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• 11. [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

• 12. [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

• 13. [Article] 2009 Foskett Spring Speckled Dace Investigations Progress Report 2009

  Abstract -- Speckled dace (Rhinichthys osculus) are geographically widespread throughout the western United States and occur in many isolated subbasins and interior drainages in south-central Oregon. The ...

  Citation × Citation Citation Abstract Copy Title: 2009 Foskett Spring Speckled Dace Investigations Progress Report 2009 Abstract -- Speckled dace (Rhinichthys osculus) are geographically widespread throughout the western United States and occur in many isolated subbasins and interior drainages in south-central Oregon. The Foskett Spring speckled dace (R. osculus ssp.) is represented by a single population that inhabits Foskett Spring (Figure 1) on the west side of Coleman Lake (Warner Lakes subbasin) in Lake County, Oregon. Foskett speckled dace was listed as threatened under the federal Endangered Species Act in 1985 (U.S. Fish and Wildlife Service 1985). The Foskett speckled dace became isolated in Foskett Spring at the end of the Pluvial period (~9,000-10,000 years ago). Foskett Spring is a natural spring that rises from a springhead pool, flows through a narrow spring brook into a series of shallow marshes, and then disappears into the soil of the normally dry Coleman Lake (Figure 1). A second population in Dace Spring, located approximately 0.8 kilometer south of Foskett Spring, was established from an introduction of 100 fish from Foskett Spring in 1979-1980 (Williams et al. 1990); however recent surveys have failed to document their continued existence at this location. In 1987, the U.S. Bureau of Land Management (BLM) acquired, through exchange, the 65 hectare parcel of land containing Foskett and Dace Springs. Both sites were fenced to exclude livestock. The Recovery Plan for the threatened and rare native fishes of the Warner Basin and Alkali Subbasin states that Foskett speckled dace will probably not be delisted in the near future because of its extremely isolated range and potential for degradation of its habitat from localized events (USFWS 1997). The primary recovery objective for this species is long-term persistence through preservation of its native ecosystem. The plan further states that the conservation and long term sustainability of this species will be met when: 1) long-term protection of its habitat, including spring source aquifers, springpools and outflow channels, and surrounding lands is assured; 2) long-term habitat management guidelines are developed and implemented to ensure the continued persistence of important habitat features and guidelines include monitoring of current habitat and investigation for and evaluation of new spring habitats; and 3) research into life-history, genetics, population trends, habitat use and preference, and other important parameters is conducted to assist in further developing or refining criteria 1) and 2), above. Actions needed to meet these criteria include protecting the fish population and its habitat, conserving genetic diversity of the fish population, ensuring adequate water supplies are available, monitoring of the dace population and habitat conditions, and evaluating long-term effects of climatic trends on recovery of this fish population. The purpose of this investigation was to determine the status of the federally listed Foskett Spring speckled dace and its habitat. This report updates a monitoring program initiated in 2005 by ODFW (Scheerer and Jacobs 2005) by providing results of monitoring conducted in 2009. Specifically, this monitoring program calls for biannual estimates of population abundance, assessments of distribution and demographic parameters and assessments of physical habitat conditions. Title: 2009 Foskett Spring Speckled Dace Investigations Progress Report 2009 Abstract -- Speckled dace (Rhinichthys osculus) are geographically widespread throughout the western United States and occur in many isolated subbasins and interior drainages in south-central Oregon. The Foskett Spring speckled dace (R. osculus ssp.) is represented by a single population that inhabits Foskett Spring (Figure 1) on the west side of Coleman Lake (Warner Lakes subbasin) in Lake County, Oregon. Foskett speckled dace was listed as threatened under the federal Endangered Species Act in 1985 (U.S. Fish and Wildlife Service 1985). The Foskett speckled dace became isolated in Foskett Spring at the end of the Pluvial period (~9,000-10,000 years ago). Foskett Spring is a natural spring that rises from a springhead pool, flows through a narrow spring brook into a series of shallow marshes, and then disappears into the soil of the normally dry Coleman Lake (Figure 1). A second population in Dace Spring, located approximately 0.8 kilometer south of Foskett Spring, was established from an introduction of 100 fish from Foskett Spring in 1979-1980 (Williams et al. 1990); however recent surveys have failed to document their continued existence at this location. In 1987, the U.S. Bureau of Land Management (BLM) acquired, through exchange, the 65 hectare parcel of land containing Foskett and Dace Springs. Both sites were fenced to exclude livestock. The Recovery Plan for the threatened and rare native fishes of the Warner Basin and Alkali Subbasin states that Foskett speckled dace will probably not be delisted in the near future because of its extremely isolated range and potential for degradation of its habitat from localized events (USFWS 1997). The primary recovery objective for this species is long-term persistence through preservation of its native ecosystem. The plan further states that the conservation and long term sustainability of this species will be met when: 1) long-term protection of its habitat, including spring source aquifers, springpools and outflow channels, and surrounding lands is assured; 2) long-term habitat management guidelines are developed and implemented to ensure the continued persistence of important habitat features and guidelines include monitoring of current habitat and investigation for and evaluation of new spring habitats; and 3) research into life-history, genetics, population trends, habitat use and preference, and other important parameters is conducted to assist in further developing or refining criteria 1) and 2), above. Actions needed to meet these criteria include protecting the fish population and its habitat, conserving genetic diversity of the fish population, ensuring adequate water supplies are available, monitoring of the dace population and habitat conditions, and evaluating long-term effects of climatic trends on recovery of this fish population. The purpose of this investigation was to determine the status of the federally listed Foskett Spring speckled dace and its habitat. This report updates a monitoring program initiated in 2005 by ODFW (Scheerer and Jacobs 2005) by providing results of monitoring conducted in 2009. Specifically, this monitoring program calls for biannual estimates of population abundance, assessments of distribution and demographic parameters and assessments of physical habitat conditions. Close

• 14. [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

• 15. [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

• 16. [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

• 17. [Article] Oregon Natural Areas Plan

  The rich diversity of ecosystems and native plants and animals is one of Oregon's most distinctive and valued qualities. Our state contains rain forests, dry forests, oak woodlands, alpine meadows, prairies, ...

  Citation × Citation Citation Abstract Copy Title: Oregon Natural Areas Plan Author: Oregon Natural Heritage Advisory Council Year: 2010 The rich diversity of ecosystems and native plants and animals is one of Oregon's most distinctive and valued qualities. Our state contains rain forests, dry forests, oak woodlands, alpine meadows, prairies, deserts, marshes, estuaries, dunes, rocky headlands, lakes and streams. There are a number of reasons it is so diverse. First are the extremes of climate, with rainfall ranging from over 200 inches a year along Oregon’s north coast, to less than 7 inches a year in the Alvord Desert, and temperatures from the very mild banana belt along the coast near the California border to the extremes of the high alpine areas of the Wallowa Mountains. Secondly, Oregon is diverse geographically and geologically, having ancient serpentine landscapes in the Siskiyou Mountains and recent volcanics in the Cascades and the deepest gorge in North America at Hells Canyon. Lastly, Oregon is a floristic crossroads, with arctic boreal species finding their southern limit, Rocky Mountain species common in northeastern Oregon, Great Basin species in southeastern Oregon, and California coastal and Sierra species in the southwest, all mixing with native northwestern taxa to create a wide array of habitats. Title: Oregon Natural Areas Plan Author: Oregon Natural Heritage Advisory Council Year: 2010 The rich diversity of ecosystems and native plants and animals is one of Oregon's most distinctive and valued qualities. Our state contains rain forests, dry forests, oak woodlands, alpine meadows, prairies, deserts, marshes, estuaries, dunes, rocky headlands, lakes and streams. There are a number of reasons it is so diverse. First are the extremes of climate, with rainfall ranging from over 200 inches a year along Oregon’s north coast, to less than 7 inches a year in the Alvord Desert, and temperatures from the very mild banana belt along the coast near the California border to the extremes of the high alpine areas of the Wallowa Mountains. Secondly, Oregon is diverse geographically and geologically, having ancient serpentine landscapes in the Siskiyou Mountains and recent volcanics in the Cascades and the deepest gorge in North America at Hells Canyon. Lastly, Oregon is a floristic crossroads, with arctic boreal species finding their southern limit, Rocky Mountain species common in northeastern Oregon, Great Basin species in southeastern Oregon, and California coastal and Sierra species in the southwest, all mixing with native northwestern taxa to create a wide array of habitats. Close

• 18. [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

• 19. [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

• 20. [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