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• 1. [Article] Food abundance and energetic carrying capacity for wintering waterfowl in the Great Salt Lake wetlands

  Great Salt Lake (GSL), Utah, is surrounded by 191,884 hectares of wetlands. These wetlands provide critical habitat for hundreds of thousands of breeding, migrating and wintering waterfowl each year. ...

  Citation × Citation Citation Abstract Copy Title: Food abundance and energetic carrying capacity for wintering waterfowl in the Great Salt Lake wetlands Author: Johnson, Amber Marie Great Salt Lake (GSL), Utah, is surrounded by 191,884 hectares of wetlands. These wetlands provide critical habitat for hundreds of thousands of breeding, migrating and wintering waterfowl each year. As the human population around GSL increases, government officials have proposed to divert more water from the Jordan, Ogden, and Bear Rivers to meet municipal demands. Freshwater diversions from the rivers that supply the wetlands will likely decrease the amount of wetland habitat available to waterfowl. To justify current and future water allocation for wetlands around the GSL, managers must quantify the value of these habitats to migratory wetland birds, and one measure of habitat quality is food abundance. However, food abundance in the GSL wetlands is unknown. In this study, I quantified food abundance in managed and unmanaged wetland areas along the east side of the GSL. Managed wetlands included state, federal, and private lands contained within levees and actively managed as waterfowl habitat. I defined unmanaged wetlands as those shallow water areas outside levees impacted by freshwater flows from the Jordan, Bear, and Ogden Rivers and from managed wetlands. Unmanaged wetlands are under no specific management regime and are under the greatest threat by proposed water diversions because they are currently not protected under Utah water laws. I used multi-stage and simple random sampling to quantify food abundance in managed and unmanaged wetland. Sampling in managed wetlands occurred during September 2005-2006 (n = 12) and unmanaged wetlands during 2006 (n = 3) before the majority of waterfowl arrive on fall migration. I estimated the biomass of seeds, tubers, invertebrates, and submerged aquatic vegetation (SAV). Mean tuber and invertebrate biomass was similar between managed and unmanaged wetlands in 2006 (ps > 0.09); however, leafy biomass was 37% higher in unmanaged wetlands (t = 2.47, p = 0.015) and seed biomass was 65% higher in managed wetlands (t = 5.06, p <0.001). I then used biomass estimates to calculate energetic carrying capacity of both managed and unmanaged wetland habitats and determine the effects of possible water diversions from unmanaged wetlands on migratory waterfowl. I used information on daily bird energy needs, biomass estimates, and true metabolizable energy of each food type to estimate duck carrying capacity in habitats dominated by submerged aquatic vegetation. I separated ducks into three guilds based on food habits and feeding methods (dabblers, divers and grazers). The unit of comparison for energetic carrying capacity was Duck Use Day (DUD), defined as the amount of energy needed to support one duck for one day. Carrying capacity was higher in managed vs. unmanaged habitats for all three duck foraging guilds. If unmanaged wetlands decline by 80%, I estimated that duck carrying capacity would decrease 34% for grazers, 20% for divers, and 14% for dabblers. Results from this research provide a quantitative value to both managed and unmanaged wetlands surrounding the GSL to wintering waterfowl and provide guidance for the future conservation, restoration and maintenance of hundreds of thousands of hectares of critical wetland habitat. Title: Food abundance and energetic carrying capacity for wintering waterfowl in the Great Salt Lake wetlands Author: Johnson, Amber Marie Great Salt Lake (GSL), Utah, is surrounded by 191,884 hectares of wetlands. These wetlands provide critical habitat for hundreds of thousands of breeding, migrating and wintering waterfowl each year. As the human population around GSL increases, government officials have proposed to divert more water from the Jordan, Ogden, and Bear Rivers to meet municipal demands. Freshwater diversions from the rivers that supply the wetlands will likely decrease the amount of wetland habitat available to waterfowl. To justify current and future water allocation for wetlands around the GSL, managers must quantify the value of these habitats to migratory wetland birds, and one measure of habitat quality is food abundance. However, food abundance in the GSL wetlands is unknown. In this study, I quantified food abundance in managed and unmanaged wetland areas along the east side of the GSL. Managed wetlands included state, federal, and private lands contained within levees and actively managed as waterfowl habitat. I defined unmanaged wetlands as those shallow water areas outside levees impacted by freshwater flows from the Jordan, Bear, and Ogden Rivers and from managed wetlands. Unmanaged wetlands are under no specific management regime and are under the greatest threat by proposed water diversions because they are currently not protected under Utah water laws. I used multi-stage and simple random sampling to quantify food abundance in managed and unmanaged wetland. Sampling in managed wetlands occurred during September 2005-2006 (n = 12) and unmanaged wetlands during 2006 (n = 3) before the majority of waterfowl arrive on fall migration. I estimated the biomass of seeds, tubers, invertebrates, and submerged aquatic vegetation (SAV). Mean tuber and invertebrate biomass was similar between managed and unmanaged wetlands in 2006 (ps > 0.09); however, leafy biomass was 37% higher in unmanaged wetlands (t = 2.47, p = 0.015) and seed biomass was 65% higher in managed wetlands (t = 5.06, p <0.001). I then used biomass estimates to calculate energetic carrying capacity of both managed and unmanaged wetland habitats and determine the effects of possible water diversions from unmanaged wetlands on migratory waterfowl. I used information on daily bird energy needs, biomass estimates, and true metabolizable energy of each food type to estimate duck carrying capacity in habitats dominated by submerged aquatic vegetation. I separated ducks into three guilds based on food habits and feeding methods (dabblers, divers and grazers). The unit of comparison for energetic carrying capacity was Duck Use Day (DUD), defined as the amount of energy needed to support one duck for one day. Carrying capacity was higher in managed vs. unmanaged habitats for all three duck foraging guilds. If unmanaged wetlands decline by 80%, I estimated that duck carrying capacity would decrease 34% for grazers, 20% for divers, and 14% for dabblers. Results from this research provide a quantitative value to both managed and unmanaged wetlands surrounding the GSL to wintering waterfowl and provide guidance for the future conservation, restoration and maintenance of hundreds of thousands of hectares of critical wetland habitat. Close

• 2. [Article] Determination of Trade-offs between Wetland Ecosystem Services in an Agricultural Landscape

  Wetland restoration mitigates effects of agricultural development on water quality, flooding, and habitat loss. Multi-objective optimization for wetland locations and sizes has not included objective functions ...

  Citation × Citation Citation Abstract Copy Title: Determination of Trade-offs between Wetland Ecosystem Services in an Agricultural Landscape Author: Garrison, Stacey L. Wetland restoration mitigates effects of agricultural development on water quality, flooding, and habitat loss. Multi-objective optimization for wetland locations and sizes has not included objective functions for water quality, hydrology, and habitat in unison, limiting analysis of trade-offs among these ecosystem services. This study establishes two methods to improve the accuracy of simulating wetland restoration with an optimization-simulation framework for analysis of trade-offs: identification of wetland type and constraining wetland and drainage area configurations to potential field-scale wetlands in the study area. Determination of a wetland habitat type used characteristics of the Hydrogeomorphic Method, and this type was utilized in a land-use/land-cover simulation linked to a species-habitat model. Multi-objective optimization identified optimal wetlands and drainage areas. These wetlands demonstrated redundancy among treatment ecosystem services. Modifying wetlands and drainage areas from the optimally-identified values caused shifts to the trade-off relationships. The habitat objective function conflicted with the treatment objective functions, but at low levels of confidence, demonstrating the necessity to incorporate all the objective function types together into a multi-objective optimization. The methods to increase accurate representation from this study can be incorporated into future studies to improve understanding of wetland ecosystem service processes for land-use planning. Title: Determination of Trade-offs between Wetland Ecosystem Services in an Agricultural Landscape Author: Garrison, Stacey L. Wetland restoration mitigates effects of agricultural development on water quality, flooding, and habitat loss. Multi-objective optimization for wetland locations and sizes has not included objective functions for water quality, hydrology, and habitat in unison, limiting analysis of trade-offs among these ecosystem services. This study establishes two methods to improve the accuracy of simulating wetland restoration with an optimization-simulation framework for analysis of trade-offs: identification of wetland type and constraining wetland and drainage area configurations to potential field-scale wetlands in the study area. Determination of a wetland habitat type used characteristics of the Hydrogeomorphic Method, and this type was utilized in a land-use/land-cover simulation linked to a species-habitat model. Multi-objective optimization identified optimal wetlands and drainage areas. These wetlands demonstrated redundancy among treatment ecosystem services. Modifying wetlands and drainage areas from the optimally-identified values caused shifts to the trade-off relationships. The habitat objective function conflicted with the treatment objective functions, but at low levels of confidence, demonstrating the necessity to incorporate all the objective function types together into a multi-objective optimization. The methods to increase accurate representation from this study can be incorporated into future studies to improve understanding of wetland ecosystem service processes for land-use planning. Close

• 3. [Article] Juvenile Salmonid Use of Freshwater Emergent Wetlands in the Floodplain and Its Implications for Conservation Management

  A recent trend of enhancing freshwater emergent wetlands for waterfowl and other wildlife has raised concern about the effects of such measures on juvenile salmonids. We undertook this study to quantify ...

  Citation × Citation Citation Abstract Copy Title: Juvenile Salmonid Use of Freshwater Emergent Wetlands in the Floodplain and Its Implications for Conservation Management Author: Gresswell, Robert E., Fleming, Ian A., Henning, Julie A. A recent trend of enhancing freshwater emergent wetlands for waterfowl and other wildlife has raised concern about the effects of such measures on juvenile salmonids. We undertook this study to quantify the degree and extent of juvenile Pacific salmon Oncorhynchus spp. utilization of enhanced and unenhanced emergent wetlands within the floodplain of the lower Chehalis River, Washington, and to determine the fate of the salmon using them. Enhanced emergent wetlands contained water control structures that provided an outlet for fish emigration and a longer hydroperiod for rearing than unenhanced wetlands. Age-0 and age-1 coho salmon O. kisutch were the most common salmonid at all sites, enhanced wetlands having significantly higher age-1 abundance than unenhanced wetlands that were a similar distance from the main-stem river. Yearling coho salmon benefited from rearing in two enhanced wetland habitats, where their specific growth rate and minimum estimates of survival (1.43%/d by weight and 30%; 1.37%/d and 57%) were comparable to those in other side-channel rearing studies. Dissolved oxygen concentrations decreased in emergent wetlands throughout the season and approached the limits lethal to juvenile salmon by May or June each year. Emigration patterns suggested that age-0 and age-1 coho salmon emigrated as habitat conditions declined. This observation was further supported by the results of an experimental release of coho salmon. Survival of fish utilizing emergent wetlands was dependent on movement to the river before water quality decreased or stranding occurred from wetland desiccation. Thus, our results suggest that enhancing freshwater wetlands via water control structures can benefit juvenile salmonids, at least in the short term, by providing conditions for greater growth, survival, and emigration. Title: Juvenile Salmonid Use of Freshwater Emergent Wetlands in the Floodplain and Its Implications for Conservation Management Author: Gresswell, Robert E., Fleming, Ian A., Henning, Julie A. A recent trend of enhancing freshwater emergent wetlands for waterfowl and other wildlife has raised concern about the effects of such measures on juvenile salmonids. We undertook this study to quantify the degree and extent of juvenile Pacific salmon Oncorhynchus spp. utilization of enhanced and unenhanced emergent wetlands within the floodplain of the lower Chehalis River, Washington, and to determine the fate of the salmon using them. Enhanced emergent wetlands contained water control structures that provided an outlet for fish emigration and a longer hydroperiod for rearing than unenhanced wetlands. Age-0 and age-1 coho salmon O. kisutch were the most common salmonid at all sites, enhanced wetlands having significantly higher age-1 abundance than unenhanced wetlands that were a similar distance from the main-stem river. Yearling coho salmon benefited from rearing in two enhanced wetland habitats, where their specific growth rate and minimum estimates of survival (1.43%/d by weight and 30%; 1.37%/d and 57%) were comparable to those in other side-channel rearing studies. Dissolved oxygen concentrations decreased in emergent wetlands throughout the season and approached the limits lethal to juvenile salmon by May or June each year. Emigration patterns suggested that age-0 and age-1 coho salmon emigrated as habitat conditions declined. This observation was further supported by the results of an experimental release of coho salmon. Survival of fish utilizing emergent wetlands was dependent on movement to the river before water quality decreased or stranding occurred from wetland desiccation. Thus, our results suggest that enhancing freshwater wetlands via water control structures can benefit juvenile salmonids, at least in the short term, by providing conditions for greater growth, survival, and emigration. Close

• 4. [Article] Patterns in responses of an amphibian assemblage to wetland restoration

  Wetland restoration success in attaining wildlife conservation goals can be confounded by the presence of multiple biological invaders. Wetland management activities typically target invasive plants, ...

  Citation × Citation Citation Abstract Copy Title: Patterns in responses of an amphibian assemblage to wetland restoration Author: Rowe, Jennifer C. Wetland restoration success in attaining wildlife conservation goals can be confounded by the presence of multiple biological invaders. Wetland management activities typically target invasive plants, but bottom-up responses of higher trophic levels in novel communities are difficult to predict. We surveyed plant and amphibian assemblages at 26 sites enrolled in the Wetlands Reserve Program (WRP) in the Willamette Valley, Oregon to determine the relative importance of plant management, non-native species presence, and surrounding landscape for amphibians across multiple life history stages. Explanatory variables negatively associated with native anuran counts included percent invasive plant cover, invasive bullfrog counts, non-native fish presence, and area of urban land cover. In addition, native anurans were positively associated with WRP site age, suggesting that the benefits of restored wetlands may increase over time. Although invasive plant management provided indirect benefits to native amphibians, the most effective way to enhance native amphibian populations may be through eliminating the strong top-down forces exerted by non-native vertebrates. We also explored the impact of restoration activities on predator/prey dynamics by analyzing bullfrog diet contents. We sampled vegetation and analyzed bullfrog diet contents from 10 WRP wetlands categorized by management intensity and hydrology to determine whether prey consumption patterns (abundance, richness, and % large prey), diet breadth, and dietary community (based on taxonomic and prey size composition) differed among wetlands categorized by management regime and hydroperiod. We found disparities in the diet breadth with respect to wetland categories, with bullfrogs consuming a disproportionate abundance of few prey orders at actively managed sites. Diet breadth could have been influenced by frequent applications of restoration treatments, as invertebrate species richness and abundance is often negatively linked to habitat disturbance. Dietary taxonomic composition also differed between wetland groups, but prey size composition did not. Instead, prey size was strongly influenced by site-level vegetation covariates; large-bodied prey consumption was positively associated with plant species richness. However, diet dry mass was highest in wetlands with high invasive plant cover, suggesting that other factors, such as foraging activity rates, should be considered to fully understand how bullfrogs meet energy demands in managed wetlands. Variation in native and invasive amphibian responses to wetland restoration efforts may provide important information on how habitat structure and composition influence trophic dynamics. Given that the outcomes of plant control on wildlife may not follow planned trajectories in invasive-dominated systems, this research addresses the need for a community approach to assessments of restoration success. Title: Patterns in responses of an amphibian assemblage to wetland restoration Author: Rowe, Jennifer C. Wetland restoration success in attaining wildlife conservation goals can be confounded by the presence of multiple biological invaders. Wetland management activities typically target invasive plants, but bottom-up responses of higher trophic levels in novel communities are difficult to predict. We surveyed plant and amphibian assemblages at 26 sites enrolled in the Wetlands Reserve Program (WRP) in the Willamette Valley, Oregon to determine the relative importance of plant management, non-native species presence, and surrounding landscape for amphibians across multiple life history stages. Explanatory variables negatively associated with native anuran counts included percent invasive plant cover, invasive bullfrog counts, non-native fish presence, and area of urban land cover. In addition, native anurans were positively associated with WRP site age, suggesting that the benefits of restored wetlands may increase over time. Although invasive plant management provided indirect benefits to native amphibians, the most effective way to enhance native amphibian populations may be through eliminating the strong top-down forces exerted by non-native vertebrates. We also explored the impact of restoration activities on predator/prey dynamics by analyzing bullfrog diet contents. We sampled vegetation and analyzed bullfrog diet contents from 10 WRP wetlands categorized by management intensity and hydrology to determine whether prey consumption patterns (abundance, richness, and % large prey), diet breadth, and dietary community (based on taxonomic and prey size composition) differed among wetlands categorized by management regime and hydroperiod. We found disparities in the diet breadth with respect to wetland categories, with bullfrogs consuming a disproportionate abundance of few prey orders at actively managed sites. Diet breadth could have been influenced by frequent applications of restoration treatments, as invertebrate species richness and abundance is often negatively linked to habitat disturbance. Dietary taxonomic composition also differed between wetland groups, but prey size composition did not. Instead, prey size was strongly influenced by site-level vegetation covariates; large-bodied prey consumption was positively associated with plant species richness. However, diet dry mass was highest in wetlands with high invasive plant cover, suggesting that other factors, such as foraging activity rates, should be considered to fully understand how bullfrogs meet energy demands in managed wetlands. Variation in native and invasive amphibian responses to wetland restoration efforts may provide important information on how habitat structure and composition influence trophic dynamics. Given that the outcomes of plant control on wildlife may not follow planned trajectories in invasive-dominated systems, this research addresses the need for a community approach to assessments of restoration success. Close

• 5. [Article] Exploring water habitats

  Published April 2014. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog

  Citation × Citation Citation Abstract Copy Title: Exploring water habitats Author: Bourdeau, Virginia, Oregon State University. Extension Service Published April 2014. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Title: Exploring water habitats Author: Bourdeau, Virginia, Oregon State University. Extension Service Published April 2014. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog Close

• 6. [Article] Detecting changes in a wetland : using multi-spectral and temporal Landsat in the Upper Noun Valley Drainage Basin-Cameroon

  Since the early 1980s, satellite imagery has been commonly used to detect change in wetlands. The overall objective of this study is to utilize remote sensing and Geographic Information Systems (GIS) technology ...

  Citation × Citation Citation Abstract Copy Title: Detecting changes in a wetland : using multi-spectral and temporal Landsat in the Upper Noun Valley Drainage Basin-Cameroon Author: Ndzeidze, Stephen Koghan Since the early 1980s, satellite imagery has been commonly used to detect change in wetlands. The overall objective of this study is to utilize remote sensing and Geographic Information Systems (GIS) technology to determine the extent of change of the wetland area and of other land use and land cover classes in the Upper Noun drainage basin from 1973 to 2007. Specific objectives were 1) to map land cover and related land use practices within the wetland and surrounding areas of the drainage basin using the supervised maximum likelihood algorithm classification method; 2) to map land use and land cover classes by seasons in order to determine human-induced pressure on the wetland area and the drainage basin using available Landsat MSS, TM and ETM+ imagery; 3) to utilize GIS in confirming and finalizing the land use and land cover classes and delimitation of the Upper Noun drainage basin by incorporating auxiliary data such as settlements and hydrology. The Upper Noun drainage basin is an important wetland that lies within the western high plateau of Cameroon where it supports a wide range of wildlife. The study defines twelve different land cover and land use classes that are grouped into four major categories. The first category is the humid floodplain class that makes up the wetland area, including the floodplain lake (1973), the reservoir, the permanent and seasonally flooded prairies, and irrigated farmlands. The second category consists of the agropastoral classes which are made of upland grazing areas and mixed farming areas. The third category is the montane and semi montane forest zone at elevations above 1,500 - 3,000 m. The fourth category is comprised of major settlements, and settlements with enclosures and openfields. This study is an example of an application of spatio-temporal data in assessing the close relationship existing between humans and their environment. This is a Sub Saharan African community that has a long history of direct dependence on the available resources for its daily livelihood. A detailed physical and historical background is presented to provide a context for spatio-temporal variation discovered through change detection using Landsat imagery without ground truth data. The data analysis reveals considerable change within the Upper Noun drainage basin from 1978 to 2002. Within the wetland area in the floodplain, the reservoir shows evidence of large fluctuations in area since the construction of the Bamendjin dam in 1975. Within the reservoir area, an acute siltation has been observed since 1988 and is increasing in area. A significant drop in area of permanent and seasonally flooded prairies was observed. Irrigated farmland areas also show downward trends from 1988 to 2002. Concerning the agropastoral landscape, the upland grazing areas showed a general drop in area, while the mixed farming area increased from 1978 to 2002. The montane forest also decreased in area; however, it appeared to have recovered slightly in 2002 following the successful implementation of the Kilum/Ijim community forest management project. Settlement also showed some expansion in area as a result of growth of most enclosures and openfields to larger villages and major settlements. This study thus provides base data for monitoring human impacts on the Upper Noun drainage basin and its natural habitats, especially within and around the wetland. Title: Detecting changes in a wetland : using multi-spectral and temporal Landsat in the Upper Noun Valley Drainage Basin-Cameroon Author: Ndzeidze, Stephen Koghan Since the early 1980s, satellite imagery has been commonly used to detect change in wetlands. The overall objective of this study is to utilize remote sensing and Geographic Information Systems (GIS) technology to determine the extent of change of the wetland area and of other land use and land cover classes in the Upper Noun drainage basin from 1973 to 2007. Specific objectives were 1) to map land cover and related land use practices within the wetland and surrounding areas of the drainage basin using the supervised maximum likelihood algorithm classification method; 2) to map land use and land cover classes by seasons in order to determine human-induced pressure on the wetland area and the drainage basin using available Landsat MSS, TM and ETM+ imagery; 3) to utilize GIS in confirming and finalizing the land use and land cover classes and delimitation of the Upper Noun drainage basin by incorporating auxiliary data such as settlements and hydrology. The Upper Noun drainage basin is an important wetland that lies within the western high plateau of Cameroon where it supports a wide range of wildlife. The study defines twelve different land cover and land use classes that are grouped into four major categories. The first category is the humid floodplain class that makes up the wetland area, including the floodplain lake (1973), the reservoir, the permanent and seasonally flooded prairies, and irrigated farmlands. The second category consists of the agropastoral classes which are made of upland grazing areas and mixed farming areas. The third category is the montane and semi montane forest zone at elevations above 1,500 - 3,000 m. The fourth category is comprised of major settlements, and settlements with enclosures and openfields. This study is an example of an application of spatio-temporal data in assessing the close relationship existing between humans and their environment. This is a Sub Saharan African community that has a long history of direct dependence on the available resources for its daily livelihood. A detailed physical and historical background is presented to provide a context for spatio-temporal variation discovered through change detection using Landsat imagery without ground truth data. The data analysis reveals considerable change within the Upper Noun drainage basin from 1978 to 2002. Within the wetland area in the floodplain, the reservoir shows evidence of large fluctuations in area since the construction of the Bamendjin dam in 1975. Within the reservoir area, an acute siltation has been observed since 1988 and is increasing in area. A significant drop in area of permanent and seasonally flooded prairies was observed. Irrigated farmland areas also show downward trends from 1988 to 2002. Concerning the agropastoral landscape, the upland grazing areas showed a general drop in area, while the mixed farming area increased from 1978 to 2002. The montane forest also decreased in area; however, it appeared to have recovered slightly in 2002 following the successful implementation of the Kilum/Ijim community forest management project. Settlement also showed some expansion in area as a result of growth of most enclosures and openfields to larger villages and major settlements. This study thus provides base data for monitoring human impacts on the Upper Noun drainage basin and its natural habitats, especially within and around the wetland. Close

• 7. [Article] Seasonal movement, residency, and migration patterns of Wilson's Snipe (Gallinago delicata) across the annual cycle in the Willamette Valley of Oregon.

  Studies of avian movement ecology afford essential insights regarding species' life histories, population dynamics, habitat and resource requirements, and other ecological relationships. While it is widely ...

  Citation × Citation Citation Abstract Copy Title: Seasonal movement, residency, and migration patterns of Wilson's Snipe (Gallinago delicata) across the annual cycle in the Willamette Valley of Oregon. Author: Cline, Brittany B. Studies of avian movement ecology afford essential insights regarding species' life histories, population dynamics, habitat and resource requirements, and other ecological relationships. While it is widely recognized that events in different stages of the annual cycle have important implications for processes in avian ecology, evolution, and conservation, challenges associated with quantifying migratory connectivity frequently constrain annual-cycle approaches to the study of avian movement. The majority of cross-seasonal movement studies have been conducted to either (1) establish linkages between geographically distinct wintering, breeding and migratory stopover locations; or (2) assess site fidelity and movement within fractions of the annual cycle (i.e. individual seasons). Far fewer studies employ annual-cycle approaches to investigate how local and regional movement patterns of individuals change seasonally within an area of breeding and wintering-range overlap. Within western Oregon’s Willamette Valley in 2007, I quantified the intra- and inter-seasonal movement patterns, fidelity (regional/local), and migratory strategies of 37 radio-marked Wilson’s Snipe (Gallinago delicata) to elucidate residency status in a region of breeding and wintering-range overlap. Available evidence indicated the potential for a variety of possible migratory behaviors for this relatively understudied migratory species; results revealed that the group monitored constituted winter residents (74%), winter transients (14%), summer residents (9%), and one year-round resident breeder (3%). Findings indicated a lack of connectivity between populations captured during winter and summer, scant evidence of partial migration (one year-round resident), as well as the first documentation of between-season fidelity of snipe to the region (return of winter resident in subsequent fall). Spring migration chronology of radio-marked winter residents indicated a strong sex differential in timing of migration, with males departing an average of 9.68 days earlier than females (20.11 days including winter transients). In contrast, fall migration patterns were suggestive of inverse chronology (females departing before males). Male-biased winter sex ratios were consistent with observed latitudinal clines for other nonbreeding shorebird populations. The protracted spring migration periods resulted in gradual dispersal consistent with energy minimization migration strategies. Across seasons, the extent of movements and use of multiple wetland sites suggested that snipe were capable of exploratory movements, but more regularly perceived local and fine-scale segments of the landscape as connected. There were no differences in the areal extent of individual home-ranges, number of sites visited, individual mobility, or distances detected from capture sites by individual sex (or interaction of sex × season). However, movements differed significantly by season and residency, with individuals exhibiting contracted movements during late winter, and most expansive movements during precipitation-limited periods (late spring, summer, fall 2007). Mean home-range size was 3.52 ± 0.93 km2 (100% MCP) and 1.57 ± 0.42 km2 (95% fixed kernel), and did not vary by sex; however, home-range varied markedly by season (range 100% MCP = 1.04 – 7.56 km2). Overall results indicated variable fidelity patterns (e.g., prolonged periods of within-season residency, transient behavior, between-season fidelity, partial migration), which were indicative of a complex regional population structure. Wilson’s Snipe demonstrated striking differences in movement patterns, vagility and local site fidelity across seasons in the Willamette Valley, while previous studies of shorebird movement and habitat use in the region focused solely on winter and precipitation-copious periods. Furthermore, by highlighting the seasonal changes in snipe movement metrics, this study provides the first cross-seasonal profile of a shorebird species’ space-use in a region of breeding and wintering-range overlap. Results provide insight on the regional and local fidelity and movement patterns of shorebirds in a spatiotemporally dynamic wetland landscape, across multiple seasons. Furthermore, findings indicate that single-season approaches to wetland management in the region present the risk of mischaracterizing species’ spatial requirements, and highlight the need to consider: (1) cross-seasonal effects, and (2) inter-specific differences in shorebird life histories when developing regional wetland conservation plans. Title: Seasonal movement, residency, and migration patterns of Wilson's Snipe (Gallinago delicata) across the annual cycle in the Willamette Valley of Oregon. Author: Cline, Brittany B. Studies of avian movement ecology afford essential insights regarding species' life histories, population dynamics, habitat and resource requirements, and other ecological relationships. While it is widely recognized that events in different stages of the annual cycle have important implications for processes in avian ecology, evolution, and conservation, challenges associated with quantifying migratory connectivity frequently constrain annual-cycle approaches to the study of avian movement. The majority of cross-seasonal movement studies have been conducted to either (1) establish linkages between geographically distinct wintering, breeding and migratory stopover locations; or (2) assess site fidelity and movement within fractions of the annual cycle (i.e. individual seasons). Far fewer studies employ annual-cycle approaches to investigate how local and regional movement patterns of individuals change seasonally within an area of breeding and wintering-range overlap. Within western Oregon’s Willamette Valley in 2007, I quantified the intra- and inter-seasonal movement patterns, fidelity (regional/local), and migratory strategies of 37 radio-marked Wilson’s Snipe (Gallinago delicata) to elucidate residency status in a region of breeding and wintering-range overlap. Available evidence indicated the potential for a variety of possible migratory behaviors for this relatively understudied migratory species; results revealed that the group monitored constituted winter residents (74%), winter transients (14%), summer residents (9%), and one year-round resident breeder (3%). Findings indicated a lack of connectivity between populations captured during winter and summer, scant evidence of partial migration (one year-round resident), as well as the first documentation of between-season fidelity of snipe to the region (return of winter resident in subsequent fall). Spring migration chronology of radio-marked winter residents indicated a strong sex differential in timing of migration, with males departing an average of 9.68 days earlier than females (20.11 days including winter transients). In contrast, fall migration patterns were suggestive of inverse chronology (females departing before males). Male-biased winter sex ratios were consistent with observed latitudinal clines for other nonbreeding shorebird populations. The protracted spring migration periods resulted in gradual dispersal consistent with energy minimization migration strategies. Across seasons, the extent of movements and use of multiple wetland sites suggested that snipe were capable of exploratory movements, but more regularly perceived local and fine-scale segments of the landscape as connected. There were no differences in the areal extent of individual home-ranges, number of sites visited, individual mobility, or distances detected from capture sites by individual sex (or interaction of sex × season). However, movements differed significantly by season and residency, with individuals exhibiting contracted movements during late winter, and most expansive movements during precipitation-limited periods (late spring, summer, fall 2007). Mean home-range size was 3.52 ± 0.93 km2 (100% MCP) and 1.57 ± 0.42 km2 (95% fixed kernel), and did not vary by sex; however, home-range varied markedly by season (range 100% MCP = 1.04 – 7.56 km2). Overall results indicated variable fidelity patterns (e.g., prolonged periods of within-season residency, transient behavior, between-season fidelity, partial migration), which were indicative of a complex regional population structure. Wilson’s Snipe demonstrated striking differences in movement patterns, vagility and local site fidelity across seasons in the Willamette Valley, while previous studies of shorebird movement and habitat use in the region focused solely on winter and precipitation-copious periods. Furthermore, by highlighting the seasonal changes in snipe movement metrics, this study provides the first cross-seasonal profile of a shorebird species’ space-use in a region of breeding and wintering-range overlap. Results provide insight on the regional and local fidelity and movement patterns of shorebirds in a spatiotemporally dynamic wetland landscape, across multiple seasons. Furthermore, findings indicate that single-season approaches to wetland management in the region present the risk of mischaracterizing species’ spatial requirements, and highlight the need to consider: (1) cross-seasonal effects, and (2) inter-specific differences in shorebird life histories when developing regional wetland conservation plans. Close

• 8. [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

• 9. [Article] Watercourse-Upland and Elevational Gradients in Spring Vegetation of a Mojave-Great Basin Desert Landscape

  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 the Natural ...

  Citation × Citation Citation Abstract Copy Title: Watercourse-Upland and Elevational Gradients in Spring Vegetation of a Mojave-Great Basin Desert Landscape Author: Spencer, Jessica E., McPherson, Sara L., Abella, Scott R., Craig, Jill E. 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 the Natural Areas Association and can be found at: http://www.bioone.org/loi/naar. Title: Watercourse-Upland and Elevational Gradients in Spring Vegetation of a Mojave-Great Basin Desert Landscape Author: Spencer, Jessica E., McPherson, Sara L., Abella, Scott R., Craig, Jill E. 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 the Natural Areas Association and can be found at: http://www.bioone.org/loi/naar. Close

• 10. [Article] Sphagnum fens on the Oregon coast: diminishing habitat and need for management

  Report to U.S. Fish and Wildlife Service, Region 1, Portland, Oregon

  Citation × Citation Citation Abstract Copy Title: Sphagnum fens on the Oregon coast: diminishing habitat and need for management Author: Christy, John A. Report to U.S. Fish and Wildlife Service, Region 1, Portland, Oregon Title: Sphagnum fens on the Oregon coast: diminishing habitat and need for management Author: Christy, John A. Report to U.S. Fish and Wildlife Service, Region 1, Portland, Oregon Close