper Lutjanus griseus), with the proportion varying greatly across space. Because Aratus consume mangrove-derived carbon, their consumption by aquatic predators represents another pathway by which mangrove production may be incorporated into aquatic food webs. These data suggest how the nexus of behavioral and food web ecology may provide for new perspectives on energy flow between ecosystems. Close

• 82. [Article] The Biodiversity and Biogeochemistry of Cryoconite Holes from McMurdo Dry Valley Glaciers, Antarctica

  Once thought of as inert, ice has been increasingly recognized as a habitat suitable for life. The landscape of the MCMurdo Dry Valleys (MCM) of Antarctica is dominated by glaciers, and glacier melt is ...

  Citation × Citation Citation Abstract Copy Title: The Biodiversity and Biogeochemistry of Cryoconite Holes from McMurdo Dry Valley Glaciers, Antarctica Author: Porazinska, Dorota L., Fountain, Andrew G., Nylen, Thomas H., Tranter, Martyn, Virginia, Ross A., Wall, Diana H. Year: 2004 Once thought of as inert, ice has been increasingly recognized as a habitat suitable for life. The landscape of the MCMurdo Dry Valleys (MCM) of Antarctica is dominated by glaciers, and glacier melt is the primary water source for life in soils, streams, and lakes. The glaciers, despite their cold and lifeless appearance, offer functioning habitats for life. The major objective of this study was to examine biogeochemical characteristics of miniecosystems present in cryoconite holes and to determine links to other components (soils, streams, and lakes) of the dry valley landscape. We examined cryoconite holes from 5 glaciers spanning the length of Taylor Valley, one of many valleys in the MCM. Cryoconite biotic communities were composed of the same species observed in streams and lakes, namely, cyanobacteria( Chlorococcus, Chroococcus, C rinalium, Oscillatoria, Nostoc, and Sprirulina), rotifers (Philodina gregaria and Cephalodella catellina), tardigrades (Acutuncus antarcticus and Hypsibius spp.), and ciliates. Biotic communities did not reflect the composition of the immediately surrounding environments, suggesting the effects of eolian mixing and transport of sediments and biota across the valley. Gradients of chemistry and biotic abundance in cryoconite holes reflected the position of each glacier in the valley. Nitrogen and organic carbon concentration patters across glaciers potentially resulted from biological activities in cryoconite holes. Properties of holes were stable from one to the next sampling season, suggesting that changes of cryoconite hole properties develop on longer than yearly time scales. Title: The Biodiversity and Biogeochemistry of Cryoconite Holes from McMurdo Dry Valley Glaciers, Antarctica Author: Porazinska, Dorota L., Fountain, Andrew G., Nylen, Thomas H., Tranter, Martyn, Virginia, Ross A., Wall, Diana H. Year: 2004 Once thought of as inert, ice has been increasingly recognized as a habitat suitable for life. The landscape of the MCMurdo Dry Valleys (MCM) of Antarctica is dominated by glaciers, and glacier melt is the primary water source for life in soils, streams, and lakes. The glaciers, despite their cold and lifeless appearance, offer functioning habitats for life. The major objective of this study was to examine biogeochemical characteristics of miniecosystems present in cryoconite holes and to determine links to other components (soils, streams, and lakes) of the dry valley landscape. We examined cryoconite holes from 5 glaciers spanning the length of Taylor Valley, one of many valleys in the MCM. Cryoconite biotic communities were composed of the same species observed in streams and lakes, namely, cyanobacteria( Chlorococcus, Chroococcus, C rinalium, Oscillatoria, Nostoc, and Sprirulina), rotifers (Philodina gregaria and Cephalodella catellina), tardigrades (Acutuncus antarcticus and Hypsibius spp.), and ciliates. Biotic communities did not reflect the composition of the immediately surrounding environments, suggesting the effects of eolian mixing and transport of sediments and biota across the valley. Gradients of chemistry and biotic abundance in cryoconite holes reflected the position of each glacier in the valley. Nitrogen and organic carbon concentration patters across glaciers potentially resulted from biological activities in cryoconite holes. Properties of holes were stable from one to the next sampling season, suggesting that changes of cryoconite hole properties develop on longer than yearly time scales. Close

• 83. [Article] Potential Fossil Endoliths in Vesicular Pillow Basalt, Coral Patch Seamount, Eastern North Atlantic Ocean

  The chilled rinds of pillow basalt from the Ampere-Coral Patch Seamounts in the eastern North Atlantic were studied as a potential habitat of microbial life. A variety of putative biogenic structures, ...

  Citation × Citation Citation Abstract Copy Title: Potential Fossil Endoliths in Vesicular Pillow Basalt, Coral Patch Seamount, Eastern North Atlantic Ocean Author: Cavalazzi, Barbara, Westall, Frances, Cady, Sherry L., Barbieri, Roberto, Foucher, Frédéric Year: 2011 The chilled rinds of pillow basalt from the Ampere-Coral Patch Seamounts in the eastern North Atlantic were studied as a potential habitat of microbial life. A variety of putative biogenic structures, which include filamentous and spherical microfossil-like structures, were detected in K-phillipsite-filled amygdules within the chilled rinds. The filamentous structures (similar to 2.5 mu m in diameter) occur as K-phillipsite tubules surrounded by an Fe-oxyhydroxide (lepidocrocite) rich membranous structure, whereas the spherical structures (from 4 to 2 mu m in diameter) are associated with Ti oxide (anatase) and carbonaceous matter. Several lines of evidence indicate that the microfossil-like structures in the pillow basalt are the fossilized remains of microorganisms. Possible biosignatures include the carbonaceous nature of the spherical structures, their size distributions and morphology, the presence and distribution of native fluorescence, mineralogical and chemical composition, and environmental context. When taken together, the suite of possible biosignatures supports the hypothesis that the fossil-like structures are of biological origin. The vesicular microhabitat of the rock matrix is likely to have hosted a cryptoendolithic microbial community. This study documents a variety of evidence for past microbial life in a hitherto poorly investigated and underestimated microenvironment, as represented by the amygdules in the chilled pillow basalt rinds. This kind of endolithic volcanic habitat would have been common on the early rocky planets in our Solar System, such as Earth and Mars. This study provides a framework for evaluating traces of past life in vesicular pillow basalts, regardless of whether they occur on early Earth or Mars. Title: Potential Fossil Endoliths in Vesicular Pillow Basalt, Coral Patch Seamount, Eastern North Atlantic Ocean Author: Cavalazzi, Barbara, Westall, Frances, Cady, Sherry L., Barbieri, Roberto, Foucher, Frédéric Year: 2011 The chilled rinds of pillow basalt from the Ampere-Coral Patch Seamounts in the eastern North Atlantic were studied as a potential habitat of microbial life. A variety of putative biogenic structures, which include filamentous and spherical microfossil-like structures, were detected in K-phillipsite-filled amygdules within the chilled rinds. The filamentous structures (similar to 2.5 mu m in diameter) occur as K-phillipsite tubules surrounded by an Fe-oxyhydroxide (lepidocrocite) rich membranous structure, whereas the spherical structures (from 4 to 2 mu m in diameter) are associated with Ti oxide (anatase) and carbonaceous matter. Several lines of evidence indicate that the microfossil-like structures in the pillow basalt are the fossilized remains of microorganisms. Possible biosignatures include the carbonaceous nature of the spherical structures, their size distributions and morphology, the presence and distribution of native fluorescence, mineralogical and chemical composition, and environmental context. When taken together, the suite of possible biosignatures supports the hypothesis that the fossil-like structures are of biological origin. The vesicular microhabitat of the rock matrix is likely to have hosted a cryptoendolithic microbial community. This study documents a variety of evidence for past microbial life in a hitherto poorly investigated and underestimated microenvironment, as represented by the amygdules in the chilled pillow basalt rinds. This kind of endolithic volcanic habitat would have been common on the early rocky planets in our Solar System, such as Earth and Mars. This study provides a framework for evaluating traces of past life in vesicular pillow basalts, regardless of whether they occur on early Earth or Mars. Close

• 84. [Article] Environmental Factors Influencing Diatom Communities in Antarctic Cryoconite Holes

  Cryoconite holes are ice-bound habitats that can act as refuges for aquatic and terrestrial microorganisms on glacier surfaces. In the McMurdo Dry Valleys of Antarctica, these holes are often capped by ...

  Citation × Citation Citation Abstract Copy Title: Environmental Factors Influencing Diatom Communities in Antarctic Cryoconite Holes Author: Stanish, Lee F., Bagshaw, Elizabeth A., McKnight, Diane M., Fountain, Andrew G., Tranter, Martyn Year: 2013 Cryoconite holes are ice-bound habitats that can act as refuges for aquatic and terrestrial microorganisms on glacier surfaces. In the McMurdo Dry Valleys of Antarctica, these holes are often capped by an ice lid that prevents the exchange of material and gases with the surrounding atmosphere and aquatic environment. Diatoms have been documented in cryoconite holes, and recent findings suggest that these habitats may harbour a distinctive diatom flora compared to the surrounding aquatic environments. In this study, we examined diatom community composition in cryoconite holes and environmental correlates across three glaciers in Taylor Valley, Antarctica. The diatom communities were dominated by two genera, Muelleriaand Diadesmis, both of which had high viability and could have been seeded from the surrounding ephemeral streams. The location of the cryoconite hole within the valley was a key determinant of community composition. A diatom species richness gradient was observed that corresponded to distance inland from the coast and co-varied with species richness in streams within the same lake basin. Cryoconite holes that were adjacent to streams with higher diversity displayed greater species richness. However, physical factors, such as the ability to withstand freeze–thaw conditions and to colonize coarse sediments, acted as additional selective filters and influenced diatom diversity, viability and community composition. Title: Environmental Factors Influencing Diatom Communities in Antarctic Cryoconite Holes Author: Stanish, Lee F., Bagshaw, Elizabeth A., McKnight, Diane M., Fountain, Andrew G., Tranter, Martyn Year: 2013 Cryoconite holes are ice-bound habitats that can act as refuges for aquatic and terrestrial microorganisms on glacier surfaces. In the McMurdo Dry Valleys of Antarctica, these holes are often capped by an ice lid that prevents the exchange of material and gases with the surrounding atmosphere and aquatic environment. Diatoms have been documented in cryoconite holes, and recent findings suggest that these habitats may harbour a distinctive diatom flora compared to the surrounding aquatic environments. In this study, we examined diatom community composition in cryoconite holes and environmental correlates across three glaciers in Taylor Valley, Antarctica. The diatom communities were dominated by two genera, Muelleriaand Diadesmis, both of which had high viability and could have been seeded from the surrounding ephemeral streams. The location of the cryoconite hole within the valley was a key determinant of community composition. A diatom species richness gradient was observed that corresponded to distance inland from the coast and co-varied with species richness in streams within the same lake basin. Cryoconite holes that were adjacent to streams with higher diversity displayed greater species richness. However, physical factors, such as the ability to withstand freeze–thaw conditions and to colonize coarse sediments, acted as additional selective filters and influenced diatom diversity, viability and community composition. Close

• 85. [Article] A Review of Urban Water Body Challenges and Approaches: (1) Rehabilitation and Remediation

  We review how urbanization alters aquatic ecosystems, as well as actions that managers can take to remediate urban waters. Urbanization affects streams by fundamentally altering longitudinal and lateral ...

  Citation × Citation Citation Abstract Copy Title: A Review of Urban Water Body Challenges and Approaches: (1) Rehabilitation and Remediation Author: Hughes, Robert M., Dunham, Susie, Maas-Hebner, Kathleen G., Yeakley, J. Alan, Schreck, Carl B., Harte, Michael, Molina, Nancy, Shock, Clinton C., Kaczynski, Victor W., Schaeffer, Jeff Year: 2014 We review how urbanization alters aquatic ecosystems, as well as actions that managers can take to remediate urban waters. Urbanization affects streams by fundamentally altering longitudinal and lateral processes that in turn alter hydrology, habitat, and water chemistry; these effects create physical and chemical stressors that in turn affect the biota. Urban streams often suffer from multiple stressor effects that have collectively been termed an “urban stream syndrome,” in which no single factor dominates degraded conditions. Resource managers have multiple ways of combating the urban stream syndrome. These approaches range from whole-watershed protection to reach-scale habitat rehabilitation, but the prescription must be matched to the scale of the factors that are causing the problem, and results will likely not be immediate because of lengthy recovery times. Although pristine or reference conditions are far from attainable, urban stream rehabilitation is a worthy goal because appropriate actions can provide ecosystem improvements as well as increased ecosystem service benefits for human society. Title: A Review of Urban Water Body Challenges and Approaches: (1) Rehabilitation and Remediation Author: Hughes, Robert M., Dunham, Susie, Maas-Hebner, Kathleen G., Yeakley, J. Alan, Schreck, Carl B., Harte, Michael, Molina, Nancy, Shock, Clinton C., Kaczynski, Victor W., Schaeffer, Jeff Year: 2014 We review how urbanization alters aquatic ecosystems, as well as actions that managers can take to remediate urban waters. Urbanization affects streams by fundamentally altering longitudinal and lateral processes that in turn alter hydrology, habitat, and water chemistry; these effects create physical and chemical stressors that in turn affect the biota. Urban streams often suffer from multiple stressor effects that have collectively been termed an “urban stream syndrome,” in which no single factor dominates degraded conditions. Resource managers have multiple ways of combating the urban stream syndrome. These approaches range from whole-watershed protection to reach-scale habitat rehabilitation, but the prescription must be matched to the scale of the factors that are causing the problem, and results will likely not be immediate because of lengthy recovery times. Although pristine or reference conditions are far from attainable, urban stream rehabilitation is a worthy goal because appropriate actions can provide ecosystem improvements as well as increased ecosystem service benefits for human society. Close

• 86. [Article] Breeding Trouble: West Nile on the Willamette?

  From the Roman aqueducts to Bonneville Dam, humans have built structures to moderate the extremes of natural water flow. Some of these structures, from Roman cisterns to the catch basins under modern city ...

  Citation × Citation Citation Abstract Copy Title: Breeding Trouble: West Nile on the Willamette? Author: Karr, Merilee Year: 2005 From the Roman aqueducts to Bonneville Dam, humans have built structures to moderate the extremes of natural water flow. Some of these structures, from Roman cisterns to the catch basins under modern city streets, have inadvertently supplied mosquitoes with the standing water in which they thrive and multiply. Even more mosquito habitat may have been created in the last decade by a change in the Clean Water Act. The original drive behind the Act, in 1972, was the elimination of point-source pollution: sewage and industrial discharge into waterways. In the 1990s new regulations aimed to prevent non-point-source pollution, due to urban stormwater runoff. There are two basic methods of cleaning stormwater: filtering, through earth, vegetation or manufactured filters; and settling, retaining the water behind a barrier to let particulates sink to the bottom. New studies show that water retention methods, such as the familiar catch basin, may breed mosquitoes. Even if retention structures are designed to minimize mosquito habitat by draining quickly, they may clog and accumulate standing water without regular maintenance. Title: Breeding Trouble: West Nile on the Willamette? Author: Karr, Merilee Year: 2005 From the Roman aqueducts to Bonneville Dam, humans have built structures to moderate the extremes of natural water flow. Some of these structures, from Roman cisterns to the catch basins under modern city streets, have inadvertently supplied mosquitoes with the standing water in which they thrive and multiply. Even more mosquito habitat may have been created in the last decade by a change in the Clean Water Act. The original drive behind the Act, in 1972, was the elimination of point-source pollution: sewage and industrial discharge into waterways. In the 1990s new regulations aimed to prevent non-point-source pollution, due to urban stormwater runoff. There are two basic methods of cleaning stormwater: filtering, through earth, vegetation or manufactured filters; and settling, retaining the water behind a barrier to let particulates sink to the bottom. New studies show that water retention methods, such as the familiar catch basin, may breed mosquitoes. Even if retention structures are designed to minimize mosquito habitat by draining quickly, they may clog and accumulate standing water without regular maintenance. Close

• 87. [Article] Divergent trends in ecosystem services under different climate-management futures in a fire-prone forest landscape

  While ecosystem services and climate change are often examined independently, quantitative assessments integrating these fields are needed to inform future land management decisions. Using climate-informed ...

  Citation × Citation Citation Abstract Copy Title: Divergent trends in ecosystem services under different climate-management futures in a fire-prone forest landscape Author: Halofsky, Joshua S., Halofsky, Jessica E., Hemstrom, Miles A., Morzillo, Anita T., Zhou, Xiaoping, Donato, Daniel C. Year: 2017 While ecosystem services and climate change are often examined independently, quantitative assessments integrating these fields are needed to inform future land management decisions. Using climate-informed state-and-transition simulations, we examined projected trends and trade-offs for a suite of ecosystem services under four climate change scenarios and two management scenarios (active management emphasizing fuel treatments and no management other than fire suppression) in a fire-prone landscape of dry and moist mixed-conifer forests in central Oregon, USA. Focal ecosystem services included fire potential (regulating service), timber volume (provisioning service), and potential wildlife habitat (supporting service). Projections without climate change suggested active management in dry mixed-conifer forests would create more open forest structures, reduce crown fire potential, and maintain timber stocks, while in moist mixed-conifer forests, active management would reduce crown fire potential but at the expense of timber stocks. When climate change was considered, however, trends in most ecosystem services changed substantially, with large increases in wildfire area predominating broad-scale trends in outputs, regardless of management approach (e.g., strong declines in timber stocks and habitat for closed-forest wildlife species). Active management still had an influence under a changing climate, but as a moderator of the strong climate-driven trends rather than being a principal driver of ecosystem service outputs. These results suggest projections of future ecosystem services that do not consider climate change may result in unrealistic expectations of benefits. Title: Divergent trends in ecosystem services under different climate-management futures in a fire-prone forest landscape Author: Halofsky, Joshua S., Halofsky, Jessica E., Hemstrom, Miles A., Morzillo, Anita T., Zhou, Xiaoping, Donato, Daniel C. Year: 2017 While ecosystem services and climate change are often examined independently, quantitative assessments integrating these fields are needed to inform future land management decisions. Using climate-informed state-and-transition simulations, we examined projected trends and trade-offs for a suite of ecosystem services under four climate change scenarios and two management scenarios (active management emphasizing fuel treatments and no management other than fire suppression) in a fire-prone landscape of dry and moist mixed-conifer forests in central Oregon, USA. Focal ecosystem services included fire potential (regulating service), timber volume (provisioning service), and potential wildlife habitat (supporting service). Projections without climate change suggested active management in dry mixed-conifer forests would create more open forest structures, reduce crown fire potential, and maintain timber stocks, while in moist mixed-conifer forests, active management would reduce crown fire potential but at the expense of timber stocks. When climate change was considered, however, trends in most ecosystem services changed substantially, with large increases in wildfire area predominating broad-scale trends in outputs, regardless of management approach (e.g., strong declines in timber stocks and habitat for closed-forest wildlife species). Active management still had an influence under a changing climate, but as a moderator of the strong climate-driven trends rather than being a principal driver of ecosystem service outputs. These results suggest projections of future ecosystem services that do not consider climate change may result in unrealistic expectations of benefits. Close

• 88. [Article] The analysis and use of methodologies for the study of the diets of long-eared owls from three environments in north central Oregon

  Part I of this study presents a procedure for standardization of pellet analysis methodologies which improves estimation of prey biomass and determines the number of pellets needed to estimate prey diversity ...

  Citation × Citation Citation Abstract Copy Title: The analysis and use of methodologies for the study of the diets of long-eared owls from three environments in north central Oregon Author: Barss, John M. Year: 1985 Part I of this study presents a procedure for standardization of pellet analysis methodologies which improves estimation of prey biomass and determines the number of pellets needed to estimate prey diversity indices. The procedure was developed to provide a simple, easily replicated methodology for the study of pellets which also retains maximal data recorded from pellet analysis. A sample size of ten Long-eared Owl pellets was found adequate to calculate diversity indices with no significant loss of accuracy when compared to total pellets recovered from beneath a roosting site. Analysis of the total sample of pellets from a specific roost provided information on intraspecies size selection by Long-eared Owls and also increased the probability of finding remains of rare prey in pellets from the areas studied. Part II of this study investigates the influences of seasonality and habitat differences on prey selection by Long-eared Owls in north-central Oregon. Differences in habitat where Long-eared Owls foraged were found to significantly influence prey species selection of Thomomys talpoides , Lagurus curtatus, Peromyscus maniculatus, Microtus montanus, and Perognathus parvus. Significant seasonal differences were also observed in the consumption of T. talpoides and M. montanus. Analysis of intraspecific size selection of northern pocket gophers by Long-eared Owls supports the observation that size of prey influences the foraging strategies of Long-eared Owls to a greater degree than does species composition. Title: The analysis and use of methodologies for the study of the diets of long-eared owls from three environments in north central Oregon Author: Barss, John M. Year: 1985 Part I of this study presents a procedure for standardization of pellet analysis methodologies which improves estimation of prey biomass and determines the number of pellets needed to estimate prey diversity indices. The procedure was developed to provide a simple, easily replicated methodology for the study of pellets which also retains maximal data recorded from pellet analysis. A sample size of ten Long-eared Owl pellets was found adequate to calculate diversity indices with no significant loss of accuracy when compared to total pellets recovered from beneath a roosting site. Analysis of the total sample of pellets from a specific roost provided information on intraspecies size selection by Long-eared Owls and also increased the probability of finding remains of rare prey in pellets from the areas studied. Part II of this study investigates the influences of seasonality and habitat differences on prey selection by Long-eared Owls in north-central Oregon. Differences in habitat where Long-eared Owls foraged were found to significantly influence prey species selection of Thomomys talpoides , Lagurus curtatus, Peromyscus maniculatus, Microtus montanus, and Perognathus parvus. Significant seasonal differences were also observed in the consumption of T. talpoides and M. montanus. Analysis of intraspecific size selection of northern pocket gophers by Long-eared Owls supports the observation that size of prey influences the foraging strategies of Long-eared Owls to a greater degree than does species composition. Close

• 89. [Article] The Effect of Artificial Light on Wildlife Use of a Passage Structure

  Barriers to animal movement can isolate populations, impacting their genetic diversity, susceptibility to disease, and access to resources. Barriers to movement may be caused by artificial light, which ...

  Citation × Citation Citation Abstract Copy Title: The Effect of Artificial Light on Wildlife Use of a Passage Structure Author: Bliss-Ketchum, Leslie, de Rivera, Catherine, Turner, Brian C., Weisbaum, Dolores Year: 2016 Barriers to animal movement can isolate populations, impacting their genetic diversity, susceptibility to disease, and access to resources. Barriers to movement may be caused by artificial light, which is known to disrupt bird, sea turtle, and bat behavior, but few studies have experimentally investigated the effects of artificial light on movement for a suite of terrestrial vertebrates. Therefore, we studied the effect of ecological light pollution on animal usage of a bridge under-road passage structure. On a weekly basis, sections of the structure were subjected to different light treatments including no light added, followed by a Reference period when lights were off in all the structure sections. Sand track data revealed use by 23 mammals, birds, reptiles and amphibians, nine of which had > 30 tracks for species-level analysis. Columbia black-tailed deer (Odocoileus hemionus columbianus) traversed under unlit bridge sections much less when neighboring sections were lit compared to when none were, suggesting avoidance due to any nearby presence of artificial light. Similarly, deer mouse (Peromyscus maniculatus) and opossum (Didelphis virginiana) track paths were less frequent in the lit sections than the ambient. Crossing was correlated with temporal or spatial factors but not light for three of the other species. These findings suggest that artificial light may be reducing habitat connectivity for some species though not providing a strong barrier for others. Such information is needed to inform mitigation of habitat fragmentation in the face of expanding urbanization. Title: The Effect of Artificial Light on Wildlife Use of a Passage Structure Author: Bliss-Ketchum, Leslie, de Rivera, Catherine, Turner, Brian C., Weisbaum, Dolores Year: 2016 Barriers to animal movement can isolate populations, impacting their genetic diversity, susceptibility to disease, and access to resources. Barriers to movement may be caused by artificial light, which is known to disrupt bird, sea turtle, and bat behavior, but few studies have experimentally investigated the effects of artificial light on movement for a suite of terrestrial vertebrates. Therefore, we studied the effect of ecological light pollution on animal usage of a bridge under-road passage structure. On a weekly basis, sections of the structure were subjected to different light treatments including no light added, followed by a Reference period when lights were off in all the structure sections. Sand track data revealed use by 23 mammals, birds, reptiles and amphibians, nine of which had > 30 tracks for species-level analysis. Columbia black-tailed deer (Odocoileus hemionus columbianus) traversed under unlit bridge sections much less when neighboring sections were lit compared to when none were, suggesting avoidance due to any nearby presence of artificial light. Similarly, deer mouse (Peromyscus maniculatus) and opossum (Didelphis virginiana) track paths were less frequent in the lit sections than the ambient. Crossing was correlated with temporal or spatial factors but not light for three of the other species. These findings suggest that artificial light may be reducing habitat connectivity for some species though not providing a strong barrier for others. Such information is needed to inform mitigation of habitat fragmentation in the face of expanding urbanization. Close

• 90. [Article] Advancing Collaborative Solutions: Lessons from the Oregon Sage-Grouse Conservation Partnership (SageCon)

  The Sage-Grouse Conservation Partnership, also known as “SageCon,” was an unprecedented collaborative effort among federal, state, and private stakeholders to address landscape-scale threats to greater ...

  Citation × Citation Citation Abstract Copy Title: Advancing Collaborative Solutions: Lessons from the Oregon Sage-Grouse Conservation Partnership (SageCon) Author: Allen, Jennifer H., Odell, Turner, Babcock, Julia, Henrie, Charis Year: 2017 The Sage-Grouse Conservation Partnership, also known as “SageCon,” was an unprecedented collaborative effort among federal, state, and private stakeholders to address landscape-scale threats to greater sage-grouse while also acknowledging rural economic and community interests across eastern Oregon’s sagebrush range. A U.S. Fish and Wildlife Service (USFWS) preliminary finding that the sage-grouse warranted listing under the endangered species act, and a subsequent court settlement setting a deadline for a final listing decision were key drivers for SageCon participants to seek proactive solutions to protect the bird. A cadre of diverse Eastern Oregon stakeholders with experience working collaboratively on related public lands issues helped set the stage for the collaborative effort. As part of what the Department of the Interior described as a historic outcome, SageCon produced the 2015 Oregon Sage-Grouse Action Plan, which details voluntary and state-regulated conservation measures to preserve habitat and protect Oregon’s sage-grouse population from threats on public and private land. SageCon—as one part of a broader multi-state collaborative effort—led to a subsequent USFWS finding that the sage-grouse no longer warranted listing as endangered. In our study of this collaborative effort, we interviewed seventeen SageCon participants to identify collaborative approaches that may offer promise for other conservation and public policy efforts. We explored participant motivation for engaging in the process, collaborative process design, integration of science into the SageCon deliberations, and other experiences that interviewees found relevant. Title: Advancing Collaborative Solutions: Lessons from the Oregon Sage-Grouse Conservation Partnership (SageCon) Author: Allen, Jennifer H., Odell, Turner, Babcock, Julia, Henrie, Charis Year: 2017 The Sage-Grouse Conservation Partnership, also known as “SageCon,” was an unprecedented collaborative effort among federal, state, and private stakeholders to address landscape-scale threats to greater sage-grouse while also acknowledging rural economic and community interests across eastern Oregon’s sagebrush range. A U.S. Fish and Wildlife Service (USFWS) preliminary finding that the sage-grouse warranted listing under the endangered species act, and a subsequent court settlement setting a deadline for a final listing decision were key drivers for SageCon participants to seek proactive solutions to protect the bird. A cadre of diverse Eastern Oregon stakeholders with experience working collaboratively on related public lands issues helped set the stage for the collaborative effort. As part of what the Department of the Interior described as a historic outcome, SageCon produced the 2015 Oregon Sage-Grouse Action Plan, which details voluntary and state-regulated conservation measures to preserve habitat and protect Oregon’s sage-grouse population from threats on public and private land. SageCon—as one part of a broader multi-state collaborative effort—led to a subsequent USFWS finding that the sage-grouse no longer warranted listing as endangered. In our study of this collaborative effort, we interviewed seventeen SageCon participants to identify collaborative approaches that may offer promise for other conservation and public policy efforts. We explored participant motivation for engaging in the process, collaborative process design, integration of science into the SageCon deliberations, and other experiences that interviewees found relevant. Close