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• 1. [Article] Gwinnett County Parks and Recreation - Invasive Plant Species Management Plan

  2016

  Citation × Citation Citation Abstract Copy Title: Gwinnett County Parks and Recreation - Invasive Plant Species Management Plan Author: Patterson, Mark Andre 2016 Title: Gwinnett County Parks and Recreation - Invasive Plant Species Management Plan Author: Patterson, Mark Andre 2016 Close

• 2. [Article] Bio-Economic Modelling of the Red King Crab Invasion in the Barents Sea

  Abstract only.

  Citation × Citation Citation Abstract Copy Title: Bio-Economic Modelling of the Red King Crab Invasion in the Barents Sea Author: Armstrong, Claire, Falk-Petersen, Jannike Abstract only. Title: Bio-Economic Modelling of the Red King Crab Invasion in the Barents Sea Author: Armstrong, Claire, Falk-Petersen, Jannike Abstract only. Close

• 3. [Article] Resilience to Stress and Disturbance, and Resistance to Bromus tectorum L. Invasion in Cold Desert Shrublands of Western North America

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

  Citation × Citation Citation Abstract Copy Title: Resilience to Stress and Disturbance, and Resistance to Bromus tectorum L. Invasion in Cold Desert Shrublands of Western North America Author: Miller, Richard F., Germino, Matthew J., Grace, James B., D'Antonio, Carla, Brown, Cynthia S., Bradley, Bethany A., Hardegree, Stuart P., Pyke, David A., Chambers, Jeanne C. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Springer and can be found at: http://link.springer.com/journal/10021. Title: Resilience to Stress and Disturbance, and Resistance to Bromus tectorum L. Invasion in Cold Desert Shrublands of Western North America Author: Miller, Richard F., Germino, Matthew J., Grace, James B., D'Antonio, Carla, Brown, Cynthia S., Bradley, Bethany A., Hardegree, Stuart P., Pyke, David A., Chambers, Jeanne C. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Springer and can be found at: http://link.springer.com/journal/10021. Close

• 4. [Article] Recommendations for Control of Tall Oatgrass, Poison Oak, and Rose in Willamette Valley Upland Prairies

  Native upland prairies, which once dominated the landscape of the Willamette Valley, are considered among the rarest of Oregon's ecosystems. Even though only remnants remain today, they harbor many rare ...

  Citation × Citation Citation Abstract Copy Title: Recommendations for Control of Tall Oatgrass, Poison Oak, and Rose in Willamette Valley Upland Prairies Author: Wilson, Mark V., Clark, Deborah Louise, 1950- Native upland prairies, which once dominated the landscape of the Willamette Valley, are considered among the rarest of Oregon's ecosystems. Even though only remnants remain today, they harbor many rare and endangered species such as the Fender's blue butterfly and its host plant, Kincaid’s lupine. Invasion of remnant prairies by woody plants and weedy non-native herbaceous species is of great concern to agencies and managers responsible for conserving these native ecosystems. Available methods for the control of these pests include herbicides, biological control, prescribed burning, and mowing. This report first reviews the literature on the control of tall oatgrass and the shrubs poison oak and rose. Each of these species is an important threat to Willamette Valley upland prairies. We then presents recommendations. For control of tall oatgrass, we recommend for most situations mowing in late spring or early summer. Mowing height should be just above most of the foliage of native plants to be protected (typically 10 cm - 15 cm). In areas with Kincaid’s lupine and Fender’s blue butterfly, mowing should be delayed until July, after the flowering and flight seasons. For control of prairie shrubs, we recommend further studies to evaluate herbicide effectiveness against the target shrubs and safety for non-target native plants and animals. If herbicide use is unavailable, we recommend burning or mowing. All burning or mowing treatments should be repeated, perhaps indefinitely, to maintain pest plant control. Title: Recommendations for Control of Tall Oatgrass, Poison Oak, and Rose in Willamette Valley Upland Prairies Author: Wilson, Mark V., Clark, Deborah Louise, 1950- Native upland prairies, which once dominated the landscape of the Willamette Valley, are considered among the rarest of Oregon's ecosystems. Even though only remnants remain today, they harbor many rare and endangered species such as the Fender's blue butterfly and its host plant, Kincaid’s lupine. Invasion of remnant prairies by woody plants and weedy non-native herbaceous species is of great concern to agencies and managers responsible for conserving these native ecosystems. Available methods for the control of these pests include herbicides, biological control, prescribed burning, and mowing. This report first reviews the literature on the control of tall oatgrass and the shrubs poison oak and rose. Each of these species is an important threat to Willamette Valley upland prairies. We then presents recommendations. For control of tall oatgrass, we recommend for most situations mowing in late spring or early summer. Mowing height should be just above most of the foliage of native plants to be protected (typically 10 cm - 15 cm). In areas with Kincaid’s lupine and Fender’s blue butterfly, mowing should be delayed until July, after the flowering and flight seasons. For control of prairie shrubs, we recommend further studies to evaluate herbicide effectiveness against the target shrubs and safety for non-target native plants and animals. If herbicide use is unavailable, we recommend burning or mowing. All burning or mowing treatments should be repeated, perhaps indefinitely, to maintain pest plant control. Close

• 5. [Article] Willamette Valley prairie restoration : the Native Seed Network and Sidalcea

  My internship was conducted with the Native Seed Network program within the Institute for Applied Ecology, a non-profit organization located in Corvallis, whose focus is education, applied research and ...

  Citation × Citation Citation Abstract Copy Title: Willamette Valley prairie restoration : the Native Seed Network and Sidalcea Author: Lambert, Joshua K. My internship was conducted with the Native Seed Network program within the Institute for Applied Ecology, a non-profit organization located in Corvallis, whose focus is education, applied research and active restoration and of native ecosystems. My internship goals were to increase my experience in applied restoration ecology and conservation biology with the emphasis on native plant communities in particular the endangered prairie communities of the Willamette Valley. These goals were met through my tenure with the Native Seed Network’s native seed collection and increase program during the 2007 field season. This work provided me strong experience with a process necessary for genetically conservative restoration and provided the NSN with a willing intern to complete their goals for 2007. Additional work I accomplished included a morphometric analysis of the native Willamette Valley prairie forb Sidalcea campestris which served as one constituent towards resolving the general ambiguity of this focal species for prairie restoration. Included in this analysis is a presentation and my interpretation of an initial molecular phylogenetic analysis on a selection of S. campestris accessions by Liston and deFeniks (unpublished) that may aid in the future resolution of S. campestris and other congeners in the Willamette Valley. The purpose of the morphological research was not mastery of population genetics or statistics but an exercise in concentration and achievement towards a more integrated and advanced application of taxonomic work oriented towards preserving biological diversity. This entire report completes the written requirement for the Professional Science Masters degree in Applied Systematic through the Botany and Plant Pathology Department at Oregon State University. Title: Willamette Valley prairie restoration : the Native Seed Network and Sidalcea Author: Lambert, Joshua K. My internship was conducted with the Native Seed Network program within the Institute for Applied Ecology, a non-profit organization located in Corvallis, whose focus is education, applied research and active restoration and of native ecosystems. My internship goals were to increase my experience in applied restoration ecology and conservation biology with the emphasis on native plant communities in particular the endangered prairie communities of the Willamette Valley. These goals were met through my tenure with the Native Seed Network’s native seed collection and increase program during the 2007 field season. This work provided me strong experience with a process necessary for genetically conservative restoration and provided the NSN with a willing intern to complete their goals for 2007. Additional work I accomplished included a morphometric analysis of the native Willamette Valley prairie forb Sidalcea campestris which served as one constituent towards resolving the general ambiguity of this focal species for prairie restoration. Included in this analysis is a presentation and my interpretation of an initial molecular phylogenetic analysis on a selection of S. campestris accessions by Liston and deFeniks (unpublished) that may aid in the future resolution of S. campestris and other congeners in the Willamette Valley. The purpose of the morphological research was not mastery of population genetics or statistics but an exercise in concentration and achievement towards a more integrated and advanced application of taxonomic work oriented towards preserving biological diversity. This entire report completes the written requirement for the Professional Science Masters degree in Applied Systematic through the Botany and Plant Pathology Department at Oregon State University. Close

• 6. [Article] Food systems in the Marys River region and reinhabitation

  Reinhabitation is an approach to building local cultures and economies within industrial society. The food system is a vital starting point. What are the principles of reinhabitory food systems? What are ...

  Citation × Citation Citation Abstract Copy Title: Food systems in the Marys River region and reinhabitation Author: Burke, Erik P. Reinhabitation is an approach to building local cultures and economies within industrial society. The food system is a vital starting point. What are the principles of reinhabitory food systems? What are the possibilities for a locally adapted food system in the Marys River region of western Oregon? I describe past and present food systems in the region and give recommendations for building a reinhabitory food system. Native people established locally adapted food systems in the Marys River region and maintained them for thousands of years, culminating in the Kalapuyan food system that existed at Euroamerican contact. Euroamericans began to settle in the region in 1845, and immediately began to domesticate the landscape, replacing native ecosystems with cropland and pasture. By 1900, a diversified food system had emerged with several locally adapted characteristics. The industrial food system replaced the diversified food system during World War II, and has dominated since then. Locally adapted elements of food systems were rapidly abandoned. Industrialism emphasized mass production of export crops using fossil fuels, heavy machinery, and agrichemicals. A large variety of cultural, economic, and ecological problems emerged, and the health of natural and human communities was diminished. Reinhabitation is a positive response to the problems of industrial food systems. A locally adapted food system in the Marys River region is possible. There is enough agricultural land to feed the population. A small but growing segment of the local population has established alternative food systems, and initiated the process of building a regional food system. Reviewing the history of the Marys River region helps clarify how to apply principles of reinhabitation in the region. Title: Food systems in the Marys River region and reinhabitation Author: Burke, Erik P. Reinhabitation is an approach to building local cultures and economies within industrial society. The food system is a vital starting point. What are the principles of reinhabitory food systems? What are the possibilities for a locally adapted food system in the Marys River region of western Oregon? I describe past and present food systems in the region and give recommendations for building a reinhabitory food system. Native people established locally adapted food systems in the Marys River region and maintained them for thousands of years, culminating in the Kalapuyan food system that existed at Euroamerican contact. Euroamericans began to settle in the region in 1845, and immediately began to domesticate the landscape, replacing native ecosystems with cropland and pasture. By 1900, a diversified food system had emerged with several locally adapted characteristics. The industrial food system replaced the diversified food system during World War II, and has dominated since then. Locally adapted elements of food systems were rapidly abandoned. Industrialism emphasized mass production of export crops using fossil fuels, heavy machinery, and agrichemicals. A large variety of cultural, economic, and ecological problems emerged, and the health of natural and human communities was diminished. Reinhabitation is a positive response to the problems of industrial food systems. A locally adapted food system in the Marys River region is possible. There is enough agricultural land to feed the population. A small but growing segment of the local population has established alternative food systems, and initiated the process of building a regional food system. Reviewing the history of the Marys River region helps clarify how to apply principles of reinhabitation in the region. Close

• 7. [Article] Linking removal targets to the ecological effects of invaders: a predictive model and field test

  Species invasions have a range of negative effects on recipient ecosystems, and many occur at a scale and magnitude that preclude complete eradication. When complete extirpation is unlikely with available ...

  Citation × Citation Citation Abstract Copy Title: Linking removal targets to the ecological effects of invaders: a predictive model and field test Author: Brooks, Annabelle L. M., Côté, Isabelle M., Miller, Skylar, Green, Stephanie J., Dulvy, Nicholas K., Cooper, Andrew B., Akins, John L. Species invasions have a range of negative effects on recipient ecosystems, and many occur at a scale and magnitude that preclude complete eradication. When complete extirpation is unlikely with available management resources, an effective strategy may be to suppress invasive populations below levels predicted to cause undesirable ecological change. We illustrate this approach by developing and testing targets for the control of invasive Indo-Pacific lionfish (Pterois volitans and P. miles) on Western Atlantic coral reefs. We first developed a size structured simulation model of predation by lionfish on native fish communities, which we used to predict threshold densities of lionfish beyond which native fish biomass should decline. We then tested our predictions by experimentally manipulating lionfish densities above or below reef-specific thresholds, and monitoring the consequences for native fish populations on 24 Bahamian patch reefs over 18 months. We found that reducing lionfish below predicted threshold densities effectively protected native fish community biomass from predation-induced declines. Reductions in density of 75- 95%, depending on the reef, were required to suppress lionfish below levels predicted to over-consume prey. On reefs where lionfish were kept threshold densities, native prey fish biomass increased by 50-70%. Gains in small (<6cm) size classes of native fishes translated into lagged increases in larger size classes over time. The biomass of larger individuals (>15cm total length), including ecologically important grazers and economically important fisheries species, had increased by 10-65% by the end of the experiment. Crucially, similar gains in prey fish biomass were realized on reefs subjected to partial and full removal of lionfish, but partial removals took 30% less time to implement. By contrast, the biomass of small native fishes declined by more than 50% on all reefs with lionfish densities exceeding reef-specific thresholds. Large inter-reef variation in the biomass of prey fishes at the outset of the study, which influences the threshold density of lionfish, means that we identify a single rule-of-thumb for guiding control efforts. However, our model provides a method for setting reef-specific targets for population control using local monitoring data. Our work is the first to demonstrate that for ongoing invasions, suppressing invaders below densitiesterms of protecting the native ecosystem on a local scale, to achieving complete eradication Title: Linking removal targets to the ecological effects of invaders: a predictive model and field test Author: Brooks, Annabelle L. M., Côté, Isabelle M., Miller, Skylar, Green, Stephanie J., Dulvy, Nicholas K., Cooper, Andrew B., Akins, John L. Species invasions have a range of negative effects on recipient ecosystems, and many occur at a scale and magnitude that preclude complete eradication. When complete extirpation is unlikely with available management resources, an effective strategy may be to suppress invasive populations below levels predicted to cause undesirable ecological change. We illustrate this approach by developing and testing targets for the control of invasive Indo-Pacific lionfish (Pterois volitans and P. miles) on Western Atlantic coral reefs. We first developed a size structured simulation model of predation by lionfish on native fish communities, which we used to predict threshold densities of lionfish beyond which native fish biomass should decline. We then tested our predictions by experimentally manipulating lionfish densities above or below reef-specific thresholds, and monitoring the consequences for native fish populations on 24 Bahamian patch reefs over 18 months. We found that reducing lionfish below predicted threshold densities effectively protected native fish community biomass from predation-induced declines. Reductions in density of 75- 95%, depending on the reef, were required to suppress lionfish below levels predicted to over-consume prey. On reefs where lionfish were kept threshold densities, native prey fish biomass increased by 50-70%. Gains in small (<6cm) size classes of native fishes translated into lagged increases in larger size classes over time. The biomass of larger individuals (>15cm total length), including ecologically important grazers and economically important fisheries species, had increased by 10-65% by the end of the experiment. Crucially, similar gains in prey fish biomass were realized on reefs subjected to partial and full removal of lionfish, but partial removals took 30% less time to implement. By contrast, the biomass of small native fishes declined by more than 50% on all reefs with lionfish densities exceeding reef-specific thresholds. Large inter-reef variation in the biomass of prey fishes at the outset of the study, which influences the threshold density of lionfish, means that we identify a single rule-of-thumb for guiding control efforts. However, our model provides a method for setting reef-specific targets for population control using local monitoring data. Our work is the first to demonstrate that for ongoing invasions, suppressing invaders below densitiesterms of protecting the native ecosystem on a local scale, to achieving complete eradication Close

• 8. [Article] Foraging in disturbed areas : a study of sweat bees (Hymenoptera: Halictidae) in Oregon

  Bees provide vital ecosystem services for cropping systems as well as natural landscapes. Declines in both both native bee and managed honey bee (Apis mellifera L.) populations has brought attention to ...

  Citation × Citation Citation Abstract Copy Title: Foraging in disturbed areas : a study of sweat bees (Hymenoptera: Halictidae) in Oregon Author: Broussard, Melissa Bees provide vital ecosystem services for cropping systems as well as natural landscapes. Declines in both both native bee and managed honey bee (Apis mellifera L.) populations has brought attention to the significance of their role as pollinators in managed and native ecosystems. As a result, conservation efforts have been undertaken to preserve them. While considerable attention has been given to honey bees, relatively little is known about many native bee species. Of particular interest is the family Halictidae, which can comprise the majority of observed individuals in many habitats. These, often small, bees are difficult to identify, and, as a result, relatively little is known about their preferred floral hosts. Because bee species assemblages vary significantly from region to region, it is important to have an understanding of local populations and their floral hosts. It is also important to understand factors which affect the quantity and quality of floral resources, such as anthropogenic disturbance. The Pacific Northwest is a diverse landscape, with rich agricultural and wildland environments that require pollinators in order to continue to thrive. Two studies examine the interface between these two systems, the first explores how roadside disturbance, which is prevalent across the world, impacts native pollinators across habitat types, and the second explores the diet of common native species, and how that diet changes across habitat types. In these studies, it was found that roadside disturbance was associated with reduced native bee diversity and abundance in the seasonally wet Willamette Valley of Oregon, but not in the more xeric Central Oregon. Bee abundance was positively correlated with temperature. Bee diet was more diverse in areas of scarce floral resources. In both regions, exotic plants were important floral hosts, representing nearly half of observed floral visitations. This thesis presents results of species analysis, floral richness and density correlations, and comparisons of floral resources used by different bee species. Implications and recommendations for land management are discussed. Title: Foraging in disturbed areas : a study of sweat bees (Hymenoptera: Halictidae) in Oregon Author: Broussard, Melissa Bees provide vital ecosystem services for cropping systems as well as natural landscapes. Declines in both both native bee and managed honey bee (Apis mellifera L.) populations has brought attention to the significance of their role as pollinators in managed and native ecosystems. As a result, conservation efforts have been undertaken to preserve them. While considerable attention has been given to honey bees, relatively little is known about many native bee species. Of particular interest is the family Halictidae, which can comprise the majority of observed individuals in many habitats. These, often small, bees are difficult to identify, and, as a result, relatively little is known about their preferred floral hosts. Because bee species assemblages vary significantly from region to region, it is important to have an understanding of local populations and their floral hosts. It is also important to understand factors which affect the quantity and quality of floral resources, such as anthropogenic disturbance. The Pacific Northwest is a diverse landscape, with rich agricultural and wildland environments that require pollinators in order to continue to thrive. Two studies examine the interface between these two systems, the first explores how roadside disturbance, which is prevalent across the world, impacts native pollinators across habitat types, and the second explores the diet of common native species, and how that diet changes across habitat types. In these studies, it was found that roadside disturbance was associated with reduced native bee diversity and abundance in the seasonally wet Willamette Valley of Oregon, but not in the more xeric Central Oregon. Bee abundance was positively correlated with temperature. Bee diet was more diverse in areas of scarce floral resources. In both regions, exotic plants were important floral hosts, representing nearly half of observed floral visitations. This thesis presents results of species analysis, floral richness and density correlations, and comparisons of floral resources used by different bee species. Implications and recommendations for land management are discussed. Close

• 9. [Article] Conservation of Sidalcea nelsoniana through habitat management : effects of burning, mowing, and altered flooding regime on a rare Willamette Valley perennial

  Active habitat management plays a key role in the preservation of native ecosystems and rare species, especially in the Willamette Valley of Oregon, where natural succession to woodlands threatens the ...

  Citation × Citation Citation Abstract Copy Title: Conservation of Sidalcea nelsoniana through habitat management : effects of burning, mowing, and altered flooding regime on a rare Willamette Valley perennial Author: Bartels, Marilynn R. Active habitat management plays a key role in the preservation of native ecosystems and rare species, especially in the Willamette Valley of Oregon, where natural succession to woodlands threatens the few wetland prairies remaining after 150 years of agriculture and urbanization. Sidalcea nelsoniana, listed as threatened under the federal Endangered Species Act, is native to these wetland prairies. The studies described here provide basic information about the habitat requirements and tolerances of S. nelsoniana while testing for the first time the impact of specific management techniques on its growth and reproduction. The effects of prescribed burning and mowing on S. nelsoniana and its habitat were investigated in a field population at W.L. Finley National Wildlife Refuge near Corvallis, Oregon. Measurements of S. nelsoniana and aspects of the surrounding vegetation were recorded during the summer of 1998 within 112 permanent S. nelsoniana-centered quadrats. Burning and mowing treatments were applied in the fall of 1998 and the same measurements of S. nelsoniana and the surrounding vegetation were recorded during the summer of 1999. Treatments had no direct effects on S. nelsoniana performance, but burning and mowing reduced canopy cover, a primary goal of prairie maintenance and restoration. Because perennials often respond slowly to changes in habitat, effects of these manipulations may be more evident in future years. Wetland species may also be sensitive to site hydrology, so maintaining the proper water regime is another important component of wetland prairie management and restoration. A second experimental study evaluated the flooding tolerance of S. nelsoniana. Rhizome fragments were transplanted into pots exposed to four flooding conditions: drained soil, saturated soil with no standing water, standing water from mid-November through mid-April and standing water from mid-November through mid-June. Plants with drained soil died as the spring rains declined, and plants flooded past April died by mid-June. Plants in saturated soils and those flooded until mid-April were most successful. These two treatments most closely match conditions found in Willamette Valley wetland prairies, including S. nelsoniana sites, and suggest that the current distribution of S. nelsoniana approximately matches its hydrologic requirements. Management plans to flood a S. nelsoniana site beyond mid-April might harm this protected species. Title: Conservation of Sidalcea nelsoniana through habitat management : effects of burning, mowing, and altered flooding regime on a rare Willamette Valley perennial Author: Bartels, Marilynn R. Active habitat management plays a key role in the preservation of native ecosystems and rare species, especially in the Willamette Valley of Oregon, where natural succession to woodlands threatens the few wetland prairies remaining after 150 years of agriculture and urbanization. Sidalcea nelsoniana, listed as threatened under the federal Endangered Species Act, is native to these wetland prairies. The studies described here provide basic information about the habitat requirements and tolerances of S. nelsoniana while testing for the first time the impact of specific management techniques on its growth and reproduction. The effects of prescribed burning and mowing on S. nelsoniana and its habitat were investigated in a field population at W.L. Finley National Wildlife Refuge near Corvallis, Oregon. Measurements of S. nelsoniana and aspects of the surrounding vegetation were recorded during the summer of 1998 within 112 permanent S. nelsoniana-centered quadrats. Burning and mowing treatments were applied in the fall of 1998 and the same measurements of S. nelsoniana and the surrounding vegetation were recorded during the summer of 1999. Treatments had no direct effects on S. nelsoniana performance, but burning and mowing reduced canopy cover, a primary goal of prairie maintenance and restoration. Because perennials often respond slowly to changes in habitat, effects of these manipulations may be more evident in future years. Wetland species may also be sensitive to site hydrology, so maintaining the proper water regime is another important component of wetland prairie management and restoration. A second experimental study evaluated the flooding tolerance of S. nelsoniana. Rhizome fragments were transplanted into pots exposed to four flooding conditions: drained soil, saturated soil with no standing water, standing water from mid-November through mid-April and standing water from mid-November through mid-June. Plants with drained soil died as the spring rains declined, and plants flooded past April died by mid-June. Plants in saturated soils and those flooded until mid-April were most successful. These two treatments most closely match conditions found in Willamette Valley wetland prairies, including S. nelsoniana sites, and suggest that the current distribution of S. nelsoniana approximately matches its hydrologic requirements. Management plans to flood a S. nelsoniana site beyond mid-April might harm this protected species. Close

• 10. [Article] Landsat-based monitoring of annual wetland change in the main-stem Willamette River floodplain of Oregon, USA from 1972 to 2012

  Despite holding substantial ecological value, wetlands in the United States have experienced a significant decline in both area and function over the past century with the majority of freshwater wetland ...

  Citation × Citation Citation Abstract Copy Title: Landsat-based monitoring of annual wetland change in the main-stem Willamette River floodplain of Oregon, USA from 1972 to 2012 Author: Fickas, Kate, Colleen Despite holding substantial ecological value, wetlands in the United States have experienced a significant decline in both area and function over the past century with the majority of freshwater wetland loss attributed to agricultural conversion. Agriculture is the second largest industry in the State of Oregon and the State places substantial emphasis in its land use planning goals on the preservation of agricultural land. Oregon’s Willamette Valley accounts for the majority of agricultural output with 53% of the valley bottom classified as agricultural land. Additionally, the valley houses 70% of the state's population. The valley was once comprised of extensive wet prairies and abundant riparian forests along the Willamette River floodplain, but native ecosystems have been reduced to a fraction of their original distribution since Euro-American settlement in the mid 1800s. The few wetlands that remain are at high risk to loss and degradation from agricultural activity. Following national wetland conservation policies, Oregon has since attempted to monitor and regulate losses due to disturbance and modification of the State's remaining wetlands through a "no-net-loss" policy aiming to decrease wetland losses and replace disturbed wetlands through mitigation. The National Wetlands Inventory (NWI) was designed to produce detailed maps and status reports of the characteristics and extent of the nation's wetlands and help determine the efficacy of no-net-loss policy implementation on the nation’s wetlands. In some cases, the NWI has been found to have low categorical and spatial accuracy and coarse temporal resolution, with some maps over two decades old. Although Landsat satellite imagery was originally found to lack the needed spatial resolution for classification detail and wetness designation that aerial photography provided, Landsat has 40 years of freely available, high quality annual imagery and should be explored for use in annual wetland change detection. Our objectives were to: (1) Quantify and characterize spatial and ecological trends in annual wetland change through gain, loss, and conversion in the Willamette Valley; (2) Evaluate the effect of the no-net-loss federal wetland conservation policy change enacted in 1990 on trends in net wetland area; and (3) Describe a new methodology that reaches back through the over 40-year Landsat archive to map fine scale wetland and related land-use changes from 1972-2012. We used annual Landsat MSS and TM/ETM+ images from 1972 to 2012 to manually interpret loss, gain, and type conversion of wetland area in the two-year inundation floodplain of the Main-Stem Willamette River using TimeSync, Google Earth, and ArcMap. By creating Tasseled Cap Brightness, Greenness, and Wetness indices for MSS data that visually match TM/ETM+ Tasseled Cap images, we were able to construct a complete and consistent annual time series and utilize the entire Landsat archive. Additionally, with an extended time series, we were able to compare trends of annual net change in wetland area before and after the no-net-loss policy established under Section 404 of the Clean Water Act in 1990. We found that wetlands experienced annual loss, gain, and type conversion across the entire study period. Vegetated wetlands (emergent and riparian wetlands) experienced a 314 ha net loss of wetland area across the 40 year study period whereas non-vegetated wetlands (lacustrine and riverine wetlands) experienced a 393 ha net gain. All wetland types combined saw a 79 ha net increase in wetland area across the full study period. The majority of both gain and loss in the study area was attributed to and from agricultural conversion followed by urban land use. Time series analysis of the rate of change of net wetland area was calculated using the Theil-Sen (TS) Slope estimate analysis. For annual change of wetland area before and after 1990 no-net-loss policy implementations, the rate of annual wetland area lost slowed for riparian wetlands and reversed into trends of annual net gain in area of emergent wetlands. The rate of annual net area gained for lacustrine wetlands was slowed post-policy. Accuracy assessment of land use change polygons in the field was only able to capture 12% of our interpretations due to access restrictions associated with private land. In spite of a low sample size (n=45), overall accuracy of land use classification through wetland change polygons was at 80%. This accuracy increased to 91.1% when land use classes were aggregated to either wetland or upland categories, indicating that our methodology was more accurate at distinguishing between general upland and wetland than finer categorical classes. Title: Landsat-based monitoring of annual wetland change in the main-stem Willamette River floodplain of Oregon, USA from 1972 to 2012 Author: Fickas, Kate, Colleen Despite holding substantial ecological value, wetlands in the United States have experienced a significant decline in both area and function over the past century with the majority of freshwater wetland loss attributed to agricultural conversion. Agriculture is the second largest industry in the State of Oregon and the State places substantial emphasis in its land use planning goals on the preservation of agricultural land. Oregon’s Willamette Valley accounts for the majority of agricultural output with 53% of the valley bottom classified as agricultural land. Additionally, the valley houses 70% of the state's population. The valley was once comprised of extensive wet prairies and abundant riparian forests along the Willamette River floodplain, but native ecosystems have been reduced to a fraction of their original distribution since Euro-American settlement in the mid 1800s. The few wetlands that remain are at high risk to loss and degradation from agricultural activity. Following national wetland conservation policies, Oregon has since attempted to monitor and regulate losses due to disturbance and modification of the State's remaining wetlands through a "no-net-loss" policy aiming to decrease wetland losses and replace disturbed wetlands through mitigation. The National Wetlands Inventory (NWI) was designed to produce detailed maps and status reports of the characteristics and extent of the nation's wetlands and help determine the efficacy of no-net-loss policy implementation on the nation’s wetlands. In some cases, the NWI has been found to have low categorical and spatial accuracy and coarse temporal resolution, with some maps over two decades old. Although Landsat satellite imagery was originally found to lack the needed spatial resolution for classification detail and wetness designation that aerial photography provided, Landsat has 40 years of freely available, high quality annual imagery and should be explored for use in annual wetland change detection. Our objectives were to: (1) Quantify and characterize spatial and ecological trends in annual wetland change through gain, loss, and conversion in the Willamette Valley; (2) Evaluate the effect of the no-net-loss federal wetland conservation policy change enacted in 1990 on trends in net wetland area; and (3) Describe a new methodology that reaches back through the over 40-year Landsat archive to map fine scale wetland and related land-use changes from 1972-2012. We used annual Landsat MSS and TM/ETM+ images from 1972 to 2012 to manually interpret loss, gain, and type conversion of wetland area in the two-year inundation floodplain of the Main-Stem Willamette River using TimeSync, Google Earth, and ArcMap. By creating Tasseled Cap Brightness, Greenness, and Wetness indices for MSS data that visually match TM/ETM+ Tasseled Cap images, we were able to construct a complete and consistent annual time series and utilize the entire Landsat archive. Additionally, with an extended time series, we were able to compare trends of annual net change in wetland area before and after the no-net-loss policy established under Section 404 of the Clean Water Act in 1990. We found that wetlands experienced annual loss, gain, and type conversion across the entire study period. Vegetated wetlands (emergent and riparian wetlands) experienced a 314 ha net loss of wetland area across the 40 year study period whereas non-vegetated wetlands (lacustrine and riverine wetlands) experienced a 393 ha net gain. All wetland types combined saw a 79 ha net increase in wetland area across the full study period. The majority of both gain and loss in the study area was attributed to and from agricultural conversion followed by urban land use. Time series analysis of the rate of change of net wetland area was calculated using the Theil-Sen (TS) Slope estimate analysis. For annual change of wetland area before and after 1990 no-net-loss policy implementations, the rate of annual wetland area lost slowed for riparian wetlands and reversed into trends of annual net gain in area of emergent wetlands. The rate of annual net area gained for lacustrine wetlands was slowed post-policy. Accuracy assessment of land use change polygons in the field was only able to capture 12% of our interpretations due to access restrictions associated with private land. In spite of a low sample size (n=45), overall accuracy of land use classification through wetland change polygons was at 80%. This accuracy increased to 91.1% when land use classes were aggregated to either wetland or upland categories, indicating that our methodology was more accurate at distinguishing between general upland and wetland than finer categorical classes. Close

• 11. [Article] Effects of the invasive Pacific red lionfish Pterois volitans on native Atlantic coral-reef fish communities

  Predatory lionfishes (Pterois volitans and P. miles) were introduced to Florida waters during the mid to late 1980s, and eventually established self-sustaining breeding populations in the tropical western ...

  Citation × Citation Citation Abstract Copy Title: Effects of the invasive Pacific red lionfish Pterois volitans on native Atlantic coral-reef fish communities Author: Albins, Mark A. Predatory lionfishes (Pterois volitans and P. miles) were introduced to Florida waters during the mid to late 1980s, and eventually established self-sustaining breeding populations in the tropical western Atlantic. These invasive species are now widespread along the southeastern seaboard of the United States, across the Caribbean Sea, and in the Gulf of Mexico. In these regions, lionfish reach larger maximum sizes and higher abundances than they do in their native Pacific, suggesting that they have undergone ecological release. Invaded marine communities have thus far provided little if any biotic resistance. Lionfish are generalist predators with high consumption rates, inhabit a broad range of habitats, are defended from predation by venomous spines, and are capable of long-range larval dispersal. It is possible that lionfish have direct effects on native communities, through consumption of native fishes and competition with native predators, as well as indirect effects, such as overconsumption of herbivorous fishes that prevent seaweeds from outcompeting reef-building corals. There is also serious concern that invasive lionfish could act additively, or even synergistically, with existing stressors of coral-reef systems, such as overfishing and ocean warming, resulting in substantial negative consequences for native ecosystems and economically valuable fisheries. The primary goal of this dissertation was to conduct a set of controlled, replicated field experiments to rigorously examine and measure the effects of lionfish on native reef-fish communities across a range of spatial and temporal scales. In the first experiment (Chapter 2), the net recruitment of native fishes to twenty small patch reefs was compared in the presence (n = 10) and absence (n = 10) of lionfish. This study demonstrated that lionfish reduced net recruitment, or change in abundance of small native fishes, by an average (± SEM) of 78.9 ± 32.2 % over 5 weeks, affecting 23 of 38 species recruiting to reefs in both treatments. In a second experiment (Chapter 4), I examined the effects of lionfish on patch-reef communities of small native fishes relative to, and in combination with, those of a similarly sized native predator, the coney grouper (Cephalopholis fulva). Four different predator treatments were established by transplanting predators (n = 5 reefs each). Treatments included a single small invasive lionfish, a single small native grouper, a grouper and a lionfish together, and predator-free controls. Compared to controls, invasive lionfish caused reductions (mean ± SEM) in abundance (93.7 ± 17.8 %) and species richness (4.6 ± 1.6 species) of small native fishes. The negative effect of lionfish on abundance was 2.6 ± 0.5 times stronger than that of the native grouper. The greatest negative effects on abundance, species richness, evenness, and diversity of native fishes occurred when both lionfish and native grouper were present. Additionally, lionfish grew more than six times faster in both length and mass than did native grouper. A third experiment (Chapter 6) assessed the effects of lionfish on native reef-fish communities at spatial and temporal scales directly relevant to management and conservation efforts. Subsequent to baseline surveys, high- and low-density lionfish treatments were established on 10 large (1400 to 4000 m²) isolated coral reefs. After initiation of treatments, quarterly surveys of the native reef-fish communities were conducted for approximately 14 months. Lionfish caused significant reductions (mean ± SEM) in density (up to 3.22 ± 0.95 fish m⁻²), biomass (3.26 ± 1.10 g m⁻²), and species richness (4.92 ± 2.09 species) of small (<10 cm TL) native fishes. However, these negative effects on prey-sized fishes had not yet translated into declines in larger size classes during the first 14 months of this experiment. In addition to field experiments, this dissertation describes field and aquarium observations of a previously undocumented piscivorous behavior by invasive lionfish - blowing jets of water at prey fish - which may confer a high degree of predation efficiency, thus contributing to the dramatic success of the invasion (Chapter 5). Also provided is a review of the current state of knowledge about the lionfish invasion, with speculation on the long-term effects of the invasion on coral-reef communities, and a brief discussion of potential mitigation measures (Chapter 3). In sum, this research demonstrated that invasive lionfish have substantial negative effects on native communities of coral-reef fishes. In all cases, numerical reductions in small (prey-sized) native fishes caused by lionfish were substantial. Additionally, lionfish caused considerable reductions in native reef-fish species richness (via predation on rare species). These findings indicate that the lionfish invasion may have long-term, broad-scale impacts on the structure and function of coral-reef communities as a whole, potentially reducing the resilience of these systems to a myriad of existing stressors as well as their capacity to provide valuable ecosystem goods and services to humans. Title: Effects of the invasive Pacific red lionfish Pterois volitans on native Atlantic coral-reef fish communities Author: Albins, Mark A. Predatory lionfishes (Pterois volitans and P. miles) were introduced to Florida waters during the mid to late 1980s, and eventually established self-sustaining breeding populations in the tropical western Atlantic. These invasive species are now widespread along the southeastern seaboard of the United States, across the Caribbean Sea, and in the Gulf of Mexico. In these regions, lionfish reach larger maximum sizes and higher abundances than they do in their native Pacific, suggesting that they have undergone ecological release. Invaded marine communities have thus far provided little if any biotic resistance. Lionfish are generalist predators with high consumption rates, inhabit a broad range of habitats, are defended from predation by venomous spines, and are capable of long-range larval dispersal. It is possible that lionfish have direct effects on native communities, through consumption of native fishes and competition with native predators, as well as indirect effects, such as overconsumption of herbivorous fishes that prevent seaweeds from outcompeting reef-building corals. There is also serious concern that invasive lionfish could act additively, or even synergistically, with existing stressors of coral-reef systems, such as overfishing and ocean warming, resulting in substantial negative consequences for native ecosystems and economically valuable fisheries. The primary goal of this dissertation was to conduct a set of controlled, replicated field experiments to rigorously examine and measure the effects of lionfish on native reef-fish communities across a range of spatial and temporal scales. In the first experiment (Chapter 2), the net recruitment of native fishes to twenty small patch reefs was compared in the presence (n = 10) and absence (n = 10) of lionfish. This study demonstrated that lionfish reduced net recruitment, or change in abundance of small native fishes, by an average (± SEM) of 78.9 ± 32.2 % over 5 weeks, affecting 23 of 38 species recruiting to reefs in both treatments. In a second experiment (Chapter 4), I examined the effects of lionfish on patch-reef communities of small native fishes relative to, and in combination with, those of a similarly sized native predator, the coney grouper (Cephalopholis fulva). Four different predator treatments were established by transplanting predators (n = 5 reefs each). Treatments included a single small invasive lionfish, a single small native grouper, a grouper and a lionfish together, and predator-free controls. Compared to controls, invasive lionfish caused reductions (mean ± SEM) in abundance (93.7 ± 17.8 %) and species richness (4.6 ± 1.6 species) of small native fishes. The negative effect of lionfish on abundance was 2.6 ± 0.5 times stronger than that of the native grouper. The greatest negative effects on abundance, species richness, evenness, and diversity of native fishes occurred when both lionfish and native grouper were present. Additionally, lionfish grew more than six times faster in both length and mass than did native grouper. A third experiment (Chapter 6) assessed the effects of lionfish on native reef-fish communities at spatial and temporal scales directly relevant to management and conservation efforts. Subsequent to baseline surveys, high- and low-density lionfish treatments were established on 10 large (1400 to 4000 m²) isolated coral reefs. After initiation of treatments, quarterly surveys of the native reef-fish communities were conducted for approximately 14 months. Lionfish caused significant reductions (mean ± SEM) in density (up to 3.22 ± 0.95 fish m⁻²), biomass (3.26 ± 1.10 g m⁻²), and species richness (4.92 ± 2.09 species) of small (<10 cm TL) native fishes. However, these negative effects on prey-sized fishes had not yet translated into declines in larger size classes during the first 14 months of this experiment. In addition to field experiments, this dissertation describes field and aquarium observations of a previously undocumented piscivorous behavior by invasive lionfish - blowing jets of water at prey fish - which may confer a high degree of predation efficiency, thus contributing to the dramatic success of the invasion (Chapter 5). Also provided is a review of the current state of knowledge about the lionfish invasion, with speculation on the long-term effects of the invasion on coral-reef communities, and a brief discussion of potential mitigation measures (Chapter 3). In sum, this research demonstrated that invasive lionfish have substantial negative effects on native communities of coral-reef fishes. In all cases, numerical reductions in small (prey-sized) native fishes caused by lionfish were substantial. Additionally, lionfish caused considerable reductions in native reef-fish species richness (via predation on rare species). These findings indicate that the lionfish invasion may have long-term, broad-scale impacts on the structure and function of coral-reef communities as a whole, potentially reducing the resilience of these systems to a myriad of existing stressors as well as their capacity to provide valuable ecosystem goods and services to humans. Close

• 12. [Article] Adapting to Climate Change on Western Public Lands: Addressing the Ecological Effects of Domestic, Wild, and Feral Ungulates

  NEWS COVERAGE: A news release based on this journal publication, which is written for a lay audience and has been approved by an author of the study, is available online: http://bit.ly/XFBYe2

  Citation × Citation Citation Abstract Copy Title: Adapting to Climate Change on Western Public Lands: Addressing the Ecological Effects of Domestic, Wild, and Feral Ungulates Author: DellaSala, Dominick A., Donahue, Deborah L., Rhodes, Jonathan J., O'Brien, Mary H., Beschta, Robert L., Fleischner, Thomas L., Karr, James R., Deacon-Williams, Cindy NEWS COVERAGE: A news release based on this journal publication, which is written for a lay audience and has been approved by an author of the study, is available online: http://bit.ly/XFBYe2 Title: Adapting to Climate Change on Western Public Lands: Addressing the Ecological Effects of Domestic, Wild, and Feral Ungulates Author: DellaSala, Dominick A., Donahue, Deborah L., Rhodes, Jonathan J., O'Brien, Mary H., Beschta, Robert L., Fleischner, Thomas L., Karr, James R., Deacon-Williams, Cindy NEWS COVERAGE: A news release based on this journal publication, which is written for a lay audience and has been approved by an author of the study, is available online: http://bit.ly/XFBYe2 Close

• 13. [Article] Key areas for conserving United States’ biodiversity likely threatened by future land use change

  This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by the Ecological Society of America. The published article can be found at: http://www.esajournal...

  Citation × Citation Citation Abstract Copy Title: Key areas for conserving United States’ biodiversity likely threatened by future land use change Author: Martinuzzi, S., Helmers, D. P., Higgins, J. V., Radeloff, V. C., Plantinga, A. J., Lewis, D. J. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by the Ecological Society of America. The published article can be found at: http://www.esajournals.org/loi/ecsp. Title: Key areas for conserving United States’ biodiversity likely threatened by future land use change Author: Martinuzzi, S., Helmers, D. P., Higgins, J. V., Radeloff, V. C., Plantinga, A. J., Lewis, D. J. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by the Ecological Society of America. The published article can be found at: http://www.esajournals.org/loi/ecsp. Close

• 14. [Article] The Biogeochemistry of nitrogen and phosphorus cycling in native shrub ecosystems in Senegal

  Two native shrub species (Piliostigma reticulatum and Guiera senegalensis) are prominent vegetation components in farmers’ fields in Senegal. However, their role in nutrient cycling and ecosystem function ...

  Citation × Citation Citation Abstract Copy Title: The Biogeochemistry of nitrogen and phosphorus cycling in native shrub ecosystems in Senegal Author: Dossa, Ekw'e Lokossou, 1960- Two native shrub species (Piliostigma reticulatum and Guiera senegalensis) are prominent vegetation components in farmers’ fields in Senegal. However, their role in nutrient cycling and ecosystem function has largely been overlooked. A study including both laboratory and field experiments was conducted to evaluate potential biophysical interactions of the two shrub species with soils and crops in Senegal. Carbon (C), nitrogen (N) and phosphorus (P) mineralization potential of soils incubated with residues of the two shrubs species was studied in laboratory conditions. Additionally, the effect of shrub-residue amendment on P sorption by soils was examined. Under field conditions, the effect of presence or absence of shrubs on crop productivity and nutrient recycling in soil was investigated. Another study examined shrub species effect on spatial distribution of nutrients and P fractions. Results showed shrub residues used as amendments immobilized N and P, which suggested these residues have limited value as immediate nutrient sources for crops. However, soils amended with shrub residues sorbed less P than unamended soils, indicating that when added to P-fixing soils, shrub residues could improve P availability to crops. In the absence of fertilization or when water was limiting, shrubs increased crop yield, likely through a combination of improved soil quality and water conditions associated with the shrub canopy and rhizosphere. The presence of shrubs increased nutrient-use efficiency over sole crop systems. Shrubs were shown to create “islands of fertility” that had greater C, N and P concentrations under their canopies than in open areas. Shrubs differed in their ability to modify soil properties. G. senegalensis had higher soil C and N under its canopy and lower pH than P. reticulatum. Sequential extraction of P fractions showed that NaOH-P, most of which is organic P, was the dominant P fraction in the soils. These results showed that, in the Sahel, shrubs are important components of cropping systems that should be conserved and actively managed. Title: The Biogeochemistry of nitrogen and phosphorus cycling in native shrub ecosystems in Senegal Author: Dossa, Ekw'e Lokossou, 1960- Two native shrub species (Piliostigma reticulatum and Guiera senegalensis) are prominent vegetation components in farmers’ fields in Senegal. However, their role in nutrient cycling and ecosystem function has largely been overlooked. A study including both laboratory and field experiments was conducted to evaluate potential biophysical interactions of the two shrub species with soils and crops in Senegal. Carbon (C), nitrogen (N) and phosphorus (P) mineralization potential of soils incubated with residues of the two shrubs species was studied in laboratory conditions. Additionally, the effect of shrub-residue amendment on P sorption by soils was examined. Under field conditions, the effect of presence or absence of shrubs on crop productivity and nutrient recycling in soil was investigated. Another study examined shrub species effect on spatial distribution of nutrients and P fractions. Results showed shrub residues used as amendments immobilized N and P, which suggested these residues have limited value as immediate nutrient sources for crops. However, soils amended with shrub residues sorbed less P than unamended soils, indicating that when added to P-fixing soils, shrub residues could improve P availability to crops. In the absence of fertilization or when water was limiting, shrubs increased crop yield, likely through a combination of improved soil quality and water conditions associated with the shrub canopy and rhizosphere. The presence of shrubs increased nutrient-use efficiency over sole crop systems. Shrubs were shown to create “islands of fertility” that had greater C, N and P concentrations under their canopies than in open areas. Shrubs differed in their ability to modify soil properties. G. senegalensis had higher soil C and N under its canopy and lower pH than P. reticulatum. Sequential extraction of P fractions showed that NaOH-P, most of which is organic P, was the dominant P fraction in the soils. These results showed that, in the Sahel, shrubs are important components of cropping systems that should be conserved and actively managed. Close

• 15. [Article] Short-term responses of native bees to livestock and implications for managing ecosystem services in grasslands

  This is the publisher’s final pdf. The published article is copyrighted by the Ecological Society of America and can be found at: http://www.esajournals.org/loi/ecsp.

  Citation × Citation Citation Abstract Copy Title: Short-term responses of native bees to livestock and implications for managing ecosystem services in grasslands Author: Schmalz, Heidi, Rao, Sujaya, Kennedy, Patricia L., Kimoto, Chiho, Thorp, Robbin W., DeBano, Sandra J., Johnson, Tracey, DelCurto, Timothy, Taylor, Robert V. This is the publisher’s final pdf. The published article is copyrighted by the Ecological Society of America and can be found at: http://www.esajournals.org/loi/ecsp. Title: Short-term responses of native bees to livestock and implications for managing ecosystem services in grasslands Author: Schmalz, Heidi, Rao, Sujaya, Kennedy, Patricia L., Kimoto, Chiho, Thorp, Robbin W., DeBano, Sandra J., Johnson, Tracey, DelCurto, Timothy, Taylor, Robert V. This is the publisher’s final pdf. The published article is copyrighted by the Ecological Society of America and can be found at: http://www.esajournals.org/loi/ecsp. Close

• 16. [Article] The predation of mudflat burrowing shrimp by native Oregon crabs Red rock crab (Cancer productus) and Dungeness crab (Cancer magister) versus an invasive crab European green crab (Carcius maenas)

  Yaquina Bay, Oregon, has been introduced to a few The invasive species in Yaquina Bay, Oregon can have a huge effect on the native species and local ecosystem. European green crab (Carcius maenas) is an ...

  Citation × Citation Citation Abstract Copy Title: The predation of mudflat burrowing shrimp by native Oregon crabs Red rock crab (Cancer productus) and Dungeness crab (Cancer magister) versus an invasive crab European green crab (Carcius maenas) Author: Trobaugh, Sean A Yaquina Bay, Oregon, has been introduced to a few The invasive species in Yaquina Bay, Oregon can have a huge effect on the native species and local ecosystem. European green crab (Carcius maenas) is an invasive species. The European green crab can be found on the mudflats competing with the native crabs, including Red rock crab (Cancer productus) and Dungeness crab (Cancer magister), for food. Possible prey includes mudflat burrowing shrimp, the Ghost shrimp, (Neotrypaea californiensis) and the Mud shrimp, (Upogebia pugettensis). Thus study examines native crab (primarily Red rock) and European green crab predation on mudflat burrowing shrimp with controlled laboratory predation experiments: putting shrimp in sediment, then adding crab after an allotted burrowing time. My hypothesis is that Red rock is able to eat more shrimp than the European green crab because of the mobility of the Red rock claws. Both invasive and native crabs preyed upon the shrimp, however, the native crabs are doing statically significant greater (p-value =.001) at getting this food source then the invasive crab. The European green crab is not out competing the Red rock and Dungeness. Title: The predation of mudflat burrowing shrimp by native Oregon crabs Red rock crab (Cancer productus) and Dungeness crab (Cancer magister) versus an invasive crab European green crab (Carcius maenas) Author: Trobaugh, Sean A Yaquina Bay, Oregon, has been introduced to a few The invasive species in Yaquina Bay, Oregon can have a huge effect on the native species and local ecosystem. European green crab (Carcius maenas) is an invasive species. The European green crab can be found on the mudflats competing with the native crabs, including Red rock crab (Cancer productus) and Dungeness crab (Cancer magister), for food. Possible prey includes mudflat burrowing shrimp, the Ghost shrimp, (Neotrypaea californiensis) and the Mud shrimp, (Upogebia pugettensis). Thus study examines native crab (primarily Red rock) and European green crab predation on mudflat burrowing shrimp with controlled laboratory predation experiments: putting shrimp in sediment, then adding crab after an allotted burrowing time. My hypothesis is that Red rock is able to eat more shrimp than the European green crab because of the mobility of the Red rock claws. Both invasive and native crabs preyed upon the shrimp, however, the native crabs are doing statically significant greater (p-value =.001) at getting this food source then the invasive crab. The European green crab is not out competing the Red rock and Dungeness. Close

• 17. [Article] Comparing Himalayan blackberry (Rubus armeniacus) management techniques in upland prairie communities of the W.L. Finley National Wildlife Refuge

  Dedicated to the preservation and promotion of many of the nation’s most threatened and endangered species, the W.L. Finley National Wildlife Refuge is highly invested in the management of some of the ...

  Citation × Citation Citation Abstract Copy Title: Comparing Himalayan blackberry (Rubus armeniacus) management techniques in upland prairie communities of the W.L. Finley National Wildlife Refuge Author: Ensley, Jona L. Dedicated to the preservation and promotion of many of the nation’s most threatened and endangered species, the W.L. Finley National Wildlife Refuge is highly invested in the management of some of the last remaining upland prairies once prevalent throughout Oregon's Willamette Valley. More than a century of land fragmentation, fire suppression, and cultivation has shifted species composition and physical structure of the native prairies toward woodland ecosystems, reducing habitat quality and quantity. This transition is greatly driven by the encroachment and introduction of the non-native, woody invader Himalayan blackberry (Rubus armeniacus). This study focused on the three most common Himalayan blackberry management techniques used within the refuge's upland prairies: late summer mowing, late summer burning, and a combination of both. The goal was to analyze the efficacy of each technique in meeting the refuge objectives of controlling Himalayan blackberry populations and promoting native prairie physiognomy after one application using a complete random block design. Findings were presented to refuge managers to facilitate improved management of these fragile communities. Mowing was found to have the greatest reduction in blackberry stem and plant density and resulted in the lowest resprout density post-treatment. This treatment also met the refuge objectives of reducing woody cover and increasing graminoid cover, but did little to increase herbaceous cover when compared to the control group. Burning produced no significant increase in herbaceous cover or reduction in woody cover and provided favorable conditions for Himalayan blackberry seedling germination, contributing to a larger blackberry problem in years to come. In promoting herbaceous habitat for upland-dependent species, mowing with subsequent burning was the most successful technique. Though not as effective in reducing blackberry vigor as mowing alone, this treatment showed the most potential of the three in managing for all objectives. Title: Comparing Himalayan blackberry (Rubus armeniacus) management techniques in upland prairie communities of the W.L. Finley National Wildlife Refuge Author: Ensley, Jona L. Dedicated to the preservation and promotion of many of the nation’s most threatened and endangered species, the W.L. Finley National Wildlife Refuge is highly invested in the management of some of the last remaining upland prairies once prevalent throughout Oregon's Willamette Valley. More than a century of land fragmentation, fire suppression, and cultivation has shifted species composition and physical structure of the native prairies toward woodland ecosystems, reducing habitat quality and quantity. This transition is greatly driven by the encroachment and introduction of the non-native, woody invader Himalayan blackberry (Rubus armeniacus). This study focused on the three most common Himalayan blackberry management techniques used within the refuge's upland prairies: late summer mowing, late summer burning, and a combination of both. The goal was to analyze the efficacy of each technique in meeting the refuge objectives of controlling Himalayan blackberry populations and promoting native prairie physiognomy after one application using a complete random block design. Findings were presented to refuge managers to facilitate improved management of these fragile communities. Mowing was found to have the greatest reduction in blackberry stem and plant density and resulted in the lowest resprout density post-treatment. This treatment also met the refuge objectives of reducing woody cover and increasing graminoid cover, but did little to increase herbaceous cover when compared to the control group. Burning produced no significant increase in herbaceous cover or reduction in woody cover and provided favorable conditions for Himalayan blackberry seedling germination, contributing to a larger blackberry problem in years to come. In promoting herbaceous habitat for upland-dependent species, mowing with subsequent burning was the most successful technique. Though not as effective in reducing blackberry vigor as mowing alone, this treatment showed the most potential of the three in managing for all objectives. Close

• 18. [Article] Economic and social impacts of restoration : a case study of the Great Basin Region

  The last five decades of research in arid land ecology cites Invasive species as a source of imbalances in biodiversity through habitat destruction and reductions of native species through ecosystem alterations ...

  Citation × Citation Citation Abstract Copy Title: Economic and social impacts of restoration : a case study of the Great Basin Region Author: Satyal, Vijayanand H. The last five decades of research in arid land ecology cites Invasive species as a source of imbalances in biodiversity through habitat destruction and reductions of native species through ecosystem alterations in favor of non-native species. Invasive species are known to damage not only the surrounding ecosystem but also cause economic and non-economic losses to society. This study focuses on economic and social impacts of controlling cheatgrass (Bromus tectorum L.) on the public rangelands of the Great Basin region. This research seeks to examine the economic and social impacts of adopting different restoration strategies (herbicide use, fire, grazing and re-seeding of native grasses). The economic study seeks to assess the cost-effectiveness of adopting any versus none of the restoration strategies using a linear programming multi-period optimization framework. In order to understand if restoration of cheatgrass is socially acceptable and whether the spatial context influences economic decisions, a parallel social attitudinal study examines the perceptions held by ranchers, interest groups, agency personnel and informed public with regard to restoration, the ongoing collaborative project and expected costs of undertaking restoration. The bio-economic study incorporates ranch production and ecological site specific data into representative optimization models and solves to maximize net ranch income subject to market and resource constraints. The economic study found restoration to impact the ranches financially as the degree of restoration increased. Costs of restoration were lowest under baseline conditions and increased in magnitude with use of grazing, fire, herbicide and the integrated strategy respectively. Attitudinal data indicated that the meaning of restoration and social acceptability towards restoration strategies differed within and across stakeholder groups in the Great Basin states of Oregon, Idaho, Nevada and Utah. Title: Economic and social impacts of restoration : a case study of the Great Basin Region Author: Satyal, Vijayanand H. The last five decades of research in arid land ecology cites Invasive species as a source of imbalances in biodiversity through habitat destruction and reductions of native species through ecosystem alterations in favor of non-native species. Invasive species are known to damage not only the surrounding ecosystem but also cause economic and non-economic losses to society. This study focuses on economic and social impacts of controlling cheatgrass (Bromus tectorum L.) on the public rangelands of the Great Basin region. This research seeks to examine the economic and social impacts of adopting different restoration strategies (herbicide use, fire, grazing and re-seeding of native grasses). The economic study seeks to assess the cost-effectiveness of adopting any versus none of the restoration strategies using a linear programming multi-period optimization framework. In order to understand if restoration of cheatgrass is socially acceptable and whether the spatial context influences economic decisions, a parallel social attitudinal study examines the perceptions held by ranchers, interest groups, agency personnel and informed public with regard to restoration, the ongoing collaborative project and expected costs of undertaking restoration. The bio-economic study incorporates ranch production and ecological site specific data into representative optimization models and solves to maximize net ranch income subject to market and resource constraints. The economic study found restoration to impact the ranches financially as the degree of restoration increased. Costs of restoration were lowest under baseline conditions and increased in magnitude with use of grazing, fire, herbicide and the integrated strategy respectively. Attitudinal data indicated that the meaning of restoration and social acceptability towards restoration strategies differed within and across stakeholder groups in the Great Basin states of Oregon, Idaho, Nevada and Utah. Close

• 19. [Article] Temporal Genetic Variance and Propagule-Driven Genetic Structure Characterize Naturalized Rainbow Trout (Oncorhynchus mykiss) from a Patagonian Lake Impacted by Trout Farming

  This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by Public Library of Science. The published article can be found at: http://www.plosone.org/

  Citation × Citation Citation Abstract Copy Title: Temporal Genetic Variance and Propagule-Driven Genetic Structure Characterize Naturalized Rainbow Trout (Oncorhynchus mykiss) from a Patagonian Lake Impacted by Trout Farming Author: Arismendi, Ivan, Seeb, Lisa W., Seeb, James E., et al., Benavente, Javiera N. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by Public Library of Science. The published article can be found at: http://www.plosone.org/ Title: Temporal Genetic Variance and Propagule-Driven Genetic Structure Characterize Naturalized Rainbow Trout (Oncorhynchus mykiss) from a Patagonian Lake Impacted by Trout Farming Author: Arismendi, Ivan, Seeb, Lisa W., Seeb, James E., et al., Benavente, Javiera N. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by Public Library of Science. The published article can be found at: http://www.plosone.org/ Close

• 20. [Article] A sustainable resource development plan framework for the Neskonlith Indian Band, British Columbia

  A sustainable resource development plan framework was prepared for the Neskonlith Indian Band, who are located in the interior of British Columbia, Canada. The framework intends to address issues involving; ...

  Citation × Citation Citation Abstract Copy Title: A sustainable resource development plan framework for the Neskonlith Indian Band, British Columbia Author: Mackasey, J. Patrick A sustainable resource development plan framework was prepared for the Neskonlith Indian Band, who are located in the interior of British Columbia, Canada. The framework intends to address issues involving; integrated resource management, traditional native land management, ecosystem management, and community-based resource management. A soft systems (Wilson & Morren, 1990) methodology was used to work with the community and help assess the current management state and to begin the process of determining the desired future condition of their land base and how this can help build the community. However, the band was prepared only to work through the first two (out of seven) stages of the methodology. The study area used was 4259 ha in size, of which 1316 ha was reserve land. A good portion of this area is forested (52.4%), primarily with interior Douglas-Fir (Pseudotsuga menziesii var, glauca). The study area is also represented by 13.9% open range, 8,2% cultivated land and a large lake (11 %) . Current and past resource management activities on this area include; forestry, mining, agriculture, range, recreation, and parks. The band is interested in how the land base can be managed from an integrated resource management perspective and in learning how non-consumptive uses of the forest can be further explored. This framework attempts to answer the questions and provide the band with a working Geographic Information System database and some management alternatives to examine. A Terrasoft GIS was used, which allowed for both vector and raster processing. Data layers were compiled and assembled for a variety of resource values. These data layers were analyzed using models which produced three management alternatives. These alternatives included the following emphases: economic; ecological; and balanced. The economic alternative focused solely on resource extraction. The ecological alternative focuses on protection of the environment as the main emphasis, and large parcels of land are excluded from any resource development activities. The balanced alternative offered a balance between the first two alternatives, allowing for a reasonable level of resource management activities, while protecting important ecological components across the landscape. The trade-offs expected to be encountered with each management scenario were discussed with the community and the balanced alternative was resolved as the preferred choice. This framework is expected to be used by the band to help construct a comprehensive integrated resource management plan. Recommendations are provided with the third management alternative to assist the band with integrated resource management planning. It was concluded that although the band has much information available on resource management, they still have a great deal of work left ahead of them to become fully involved in a functional, integrated resource management program. Title: A sustainable resource development plan framework for the Neskonlith Indian Band, British Columbia Author: Mackasey, J. Patrick A sustainable resource development plan framework was prepared for the Neskonlith Indian Band, who are located in the interior of British Columbia, Canada. The framework intends to address issues involving; integrated resource management, traditional native land management, ecosystem management, and community-based resource management. A soft systems (Wilson & Morren, 1990) methodology was used to work with the community and help assess the current management state and to begin the process of determining the desired future condition of their land base and how this can help build the community. However, the band was prepared only to work through the first two (out of seven) stages of the methodology. The study area used was 4259 ha in size, of which 1316 ha was reserve land. A good portion of this area is forested (52.4%), primarily with interior Douglas-Fir (Pseudotsuga menziesii var, glauca). The study area is also represented by 13.9% open range, 8,2% cultivated land and a large lake (11 %) . Current and past resource management activities on this area include; forestry, mining, agriculture, range, recreation, and parks. The band is interested in how the land base can be managed from an integrated resource management perspective and in learning how non-consumptive uses of the forest can be further explored. This framework attempts to answer the questions and provide the band with a working Geographic Information System database and some management alternatives to examine. A Terrasoft GIS was used, which allowed for both vector and raster processing. Data layers were compiled and assembled for a variety of resource values. These data layers were analyzed using models which produced three management alternatives. These alternatives included the following emphases: economic; ecological; and balanced. The economic alternative focused solely on resource extraction. The ecological alternative focuses on protection of the environment as the main emphasis, and large parcels of land are excluded from any resource development activities. The balanced alternative offered a balance between the first two alternatives, allowing for a reasonable level of resource management activities, while protecting important ecological components across the landscape. The trade-offs expected to be encountered with each management scenario were discussed with the community and the balanced alternative was resolved as the preferred choice. This framework is expected to be used by the band to help construct a comprehensive integrated resource management plan. Recommendations are provided with the third management alternative to assist the band with integrated resource management planning. It was concluded that although the band has much information available on resource management, they still have a great deal of work left ahead of them to become fully involved in a functional, integrated resource management program. Close

• 21. [Article] Seed and establishment limitation contribute to long-term native forb declines in California grasslands

  This is the publisher’s final pdf. The published article is copyrighted by Ecological Society of America and can be found at: http://www.esa.org/.

  Citation × Citation Citation Abstract Copy Title: Seed and establishment limitation contribute to long-term native forb declines in California grasslands Author: Brandt, Angela J., Seabloom, Eric W. This is the publisher’s final pdf. The published article is copyrighted by Ecological Society of America and can be found at: http://www.esa.org/. Title: Seed and establishment limitation contribute to long-term native forb declines in California grasslands Author: Brandt, Angela J., Seabloom, Eric W. This is the publisher’s final pdf. The published article is copyrighted by Ecological Society of America and can be found at: http://www.esa.org/. Close

• 22. [Article] Germination and establishment in Willamette Valley native prairie plants

  Native plants provide many ecosystem services while also having great beauty and are a valuable component of the landscape. As use of these plants in habitat restoration, agricultural insectary plantings, ...

  Citation × Citation Citation Abstract Copy Title: Germination and establishment in Willamette Valley native prairie plants Author: Russell, Michael C. Native plants provide many ecosystem services while also having great beauty and are a valuable component of the landscape. As use of these plants in habitat restoration, agricultural insectary plantings, and home landscapes increases so does demand for information on the basic biology of a group of species that have only been sparingly studied. Germination is one of the first major events in a plant’s life cycle and can be affected by both the physiological state of the seed and the environment the seed is in. Seeds can become dormant and may require some environmental signal for germination. I conducted a series of germination trials on a set of Willamette Valley native prairie plants to test whether cold stratification or various scarification treatments can be used to break seed dormancy. I used each species’ responses to classify the dormancy type of each species. The environmental conditions that the seed experiences also affect germination. The effect of temperature on germination was studied using a temperature gradient table. Seeds were tested to characterize species based on the temperature range at which its seeds can germinate. Germination in some species was bounded within clearly defined temperature limits, while germination in others occurred over the full range of studied temperatures. The germination data were modeled with linear regression to create standard estimates for the physiological limits of each species to allow for comparisons between the species. After seeds germinate the initial stages of establishment can have great implications on the survival of the plant. A greenhouse experiment was conducted to study the competitive interactions of six of the species. Plants were grown together in pots for 90 days and biomass collected. The mean competitive effect and competitive response of each species was calculated and the results were regressed against each species' values for several physiological traits that were available from the literature. The experiment found that species with higher relative growth rates had greater competitive effects on other species. The first two experiments measured physiological traits of several Oregon native species. The third demonstrated the utility of standardized traits in predicting ecological behavior. This trait based approach has great potential as a tool for comparing ecological similarities and differences across different ecosystems and different species pools. Title: Germination and establishment in Willamette Valley native prairie plants Author: Russell, Michael C. Native plants provide many ecosystem services while also having great beauty and are a valuable component of the landscape. As use of these plants in habitat restoration, agricultural insectary plantings, and home landscapes increases so does demand for information on the basic biology of a group of species that have only been sparingly studied. Germination is one of the first major events in a plant’s life cycle and can be affected by both the physiological state of the seed and the environment the seed is in. Seeds can become dormant and may require some environmental signal for germination. I conducted a series of germination trials on a set of Willamette Valley native prairie plants to test whether cold stratification or various scarification treatments can be used to break seed dormancy. I used each species’ responses to classify the dormancy type of each species. The environmental conditions that the seed experiences also affect germination. The effect of temperature on germination was studied using a temperature gradient table. Seeds were tested to characterize species based on the temperature range at which its seeds can germinate. Germination in some species was bounded within clearly defined temperature limits, while germination in others occurred over the full range of studied temperatures. The germination data were modeled with linear regression to create standard estimates for the physiological limits of each species to allow for comparisons between the species. After seeds germinate the initial stages of establishment can have great implications on the survival of the plant. A greenhouse experiment was conducted to study the competitive interactions of six of the species. Plants were grown together in pots for 90 days and biomass collected. The mean competitive effect and competitive response of each species was calculated and the results were regressed against each species' values for several physiological traits that were available from the literature. The experiment found that species with higher relative growth rates had greater competitive effects on other species. The first two experiments measured physiological traits of several Oregon native species. The third demonstrated the utility of standardized traits in predicting ecological behavior. This trait based approach has great potential as a tool for comparing ecological similarities and differences across different ecosystems and different species pools. Close

• 23. [Article] Habitat relationships of native and non-native fishes of the Willamette River, Oregon

  The Willamette River flows north between the Cascade Mountains and Coast Range of western Oregon within a 29,728-km² basin. The fish community in the geologically young basin consists of 36 native species, ...

  Citation × Citation Citation Abstract Copy Title: Habitat relationships of native and non-native fishes of the Willamette River, Oregon Author: Williams, Joshua E. (Joshua Everett) The Willamette River flows north between the Cascade Mountains and Coast Range of western Oregon within a 29,728-km² basin. The fish community in the geologically young basin consists of 36 native species, but introductions of non-native fishes have added 33 additional species for a total of 69 fish species. During the summers of 2011-2013, fish distributions were sampled from the confluence of the McKenzie River downstream to the confluence of the Columbia River to assess: (1) fish community composition, (2) differences in community composition between mainstem river and slough habitats, and (3) relationships between native and non-native fish species and physical habitat characteristics. In addition, a 182-ha seasonally inundated floodplain habitat along the middle Willamette River was sampled during winter 2011 through spring 2012 to assess: (1) fish community composition, (2) spawning and rearing, and (3) timing of use and movement by fish species. Throughout the three years of longitudinal sampling, 36,586 fish were collected comprising 41 species, 22 native and 19 non-native. Overall, native fish represented 93% of the total fish sampled. Higher numbers of fish were collected in the upper river, and higher proportions of those fish were native species. Though non-native fish were more common in slough habitats than mainstem sties, the majority of fish collected in both habitat types were native. The strongest environmental predictors of fish community were quantitative measures of longitudinal distance, velocity, depth, percent macrophyte cover and percent embeddedness. Habitat type (slough versus mainstem) was also a significant predictor. Native fish species exhibited greater variability in habitat relationships than non-native fishes, though several native species were strongly associated with specific environmental attributes. Non-native species were more associated with slough habitats and sites with high amount of macrophyte growth and embedded substrates. Overall, 25 species had a high fidelity to mainstem or slough habitats. Equal numbers of native species showed a fidelity to either mainstem or slough sites, but non-native species were significantly related only to slough habitats. In the seasonally inundated floodplain habitat, an estimated 43,000 fish were collected comprising 23 species; 12 native and 11 non-native. Of these 98.1% were native. The most common native species were threespine stickleback Gasterosteus aculeatus and peamouth Mylocheilus caurinus while the most common non-native species were bluegill Lepomis macrochirus and western mosquitofish Gambusia affinus. Several species used the inundated floodplain for spawning and rearing, particularly threespine stickleback, peamouth and western mosquitofish. With the exception of young-of-year threespine stickleback, native species were collected mostly in the beginning and middle of the sampling period while non-native species were collected in the latter portion of the sampling. The Willamette River Basin has a long history of environmental modification. Understanding relationships of a broad range of species to their environment and to each other provides a technical foundation for ecosystem based management by state and federal agencies, local municipalities, and private landowners. The need for ecosystem based management is vital for future conservation and recovery of large river floodplain ecosystems. Title: Habitat relationships of native and non-native fishes of the Willamette River, Oregon Author: Williams, Joshua E. (Joshua Everett) The Willamette River flows north between the Cascade Mountains and Coast Range of western Oregon within a 29,728-km² basin. The fish community in the geologically young basin consists of 36 native species, but introductions of non-native fishes have added 33 additional species for a total of 69 fish species. During the summers of 2011-2013, fish distributions were sampled from the confluence of the McKenzie River downstream to the confluence of the Columbia River to assess: (1) fish community composition, (2) differences in community composition between mainstem river and slough habitats, and (3) relationships between native and non-native fish species and physical habitat characteristics. In addition, a 182-ha seasonally inundated floodplain habitat along the middle Willamette River was sampled during winter 2011 through spring 2012 to assess: (1) fish community composition, (2) spawning and rearing, and (3) timing of use and movement by fish species. Throughout the three years of longitudinal sampling, 36,586 fish were collected comprising 41 species, 22 native and 19 non-native. Overall, native fish represented 93% of the total fish sampled. Higher numbers of fish were collected in the upper river, and higher proportions of those fish were native species. Though non-native fish were more common in slough habitats than mainstem sties, the majority of fish collected in both habitat types were native. The strongest environmental predictors of fish community were quantitative measures of longitudinal distance, velocity, depth, percent macrophyte cover and percent embeddedness. Habitat type (slough versus mainstem) was also a significant predictor. Native fish species exhibited greater variability in habitat relationships than non-native fishes, though several native species were strongly associated with specific environmental attributes. Non-native species were more associated with slough habitats and sites with high amount of macrophyte growth and embedded substrates. Overall, 25 species had a high fidelity to mainstem or slough habitats. Equal numbers of native species showed a fidelity to either mainstem or slough sites, but non-native species were significantly related only to slough habitats. In the seasonally inundated floodplain habitat, an estimated 43,000 fish were collected comprising 23 species; 12 native and 11 non-native. Of these 98.1% were native. The most common native species were threespine stickleback Gasterosteus aculeatus and peamouth Mylocheilus caurinus while the most common non-native species were bluegill Lepomis macrochirus and western mosquitofish Gambusia affinus. Several species used the inundated floodplain for spawning and rearing, particularly threespine stickleback, peamouth and western mosquitofish. With the exception of young-of-year threespine stickleback, native species were collected mostly in the beginning and middle of the sampling period while non-native species were collected in the latter portion of the sampling. The Willamette River Basin has a long history of environmental modification. Understanding relationships of a broad range of species to their environment and to each other provides a technical foundation for ecosystem based management by state and federal agencies, local municipalities, and private landowners. The need for ecosystem based management is vital for future conservation and recovery of large river floodplain ecosystems. Close

• 24. [Article] The effects of native plants on non-native plant abundance in a restoration setting : differences among native species and the predictive ability of species traits

  Reducing the cover of non-native species is one of the challenges of ecosystem restoration. The goal of this study is to identify native species traits that will increase native species cover and reduce ...

  Citation × Citation Citation Abstract Copy Title: The effects of native plants on non-native plant abundance in a restoration setting : differences among native species and the predictive ability of species traits Author: Goodridge, Jennifer M. Reducing the cover of non-native species is one of the challenges of ecosystem restoration. The goal of this study is to identify native species traits that will increase native species cover and reduce non-native species cover in the first growing season at upland and wetland prairie restoration sites. Native and non-native prairie species were planted in the fall and harvested the following summer at both an upland and a wetland site. Native species traits, such as plant weight, leaf area, relative growth rate, leaf area ratio, leaf weight ratio, net assimilation rate, and specific leaf area were measured under laboratory conditions for 7- and 21-day old seedlings. Germination rate (laboratory) and phenology (field) were also measured. At the upland site, species with a large 7-day plant weight and a high germination rate also had high native cover in the field (P<0.00l, R²=0.83). At the wetland site, high 21-day leaf area, low 21-day leaf weight ratio, and high net assimilation rate predicted increased native cover in the field (P<0.00l, R²=0.87). An abundance of natives, as measured by native cover, native biomass, and number of individuals, likely results in fewer resources (light, nutrients, and water) available for the non-native species growth resulting in a reduction in the non-native cover. Intrinsic traits of native species also predicted the field performance of non-native species, although the amount of variation explained was lower than the amount of variation explained in the models that predicted native cover. In the upland site, native species with high leaf weight ratio (21-day) tended to have lower non-native cover in their field plots (P=0.087, R²=0.23). In the wetland site, the native species traits that predict non-native cover were low 21-day leaf area and high 21-day leaf weight ratio (P<0.00l, R²=0.46). These traits were similar to those that predicted native species cover at the wetland site. This study demonstrates the ability of species traits to predict field performance. Predictive models were generated using native species traits to select species for restoration that will increase native cover and decrease non-native cover in the first growing season. Traits can be measured for species not included in this study and the models generated can be used to predict the field performance of species at similar sites. Title: The effects of native plants on non-native plant abundance in a restoration setting : differences among native species and the predictive ability of species traits Author: Goodridge, Jennifer M. Reducing the cover of non-native species is one of the challenges of ecosystem restoration. The goal of this study is to identify native species traits that will increase native species cover and reduce non-native species cover in the first growing season at upland and wetland prairie restoration sites. Native and non-native prairie species were planted in the fall and harvested the following summer at both an upland and a wetland site. Native species traits, such as plant weight, leaf area, relative growth rate, leaf area ratio, leaf weight ratio, net assimilation rate, and specific leaf area were measured under laboratory conditions for 7- and 21-day old seedlings. Germination rate (laboratory) and phenology (field) were also measured. At the upland site, species with a large 7-day plant weight and a high germination rate also had high native cover in the field (P<0.00l, R²=0.83). At the wetland site, high 21-day leaf area, low 21-day leaf weight ratio, and high net assimilation rate predicted increased native cover in the field (P<0.00l, R²=0.87). An abundance of natives, as measured by native cover, native biomass, and number of individuals, likely results in fewer resources (light, nutrients, and water) available for the non-native species growth resulting in a reduction in the non-native cover. Intrinsic traits of native species also predicted the field performance of non-native species, although the amount of variation explained was lower than the amount of variation explained in the models that predicted native cover. In the upland site, native species with high leaf weight ratio (21-day) tended to have lower non-native cover in their field plots (P=0.087, R²=0.23). In the wetland site, the native species traits that predict non-native cover were low 21-day leaf area and high 21-day leaf weight ratio (P<0.00l, R²=0.46). These traits were similar to those that predicted native species cover at the wetland site. This study demonstrates the ability of species traits to predict field performance. Predictive models were generated using native species traits to select species for restoration that will increase native cover and decrease non-native cover in the first growing season. Traits can be measured for species not included in this study and the models generated can be used to predict the field performance of species at similar sites. Close

• 25. [Article] Native bee diversity and floral resource availability in two Willamette Valley Oregon ecosystems

  The importance of pollinators in native and managed landscapes is well known, and recent interest is directed towards investigating the role of native bees as providers of pollination ecosystem services. ...

  Citation × Citation Citation Abstract Copy Title: Native bee diversity and floral resource availability in two Willamette Valley Oregon ecosystems Author: Bergh, Jennifer E. The importance of pollinators in native and managed landscapes is well known, and recent interest is directed towards investigating the role of native bees as providers of pollination ecosystem services. Uncertainty about bee populations at global and local scales has prompted research and general interest in conservation of bee diversity. To sustain robust populations, bees need nesting habitat and quality forage resources. This thesis describes two studies related to the relationship between bee diversity and landscape floral resource availability in two Willamette Valley ecosystems: wet prairies and blueberry agroecosystems. The wetlands are florally diverse, heterogeneous, and temporally patchy in spring and summer, whereas blueberries are florally abundant during spring crop bloom with potentially fewer floral resources after berry set; the intention of these studies was to determine if the floral resources in each ecosystem were adequate to support robust native bee communities. For each site type, the bee fauna and associated melittophilous floral resources are described and characterized. In the studies, it was determined that bee diversity, and specifically bee abundance, was positively correlated with floral resources. This thesis presents the results of community analyses, floral resources that were identified as important forage sources, and a discussion of the relationship between landscape phenology and bee population dynamics in each ecosystem type. Implications and recommendations for landscape management to conserve and potentially enhance local native bee communities are discussed. Title: Native bee diversity and floral resource availability in two Willamette Valley Oregon ecosystems Author: Bergh, Jennifer E. The importance of pollinators in native and managed landscapes is well known, and recent interest is directed towards investigating the role of native bees as providers of pollination ecosystem services. Uncertainty about bee populations at global and local scales has prompted research and general interest in conservation of bee diversity. To sustain robust populations, bees need nesting habitat and quality forage resources. This thesis describes two studies related to the relationship between bee diversity and landscape floral resource availability in two Willamette Valley ecosystems: wet prairies and blueberry agroecosystems. The wetlands are florally diverse, heterogeneous, and temporally patchy in spring and summer, whereas blueberries are florally abundant during spring crop bloom with potentially fewer floral resources after berry set; the intention of these studies was to determine if the floral resources in each ecosystem were adequate to support robust native bee communities. For each site type, the bee fauna and associated melittophilous floral resources are described and characterized. In the studies, it was determined that bee diversity, and specifically bee abundance, was positively correlated with floral resources. This thesis presents the results of community analyses, floral resources that were identified as important forage sources, and a discussion of the relationship between landscape phenology and bee population dynamics in each ecosystem type. Implications and recommendations for landscape management to conserve and potentially enhance local native bee communities are discussed. Close

• 26. [Article] Vegetation response to prescribed fire in mountain big sagebrush ecosystems at Lava Beds National Monument, California

  Anthropogenic land use alterations such as livestock grazing and fire suppression have greatly altered sagebrush grasslands of the Great Basin, facilitating invasion of exotic annuals, increases in woody ...

  Citation × Citation Citation Abstract Copy Title: Vegetation response to prescribed fire in mountain big sagebrush ecosystems at Lava Beds National Monument, California Author: Ellsworth, Lisa M. Anthropogenic land use alterations such as livestock grazing and fire suppression have greatly altered sagebrush grasslands of the Great Basin, facilitating invasion of exotic annuals, increases in woody species, and losses of native species. Much of the current research surrounding wildland and prescribed fire in sagebrush dominated ecosystems has focused on a persistent belief that fire in sagebrush systems results in a loss of native flora and a trend toward dominance by exotic annuals. Fire was historically the dominant disturbance throughout the sagebrush steppe and the plant species that comprised these communities possess a variety of adaptations facilitating survival to the fire regime. In order to restore ecosystems, land managers will need to reintroduce natural ecosystem processes, including natural disturbance processes. To describe the response of these plant communities to fire, I examined the plant community response, seedbank response, and reproductive and density responses of three native bunchgrasses (Pseudoroegneria spicata, Achnatherum therberianum, and Elymus elymoides) as well as one native forb (Calochortus macrocarpus) following spring and fall prescribed fires at Lava Beds National Monument. Fires were applied to three Artemisia tridentata ssp. vaseyana (Mountain Big Sagebrush) plant communities with different land use and fire histories. These communities were different in composition ranging from a dominance of exotic annuals to dominance by native grasses, shrubs, and trees. Little is known about how prescribed fire affects the soil seed bank in sagebrush-dominated ecosystems. To address this, we quantified the emergence of Bromus tectorum (cheatgrass) seedlings as well as emergence of seedlings of functional groups (native forbs, bunchgrasses, and shrubs) in a seedbank germination study. At the invasive dominated site (Gillems Camp), we found 91% fewer B. tectorum seedlings germinated in spring burned sites than in controls immediately following spring prescribed burns. However, soils collected one-year following fire had 40% more B. tectorum germinants (8017 germinants/m [superscript 2]) than unburned controls (5132 germinants/m [superscript 2]). Following fall burns at this site there was a similar response, with a 56% immediate reduction in B. tectorum (as compared to unburned control) and a 59% increase in B. tectorum and 58% increase in exotic forb germinants one year following fires. There was an increase in native forb germination following spring burns (94%) and fall burns (45%) at a site dominated by native plants (Fleener Chimneys). Native bunchgrass seed germination declined following spring fire in sites dominated by sagebrush and native understory vegetation (79%), and in sites where Juniperus occidentalis (western juniper) and other woody species dominated (Merrill Caves) (71%). In invasive-dominated sites (Gillems Camp), there was a decrease in B. tectorum cover following both spring (81% decrease) and fall fires (82% decrease), and little native vegetation composition change. Shrub cover, made up predominantly of Chrysothamnus nauseosus, decreased following spring (95% decrease) and fall (93% decrease) fires. At the sagebrush, native understory site (Fleener Chimneys), there was a reduction in native bunchgrass cover (64% decrease), and an increase in native forbs (168% increase) following spring burns, with no changes following fall fires. At the juniper- woody dominated site (Merrill Caves), fire treatments resulted in a decrease in woody plant cover, with no immediate postfire differences seen in the herbaceous plant community. Density of bunchgrass species (Pseudoroegneria spicata, Achnatherum therberianum, Elymus elymoides) did not change following either spring or fall prescribed fire treatments. Fire enhanced flowering was not seen in C. macrocarpus following spring or fall burns at the native or juniper dominated sites. There was increased reproductive effort in native bunchgrass species following fires in all communities studied. Following spring fires at invasive dominated sites, there was a 245% increase in reproductive culms of P. spicata. Following fall fires in native dominated sites, we saw a 974% increase in reproductive culms of P. spicata and a 184% increase in reproductive culms of A. therberianum. Following fall fires at juniper-dominated sites, we saw in an increase in reproductive culms of P. spicata (678% increase), A. thurberianum (356% increase), and Elymus elymoides (209% increase). These results suggest that implementing prescribed fire in order to restore the natural disturbance regime in these fire-adapted ecosystems is beneficial to restoration and preservation of the native biota. Title: Vegetation response to prescribed fire in mountain big sagebrush ecosystems at Lava Beds National Monument, California Author: Ellsworth, Lisa M. Anthropogenic land use alterations such as livestock grazing and fire suppression have greatly altered sagebrush grasslands of the Great Basin, facilitating invasion of exotic annuals, increases in woody species, and losses of native species. Much of the current research surrounding wildland and prescribed fire in sagebrush dominated ecosystems has focused on a persistent belief that fire in sagebrush systems results in a loss of native flora and a trend toward dominance by exotic annuals. Fire was historically the dominant disturbance throughout the sagebrush steppe and the plant species that comprised these communities possess a variety of adaptations facilitating survival to the fire regime. In order to restore ecosystems, land managers will need to reintroduce natural ecosystem processes, including natural disturbance processes. To describe the response of these plant communities to fire, I examined the plant community response, seedbank response, and reproductive and density responses of three native bunchgrasses (Pseudoroegneria spicata, Achnatherum therberianum, and Elymus elymoides) as well as one native forb (Calochortus macrocarpus) following spring and fall prescribed fires at Lava Beds National Monument. Fires were applied to three Artemisia tridentata ssp. vaseyana (Mountain Big Sagebrush) plant communities with different land use and fire histories. These communities were different in composition ranging from a dominance of exotic annuals to dominance by native grasses, shrubs, and trees. Little is known about how prescribed fire affects the soil seed bank in sagebrush-dominated ecosystems. To address this, we quantified the emergence of Bromus tectorum (cheatgrass) seedlings as well as emergence of seedlings of functional groups (native forbs, bunchgrasses, and shrubs) in a seedbank germination study. At the invasive dominated site (Gillems Camp), we found 91% fewer B. tectorum seedlings germinated in spring burned sites than in controls immediately following spring prescribed burns. However, soils collected one-year following fire had 40% more B. tectorum germinants (8017 germinants/m [superscript 2]) than unburned controls (5132 germinants/m [superscript 2]). Following fall burns at this site there was a similar response, with a 56% immediate reduction in B. tectorum (as compared to unburned control) and a 59% increase in B. tectorum and 58% increase in exotic forb germinants one year following fires. There was an increase in native forb germination following spring burns (94%) and fall burns (45%) at a site dominated by native plants (Fleener Chimneys). Native bunchgrass seed germination declined following spring fire in sites dominated by sagebrush and native understory vegetation (79%), and in sites where Juniperus occidentalis (western juniper) and other woody species dominated (Merrill Caves) (71%). In invasive-dominated sites (Gillems Camp), there was a decrease in B. tectorum cover following both spring (81% decrease) and fall fires (82% decrease), and little native vegetation composition change. Shrub cover, made up predominantly of Chrysothamnus nauseosus, decreased following spring (95% decrease) and fall (93% decrease) fires. At the sagebrush, native understory site (Fleener Chimneys), there was a reduction in native bunchgrass cover (64% decrease), and an increase in native forbs (168% increase) following spring burns, with no changes following fall fires. At the juniper- woody dominated site (Merrill Caves), fire treatments resulted in a decrease in woody plant cover, with no immediate postfire differences seen in the herbaceous plant community. Density of bunchgrass species (Pseudoroegneria spicata, Achnatherum therberianum, Elymus elymoides) did not change following either spring or fall prescribed fire treatments. Fire enhanced flowering was not seen in C. macrocarpus following spring or fall burns at the native or juniper dominated sites. There was increased reproductive effort in native bunchgrass species following fires in all communities studied. Following spring fires at invasive dominated sites, there was a 245% increase in reproductive culms of P. spicata. Following fall fires in native dominated sites, we saw a 974% increase in reproductive culms of P. spicata and a 184% increase in reproductive culms of A. therberianum. Following fall fires at juniper-dominated sites, we saw in an increase in reproductive culms of P. spicata (678% increase), A. thurberianum (356% increase), and Elymus elymoides (209% increase). These results suggest that implementing prescribed fire in order to restore the natural disturbance regime in these fire-adapted ecosystems is beneficial to restoration and preservation of the native biota. Close

• 27. [Article] Drivers of plant community dynamics in sagebrush steppe ecosystems : cattle grazing, heat and water stress

  Sagebrush steppe ecosystems are one of the most widespread but endangered ecosystems in North America. A diverse array of human-related stressors has gradually compromised these ecosystems' resilience ...

  Citation × Citation Citation Abstract Copy Title: Drivers of plant community dynamics in sagebrush steppe ecosystems : cattle grazing, heat and water stress Author: Reisner, Michael D. Sagebrush steppe ecosystems are one of the most widespread but endangered ecosystems in North America. A diverse array of human-related stressors has gradually compromised these ecosystems' resilience to disturbance and invasion by Bromus tectorum (cheatgrass). The role of the foundational shrub Artemisia as a driver of herbaceous community structure and dynamics during this degradation process is poorly understood. Many of the individual factors driving B. tectorum invasions are well documented. However a predictive understanding of the relative importance of complex, interacting factors in the causal network of simultaneously occurring processes determining invasibility has proven elusive. I examined these issues at the landscape level across 75 sites capturing a range of soil and landscape properties and cattle grazing levels similar to those found across the Great Basin. Cumulative cattle herbivory stress levels were a predominant component of both the overlapping heat and water stress gradients driving the structure of Artemisia interactions with herbaceous species. Consistent with the stress gradient hypothesis, Artemisia facilitation of herbaceous species was most frequent and strongest at the highest stress levels, and competition was most frequent and strongest at the lowest stress levels. The two species with the highest competitive response abilities, Elymus elymoides and Poa secunda, showed the strongest facilitation at the upper limits of their stress tolerances. The structure of Artemisia interactions with the invasive B. tectorum was strikingly different than those with native bunchgrasses. Artemisia interactions with native bunchgrasses shifted from competition to facilitation with increasing heat, water, and herbivory stress, but its interactions remained competitive with B. tectorum along the entire stress gradient. Shifts in the structure of interactions between Artemisia and native bunchgrasses were associated with both an increase and decrease in community compositional and functional stability. I report the first evidence of native species facilitation decreasing community invasibility. Artemisia facilitation increased native bunchgrass composition, which reduced the magnitude of B. tectorum invasion in under-shrub compared to interspace communities. This decreased invasibility did not translate into lower invasibility at the community level because of the limited spatial scale over which such facilitation occurs. Artemisia facilitation increased community compositional and functional stability at intermediate stress levels but decreased community stability at high stress levels. Facilitation became a destabilizing force when native bunchgrass species became "obligate" beneficiaries, i.e. strongly dependent on Artemisia facilitation for their continued persistence in the community. Structural equation modeling assessed the structure of the causal network and relative importance of factors and processes predicted to drive community invasibility. The linchpin of ecosystem invasibility was the size of and connectivity between basal gaps in perennial vegetation, driven by shifts in the structure and spatial aggregation of the native bunchgrass community. Landscape orientation and soil physical properties determined inherent risk to invasion. Resident bunchgrass and biological soil crust communities provided biotic resistance to invasion by reducing the size of and connectivity between basal gaps and thereby limiting available resources and reducing safe sites for B. tectorum establishment. High levels of cattle grazing reduced ecosystem resilience by reducing native bunchgrass and biological soil crust abundance and altering bunchgrass community composition and facilitated B. tectorum invasion. Conserving and restoring resilience and resistance of these imperiled ecosystems will require reducing cumulative stress levels. As global climate change increases heat and water stress, reducing cumulative cattle grazing intensities by altering utilization rates and/or seasons of use may be the only effective means of accomplishing these goals. Title: Drivers of plant community dynamics in sagebrush steppe ecosystems : cattle grazing, heat and water stress Author: Reisner, Michael D. Sagebrush steppe ecosystems are one of the most widespread but endangered ecosystems in North America. A diverse array of human-related stressors has gradually compromised these ecosystems' resilience to disturbance and invasion by Bromus tectorum (cheatgrass). The role of the foundational shrub Artemisia as a driver of herbaceous community structure and dynamics during this degradation process is poorly understood. Many of the individual factors driving B. tectorum invasions are well documented. However a predictive understanding of the relative importance of complex, interacting factors in the causal network of simultaneously occurring processes determining invasibility has proven elusive. I examined these issues at the landscape level across 75 sites capturing a range of soil and landscape properties and cattle grazing levels similar to those found across the Great Basin. Cumulative cattle herbivory stress levels were a predominant component of both the overlapping heat and water stress gradients driving the structure of Artemisia interactions with herbaceous species. Consistent with the stress gradient hypothesis, Artemisia facilitation of herbaceous species was most frequent and strongest at the highest stress levels, and competition was most frequent and strongest at the lowest stress levels. The two species with the highest competitive response abilities, Elymus elymoides and Poa secunda, showed the strongest facilitation at the upper limits of their stress tolerances. The structure of Artemisia interactions with the invasive B. tectorum was strikingly different than those with native bunchgrasses. Artemisia interactions with native bunchgrasses shifted from competition to facilitation with increasing heat, water, and herbivory stress, but its interactions remained competitive with B. tectorum along the entire stress gradient. Shifts in the structure of interactions between Artemisia and native bunchgrasses were associated with both an increase and decrease in community compositional and functional stability. I report the first evidence of native species facilitation decreasing community invasibility. Artemisia facilitation increased native bunchgrass composition, which reduced the magnitude of B. tectorum invasion in under-shrub compared to interspace communities. This decreased invasibility did not translate into lower invasibility at the community level because of the limited spatial scale over which such facilitation occurs. Artemisia facilitation increased community compositional and functional stability at intermediate stress levels but decreased community stability at high stress levels. Facilitation became a destabilizing force when native bunchgrass species became "obligate" beneficiaries, i.e. strongly dependent on Artemisia facilitation for their continued persistence in the community. Structural equation modeling assessed the structure of the causal network and relative importance of factors and processes predicted to drive community invasibility. The linchpin of ecosystem invasibility was the size of and connectivity between basal gaps in perennial vegetation, driven by shifts in the structure and spatial aggregation of the native bunchgrass community. Landscape orientation and soil physical properties determined inherent risk to invasion. Resident bunchgrass and biological soil crust communities provided biotic resistance to invasion by reducing the size of and connectivity between basal gaps and thereby limiting available resources and reducing safe sites for B. tectorum establishment. High levels of cattle grazing reduced ecosystem resilience by reducing native bunchgrass and biological soil crust abundance and altering bunchgrass community composition and facilitated B. tectorum invasion. Conserving and restoring resilience and resistance of these imperiled ecosystems will require reducing cumulative stress levels. As global climate change increases heat and water stress, reducing cumulative cattle grazing intensities by altering utilization rates and/or seasons of use may be the only effective means of accomplishing these goals. Close

• 28. [Article] Native wildlife species (Pseudacris regilla) utilizing invasive-dominated habitat in a highly disturbed ecosystem

  The Pacific Treefrog (Pseudacris regilla) is commonly encountered throughout the Pacific Northwest and can be an indicator for ecosystem health. At each life stage P. regilla utilizes a different habitat ...

  Citation × Citation Citation Abstract Copy Title: Native wildlife species (Pseudacris regilla) utilizing invasive-dominated habitat in a highly disturbed ecosystem Author: Epperly, Haley K. The Pacific Treefrog (Pseudacris regilla) is commonly encountered throughout the Pacific Northwest and can be an indicator for ecosystem health. At each life stage P. regilla utilizes a different habitat and therefore it is important to understand habitat use at all life stages to properly manage the ecosystem, however, few studies have been conducted on the juvenile form. To determine juvenile P. regilla riparian habitat use, and thus create appropriate habitat management plans, field work must be conducted. Transect surveys were conducted at two highly disturbed ephemeral ponds with a variety of open and dense vegetative riparian habitats in the Willamette Valley, Oregon. P. regilla was found in the highest abundance in habitat shaded by a thin border of Oregon Ash around the pond perimeter, and was composed mainly of Himalayan blackberry (Rubus armeniacus). This habitat provided a moist region where P. regilla could avoid desiccation and possibly predation. Rubus armeniacus is non-native and often found in highly disturbed ecosystems. Pseudacris regilla’s use of R. armeniacus as habitat suggests that P. regilla is a generalist species capable of utilizing invasive plant species to its advantage. Future research is needed comparing P. regilla habitat use in invasive-dominated verse native-dominated ephemeral ponds. Title: Native wildlife species (Pseudacris regilla) utilizing invasive-dominated habitat in a highly disturbed ecosystem Author: Epperly, Haley K. The Pacific Treefrog (Pseudacris regilla) is commonly encountered throughout the Pacific Northwest and can be an indicator for ecosystem health. At each life stage P. regilla utilizes a different habitat and therefore it is important to understand habitat use at all life stages to properly manage the ecosystem, however, few studies have been conducted on the juvenile form. To determine juvenile P. regilla riparian habitat use, and thus create appropriate habitat management plans, field work must be conducted. Transect surveys were conducted at two highly disturbed ephemeral ponds with a variety of open and dense vegetative riparian habitats in the Willamette Valley, Oregon. P. regilla was found in the highest abundance in habitat shaded by a thin border of Oregon Ash around the pond perimeter, and was composed mainly of Himalayan blackberry (Rubus armeniacus). This habitat provided a moist region where P. regilla could avoid desiccation and possibly predation. Rubus armeniacus is non-native and often found in highly disturbed ecosystems. Pseudacris regilla’s use of R. armeniacus as habitat suggests that P. regilla is a generalist species capable of utilizing invasive plant species to its advantage. Future research is needed comparing P. regilla habitat use in invasive-dominated verse native-dominated ephemeral ponds. Close

• 29. [Article] Non-Native Plant Invasion along Elevation and Canopy Closure Gradients in a Middle Rocky Mountain Ecosystem

  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 was published by the Public Library ...

  Citation × Citation Citation Abstract Copy Title: Non-Native Plant Invasion along Elevation and Canopy Closure Gradients in a Middle Rocky Mountain Ecosystem Author: Parks, Catherine G., DelCurto, Tim, Mata-González, Ricardo, Naylor, Bridgett J., McCune, Bruce, Averett, Joshua P. 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 was published by the Public Library of Science and is in the public domain. The published article can be found at: http://www.plosone.org/ Title: Non-Native Plant Invasion along Elevation and Canopy Closure Gradients in a Middle Rocky Mountain Ecosystem Author: Parks, Catherine G., DelCurto, Tim, Mata-González, Ricardo, Naylor, Bridgett J., McCune, Bruce, Averett, Joshua P. 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 was published by the Public Library of Science and is in the public domain. The published article can be found at: http://www.plosone.org/ Close

• 30. [Article] The potential of dynamic segmentation for aquatic ecosystem management : Pacific lamprey decline in the native lands of the Confederated Tribes of Siletz Indians (Oregon, USA)

  The Lamprey Eel Decline project conducted by the Confederated Tribes of Siletz Indians (CTSI) combined traditional ecological knowledge, scientific research and geographic information science. CTSI wanted ...

  Citation × Citation Citation Abstract Copy Title: The potential of dynamic segmentation for aquatic ecosystem management : Pacific lamprey decline in the native lands of the Confederated Tribes of Siletz Indians (Oregon, USA) Author: Palacios, Kelly C. The Lamprey Eel Decline project conducted by the Confederated Tribes of Siletz Indians (CTSI) combined traditional ecological knowledge, scientific research and geographic information science. CTSI wanted to learn why the Pacific lamprey (Lampetra tridentata), a culturally and ecologically important species, was declining in the streams within their native land area. The project included interviewing native elders, characterizing stream habitat, monitoring water quality, creating a geographic information system (GIS) and educating tribal members on the cultural and ecological importance of the Pacific lamprey. Dynamic segmentation, a GIS data structure, was used to link standard stream survey data on the river unit scale to a base stream coverage (1:24,000). Dynamic segmentation efficiently associates georeferenced data to a linear feature, thus allowing the data to be readily assessable on desktop computer systems. To be more useful to the tribal and local resource managers, it is recommended that these GIS coverages of aquatic habitat should be used in conjunction with additional data coverages and basic regional models for watershed analysis and better management of aquatic ecosystems. Title: The potential of dynamic segmentation for aquatic ecosystem management : Pacific lamprey decline in the native lands of the Confederated Tribes of Siletz Indians (Oregon, USA) Author: Palacios, Kelly C. The Lamprey Eel Decline project conducted by the Confederated Tribes of Siletz Indians (CTSI) combined traditional ecological knowledge, scientific research and geographic information science. CTSI wanted to learn why the Pacific lamprey (Lampetra tridentata), a culturally and ecologically important species, was declining in the streams within their native land area. The project included interviewing native elders, characterizing stream habitat, monitoring water quality, creating a geographic information system (GIS) and educating tribal members on the cultural and ecological importance of the Pacific lamprey. Dynamic segmentation, a GIS data structure, was used to link standard stream survey data on the river unit scale to a base stream coverage (1:24,000). Dynamic segmentation efficiently associates georeferenced data to a linear feature, thus allowing the data to be readily assessable on desktop computer systems. To be more useful to the tribal and local resource managers, it is recommended that these GIS coverages of aquatic habitat should be used in conjunction with additional data coverages and basic regional models for watershed analysis and better management of aquatic ecosystems. Close

• 31. [Article] Wolves and the Ecology of Fear: Can Predation Risk Structure Ecosystems?

  We investigated how large carnivores, herbivores, and plants may be linked to the maintenance of native species biodiversity through trophic cascades. The extirpation of wolves (Canis lupus) from Yellowstone ...

  Citation × Citation Citation Abstract Copy Title: Wolves and the Ecology of Fear: Can Predation Risk Structure Ecosystems? Author: Beschta, Robert L., Ripple, William J. We investigated how large carnivores, herbivores, and plants may be linked to the maintenance of native species biodiversity through trophic cascades. The extirpation of wolves (Canis lupus) from Yellowstone National Park in the mid-1920s and their reintroduction in 1995 provided the opportunity to examine the cascading effects of carnivore–herbivore interactions on woody browse species, as well as ecological responses involving riparian functions, beaver (Castor canadensis) populations, and general food webs. Our results indicate that predation risk may have profound effects on the structure of ecosystems and is an important constituent of native biodiversity. Our conclusions are based on theory involving trophic cascades, predation risk, and optimal foraging; on the research literature; and on our own recent studies in Yellowstone National Park. Additional research is needed to understand how the lethal effects of predation interact with its nonlethal effects to structure ecosystems. Title: Wolves and the Ecology of Fear: Can Predation Risk Structure Ecosystems? Author: Beschta, Robert L., Ripple, William J. We investigated how large carnivores, herbivores, and plants may be linked to the maintenance of native species biodiversity through trophic cascades. The extirpation of wolves (Canis lupus) from Yellowstone National Park in the mid-1920s and their reintroduction in 1995 provided the opportunity to examine the cascading effects of carnivore–herbivore interactions on woody browse species, as well as ecological responses involving riparian functions, beaver (Castor canadensis) populations, and general food webs. Our results indicate that predation risk may have profound effects on the structure of ecosystems and is an important constituent of native biodiversity. Our conclusions are based on theory involving trophic cascades, predation risk, and optimal foraging; on the research literature; and on our own recent studies in Yellowstone National Park. Additional research is needed to understand how the lethal effects of predation interact with its nonlethal effects to structure ecosystems. Close

• 32. [Article] Nitrogen limitation, 15N tracer retention, and growth response in intact and Bromus tectorum-invaded Artemisia tridentata ssp. wyomingensis communities

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

  Citation × Citation Citation Abstract Copy Title: Nitrogen limitation, 15N tracer retention, and growth response in intact and Bromus tectorum-invaded Artemisia tridentata ssp. wyomingensis communities Author: Doescher, Paul S., Perakis, Steven S., DeCrappeo, Nicole M., Witwicki, Dana L., Pyke, David A. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Springer and can be found at: http://www.springer.com/?SGWID=0-102-0-0-0. Title: Nitrogen limitation, 15N tracer retention, and growth response in intact and Bromus tectorum-invaded Artemisia tridentata ssp. wyomingensis communities Author: Doescher, Paul S., Perakis, Steven S., DeCrappeo, Nicole M., Witwicki, Dana L., Pyke, David A. To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The published article is copyrighted by Springer and can be found at: http://www.springer.com/?SGWID=0-102-0-0-0. Close

• 33. [Article] Controlling woody vegetation in wetland prairies, 1994-1999

  Wetland prairies of the Willamette Valley, among the rarest of Oregon’s ecosystems, are threatened by invasion of woody species and non-native pest species. Because fire has been important in maintaining ...

  Citation × Citation Citation Abstract Copy Title: Controlling woody vegetation in wetland prairies, 1994-1999 Author: Wilson, Mark V., Clark, Deborah Louise, 1950- Wetland prairies of the Willamette Valley, among the rarest of Oregon’s ecosystems, are threatened by invasion of woody species and non-native pest species. Because fire has been important in maintaining Willamette Valley prairies for at least 1000 years, prescribed burning is a top choice of managers for preventing encroachment of woody species. However, the effects of prescribed burning on present day wetland prairie communities, with their mix of native and non-native species, are not clear. Moreover, because strict governmental requirements for smoke management hinder prescribed burning, natural-area managers are considering alternatives to fire, like mowing and hand removal of woody plants. The present study explored the ecological interactions of a wetland prairie by experimentally testing the responses of burning, hand-removal of woody species, and mowing with removal of cut material on woody plants and key native and non-native grasses and forbs. We evaluated these perturbations for their effectiveness in meeting management objectives of reducing abundance of woody species, reducing or preventing an increase in abundance of nonnative pest species, and increasing or at least maintaining native species’ abundance. After three treatments periods (1994, 1996, and 1998) the following patterns emerged: • Woody species Burning and hand-removal consistently caused the greatest reduction in cover of woody species. Mowing with removal of cut material did not reduce the abundance of woody species compared to the control. As woody plant cover decreased, plant mortality increased, indicating that treatments influenced woody plant cover at least partially through changes in survival. • Native herbaceous species All management treatments consistently failed to significantly increase the cover of Deschampsia cespitosa, while burning decreased the number of inflorescences. As a group, native graminoid flowering consistently showed no significant responses to the management treatments. Although burning and hand-removal significantly increased the cover of native forbs as group after the second treatment period in 1997, native forbs showed no significant responses to treatments in 1999. • Non-native herbaceous species Response of non-native forb cover to management treatments has been inconsistent during the five year study period with no significant differences in 1995, significant reductions by burning and hand-removal in 1997, and increases with mowing in 1997. Mowing consistently increased flowering of nonnative graminoids as a group. Overall no treatment was clearly superior in fulfilling restoration objectives. Burning was effective in reducing woody cover and did not promote non-native herbaceous, but it reduced the flowering the dominant native grass, Deschampsia cespitosa. Hand-removal woody species was also effective at reducing woody cover and sometimes promoted the abundance of some native species at different times, but it also at times promoted non-native herbaceous species. Because mowing with removal of cut material was ineffective in reducing woody cover and tended to promote non-native herbaceous species, this treatment is not a recommended management strategy. Title: Controlling woody vegetation in wetland prairies, 1994-1999 Author: Wilson, Mark V., Clark, Deborah Louise, 1950- Wetland prairies of the Willamette Valley, among the rarest of Oregon’s ecosystems, are threatened by invasion of woody species and non-native pest species. Because fire has been important in maintaining Willamette Valley prairies for at least 1000 years, prescribed burning is a top choice of managers for preventing encroachment of woody species. However, the effects of prescribed burning on present day wetland prairie communities, with their mix of native and non-native species, are not clear. Moreover, because strict governmental requirements for smoke management hinder prescribed burning, natural-area managers are considering alternatives to fire, like mowing and hand removal of woody plants. The present study explored the ecological interactions of a wetland prairie by experimentally testing the responses of burning, hand-removal of woody species, and mowing with removal of cut material on woody plants and key native and non-native grasses and forbs. We evaluated these perturbations for their effectiveness in meeting management objectives of reducing abundance of woody species, reducing or preventing an increase in abundance of nonnative pest species, and increasing or at least maintaining native species’ abundance. After three treatments periods (1994, 1996, and 1998) the following patterns emerged: • Woody species Burning and hand-removal consistently caused the greatest reduction in cover of woody species. Mowing with removal of cut material did not reduce the abundance of woody species compared to the control. As woody plant cover decreased, plant mortality increased, indicating that treatments influenced woody plant cover at least partially through changes in survival. • Native herbaceous species All management treatments consistently failed to significantly increase the cover of Deschampsia cespitosa, while burning decreased the number of inflorescences. As a group, native graminoid flowering consistently showed no significant responses to the management treatments. Although burning and hand-removal significantly increased the cover of native forbs as group after the second treatment period in 1997, native forbs showed no significant responses to treatments in 1999. • Non-native herbaceous species Response of non-native forb cover to management treatments has been inconsistent during the five year study period with no significant differences in 1995, significant reductions by burning and hand-removal in 1997, and increases with mowing in 1997. Mowing consistently increased flowering of nonnative graminoids as a group. Overall no treatment was clearly superior in fulfilling restoration objectives. Burning was effective in reducing woody cover and did not promote non-native herbaceous, but it reduced the flowering the dominant native grass, Deschampsia cespitosa. Hand-removal woody species was also effective at reducing woody cover and sometimes promoted the abundance of some native species at different times, but it also at times promoted non-native herbaceous species. Because mowing with removal of cut material was ineffective in reducing woody cover and tended to promote non-native herbaceous species, this treatment is not a recommended management strategy. Close

• 34. [Article] Controlling woody vegetation in wetland prairies, 1994-2001

  Wetland prairies of the Willamette Valley, among the rarest of Oregon’s ecosystems, are threatened by invasion of woody species and non-native pest species. Because fire has been important in maintaining ...

  Citation × Citation Citation Abstract Copy Title: Controlling woody vegetation in wetland prairies, 1994-2001 Author: Clark, Deborah Louise, 1950- Wetland prairies of the Willamette Valley, among the rarest of Oregon’s ecosystems, are threatened by invasion of woody species and non-native pest species. Because fire has been important in maintaining Willamette Valley prairies for at least 1000 years, prescribed burning is a top choice of managers for preventing encroachment of woody species. However, the effects of prescribed burning on present day wetland prairie communities, with their mix of native and non-native species, are not clear. Moreover, because strict governmental requirements for smoke management hinder prescribed burning, natural-area managers are considering alternatives to fire, like mowing and hand-removal of woody plants. The present study explored the ecological interactions of a wetland prairie by experimentally testing the responses of burning, hand-removal of woody species, and mowing with removal of cut material on woody plants and key native and non-native grasses and forbs. We evaluated these perturbations for their effectiveness in meeting management objectives of reducing abundance of woody species, reducing or preventing an increase in abundance of nonnative pest species, and increasing or at least maintaining native species’ abundance. After four treatments periods (1994, 1996, 1998, and 2000) the following patterns emerged: • Woody species Burning and hand-removal of woody plants every two years consistently decreased the cover of woody species, even with a gradual increase in the controls to over double 1994 levels. The change in woody cover after mowing with removal of cut material was not significantly different from that in the control. As woody plant cover decreased, plant mortality increased, indicating that treatments influenced woody plant cover at least partially through changes in survival. • Native herbaceous species None of the treatments had a significant effect after four treatment periods on the proportional change in cover or in number of inflorescences of Deschampsia cespitosa, although the change in number of inflorescences was consistently less than that in the control, including a significant decrease with burning in 1997. As a group, native graminoid species showed no significant differences in flowering response to treatments during any of the four treatment periods. However, burning and mowing consistently promoted flowering of Juncus tenuis. The cover of native forbs as a group was not significantly different from that of the control, with the exception of 1997, where cover increased with burning and hand-removal. Even though native forbs as a group have generally not shown significant differences, individual native forb species have shown positive responses to treatments: Sidalcea cusickii, spp. purpurea, Eriophyllum lanatum, and Sisyrinchium idahoensis. • Non-native herbaceous species Both hand-removal and mowing promoted flowering of non-native graminoids as a group. In contrast, burning maintained levels of flowering of non-native graminoids similar to that of the controls. Cover of non-native forbs as a group showed no significant treatment differences except for 1997, in which significant reductions in cover occurred after burning and hand-removal. The results to date show that prescribed burning is the best option of the three tested management treatments for achieving the restoration goals for native wetland prairies. Because mowing with removal of cut material was ineffective in reducing woody cover and tended to promote non-native herbaceous species, this treatment should be avoided. Title: Controlling woody vegetation in wetland prairies, 1994-2001 Author: Clark, Deborah Louise, 1950- Wetland prairies of the Willamette Valley, among the rarest of Oregon’s ecosystems, are threatened by invasion of woody species and non-native pest species. Because fire has been important in maintaining Willamette Valley prairies for at least 1000 years, prescribed burning is a top choice of managers for preventing encroachment of woody species. However, the effects of prescribed burning on present day wetland prairie communities, with their mix of native and non-native species, are not clear. Moreover, because strict governmental requirements for smoke management hinder prescribed burning, natural-area managers are considering alternatives to fire, like mowing and hand-removal of woody plants. The present study explored the ecological interactions of a wetland prairie by experimentally testing the responses of burning, hand-removal of woody species, and mowing with removal of cut material on woody plants and key native and non-native grasses and forbs. We evaluated these perturbations for their effectiveness in meeting management objectives of reducing abundance of woody species, reducing or preventing an increase in abundance of nonnative pest species, and increasing or at least maintaining native species’ abundance. After four treatments periods (1994, 1996, 1998, and 2000) the following patterns emerged: • Woody species Burning and hand-removal of woody plants every two years consistently decreased the cover of woody species, even with a gradual increase in the controls to over double 1994 levels. The change in woody cover after mowing with removal of cut material was not significantly different from that in the control. As woody plant cover decreased, plant mortality increased, indicating that treatments influenced woody plant cover at least partially through changes in survival. • Native herbaceous species None of the treatments had a significant effect after four treatment periods on the proportional change in cover or in number of inflorescences of Deschampsia cespitosa, although the change in number of inflorescences was consistently less than that in the control, including a significant decrease with burning in 1997. As a group, native graminoid species showed no significant differences in flowering response to treatments during any of the four treatment periods. However, burning and mowing consistently promoted flowering of Juncus tenuis. The cover of native forbs as a group was not significantly different from that of the control, with the exception of 1997, where cover increased with burning and hand-removal. Even though native forbs as a group have generally not shown significant differences, individual native forb species have shown positive responses to treatments: Sidalcea cusickii, spp. purpurea, Eriophyllum lanatum, and Sisyrinchium idahoensis. • Non-native herbaceous species Both hand-removal and mowing promoted flowering of non-native graminoids as a group. In contrast, burning maintained levels of flowering of non-native graminoids similar to that of the controls. Cover of non-native forbs as a group showed no significant treatment differences except for 1997, in which significant reductions in cover occurred after burning and hand-removal. The results to date show that prescribed burning is the best option of the three tested management treatments for achieving the restoration goals for native wetland prairies. Because mowing with removal of cut material was ineffective in reducing woody cover and tended to promote non-native herbaceous species, this treatment should be avoided. Close

• 35. [Article] The Potential of dynamic segmentation for aquatic ecosystem management : Pacific Lamprey decline in the native lands of the Confederated Tribes of Siletz Indians

  The Lamprey Eel Decline project conducted by the Confederated Tribes of Siletz Indians (CTSI) combined traditional ecological knowledge, scientific research and geographic information science. CTSI wanted ...

  Citation × Citation Citation Abstract Copy Title: The Potential of dynamic segmentation for aquatic ecosystem management : Pacific Lamprey decline in the native lands of the Confederated Tribes of Siletz Indians Author: Palacios, Kelly C. The Lamprey Eel Decline project conducted by the Confederated Tribes of Siletz Indians (CTSI) combined traditional ecological knowledge, scientific research and geographic information science. CTSI wanted to learn why the Pacific lamprey (Lampetra tridentata), a culturally and ecologically important species, was declining in the streams within their native land area. The project included interviewing native elders, characterizing stream habitat, monitoring water quality, creating a geographic information system (GIS) and educating tribal members on the cultural and ecological importance of the Pacific lamprey. Dynamic segmentation, a GIS data structure, was used to link standard stream survey data on the river unit scale to a base stream coverage (1:24,000). Dynamic segmentation efficiently associates georeferenced data to a linear feature, thus allowing the data to be readily assessable on desktop computer systems. To be more useful to the tribal and local resource managers, it is recommended that these GIS coverages of aquatic habitat should be used in conjunction with additional data coverages and basic regional models for watershed analysis and better management of aquatic ecosystems. Title: The Potential of dynamic segmentation for aquatic ecosystem management : Pacific Lamprey decline in the native lands of the Confederated Tribes of Siletz Indians Author: Palacios, Kelly C. The Lamprey Eel Decline project conducted by the Confederated Tribes of Siletz Indians (CTSI) combined traditional ecological knowledge, scientific research and geographic information science. CTSI wanted to learn why the Pacific lamprey (Lampetra tridentata), a culturally and ecologically important species, was declining in the streams within their native land area. The project included interviewing native elders, characterizing stream habitat, monitoring water quality, creating a geographic information system (GIS) and educating tribal members on the cultural and ecological importance of the Pacific lamprey. Dynamic segmentation, a GIS data structure, was used to link standard stream survey data on the river unit scale to a base stream coverage (1:24,000). Dynamic segmentation efficiently associates georeferenced data to a linear feature, thus allowing the data to be readily assessable on desktop computer systems. To be more useful to the tribal and local resource managers, it is recommended that these GIS coverages of aquatic habitat should be used in conjunction with additional data coverages and basic regional models for watershed analysis and better management of aquatic ecosystems. Close

• 36. [Article] Contrasting distribution patterns of invasive and naturalized non-native species along environmental gradients in a semi-arid montane ecosystem

  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 International Association ...

  Citation × Citation Citation Abstract Copy Title: Contrasting distribution patterns of invasive and naturalized non-native species along environmental gradients in a semi-arid montane ecosystem Author: Andersen, Kelly M., Endress, Bryan A., Parks, Catherine G., Naylor, Bridgett J. 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 International Association for Vegetation Science and published by John Wiley & Sons, Ltd.. It can be found at: http://onlinelibrary.wiley.com/journal/10.1111/%28ISSN%291654-109X Title: Contrasting distribution patterns of invasive and naturalized non-native species along environmental gradients in a semi-arid montane ecosystem Author: Andersen, Kelly M., Endress, Bryan A., Parks, Catherine G., Naylor, Bridgett J. 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 International Association for Vegetation Science and published by John Wiley & Sons, Ltd.. It can be found at: http://onlinelibrary.wiley.com/journal/10.1111/%28ISSN%291654-109X Close

• 37. [Article] Investigating temporal patterns of a native bee community in a remnant North American bunchgrass prairie using blue vane traps

  This is the publisher’s final pdf. The published article is copyrighted by University of Wisconsin Digital Collections Center and can be found at: http://www.insectscience.org/.

  Citation × Citation Citation Abstract Copy Title: Investigating temporal patterns of a native bee community in a remnant North American bunchgrass prairie using blue vane traps Author: Rao, Sujaya, Stephen, William P., Kimoto, Chiho, Thorp, Robbin W., DeBano, Sandra J. This is the publisher’s final pdf. The published article is copyrighted by University of Wisconsin Digital Collections Center and can be found at: http://www.insectscience.org/. Title: Investigating temporal patterns of a native bee community in a remnant North American bunchgrass prairie using blue vane traps Author: Rao, Sujaya, Stephen, William P., Kimoto, Chiho, Thorp, Robbin W., DeBano, Sandra J. This is the publisher’s final pdf. The published article is copyrighted by University of Wisconsin Digital Collections Center and can be found at: http://www.insectscience.org/. Close

• 38. [Article] Re-examining the relationship between invasive lionfish and native grouper in the Caribbean

  This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by PeerJ. The published article can be found at: https://peerj.com/.

  Citation × Citation Citation Abstract Copy Title: Re-examining the relationship between invasive lionfish and native grouper in the Caribbean Author: Hackerott, Serena, Valdivia, Abel, Bruno, John F., Cox, Courtney E., Green, Stephanie J. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by PeerJ. The published article can be found at: https://peerj.com/. Title: Re-examining the relationship between invasive lionfish and native grouper in the Caribbean Author: Hackerott, Serena, Valdivia, Abel, Bruno, John F., Cox, Courtney E., Green, Stephanie J. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by PeerJ. The published article can be found at: https://peerj.com/. Close

• 39. [Article] Butterfly and flower community composition among prairie-oak ecosystem habitats in the Willamette Valley, Oregon

  Prairie-oak ecosystems in the Willamette Valley, Oregon have experienced habitat loss and degradation; most of these ecosystems are fragmented into smaller patches. Prairie-oak butterfly species, in the ...

  Citation × Citation Citation Abstract Copy Title: Butterfly and flower community composition among prairie-oak ecosystem habitats in the Willamette Valley, Oregon Author: Powers, Breanna F. Prairie-oak ecosystems in the Willamette Valley, Oregon have experienced habitat loss and degradation; most of these ecosystems are fragmented into smaller patches. Prairie-oak butterfly species, in the Willamette Valley, have decreased dramatically due to loss or degradation of habitat. More research is needed on sustaining the populations of butterflies in prairie-oak ecosystems. The purpose of my study was to examine the role prairie-oak habitats have in structuring butterfly communities in the Willamette Valley. My objectives were to: (1) assess how butterfly community structure and species composition (density, abundance, and species richness) varies along an oak canopy cover gradient in order to understand the role of habitat type in structuring butterfly communities in prairie-oak ecosystems; (2) characterize community composition of nectar resources and environmental variables known to be important for butterfly species. I also investigated temporal and structural relationships between butterfly and flower communities. I found that butterfly abundance and density were greater (p < 0.02) in prairies than in oak savannas or oak woodlands; however, species richness did not differ among habitats (p = 0.54). Ordination of prairie-oak habitats in butterfly species space with a joint plot overlay of environmental variables revealed several strong correlations; butterfly community structure was negatively correlated with litter and oak canopy cover and positively correlated to vegetation cover. The prairie, oak savanna, and oak woodland habitat types differed in nectar species community structure, though this difference was small. Non-native species were some of the most abundant flowers species found in all stands. Butterfly communities were positively related to flower communities. I detected significant seasonal patterns among the habitat types in butterfly and flower communities. Prairies appear to be the most important habitat for native butterfly populations compared to oak savanna and oak woodlands. Flowers were most prevalent in prairies and prairies had the highest percentage of native flower species; the prevalence of non-native flower species was greatest in oak woodlands. My study may represent a short-term community transition as a result of management or it may represent a more permanent community. Further study is needed to understand the effects of different management strategies for habitat restoration and the presence of non-native flower species on butterflies in prairie-oak ecosystems in the Willamette Valley. Title: Butterfly and flower community composition among prairie-oak ecosystem habitats in the Willamette Valley, Oregon Author: Powers, Breanna F. Prairie-oak ecosystems in the Willamette Valley, Oregon have experienced habitat loss and degradation; most of these ecosystems are fragmented into smaller patches. Prairie-oak butterfly species, in the Willamette Valley, have decreased dramatically due to loss or degradation of habitat. More research is needed on sustaining the populations of butterflies in prairie-oak ecosystems. The purpose of my study was to examine the role prairie-oak habitats have in structuring butterfly communities in the Willamette Valley. My objectives were to: (1) assess how butterfly community structure and species composition (density, abundance, and species richness) varies along an oak canopy cover gradient in order to understand the role of habitat type in structuring butterfly communities in prairie-oak ecosystems; (2) characterize community composition of nectar resources and environmental variables known to be important for butterfly species. I also investigated temporal and structural relationships between butterfly and flower communities. I found that butterfly abundance and density were greater (p < 0.02) in prairies than in oak savannas or oak woodlands; however, species richness did not differ among habitats (p = 0.54). Ordination of prairie-oak habitats in butterfly species space with a joint plot overlay of environmental variables revealed several strong correlations; butterfly community structure was negatively correlated with litter and oak canopy cover and positively correlated to vegetation cover. The prairie, oak savanna, and oak woodland habitat types differed in nectar species community structure, though this difference was small. Non-native species were some of the most abundant flowers species found in all stands. Butterfly communities were positively related to flower communities. I detected significant seasonal patterns among the habitat types in butterfly and flower communities. Prairies appear to be the most important habitat for native butterfly populations compared to oak savanna and oak woodlands. Flowers were most prevalent in prairies and prairies had the highest percentage of native flower species; the prevalence of non-native flower species was greatest in oak woodlands. My study may represent a short-term community transition as a result of management or it may represent a more permanent community. Further study is needed to understand the effects of different management strategies for habitat restoration and the presence of non-native flower species on butterflies in prairie-oak ecosystems in the Willamette Valley. Close

• 40. [Article] Quantifying the Potential of Native Plants for Improving Pollination and Biological Control in Agroecosystems

  Agricultural areas can be inhospitable to the attraction and maintenance of beneficial insects like natural enemies and pollinators and this can result in a decrease in the ecosystem services of pollination ...

  Citation × Citation Citation Abstract Copy Title: Quantifying the Potential of Native Plants for Improving Pollination and Biological Control in Agroecosystems Author: Winfield, Tammy L. Agricultural areas can be inhospitable to the attraction and maintenance of beneficial insects like natural enemies and pollinators and this can result in a decrease in the ecosystem services of pollination and pest control that these insects supply. If habitat can be created and maintained on-farm, an increase in the numbers and diversity of beneficial insects could be seen which could correspond to an increase in ecosystem services. This study was undertaken to quantify what insect communities are supported by a set of native Oregon plants and to test for differences in the relative attractiveness of plant species to three broad categories of insects: herbivores, natural enemies, and pollinators. This first season of research shows that plant species vary in their relative attractiveness to the three functional groups of insects. Some of this variation is likely related to differences in flowering phenology. There was a significant positive association between percent peak bloom and the number of natural enemies collected on a particular plant species. The numbers of natural enemies, herbivores, and pollinators collected on plant species also varied across sites, suggesting that landscape characteristics also influence the insect communities associated with particular plant species. Title: Quantifying the Potential of Native Plants for Improving Pollination and Biological Control in Agroecosystems Author: Winfield, Tammy L. Agricultural areas can be inhospitable to the attraction and maintenance of beneficial insects like natural enemies and pollinators and this can result in a decrease in the ecosystem services of pollination and pest control that these insects supply. If habitat can be created and maintained on-farm, an increase in the numbers and diversity of beneficial insects could be seen which could correspond to an increase in ecosystem services. This study was undertaken to quantify what insect communities are supported by a set of native Oregon plants and to test for differences in the relative attractiveness of plant species to three broad categories of insects: herbivores, natural enemies, and pollinators. This first season of research shows that plant species vary in their relative attractiveness to the three functional groups of insects. Some of this variation is likely related to differences in flowering phenology. There was a significant positive association between percent peak bloom and the number of natural enemies collected on a particular plant species. The numbers of natural enemies, herbivores, and pollinators collected on plant species also varied across sites, suggesting that landscape characteristics also influence the insect communities associated with particular plant species. Close

• 41. [Article] Non-native and native plant species distributions and variability along an elevation gradient in the Wallowa Mountains, Oregon

  Invasion by non-native plants into natural areas is an important component of global change that threatens biodiversity and ecosystem structure and function. Mountains are currently among the least invaded ...

  Citation × Citation Citation Abstract Copy Title: Non-native and native plant species distributions and variability along an elevation gradient in the Wallowa Mountains, Oregon Author: Averett, Joshua P. Invasion by non-native plants into natural areas is an important component of global change that threatens biodiversity and ecosystem structure and function. Mountains are currently among the least invaded ecosystems, however, these biodiversity hotspots are increasingly under threat of exotic plant invasion. Evaluation of plant species distribution patterns in mountain ecosystems can provide insight into dominant processes of plant invasion and inform management to reduce the spread of non-native plants in mountains. The objectives of this study were to: 1) evaluate the main drivers of plant invasions in the Wallowa Mountain Range of northeastern Oregon, and the extent patterns of native species distributions and their causes differed from non-native species along an elevation gradient; and 2) investigate inter- and intra-annual understory vascular plant species variability along an elevation gradient to inform long-term monitoring of plant invasion dynamics in the Wallowa Mountains. We sampled understory vascular plant communities in summer 2012 along three forest roads in the Wallowa Mountains. Transects (n=20) were evenly stratified by elevation (60 meters) along each road. Indicator species analysis (ISA) was used to identify habitat tendencies for non-native species. Non-metric multidimensional scaling (NMS) related community composition to environmental and species trait factors. Predictors of non-native and native species abundance and richness were evaluated using Non-parametric multiplicative regression (NPMR). Canopy openness and elevation niche widths were modeled for all common species and evaluated for evidence of high elevation or closed canopy specialization. Non-native species richness decreased continuously with increasing elevation. In contrast, native species richness displayed a unimodal distribution with maximum richness at the mid-elevations. According to NMS and NPMR, elevation, canopy openness, and disturbance were the strongest correlates of non-native species abundance. Non-native species were concentrated in low elevation bunchgrass, roadside, and open forest habitats with high canopy openness, and moderate to high disturbance intensity. Overlays of species trait factors onto ordinations revealed that the transition into the subalpine community and over-story canopy closure exceeding approximately 60 percent were potential barriers to non-native species establishment. Vegetation sampling was repeated three times (June, July, and August 2013) during the growing season in summer 2013 for a subset (n=10) of our transects. Blocked Multi Response Permutation Procedure (MRBP) was used to test the hypothesis of no change in species composition between years (summer 2012 and summer 2013) and between each sampling period (June, July, and August) within one growing season. NMS related community composition at different times to environmental and trait category factors. Blocked Indicator Species Analysis was used to identify species with tendencies towards specific sampling periods. Important predictors of vegetation change were identified and indicator species distributions were related to NMS axes using NPMR. Vegetation composition changed both between years and between each sampling period within one growing season. Species richness increased with sampling effort, dominant species were consistently found throughout all sampling periods and rare species showed the highest rate of turnover between sampling periods. The highest species richness and greatest number of indicator species were associated with the early summer (June) sampling period. Approximately 25% of all non-native species showed tendencies towards a specific sampling period where greater than half favored the June sampling period within lowland bunchgrass communities. Annual species including the most dominant non-native species within the lowland and montane zones showed the highest inter- and intra-annual variability compared to other trait categories. Total species richness was positively related to turnover and was the most important predictor of relative abundance change between all sampling periods. Species turnover was highest in species rich montane plots; however, trait abundance and richness did not statistically differ in montane plots. These data suggest that elevation, canopy, openness, and disturbance are important factors structuring non-native plant distributions in the Wallowa Mountains. Our findings that non-native species tended to be concentrated in low elevation, early successional habitats coupled with a lack of high elevation or closed canopy specialization indicates that non-native plants that occurr at the highest elevations are likely generalist species that depend on disturbance (primarily open over-story canopy) for spread into higher elevation sites until they are eventually filtered out by harsh environmental conditions coincident with the subalpine transition zone. Collectively these results suggest that interactions between introduction pathways that favor human assisted dispersal into the low-elevations where ruderal species are favored and environmental filters (elevation, canopy openness, and disturbance) are the dominant factors structuring non-native plant distributions in the Wallowa Mountains. Our results also indicate that long-term monitoring of vegetation change in the Wallowa Mountains will be improved through periodic sampling during each growing season. Sampling once during the spring or early summer and then again coincident with peak biomass should improve estimates of species distributions and diversity patterns by capturing both vernal and late season species. Early season sampling may be particularly important for monitoring non-native plants in the Wallowa Mountains as most non-natives were concentrated in low elevation semiarid bunchgrass communities where spring and early summer specialization is common. Title: Non-native and native plant species distributions and variability along an elevation gradient in the Wallowa Mountains, Oregon Author: Averett, Joshua P. Invasion by non-native plants into natural areas is an important component of global change that threatens biodiversity and ecosystem structure and function. Mountains are currently among the least invaded ecosystems, however, these biodiversity hotspots are increasingly under threat of exotic plant invasion. Evaluation of plant species distribution patterns in mountain ecosystems can provide insight into dominant processes of plant invasion and inform management to reduce the spread of non-native plants in mountains. The objectives of this study were to: 1) evaluate the main drivers of plant invasions in the Wallowa Mountain Range of northeastern Oregon, and the extent patterns of native species distributions and their causes differed from non-native species along an elevation gradient; and 2) investigate inter- and intra-annual understory vascular plant species variability along an elevation gradient to inform long-term monitoring of plant invasion dynamics in the Wallowa Mountains. We sampled understory vascular plant communities in summer 2012 along three forest roads in the Wallowa Mountains. Transects (n=20) were evenly stratified by elevation (60 meters) along each road. Indicator species analysis (ISA) was used to identify habitat tendencies for non-native species. Non-metric multidimensional scaling (NMS) related community composition to environmental and species trait factors. Predictors of non-native and native species abundance and richness were evaluated using Non-parametric multiplicative regression (NPMR). Canopy openness and elevation niche widths were modeled for all common species and evaluated for evidence of high elevation or closed canopy specialization. Non-native species richness decreased continuously with increasing elevation. In contrast, native species richness displayed a unimodal distribution with maximum richness at the mid-elevations. According to NMS and NPMR, elevation, canopy openness, and disturbance were the strongest correlates of non-native species abundance. Non-native species were concentrated in low elevation bunchgrass, roadside, and open forest habitats with high canopy openness, and moderate to high disturbance intensity. Overlays of species trait factors onto ordinations revealed that the transition into the subalpine community and over-story canopy closure exceeding approximately 60 percent were potential barriers to non-native species establishment. Vegetation sampling was repeated three times (June, July, and August 2013) during the growing season in summer 2013 for a subset (n=10) of our transects. Blocked Multi Response Permutation Procedure (MRBP) was used to test the hypothesis of no change in species composition between years (summer 2012 and summer 2013) and between each sampling period (June, July, and August) within one growing season. NMS related community composition at different times to environmental and trait category factors. Blocked Indicator Species Analysis was used to identify species with tendencies towards specific sampling periods. Important predictors of vegetation change were identified and indicator species distributions were related to NMS axes using NPMR. Vegetation composition changed both between years and between each sampling period within one growing season. Species richness increased with sampling effort, dominant species were consistently found throughout all sampling periods and rare species showed the highest rate of turnover between sampling periods. The highest species richness and greatest number of indicator species were associated with the early summer (June) sampling period. Approximately 25% of all non-native species showed tendencies towards a specific sampling period where greater than half favored the June sampling period within lowland bunchgrass communities. Annual species including the most dominant non-native species within the lowland and montane zones showed the highest inter- and intra-annual variability compared to other trait categories. Total species richness was positively related to turnover and was the most important predictor of relative abundance change between all sampling periods. Species turnover was highest in species rich montane plots; however, trait abundance and richness did not statistically differ in montane plots. These data suggest that elevation, canopy, openness, and disturbance are important factors structuring non-native plant distributions in the Wallowa Mountains. Our findings that non-native species tended to be concentrated in low elevation, early successional habitats coupled with a lack of high elevation or closed canopy specialization indicates that non-native plants that occurr at the highest elevations are likely generalist species that depend on disturbance (primarily open over-story canopy) for spread into higher elevation sites until they are eventually filtered out by harsh environmental conditions coincident with the subalpine transition zone. Collectively these results suggest that interactions between introduction pathways that favor human assisted dispersal into the low-elevations where ruderal species are favored and environmental filters (elevation, canopy openness, and disturbance) are the dominant factors structuring non-native plant distributions in the Wallowa Mountains. Our results also indicate that long-term monitoring of vegetation change in the Wallowa Mountains will be improved through periodic sampling during each growing season. Sampling once during the spring or early summer and then again coincident with peak biomass should improve estimates of species distributions and diversity patterns by capturing both vernal and late season species. Early season sampling may be particularly important for monitoring non-native plants in the Wallowa Mountains as most non-natives were concentrated in low elevation semiarid bunchgrass communities where spring and early summer specialization is common. Close

• 42. [Article] The influence of biophysical feedbacks and species interactions on grass invasions and coastal dune morphology in the Pacific Northwest, USA

  Biological invasions provide a unique opportunity to study the mechanisms that regulate community composition and ecosystem function. Invasive species that are also ecosystem engineers can substantially ...

  Citation × Citation Citation Abstract Copy Title: The influence of biophysical feedbacks and species interactions on grass invasions and coastal dune morphology in the Pacific Northwest, USA Author: Zarnetske, Phoebe Lehmann, 1979- Biological invasions provide a unique opportunity to study the mechanisms that regulate community composition and ecosystem function. Invasive species that are also ecosystem engineers can substantially alter physical features in an environment, and this can lead to cascading effects on the biological community. Aquatic-terrestrial interface ecosystems are excellent systems to study the interactions among invasive ecosystem engineers, physical features, and biological communities, because interactions among vegetation, sediment, and fluids within biophysical feedbacks create and modify distinct physical features. Further, these systems provide important ecosystem services including coastal protection afforded by their natural features. In this dissertation, I investigate the interactions and feedbacks among sand-binding beach grass species (a native, Elymus mollis (Trin.), and two non-natives, Ammophila arenaria (L.) Link and A. breviligulata Fernald), sediment supply, and dune shape along the U.S. Pacific Northwest coast. Dunes dominated by A. arenaria tend to be taller and narrower compared to the shorter, wider dunes dominated by A. breviligulata. These patterns suggest an ecological control on dune shape, and thus, coastal vulnerability to overtopping waves. I investigate the causes and consequences of these patterns with experiments, field observations, and modeling. Specifically, I investigate the relative roles of vegetation and sediment supply in shaping coastal dunes over inter-annual and multi-decadal time scales (Chapter 2), characterize a biophysical feedback between beach grass species growth habit and sediment supply (Chapter 3), uncover the mechanisms leading to beach grass coexistence and whether A. breviligulata can invade and dominate new sections of coastline (Chapter 4), and examine the non-target effects resulting from management actions that remove Ammophila for the recovery of the threatened Western Snowy plover (Charadrius alexandrinus nivosus) (Chapter 5). I found that vegetation and sediment supply play important roles in dune shape changes across inter-annual and multi-decadal time scales (Chapter 2). I determined that a biophysical feedback between the beach grass growth habits and sediment supply results in species-specific differences in sand capture ability, and thus, is a likely explanation for differences in dune shape (Chapter 3). I found that all three beach grass species can coexist across different sediment deposition rates, and that this coexistence is largely mediated by positive direct and indirect species interactions. I further determined that A. breviligulata is capable of invading and dominating the beach grass community in regions where it is currently absent (Chapter 4). Combined, these findings indicate that A. breviligulata is an inferior dune building species as compared to A. arenaria, and suggest that in combination with sediment supply gradients, these species differences ultimately lead to differences in dune shape. Potential further invasions of A. breviligulata into southern regions of the Pacific Northwest may diminish the coastal protection ability of dunes currently dominated by A. arenaria, but this effect could be moderated by the predicted near co-dominance of A. arenaria in these lower sediment supply conditions. Finally, I found that the techniques used to remove Ammophila for plover recovery have unintended consequences for the native and endemic dune plant communities, and disrupt the natural disturbance regime of shifting sand. A whole-ecosystem restoration focus would be an improvement over the target-species approach, as it would promote the return of the natural disturbance regime, which in turn, would help recover the native biological community. The findings from this dissertation research provide a robust knowledge base that can guide further investigations of biological and physical changes to the coastal dunes, can help improve the management of dune ecosystem services and the restoration of native communities, and can help anticipate the impacts of future beach grass invasions and climate change induced changes to the coast. Title: The influence of biophysical feedbacks and species interactions on grass invasions and coastal dune morphology in the Pacific Northwest, USA Author: Zarnetske, Phoebe Lehmann, 1979- Biological invasions provide a unique opportunity to study the mechanisms that regulate community composition and ecosystem function. Invasive species that are also ecosystem engineers can substantially alter physical features in an environment, and this can lead to cascading effects on the biological community. Aquatic-terrestrial interface ecosystems are excellent systems to study the interactions among invasive ecosystem engineers, physical features, and biological communities, because interactions among vegetation, sediment, and fluids within biophysical feedbacks create and modify distinct physical features. Further, these systems provide important ecosystem services including coastal protection afforded by their natural features. In this dissertation, I investigate the interactions and feedbacks among sand-binding beach grass species (a native, Elymus mollis (Trin.), and two non-natives, Ammophila arenaria (L.) Link and A. breviligulata Fernald), sediment supply, and dune shape along the U.S. Pacific Northwest coast. Dunes dominated by A. arenaria tend to be taller and narrower compared to the shorter, wider dunes dominated by A. breviligulata. These patterns suggest an ecological control on dune shape, and thus, coastal vulnerability to overtopping waves. I investigate the causes and consequences of these patterns with experiments, field observations, and modeling. Specifically, I investigate the relative roles of vegetation and sediment supply in shaping coastal dunes over inter-annual and multi-decadal time scales (Chapter 2), characterize a biophysical feedback between beach grass species growth habit and sediment supply (Chapter 3), uncover the mechanisms leading to beach grass coexistence and whether A. breviligulata can invade and dominate new sections of coastline (Chapter 4), and examine the non-target effects resulting from management actions that remove Ammophila for the recovery of the threatened Western Snowy plover (Charadrius alexandrinus nivosus) (Chapter 5). I found that vegetation and sediment supply play important roles in dune shape changes across inter-annual and multi-decadal time scales (Chapter 2). I determined that a biophysical feedback between the beach grass growth habits and sediment supply results in species-specific differences in sand capture ability, and thus, is a likely explanation for differences in dune shape (Chapter 3). I found that all three beach grass species can coexist across different sediment deposition rates, and that this coexistence is largely mediated by positive direct and indirect species interactions. I further determined that A. breviligulata is capable of invading and dominating the beach grass community in regions where it is currently absent (Chapter 4). Combined, these findings indicate that A. breviligulata is an inferior dune building species as compared to A. arenaria, and suggest that in combination with sediment supply gradients, these species differences ultimately lead to differences in dune shape. Potential further invasions of A. breviligulata into southern regions of the Pacific Northwest may diminish the coastal protection ability of dunes currently dominated by A. arenaria, but this effect could be moderated by the predicted near co-dominance of A. arenaria in these lower sediment supply conditions. Finally, I found that the techniques used to remove Ammophila for plover recovery have unintended consequences for the native and endemic dune plant communities, and disrupt the natural disturbance regime of shifting sand. A whole-ecosystem restoration focus would be an improvement over the target-species approach, as it would promote the return of the natural disturbance regime, which in turn, would help recover the native biological community. The findings from this dissertation research provide a robust knowledge base that can guide further investigations of biological and physical changes to the coastal dunes, can help improve the management of dune ecosystem services and the restoration of native communities, and can help anticipate the impacts of future beach grass invasions and climate change induced changes to the coast. Close

• 43. [Article] Ecosystem services provided by Olympia oyster (Ostrea lurida) habitat and Pacific oyster (Crassostrea gigas) habitat; Dungeness crab (Metacarcinus magister) production in Willapa Bay, WA

  Oyster reefs provide an array of ecosystem services. Specifically, they provide structurally complex habitat for fish and invertebrate species such as the commercially important Dungeness crab, Metacarcinus ...

  Citation × Citation Citation Abstract Copy Title: Ecosystem services provided by Olympia oyster (Ostrea lurida) habitat and Pacific oyster (Crassostrea gigas) habitat; Dungeness crab (Metacarcinus magister) production in Willapa Bay, WA Author: Ramsay, Jessica Oyster reefs provide an array of ecosystem services. Specifically, they provide structurally complex habitat for fish and invertebrate species such as the commercially important Dungeness crab, Metacarcinus magister. This ecosystem service, once provided by the native oyster Ostrea lurida, is now provided by the commercially cultured oyster Crassostrea gigas in many estuaries on the U.S west coast. An economic investigation was conducted examining the ecosystem services provided by oyster habitat, common economic valuation theories and techniques, and tradeoffs between oyster restoration and aquaculture expansion. A scientific investigation, comprised of three studies, was also conducted to examine Dungeness crab production as an ecosystem service provided by oyster habitat. Because natural ecosystems, such as oyster reefs, provide beneficial goods and services through time, they should be valued as any other economic asset or capital. Until recently many of these beneficial services have not been accounted for within resource management plans, often resulting in the over-exploitation of those resources. Activities such as coastal development, dredging, aquaculture expansion, or even habitat restoration can affect estuarine ecosystems. While valuing the ecosystems themselves might be difficult, valuation of the services they provide can be a useful tool for identifying and protecting key ecosystem services while implementing plans with minimal negative impact. The oysters, O. lurida and C. gigas inhabit different regions of the tidal zone. O. lurida is predominantly found in subtidal and low intertidal regions whereas C. gigas is predominantly found in intertidal regions. The shift in the dominant species has resulted in a subsequent shift of available recruitment habitat for M. magister. We conducted an across-estuary study to examine settlement of M. magister in existing O. lurida, C. gigas, eelgrass, and open mud habitats in Willapa Bay, WA, Netarts Bay, OR, and Coos Bay, OR, to determine tradeoffs in crab production between habitat types. A second study using shell bags as settlement substrate at various tidal elevations was conducted in Yaquina Bay, OR, to obtain density data of M. magister by depth. We used these densities, in combination with pre-existing data from Willapa Bay, to compare the production of Dungeness crab as an ecosystem service historically provided by O. lurida habitat and production currently provided by C. gigas habitat in Willapa Bay, WA. A third study using shell piles was conducted in Yaquina Bay, OR to estimate survival of juvenile M. magister. The results of these three studies generally support prior research indicating that densities of juvenile M. magister are greater in oyster and eelgrass habitats than in open mud, and are generally greater in oyster habitat than in eelgrass. The Yaquina Bay shell bag study indicated greater densities of juvenile M. magister in subtidal regions, while the shell pile study indicated greater densities in higher intertidal regions. Title: Ecosystem services provided by Olympia oyster (Ostrea lurida) habitat and Pacific oyster (Crassostrea gigas) habitat; Dungeness crab (Metacarcinus magister) production in Willapa Bay, WA Author: Ramsay, Jessica Oyster reefs provide an array of ecosystem services. Specifically, they provide structurally complex habitat for fish and invertebrate species such as the commercially important Dungeness crab, Metacarcinus magister. This ecosystem service, once provided by the native oyster Ostrea lurida, is now provided by the commercially cultured oyster Crassostrea gigas in many estuaries on the U.S west coast. An economic investigation was conducted examining the ecosystem services provided by oyster habitat, common economic valuation theories and techniques, and tradeoffs between oyster restoration and aquaculture expansion. A scientific investigation, comprised of three studies, was also conducted to examine Dungeness crab production as an ecosystem service provided by oyster habitat. Because natural ecosystems, such as oyster reefs, provide beneficial goods and services through time, they should be valued as any other economic asset or capital. Until recently many of these beneficial services have not been accounted for within resource management plans, often resulting in the over-exploitation of those resources. Activities such as coastal development, dredging, aquaculture expansion, or even habitat restoration can affect estuarine ecosystems. While valuing the ecosystems themselves might be difficult, valuation of the services they provide can be a useful tool for identifying and protecting key ecosystem services while implementing plans with minimal negative impact. The oysters, O. lurida and C. gigas inhabit different regions of the tidal zone. O. lurida is predominantly found in subtidal and low intertidal regions whereas C. gigas is predominantly found in intertidal regions. The shift in the dominant species has resulted in a subsequent shift of available recruitment habitat for M. magister. We conducted an across-estuary study to examine settlement of M. magister in existing O. lurida, C. gigas, eelgrass, and open mud habitats in Willapa Bay, WA, Netarts Bay, OR, and Coos Bay, OR, to determine tradeoffs in crab production between habitat types. A second study using shell bags as settlement substrate at various tidal elevations was conducted in Yaquina Bay, OR, to obtain density data of M. magister by depth. We used these densities, in combination with pre-existing data from Willapa Bay, to compare the production of Dungeness crab as an ecosystem service historically provided by O. lurida habitat and production currently provided by C. gigas habitat in Willapa Bay, WA. A third study using shell piles was conducted in Yaquina Bay, OR to estimate survival of juvenile M. magister. The results of these three studies generally support prior research indicating that densities of juvenile M. magister are greater in oyster and eelgrass habitats than in open mud, and are generally greater in oyster habitat than in eelgrass. The Yaquina Bay shell bag study indicated greater densities of juvenile M. magister in subtidal regions, while the shell pile study indicated greater densities in higher intertidal regions. Close

• 44. [Article] Success of Seeding Native Compared with Introduced Perennial Vegetation for Revegetating Medusahead-Invaded Sagebrush Rangeland

  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 Society for Range ...

  Citation × Citation Citation Abstract Copy Title: Success of Seeding Native Compared with Introduced Perennial Vegetation for Revegetating Medusahead-Invaded Sagebrush Rangeland Author: Boyd, C. S., Nafus, A. M., Davies, K. W., Madsen, M. D., Johnson, D. D. 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 Society for Range Management and published by Elsevier. It can be found at: http://www.elsevier.com/locate/rama Title: Success of Seeding Native Compared with Introduced Perennial Vegetation for Revegetating Medusahead-Invaded Sagebrush Rangeland Author: Boyd, C. S., Nafus, A. M., Davies, K. W., Madsen, M. D., Johnson, D. D. 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 Society for Range Management and published by Elsevier. It can be found at: http://www.elsevier.com/locate/rama Close

• 45. [Article] The effects of site preparation on native forb establishment in a wet prairie, Willamette Valley, Oregon

  Wetlands and wet prairies are economically and environmentally valuable ecosystems, but many have been degraded or converted to other uses. As human understanding of wetlands' value has increased, restoration ...

  Citation × Citation Citation Abstract Copy Title: The effects of site preparation on native forb establishment in a wet prairie, Willamette Valley, Oregon Author: Norman, Katherine N. Wetlands and wet prairies are economically and environmentally valuable ecosystems, but many have been degraded or converted to other uses. As human understanding of wetlands' value has increased, restoration efforts have grown correspondingly. Restoration attempts use a diversity of methods, which often include seeding with native plant species. This thesis reports on early results from a restoration project that was conducted in the Willamette Valley of western Oregon on a study site that historically supported wet prairie but had been converted to agricultural use. The site was withdrawn from agricultural use 11 – 12 years prior to the work reported here, contoured to reestablish wetland hydrological conditions, and planted with the native perennial, tufted hairgrass (Deschampsia cespitosa), in a preliminary attempt to recreate wet prairie conditions. The subsequent management goal, addressed in the work reported here, was to increase native species richness without increasing exotic plant cover by seeding the site with a mixture of 27 common wetland natives. In each of three blocks at the site, four units were treated either by burning (N = 2 per block) or mowing (N = 2 per block), then seeded with a mixture of 27 common native wetland species. One each of the burned and mowed units from each block was treated with glyphosate herbicide. Thus burning, burning + herbicide, mowing, mowing + herbicide, all with seeding of native species, and an unseeded control each occurred in one unit in each of three blocks at the site. The specific objectives of this study were to determine: 1. If treatments varied in their effects on plant communities, 2. Whether treatments differed in the degree to which they enhanced establishment of seeded species or other native species, 3. If so, which treatment was most effective at increasing cover or richness of native or seeded species, and 4. Consequences of treatments in terms of exotic species cover or richness. Although the low number of replications (N = 3) limited statistical inference, it appeared post-treatment plant communities differed among treatment groups (including controls) (Blocked Multi-Response Permutation Procedure; A-value 0.249 to 0.312; p-value < 0.005). While all four seeding treatments enhanced cover by native species compared to that in controls, burning without herbicide appeared to be particularly effective. Burning and burning + herbicide enhanced cover of seeded species more than did mowing treatments; while all four seeding treatments appeared to increase richness of native species overall, relative to that in unseeded controls, differences were not statistically significant. However, treatments also tended to increase cover and richness of exotic species relative to those in controls. While the increases in exotic species richness post-treatment were generally smaller than the increases in native species richness, changes in cover tended to be similar between the two species groups. Further monitoring of this site will be necessary to determine longer term consequences of these treatments for the plant communities. Title: The effects of site preparation on native forb establishment in a wet prairie, Willamette Valley, Oregon Author: Norman, Katherine N. Wetlands and wet prairies are economically and environmentally valuable ecosystems, but many have been degraded or converted to other uses. As human understanding of wetlands' value has increased, restoration efforts have grown correspondingly. Restoration attempts use a diversity of methods, which often include seeding with native plant species. This thesis reports on early results from a restoration project that was conducted in the Willamette Valley of western Oregon on a study site that historically supported wet prairie but had been converted to agricultural use. The site was withdrawn from agricultural use 11 – 12 years prior to the work reported here, contoured to reestablish wetland hydrological conditions, and planted with the native perennial, tufted hairgrass (Deschampsia cespitosa), in a preliminary attempt to recreate wet prairie conditions. The subsequent management goal, addressed in the work reported here, was to increase native species richness without increasing exotic plant cover by seeding the site with a mixture of 27 common wetland natives. In each of three blocks at the site, four units were treated either by burning (N = 2 per block) or mowing (N = 2 per block), then seeded with a mixture of 27 common native wetland species. One each of the burned and mowed units from each block was treated with glyphosate herbicide. Thus burning, burning + herbicide, mowing, mowing + herbicide, all with seeding of native species, and an unseeded control each occurred in one unit in each of three blocks at the site. The specific objectives of this study were to determine: 1. If treatments varied in their effects on plant communities, 2. Whether treatments differed in the degree to which they enhanced establishment of seeded species or other native species, 3. If so, which treatment was most effective at increasing cover or richness of native or seeded species, and 4. Consequences of treatments in terms of exotic species cover or richness. Although the low number of replications (N = 3) limited statistical inference, it appeared post-treatment plant communities differed among treatment groups (including controls) (Blocked Multi-Response Permutation Procedure; A-value 0.249 to 0.312; p-value < 0.005). While all four seeding treatments enhanced cover by native species compared to that in controls, burning without herbicide appeared to be particularly effective. Burning and burning + herbicide enhanced cover of seeded species more than did mowing treatments; while all four seeding treatments appeared to increase richness of native species overall, relative to that in unseeded controls, differences were not statistically significant. However, treatments also tended to increase cover and richness of exotic species relative to those in controls. While the increases in exotic species richness post-treatment were generally smaller than the increases in native species richness, changes in cover tended to be similar between the two species groups. Further monitoring of this site will be necessary to determine longer term consequences of these treatments for the plant communities. Close

• 46. [Article] Vertebrates, arthropods, and invasive plants : an investigation of the top-down and bottom-up interactions of multiple herbivore guilds in a grassland system

  Humans are increasing the scale and frequency of many natural disturbances, as well as adding novel disturbances to ecosystems. This thesis uses the arthropod community as a metric to examine the multi-trophic ...

  Citation × Citation Citation Abstract Copy Title: Vertebrates, arthropods, and invasive plants : an investigation of the top-down and bottom-up interactions of multiple herbivore guilds in a grassland system Author: Farrell, Kelly Anne Humans are increasing the scale and frequency of many natural disturbances, as well as adding novel disturbances to ecosystems. This thesis uses the arthropod community as a metric to examine the multi-trophic responses to disturbances in California grasslands. Chapter 2 explores how the long-term exclusion of native vertebrate herbivores has impacted arthropod community and trophic structure at Hastings Natural History Reserve. Chapter 3 investigates the impacts of grazing and invasive plants on the arthropod community in a manipulative plant provenance x grazing experiment that had been in place for two years at the Sierra Foothills Research and Extension Center. Few long-term studies have explored the interactions between vertebrate herbivore guilds and the arthropod community. We studied the long-term impact on arthropod community structure and composition of removing vertebrate herbivores from a California oak savannah. We used paired plots to sample arthropods and plant communities inside and outside 11 long-term vertebrate exclosures. We found that arthropods respond to vertebrate access mainly via plant compositional shifts, but that different groups of vertebrates cause changes via different pathways. Large herbivores, including deer, caused a shift from native perennial to exotic annual plants which increased plant nutritional content and supported more herbivore and detritivore arthropods. Burrowing vertebrates such as gophers reduced the predatory arthropod community by reducing vegetation structure, releasing other arthropod groups and resulting in an overall increase in arthropod abundance. These results highlight that alterations to different parts of the vertebrate community can have qualitatively different effects on arthropod community structure. The invasion and spread of non-native plants and the prevalence of livestock grazing are two human-induced disturbances that can have widespread ecosystem impacts. We used a manipulative study to examine how the replacement of native perennial grasses by exotic annual grasses and the introduction of heavy cattle grazing impact arthropod community structure. Arthropod richness, diversity, and abundance did not vary predictably between native perennial and exotic annual grass communities, though arthropods responded to plant community characteristics. In the presence of grazing, arthropod biovolume increased in annual grass treatments, which could trigger a positive-feedback cycle with vector-transmitted plant pathogens to further increase the prevalence of non-native annual grasses. Arthropod community was strongly impacted by cattle grazing, which decreased the biovolume of predatory arthropods, causing a top-down increase in herbivorous arthropod biovolume. Grazing thus impacts plant composition both through the direct removal of biomass and increased plant species evenness, and through arthropod-mediated impacts. Together, these studies show that human alterations of different vertebrate guilds can impact the trophic structure of the arthropod community. Because arthropods mediate a number of ecosystem services, disturbances that alter arthropod assemblages can have far-reaching ecosystem impacts. By exploring the mechanisms by which manipulations of the vertebrate guild alter arthropod community, this thesis demonstrates the importance of horizontal and vertical diversity in multi-trophic interactions. Title: Vertebrates, arthropods, and invasive plants : an investigation of the top-down and bottom-up interactions of multiple herbivore guilds in a grassland system Author: Farrell, Kelly Anne Humans are increasing the scale and frequency of many natural disturbances, as well as adding novel disturbances to ecosystems. This thesis uses the arthropod community as a metric to examine the multi-trophic responses to disturbances in California grasslands. Chapter 2 explores how the long-term exclusion of native vertebrate herbivores has impacted arthropod community and trophic structure at Hastings Natural History Reserve. Chapter 3 investigates the impacts of grazing and invasive plants on the arthropod community in a manipulative plant provenance x grazing experiment that had been in place for two years at the Sierra Foothills Research and Extension Center. Few long-term studies have explored the interactions between vertebrate herbivore guilds and the arthropod community. We studied the long-term impact on arthropod community structure and composition of removing vertebrate herbivores from a California oak savannah. We used paired plots to sample arthropods and plant communities inside and outside 11 long-term vertebrate exclosures. We found that arthropods respond to vertebrate access mainly via plant compositional shifts, but that different groups of vertebrates cause changes via different pathways. Large herbivores, including deer, caused a shift from native perennial to exotic annual plants which increased plant nutritional content and supported more herbivore and detritivore arthropods. Burrowing vertebrates such as gophers reduced the predatory arthropod community by reducing vegetation structure, releasing other arthropod groups and resulting in an overall increase in arthropod abundance. These results highlight that alterations to different parts of the vertebrate community can have qualitatively different effects on arthropod community structure. The invasion and spread of non-native plants and the prevalence of livestock grazing are two human-induced disturbances that can have widespread ecosystem impacts. We used a manipulative study to examine how the replacement of native perennial grasses by exotic annual grasses and the introduction of heavy cattle grazing impact arthropod community structure. Arthropod richness, diversity, and abundance did not vary predictably between native perennial and exotic annual grass communities, though arthropods responded to plant community characteristics. In the presence of grazing, arthropod biovolume increased in annual grass treatments, which could trigger a positive-feedback cycle with vector-transmitted plant pathogens to further increase the prevalence of non-native annual grasses. Arthropod community was strongly impacted by cattle grazing, which decreased the biovolume of predatory arthropods, causing a top-down increase in herbivorous arthropod biovolume. Grazing thus impacts plant composition both through the direct removal of biomass and increased plant species evenness, and through arthropod-mediated impacts. Together, these studies show that human alterations of different vertebrate guilds can impact the trophic structure of the arthropod community. Because arthropods mediate a number of ecosystem services, disturbances that alter arthropod assemblages can have far-reaching ecosystem impacts. By exploring the mechanisms by which manipulations of the vertebrate guild alter arthropod community, this thesis demonstrates the importance of horizontal and vertical diversity in multi-trophic interactions. Close

• 47. [Article] Forecasting functional implications of global changes in riparian plant communities

  This is the publisher’s final pdf. The published article is copyrighted by Ecological Society of America and can be found at: http://esa.org/.

  Citation × Citation Citation Abstract Copy Title: Forecasting functional implications of global changes in riparian plant communities Author: Mineau, Madeleine M., McElarney, Yvonne R., Fischer, Dylan G., Tiegs, Scott D., Canhoto, Cristina, Larranaga, Aitor, Giling, Darren P., Swan, Christopher M., Kominoski, John S., LeRoy, Carri J., Gonzalez, Eduardo, Griffiths, Natalie A., Shirley, Susan M., Follstad Shah, Jennifer J. This is the publisher’s final pdf. The published article is copyrighted by Ecological Society of America and can be found at: http://esa.org/. Title: Forecasting functional implications of global changes in riparian plant communities Author: Mineau, Madeleine M., McElarney, Yvonne R., Fischer, Dylan G., Tiegs, Scott D., Canhoto, Cristina, Larranaga, Aitor, Giling, Darren P., Swan, Christopher M., Kominoski, John S., LeRoy, Carri J., Gonzalez, Eduardo, Griffiths, Natalie A., Shirley, Susan M., Follstad Shah, Jennifer J. This is the publisher’s final pdf. The published article is copyrighted by Ecological Society of America and can be found at: http://esa.org/. Close

• 48. [Article] Comparing vegetation and soils of remnant and restored prairie wetlands in the northern Willamette Valley

  Native prairies of the Willamette Valley are considered among the rarest of Oregon's ecosystems (Clark and Wilson, 2001). As a result of agriculture conversion, urban development and cessation of native ...

  Citation × Citation Citation Abstract Copy Title: Comparing vegetation and soils of remnant and restored prairie wetlands in the northern Willamette Valley Author: Taylor, Sara M. Native prairies of the Willamette Valley are considered among the rarest of Oregon's ecosystems (Clark and Wilson, 2001). As a result of agriculture conversion, urban development and cessation of native burning, Willamette Valley prairies have become highly fragmented and invaded by non-native species, leaving little room for native plant diversity. Even though wetland prairie conservation and restoration has been a priority for many government agencies there is a need for research on what restoration techniques and management are necessary for increasing native species richness and abundance in remnant and restored wet prairie sites. In this research project, two studies were conducted. In the first study, data were collected on species presence and abundance from three 100m² randomized plots within three remnant wet prairies (Green Mountain, Gotter Prairie South, Knez) and three restored wet prairies (Hutchinson, Gotter Prairie North, Lovejoy) to answer the following research question, 'Are there differences between remnant and restored prairie plant communities with respect to the diversity and abundance of native species?' Analysis of variance and multivariate ordination techniques were used to assess the ecological differences between uncultivated, minimally-managed remnant wet prairies and newly-restored, highly managed wet prairies. Data on soils collected from agricultural sites (Westbrook, Zurcher, Gotter Prairie Ag), as well as the remnant and restored wet prairies mentioned above, were also used to compare soil quality and processes with the remnant and restored wetlands. Restored wet prairie had 23% higher native species cover than remnant prairie (p-value=0.089, N=6). Remnant and restored sites did not differ in native species richness (p-value=0.949, N=6). The relatively high per cent cover of native species at restored sites, (significant at the 10% level), suggests that land managers have successfully restored agricultural properties with an abundance of native species. The lack of significant difference in native species richness between remnant and restored sites also suggests that land managers have also been able to restore native plant diversity into former agricultural properties equivalent to some of the best intact remnant prairies within the Northern Willamette Valley in a short period of time (8 years or less). However, a non-metric scaling (NMS) ordination of the species matrix separated the remnant sites from the restored sites, suggesting that community composition distinguishes restored sites from remnants. The NMS results, which include environmental data in the analysis, also suggest that there is a positive correlation of percent soil moisture and percent soil organic matter associated with the remnant prairies and a positive correlation of management practices such as yearly chemical use, mowing, and clean crops, associated with the restored prairies. The location of Gotter Prairie North restoration within the ordination, between the remnant and restored sites, suggests an intermediate plant composition and soil quality. This could be attributed to intensive weed suppression and soil organic matter build up over time (8 years) in comparison to younger restored sites (3 and 4 years). Indicator species analysis identified many species with high indicator values (IVs) in the remnant prairies; Holcus lanatus, Deschampsia cespitosa, Carex densa and Phalaris arundinacea being the highest. The use of fire as a management tool produced only one species with a high IV (Camassia quamash). In the second study, three seeding treatments (Grass first, Grass and Forb together, Forb first) were compared within a 4 hectare experimental wet prairie unit to answer the research question „Which of the three seeding treatments used leads to the highest native species abundance and species richness?‟ Results from an analysis of variance indicated significant differences between treatments in native species richness for 2009 and 2010 (p-values=0.002 & 0.004 respectively) at the 5% level and native species abundance in 2010 only (p-value=0.099) at the 10% level. The Grass and Forb and Forb first treatments were highest in native species richness for 2009 and 2010, whereas the Grass and Forb and Grass first treatments were highest in native species abundance in 2010. A NMS ordination suggests that Juncus tenuis is one of the dominant species, in all seeding treatments, after one year of growth. Title: Comparing vegetation and soils of remnant and restored prairie wetlands in the northern Willamette Valley Author: Taylor, Sara M. Native prairies of the Willamette Valley are considered among the rarest of Oregon's ecosystems (Clark and Wilson, 2001). As a result of agriculture conversion, urban development and cessation of native burning, Willamette Valley prairies have become highly fragmented and invaded by non-native species, leaving little room for native plant diversity. Even though wetland prairie conservation and restoration has been a priority for many government agencies there is a need for research on what restoration techniques and management are necessary for increasing native species richness and abundance in remnant and restored wet prairie sites. In this research project, two studies were conducted. In the first study, data were collected on species presence and abundance from three 100m² randomized plots within three remnant wet prairies (Green Mountain, Gotter Prairie South, Knez) and three restored wet prairies (Hutchinson, Gotter Prairie North, Lovejoy) to answer the following research question, 'Are there differences between remnant and restored prairie plant communities with respect to the diversity and abundance of native species?' Analysis of variance and multivariate ordination techniques were used to assess the ecological differences between uncultivated, minimally-managed remnant wet prairies and newly-restored, highly managed wet prairies. Data on soils collected from agricultural sites (Westbrook, Zurcher, Gotter Prairie Ag), as well as the remnant and restored wet prairies mentioned above, were also used to compare soil quality and processes with the remnant and restored wetlands. Restored wet prairie had 23% higher native species cover than remnant prairie (p-value=0.089, N=6). Remnant and restored sites did not differ in native species richness (p-value=0.949, N=6). The relatively high per cent cover of native species at restored sites, (significant at the 10% level), suggests that land managers have successfully restored agricultural properties with an abundance of native species. The lack of significant difference in native species richness between remnant and restored sites also suggests that land managers have also been able to restore native plant diversity into former agricultural properties equivalent to some of the best intact remnant prairies within the Northern Willamette Valley in a short period of time (8 years or less). However, a non-metric scaling (NMS) ordination of the species matrix separated the remnant sites from the restored sites, suggesting that community composition distinguishes restored sites from remnants. The NMS results, which include environmental data in the analysis, also suggest that there is a positive correlation of percent soil moisture and percent soil organic matter associated with the remnant prairies and a positive correlation of management practices such as yearly chemical use, mowing, and clean crops, associated with the restored prairies. The location of Gotter Prairie North restoration within the ordination, between the remnant and restored sites, suggests an intermediate plant composition and soil quality. This could be attributed to intensive weed suppression and soil organic matter build up over time (8 years) in comparison to younger restored sites (3 and 4 years). Indicator species analysis identified many species with high indicator values (IVs) in the remnant prairies; Holcus lanatus, Deschampsia cespitosa, Carex densa and Phalaris arundinacea being the highest. The use of fire as a management tool produced only one species with a high IV (Camassia quamash). In the second study, three seeding treatments (Grass first, Grass and Forb together, Forb first) were compared within a 4 hectare experimental wet prairie unit to answer the research question „Which of the three seeding treatments used leads to the highest native species abundance and species richness?‟ Results from an analysis of variance indicated significant differences between treatments in native species richness for 2009 and 2010 (p-values=0.002 & 0.004 respectively) at the 5% level and native species abundance in 2010 only (p-value=0.099) at the 10% level. The Grass and Forb and Forb first treatments were highest in native species richness for 2009 and 2010, whereas the Grass and Forb and Grass first treatments were highest in native species abundance in 2010. A NMS ordination suggests that Juncus tenuis is one of the dominant species, in all seeding treatments, after one year of growth. Close

• 49. [Article] Mercury bioaccumulation in remote subalpine lakes : assessing the influence of invasive trout on salamanders

  Mercury (Hg) contamination is a global conservation threat to freshwater ecosystems, detected in even the protected lakes of Olympic National Park (Washington, USA). Although considered some of the most ...

  Citation × Citation Citation Abstract Copy Title: Mercury bioaccumulation in remote subalpine lakes : assessing the influence of invasive trout on salamanders Author: Pfleeger, Adam Mercury (Hg) contamination is a global conservation threat to freshwater ecosystems, detected in even the protected lakes of Olympic National Park (Washington, USA). Although considered some of the most remote and pristine US ecosystems, these lakes are currently subject to multiple environmental stressors, including climate change and fish introductions; adding contaminants, such as Hg, could exacerbate the effects of these stressors on native species. Amphibians are undergoing large worldwide declines, which include declines in protected areas, such as our National Parks. Our goal is to better understand the effect of historically stocked fish in Olympic National Park on native amphibian Hg bioaccumulation. To minimize the need for lethal sampling of this already threatened group, we first examine how Hg concentrations in non-lethally sampled amphibian tissues correlated with whole-body Hg concentrations, depending on species and the different type of non-lethal tissue sample used. Second, we aimed to understand how a food web altered by fish impacted Hg bioaccumulation in native species. We measured Hg and stable isotopes of carbon and nitrogen in organisms across trophic levels from 18 subalpine lakes. We detected small shifts in salamander food web indices and minor changes to salamander Hg concentration associated with the presence of fish. Importantly, we found increased mercury trophic magnification slopes in lakes with fish compared to fishless lakes. This research provides evidence that historic fish introductions can elevate mercury exposure in pristine ecosystems compared to natural fishless lakes. Title: Mercury bioaccumulation in remote subalpine lakes : assessing the influence of invasive trout on salamanders Author: Pfleeger, Adam Mercury (Hg) contamination is a global conservation threat to freshwater ecosystems, detected in even the protected lakes of Olympic National Park (Washington, USA). Although considered some of the most remote and pristine US ecosystems, these lakes are currently subject to multiple environmental stressors, including climate change and fish introductions; adding contaminants, such as Hg, could exacerbate the effects of these stressors on native species. Amphibians are undergoing large worldwide declines, which include declines in protected areas, such as our National Parks. Our goal is to better understand the effect of historically stocked fish in Olympic National Park on native amphibian Hg bioaccumulation. To minimize the need for lethal sampling of this already threatened group, we first examine how Hg concentrations in non-lethally sampled amphibian tissues correlated with whole-body Hg concentrations, depending on species and the different type of non-lethal tissue sample used. Second, we aimed to understand how a food web altered by fish impacted Hg bioaccumulation in native species. We measured Hg and stable isotopes of carbon and nitrogen in organisms across trophic levels from 18 subalpine lakes. We detected small shifts in salamander food web indices and minor changes to salamander Hg concentration associated with the presence of fish. Importantly, we found increased mercury trophic magnification slopes in lakes with fish compared to fishless lakes. This research provides evidence that historic fish introductions can elevate mercury exposure in pristine ecosystems compared to natural fishless lakes. Close

• 50. [Article] Progress report II: Restoring prairies: A synthesis of studies on vegetation and invasive species in support of effective management (Year two)

  Willamette Valley wetland and upland prairies are some of the most endangered ecosystems in the United States, and provide habitat for many federally listed species. Because these are dynamic systems, ...

  Citation × Citation Citation Abstract Copy Title: Progress report II: Restoring prairies: A synthesis of studies on vegetation and invasive species in support of effective management (Year two) Author: Wilson, Mark V., Clark, Deborah Louise, 1950- Willamette Valley wetland and upland prairies are some of the most endangered ecosystems in the United States, and provide habitat for many federally listed species. Because these are dynamic systems, subject to ecological succession and invasion by aggressive non-native species, prairies require active management to maintain management goals. This is true of all Willamette Valley prairies, whether intact, degraded, or reestablished. Yet restoration and conservation efforts often lack experimental validation. Our overall objective for this project is to synthesize the scientific information now available relevant to the prairie restoration efforts of the West Eugene Wetlands project and, where there is sufficient support, develop concrete and defensible management recommendations Successful ecosystem restoration requires establishing and maintaining native plants. In turn, plant establishment hinges on having suitable environmental conditions, using species with adequate germination rates, and reducing competitive pressure from nonnative plants. In year one of this project, we synthesized the wealth of data in the West Eugene Wetlands establishment data set on plant abundance after sowing native species during wetland restoration (Wilson 2004). In year two, we will build and expand on these results in several important ways: • We are generalizing these results through the investigation of plant traits that consistently correspond to the patterns of establishment and vigor. • We are systematically compiling the results from year one and year two of this project into a public database. We are adding to this database findings from similar ecosystems, both in the Willamette Valley and elsewhere. • We are considering further the role of microsite variability on seedling establishment patterns. • We are synthesizing these results into scientific conclusions. • We are integrating these results, where there is sufficient support, into concrete and defensible management recommendations Our goal is to develop an ability to predict key aspects of prairie restoration performance, such as establishment rates, based on knowing species traits, site conditions, and maintenance. These predictions can then be converted into management recommendations, such as which species to sow and which site preparation and maintenance regimes should be followed to maximize native plant abundance and minimize non-native plant abundance at a given site. The two components of our project –plant traits and the database– are crucial to this goal. • Without the generalization that traits allow, understanding of wetland restoration increases slowly and expensively, one case study at a time. • The organization of the database will increase the power and efficiency of revealing the relationships between plant traits and plant performance. Perhaps even more important is the role of the database as a first step in developing a Web-based expert system for managers wishing to plan wetland restorations Title: Progress report II: Restoring prairies: A synthesis of studies on vegetation and invasive species in support of effective management (Year two) Author: Wilson, Mark V., Clark, Deborah Louise, 1950- Willamette Valley wetland and upland prairies are some of the most endangered ecosystems in the United States, and provide habitat for many federally listed species. Because these are dynamic systems, subject to ecological succession and invasion by aggressive non-native species, prairies require active management to maintain management goals. This is true of all Willamette Valley prairies, whether intact, degraded, or reestablished. Yet restoration and conservation efforts often lack experimental validation. Our overall objective for this project is to synthesize the scientific information now available relevant to the prairie restoration efforts of the West Eugene Wetlands project and, where there is sufficient support, develop concrete and defensible management recommendations Successful ecosystem restoration requires establishing and maintaining native plants. In turn, plant establishment hinges on having suitable environmental conditions, using species with adequate germination rates, and reducing competitive pressure from nonnative plants. In year one of this project, we synthesized the wealth of data in the West Eugene Wetlands establishment data set on plant abundance after sowing native species during wetland restoration (Wilson 2004). In year two, we will build and expand on these results in several important ways: • We are generalizing these results through the investigation of plant traits that consistently correspond to the patterns of establishment and vigor. • We are systematically compiling the results from year one and year two of this project into a public database. We are adding to this database findings from similar ecosystems, both in the Willamette Valley and elsewhere. • We are considering further the role of microsite variability on seedling establishment patterns. • We are synthesizing these results into scientific conclusions. • We are integrating these results, where there is sufficient support, into concrete and defensible management recommendations Our goal is to develop an ability to predict key aspects of prairie restoration performance, such as establishment rates, based on knowing species traits, site conditions, and maintenance. These predictions can then be converted into management recommendations, such as which species to sow and which site preparation and maintenance regimes should be followed to maximize native plant abundance and minimize non-native plant abundance at a given site. The two components of our project –plant traits and the database– are crucial to this goal. • Without the generalization that traits allow, understanding of wetland restoration increases slowly and expensively, one case study at a time. • The organization of the database will increase the power and efficiency of revealing the relationships between plant traits and plant performance. Perhaps even more important is the role of the database as a first step in developing a Web-based expert system for managers wishing to plan wetland restorations Close