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• 1. [Article] Comparison of Fish Assemblages in Restored and Natural Mangrove Habitats Along an Urban Shoreline

  The installation of living shorelines is one strategy used to ameliorate habitat degradation along developed coastlines. In this process, existing hard structures, such as sea walls and riprap revetments, ...

  Citation × Citation Citation Abstract Copy Title: Comparison of Fish Assemblages in Restored and Natural Mangrove Habitats Along an Urban Shoreline Author: Peters, Joseph R., Yeager, Laura A., Layman, Craig A. Year: 2015 The installation of living shorelines is one strategy used to ameliorate habitat degradation along developed coastlines. In this process, existing hard structures, such as sea walls and riprap revetments, are supplemented with habitat forming species, e.g., oysters and mangrove trees, to improve habitat quality and function. Shoreline restorations in Biscayne Bay, Florida, USA, often utilize red mangroves, Rhizophora mangle (Linneaus, 1753), in addition to riprap revetments, to help stabilize the shoreline. This riprap-mangrove habitat provides structure for marine organisms to utilize and is believed to improve shoreline habitats in areas previously cleared of mangroves. We examined whether habitat provisioning was similar between restored mangrove habitat with the inclusion of riprap boulders and natural mangrove shorelines. We compared fish assemblages between natural mangrove and riprapmangrove habitats within two areas of northern Biscayne Bay. Fish community structure and certain benthic cover types varied between mangroves and riprap-mangrove habitats. Total fish abundance was greater in mangrove habitat, while taxonomic richness was highest in riprap-mangrove sites in the northern part of the bay. Our findings suggest that fish assemblages and community structure are different between these habitat types, although the geographic context may mediate the effect of habitat type. Therefore, it is likely that these restored mangroves provide different ecological services than unaltered mangrove shorelines. Title: Comparison of Fish Assemblages in Restored and Natural Mangrove Habitats Along an Urban Shoreline Author: Peters, Joseph R., Yeager, Laura A., Layman, Craig A. Year: 2015 The installation of living shorelines is one strategy used to ameliorate habitat degradation along developed coastlines. In this process, existing hard structures, such as sea walls and riprap revetments, are supplemented with habitat forming species, e.g., oysters and mangrove trees, to improve habitat quality and function. Shoreline restorations in Biscayne Bay, Florida, USA, often utilize red mangroves, Rhizophora mangle (Linneaus, 1753), in addition to riprap revetments, to help stabilize the shoreline. This riprap-mangrove habitat provides structure for marine organisms to utilize and is believed to improve shoreline habitats in areas previously cleared of mangroves. We examined whether habitat provisioning was similar between restored mangrove habitat with the inclusion of riprap boulders and natural mangrove shorelines. We compared fish assemblages between natural mangrove and riprapmangrove habitats within two areas of northern Biscayne Bay. Fish community structure and certain benthic cover types varied between mangroves and riprap-mangrove habitats. Total fish abundance was greater in mangrove habitat, while taxonomic richness was highest in riprap-mangrove sites in the northern part of the bay. Our findings suggest that fish assemblages and community structure are different between these habitat types, although the geographic context may mediate the effect of habitat type. Therefore, it is likely that these restored mangroves provide different ecological services than unaltered mangrove shorelines. Close

• 2. [Article] Fish Species Introductions Provide Novel Insights into the Patterns and Drivers of Phylogenetic Structure in Freshwaters

  Despite long-standing interest of terrestrial ecologists, freshwater ecosystems are a fertile, yet unappreciated, testing ground for applying community phylogenetics to uncover mechanisms of species assembly. ...

  Citation × Citation Citation Abstract Copy Title: Fish Species Introductions Provide Novel Insights into the Patterns and Drivers of Phylogenetic Structure in Freshwaters Author: Strecker, Angela L., Olden, Julian D. Year: 2014 Despite long-standing interest of terrestrial ecologists, freshwater ecosystems are a fertile, yet unappreciated, testing ground for applying community phylogenetics to uncover mechanisms of species assembly. We quantify phylogenetic clustering and overdispersion of native and non-native fishes of a large river basin in the American Southwest to test for the mechanisms (environmental filtering versus competitive exclusion) and spatial scales influencing community structure. Contrary to expectations, non-native species were phylogenetically clustered and related to natural environmental conditions, whereas native species were not phylogenetically structured, likely reflecting human-related changes to the basin. The species that are most invasive (in terms of ecological impacts) tended to be the most phylogenetically divergent from natives across watersheds, but not within watersheds, supporting the hypothesis that Darwin's naturalization conundrum is driven by the spatial scale. Phylogenetic distinctiveness may facilitate non-native establishment at regional scales, but environmental filtering restricts local membership to closely related species with physiological tolerances for current environments. By contrast, native species may have been phylogenetically clustered in historical times, but species loss from contemporary populations by anthropogenic activities has likely shaped the phylogenetic signal. Our study implies that fundamental mechanisms of community assembly have changed, with fundamental consequences for the biogeography of both native and non-native species. Title: Fish Species Introductions Provide Novel Insights into the Patterns and Drivers of Phylogenetic Structure in Freshwaters Author: Strecker, Angela L., Olden, Julian D. Year: 2014 Despite long-standing interest of terrestrial ecologists, freshwater ecosystems are a fertile, yet unappreciated, testing ground for applying community phylogenetics to uncover mechanisms of species assembly. We quantify phylogenetic clustering and overdispersion of native and non-native fishes of a large river basin in the American Southwest to test for the mechanisms (environmental filtering versus competitive exclusion) and spatial scales influencing community structure. Contrary to expectations, non-native species were phylogenetically clustered and related to natural environmental conditions, whereas native species were not phylogenetically structured, likely reflecting human-related changes to the basin. The species that are most invasive (in terms of ecological impacts) tended to be the most phylogenetically divergent from natives across watersheds, but not within watersheds, supporting the hypothesis that Darwin's naturalization conundrum is driven by the spatial scale. Phylogenetic distinctiveness may facilitate non-native establishment at regional scales, but environmental filtering restricts local membership to closely related species with physiological tolerances for current environments. By contrast, native species may have been phylogenetically clustered in historical times, but species loss from contemporary populations by anthropogenic activities has likely shaped the phylogenetic signal. Our study implies that fundamental mechanisms of community assembly have changed, with fundamental consequences for the biogeography of both native and non-native species. Close

• 3. [Article] Factors Influencing the Survival of Outmigrating Juvenile Salmonids Through Multiple Dam Passages: An Individual-Based Approach

  Substantial declines of Pacific salmon populations have occurred over the past several decades related to large-scale anthropogenic and climatic changes in freshwater and marine environments. In the Columbia ...

  Citation × Citation Citation Abstract Copy Title: Factors Influencing the Survival of Outmigrating Juvenile Salmonids Through Multiple Dam Passages: An Individual-Based Approach Author: Elder, Timothy, Woodley, Christa M., Weiland, Mark A., Strecker, Angela L. Year: 2016 Substantial declines of Pacific salmon populations have occurred over the past several decades related to large-scale anthropogenic and climatic changes in freshwater and marine environments. In the Columbia River Basin, migrating juvenile salmonids may pass as many as eight large-scale hydropower projects before reaching the ocean; however, the cumulative effects of multiple dam passages are largely unknown. Using acoustic transmitters and an extensive system of hydrophone arrays in the Lower Columbia River, we calculated the survival of yearling Chinook salmon (Oncorhynchus tshawytscha) and steelhead (O. mykiss) passing one, two, or three dams. We applied a unique index of biological characteristics and environmental exposures, experienced by each fish individually as it migrated downstream, in order to examine which factors most influence salmonid survival. High outflow volumes led to involuntary spill in 2011 and created an environment of supersaturated dissolved gas concentrations. In this environment, migrating smolt survival was strongly influenced by barometric pressure, fish velocity, and water temperature. The effect of these variables on survival was compounded by multiple dam passages compared to fish passing a single dam. Despite spatial isolation between dams in the Lower Columbia River hydrosystem, migrating smolt appear to experience cumulative effects akin to a press disturbance. In general, Chinook salmon and steelhead respond similarly in terms of survival rates and responses to altered environmental conditions. Management actions that limit dissolved gas concentrations in years of high flow will benefit migrating salmonids at this life stage. Title: Factors Influencing the Survival of Outmigrating Juvenile Salmonids Through Multiple Dam Passages: An Individual-Based Approach Author: Elder, Timothy, Woodley, Christa M., Weiland, Mark A., Strecker, Angela L. Year: 2016 Substantial declines of Pacific salmon populations have occurred over the past several decades related to large-scale anthropogenic and climatic changes in freshwater and marine environments. In the Columbia River Basin, migrating juvenile salmonids may pass as many as eight large-scale hydropower projects before reaching the ocean; however, the cumulative effects of multiple dam passages are largely unknown. Using acoustic transmitters and an extensive system of hydrophone arrays in the Lower Columbia River, we calculated the survival of yearling Chinook salmon (Oncorhynchus tshawytscha) and steelhead (O. mykiss) passing one, two, or three dams. We applied a unique index of biological characteristics and environmental exposures, experienced by each fish individually as it migrated downstream, in order to examine which factors most influence salmonid survival. High outflow volumes led to involuntary spill in 2011 and created an environment of supersaturated dissolved gas concentrations. In this environment, migrating smolt survival was strongly influenced by barometric pressure, fish velocity, and water temperature. The effect of these variables on survival was compounded by multiple dam passages compared to fish passing a single dam. Despite spatial isolation between dams in the Lower Columbia River hydrosystem, migrating smolt appear to experience cumulative effects akin to a press disturbance. In general, Chinook salmon and steelhead respond similarly in terms of survival rates and responses to altered environmental conditions. Management actions that limit dissolved gas concentrations in years of high flow will benefit migrating salmonids at this life stage. Close

• 4. [Article] Emerging Contaminants in Oregon Coastal Waters: Hotspots, Landscape Drivers and Synergistic Effects on Bivalves

  This presentation focuses on the following research questions: Types and levels of contaminants of emerging concern (CECs) in Oregon’s coastal ocean? Levels of CECs in native and commercial oysters? ...

  Citation × Citation Citation Abstract Copy Title: Emerging Contaminants in Oregon Coastal Waters: Hotspots, Landscape Drivers and Synergistic Effects on Bivalves Author: Granek, Elise F., Fish, William, Strecker, Angela L. Year: 2013 This presentation focuses on the following research questions: Types and levels of contaminants of emerging concern (CECs) in Oregon’s coastal ocean? Levels of CECs in native and commercial oysters? Ecological effects (growth, reproductive output, etc.) of these contaminants in marine bivalves? Title: Emerging Contaminants in Oregon Coastal Waters: Hotspots, Landscape Drivers and Synergistic Effects on Bivalves Author: Granek, Elise F., Fish, William, Strecker, Angela L. Year: 2013 This presentation focuses on the following research questions: Types and levels of contaminants of emerging concern (CECs) in Oregon’s coastal ocean? Levels of CECs in native and commercial oysters? Ecological effects (growth, reproductive output, etc.) of these contaminants in marine bivalves? Close

• 5. [Article] Effects of Pharmaceuticals and Personal Care Products on Marine Organisms: From Single-Species Studies to an Ecosystem-Based Approach

  Pharmaceuticals and personal care products (PPCPs) are contaminants of emerging concern that are increasing in use and have demonstrated negative effects on aquatic organisms. There is a growing body of ...

  Citation × Citation Citation Abstract Copy Title: Effects of Pharmaceuticals and Personal Care Products on Marine Organisms: From Single-Species Studies to an Ecosystem-Based Approach Author: Prichard, Emma C, Granek, Elise F. Year: 2016 Pharmaceuticals and personal care products (PPCPs) are contaminants of emerging concern that are increasing in use and have demonstrated negative effects on aquatic organisms. There is a growing body of literature reporting the effects of PPCPs on freshwater organisms, but studies on the effects of PPCPs to marine and estuarine organisms are limited. Among effect studies, the vast majority examines subcellular or cellular effects, with far fewer studies examining organismal- and community-level effects. We reviewed the current published literature on marine and estuarine algae, invertebrates, fish, and mammals exposed to PPCPs, in order to expand upon current reviews. This paper builds on previous reviews of PPCP contamination in marine environments, filling prior literature gaps and adding consideration of ecosystem function and level of knowledge across marine habitat types. Finally, we reviewed and compiled data gaps suggested by current researchers and reviewers and propose a multi-level model to expand the focus of current PPCP research beyond laboratory studies. This model includes examination of direct ecological effects including food web and disease dynamics, biodiversity, community composition, and other ecosystem-level indicators of contaminant-driven change. Title: Effects of Pharmaceuticals and Personal Care Products on Marine Organisms: From Single-Species Studies to an Ecosystem-Based Approach Author: Prichard, Emma C, Granek, Elise F. Year: 2016 Pharmaceuticals and personal care products (PPCPs) are contaminants of emerging concern that are increasing in use and have demonstrated negative effects on aquatic organisms. There is a growing body of literature reporting the effects of PPCPs on freshwater organisms, but studies on the effects of PPCPs to marine and estuarine organisms are limited. Among effect studies, the vast majority examines subcellular or cellular effects, with far fewer studies examining organismal- and community-level effects. We reviewed the current published literature on marine and estuarine algae, invertebrates, fish, and mammals exposed to PPCPs, in order to expand upon current reviews. This paper builds on previous reviews of PPCP contamination in marine environments, filling prior literature gaps and adding consideration of ecosystem function and level of knowledge across marine habitat types. Finally, we reviewed and compiled data gaps suggested by current researchers and reviewers and propose a multi-level model to expand the focus of current PPCP research beyond laboratory studies. This model includes examination of direct ecological effects including food web and disease dynamics, biodiversity, community composition, and other ecosystem-level indicators of contaminant-driven change. Close

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

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

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

• 7. [Article] Understanding the Links Between Cyanobacteria Physiology and Hydrodynamics may Help Find Adaption Strategies for Toxic Blooms

  Even though we are managing lakes to decrease algal blooms overall, harmful algal blooms seem to be showing up more and more frequently. Although the word “blooms” connotes dominance and rapid growth, ...

  Citation × Citation Citation Abstract Copy Title: Understanding the Links Between Cyanobacteria Physiology and Hydrodynamics may Help Find Adaption Strategies for Toxic Blooms Author: Rueter, John Year: 2016 Even though we are managing lakes to decrease algal blooms overall, harmful algal blooms seem to be showing up more and more frequently. Although the word “blooms” connotes dominance and rapid growth, dangerous accumulations of cyanobacteria can occur because of combinations of physiological advantages and particular weather and hydrodynamic conditions. I am particularly interested in specific conditions that might favor Aphanizomenon versus those that might favor Microcystis in Upper Klamath and Agency Lakes. Aphanizomenon is a nuisance and large blooms can lead to oxygen depletion and fish deaths. Microcystis can both be a nuisance and is toxic. The comparison of the physiologies of these two cyanobacterial strains could lead to an understanding of both short term adaptation and mitigation tactics as well as long term lake restoration strategies. Ideally, we would like to employ lake restoration strategies and see constant improvement leading to safer and cleaner water. However, either because of threshold effects or ineffective lake management approaches, we might have to take short-term manipulations that can reduce local accumulations of cyanobacteria to protect the health of humans and other species. These short term tactics must have three characteristics: First, we need to find mitigation techniques that might knock down or stall a bloom of algae from occurring. Second, we have to have ways to model and monitor these manipulations over relevant time and space scales. Third, any short-term techniques we employ should not substantial interfere with the long term goals of lake restoration, i.e. the quick fix shouldn’t undermine the solving the problem. I will present several potential short-term solutions based algal physiology and hydrodynamics. Then I will describe how we have used temperature datalogging (10 minute intervals) and high-resolution transects (1 meter spatial resolution) to understand impacts on accumulation processes. Then finally, I will describe a framework for supporting fast and cheap methods to adapt to cyanobacteria accumulations that don’t result in unintended consequences or interfere with lake restoration efforts. Title: Understanding the Links Between Cyanobacteria Physiology and Hydrodynamics may Help Find Adaption Strategies for Toxic Blooms Author: Rueter, John Year: 2016 Even though we are managing lakes to decrease algal blooms overall, harmful algal blooms seem to be showing up more and more frequently. Although the word “blooms” connotes dominance and rapid growth, dangerous accumulations of cyanobacteria can occur because of combinations of physiological advantages and particular weather and hydrodynamic conditions. I am particularly interested in specific conditions that might favor Aphanizomenon versus those that might favor Microcystis in Upper Klamath and Agency Lakes. Aphanizomenon is a nuisance and large blooms can lead to oxygen depletion and fish deaths. Microcystis can both be a nuisance and is toxic. The comparison of the physiologies of these two cyanobacterial strains could lead to an understanding of both short term adaptation and mitigation tactics as well as long term lake restoration strategies. Ideally, we would like to employ lake restoration strategies and see constant improvement leading to safer and cleaner water. However, either because of threshold effects or ineffective lake management approaches, we might have to take short-term manipulations that can reduce local accumulations of cyanobacteria to protect the health of humans and other species. These short term tactics must have three characteristics: First, we need to find mitigation techniques that might knock down or stall a bloom of algae from occurring. Second, we have to have ways to model and monitor these manipulations over relevant time and space scales. Third, any short-term techniques we employ should not substantial interfere with the long term goals of lake restoration, i.e. the quick fix shouldn’t undermine the solving the problem. I will present several potential short-term solutions based algal physiology and hydrodynamics. Then I will describe how we have used temperature datalogging (10 minute intervals) and high-resolution transects (1 meter spatial resolution) to understand impacts on accumulation processes. Then finally, I will describe a framework for supporting fast and cheap methods to adapt to cyanobacteria accumulations that don’t result in unintended consequences or interfere with lake restoration efforts. Close

• 8. [Article] Increased Taxonomic and Functional Similarity Does Not Increase the Trophic Similarity of Communities

  Aim: Despite a long-standing research interest in the association between the biodiversity (i.e. taxonomic and functional composition) and trophic structure of communities, our understanding of the relationship ...

  Citation × Citation Citation Abstract Copy Title: Increased Taxonomic and Functional Similarity Does Not Increase the Trophic Similarity of Communities Author: Pool, Thomas K., Cucherousset, Julien, Boulêtreau, Stéphanie, Villéger, Sébastien, Strecker, Angela L., Grenouillet, Gaël Year: 2015 Aim: Despite a long-standing research interest in the association between the biodiversity (i.e. taxonomic and functional composition) and trophic structure of communities, our understanding of the relationship remains limited. Community assembly theory predicts that niche partitioning will result in communities with a diverse array of functional traits, which in turn may facilitate a correspondingly diverse array of trophic interactions that define the trophic niche of those communities. The aim of our study is to test this prediction. Methods: We built a database composed of functional traits and stable isotope values (δ13C and δ15N) for 63 freshwater fish communities containing 109 species in 34 lentic and 29 lotic ecosystems. First, using linear mixed models (i.e. an alpha-diversity approach), we tested whether the taxonomic diversity of communities was positively associated with their functional diversity and if their functional diversity was positively associated with their trophic diversity. Second, we assessed the taxonomic, functional and trophic similarity of communities using multiple regression on distance matrices (MRM) and their respective ‘turnover’ and ‘nestedness-resultant’ components to test if the taxonomic similarity of communities was positively correlated with their functional similarity and if their functional similarity was positively associated with their trophic similarity (i.e. a beta-diversity approach). Results: We found that the functional diversity of communities increased as their taxonomic diversity increased. Similarly, the trophic diversity of communities increased as their functional diversity increased. The pairwise taxonomic and functional similarity of communities were also positively associated, but there was a weak relationship between the functional and trophic similarities of communities. Main conclusions: Our study demonstrates that communities with similar functional characteristics can have disparate food web structures, suggesting that additional site-specific factors influence community variation in trophic niche geometry. Determining the relative importance of functional characteristics and site-specific factors in shaping trophic interactions is crucial for a better understanding of how future species loss and species introductions will affect food web structure and ecosystem functioning. Title: Increased Taxonomic and Functional Similarity Does Not Increase the Trophic Similarity of Communities Author: Pool, Thomas K., Cucherousset, Julien, Boulêtreau, Stéphanie, Villéger, Sébastien, Strecker, Angela L., Grenouillet, Gaël Year: 2015 Aim: Despite a long-standing research interest in the association between the biodiversity (i.e. taxonomic and functional composition) and trophic structure of communities, our understanding of the relationship remains limited. Community assembly theory predicts that niche partitioning will result in communities with a diverse array of functional traits, which in turn may facilitate a correspondingly diverse array of trophic interactions that define the trophic niche of those communities. The aim of our study is to test this prediction. Methods: We built a database composed of functional traits and stable isotope values (δ13C and δ15N) for 63 freshwater fish communities containing 109 species in 34 lentic and 29 lotic ecosystems. First, using linear mixed models (i.e. an alpha-diversity approach), we tested whether the taxonomic diversity of communities was positively associated with their functional diversity and if their functional diversity was positively associated with their trophic diversity. Second, we assessed the taxonomic, functional and trophic similarity of communities using multiple regression on distance matrices (MRM) and their respective ‘turnover’ and ‘nestedness-resultant’ components to test if the taxonomic similarity of communities was positively correlated with their functional similarity and if their functional similarity was positively associated with their trophic similarity (i.e. a beta-diversity approach). Results: We found that the functional diversity of communities increased as their taxonomic diversity increased. Similarly, the trophic diversity of communities increased as their functional diversity increased. The pairwise taxonomic and functional similarity of communities were also positively associated, but there was a weak relationship between the functional and trophic similarities of communities. Main conclusions: Our study demonstrates that communities with similar functional characteristics can have disparate food web structures, suggesting that additional site-specific factors influence community variation in trophic niche geometry. Determining the relative importance of functional characteristics and site-specific factors in shaping trophic interactions is crucial for a better understanding of how future species loss and species introductions will affect food web structure and ecosystem functioning. Close

• 9. [Article] Siltcoos Lake Nonpoint Source Implementation Grant: Water Quality Conditions and Nutrient Sources

  Siltcoos Lake is a large (1280 hectares), shallow (mean depth 3.3 m; maximum depth 6.7 m) lake located on the Central Oregon Coast, just south of Florence and bordered by Dunes City, Oregon. The outflow ...

  Citation × Citation Citation Abstract Copy Title: Siltcoos Lake Nonpoint Source Implementation Grant: Water Quality Conditions and Nutrient Sources Author: Sytsma, Mark D., Miller, Rich Year: 2010 Siltcoos Lake is a large (1280 hectares), shallow (mean depth 3.3 m; maximum depth 6.7 m) lake located on the Central Oregon Coast, just south of Florence and bordered by Dunes City, Oregon. The outflow and water level of Siltcoos Lake is regulated by a dam on the Siltcoos River 4 km upstream from the Pacific. Several permanent streams feed the lake from its 176 square kilometer watershed including Fiddle Creek, Maple Creek, and Woahink Creek, the outflow from Woahink Lake. Much of the watershed is forested and used for timber harvest, residential development, and limited agricultural production. The lake is popular for recreational activities, particularly fishing for wild coastal Coho salmon, rainbow trout, cutthroat trout, largemouth bass, bluegill, crappie, and yellow perch (Buckman 2004). The lake is also the domestic drinking water source for approximately 125 of the 1330 residents of Dunes City and numerous residents outside the city limits within Lane and Douglas Counties (LCOG 2002). During the fall of 2007 a dense bloom of the potentially toxigenic blue-green algal species Anabaena planktonica prompted Dunes City, the South Coast Water District, the Lane County Health Department, and the Oregon Department of Human Services to issue an advisory against usage of Siltcoos Lake water for drinking and other domestic use (DHS 2007). Residents dependent upon Siltcoos Lake were forced to find alternate domestic water sources for a total of 52 days. This incident was part of a long history of water quality problems including dense algal growth and excessive growth of the non-native aquatic macrophytes Brazilian elodea (Egeria densa), parrotsfeather (Myriophyllum aquaticum), and two-leaf water milfoil (Myriophyllum heterophyllum) (Pfauth and Sytsma 2005; Johnson et al. 1985; McHugh 1979). Because of the water quality problems, the Oregon Department of Environmental Quality (DEQ) placed the lake the 303(d) list of impaired water bodies; specifically due to violations of the “aquatic weeds and algae” water quality criterion (DEQ 1998; DEQ 2006). Dunes City has acted on water quality concerns for both Siltcoos and Woahink Lakes by issuing a temporary building moratorium (Dunes City 2006a), a septic tank maintenance ordinance (Dunes City 2006b), and an ordinance limiting phosphorus use (Dunes City 2007). Preliminary assessments (Johnson, et al. 1985, LCOG 2002) indicate multiple sources of water quality problems including excess nutrient and/or sediment loading from residential development, poorly functioning on-site septic systems, private forestry and agricultural practices and introductions of non-native aquatic plant species. This report summarizes data collected by Portland State University and project partners between June 2008 and May 2009 to better define water quality conditions within the lake as well as potential nutrient sources. Physical, chemical, and biological data were collected at lake and tributary sites over the one year period. Data were evaluated across sites, depth and the season. The information collected will contribute to total maximum daily load (TMDL) development for the Midcoast Lakes and can be used to identify and prioritize restoration activities in the Siltcoos Lake watershed. Title: Siltcoos Lake Nonpoint Source Implementation Grant: Water Quality Conditions and Nutrient Sources Author: Sytsma, Mark D., Miller, Rich Year: 2010 Siltcoos Lake is a large (1280 hectares), shallow (mean depth 3.3 m; maximum depth 6.7 m) lake located on the Central Oregon Coast, just south of Florence and bordered by Dunes City, Oregon. The outflow and water level of Siltcoos Lake is regulated by a dam on the Siltcoos River 4 km upstream from the Pacific. Several permanent streams feed the lake from its 176 square kilometer watershed including Fiddle Creek, Maple Creek, and Woahink Creek, the outflow from Woahink Lake. Much of the watershed is forested and used for timber harvest, residential development, and limited agricultural production. The lake is popular for recreational activities, particularly fishing for wild coastal Coho salmon, rainbow trout, cutthroat trout, largemouth bass, bluegill, crappie, and yellow perch (Buckman 2004). The lake is also the domestic drinking water source for approximately 125 of the 1330 residents of Dunes City and numerous residents outside the city limits within Lane and Douglas Counties (LCOG 2002). During the fall of 2007 a dense bloom of the potentially toxigenic blue-green algal species Anabaena planktonica prompted Dunes City, the South Coast Water District, the Lane County Health Department, and the Oregon Department of Human Services to issue an advisory against usage of Siltcoos Lake water for drinking and other domestic use (DHS 2007). Residents dependent upon Siltcoos Lake were forced to find alternate domestic water sources for a total of 52 days. This incident was part of a long history of water quality problems including dense algal growth and excessive growth of the non-native aquatic macrophytes Brazilian elodea (Egeria densa), parrotsfeather (Myriophyllum aquaticum), and two-leaf water milfoil (Myriophyllum heterophyllum) (Pfauth and Sytsma 2005; Johnson et al. 1985; McHugh 1979). Because of the water quality problems, the Oregon Department of Environmental Quality (DEQ) placed the lake the 303(d) list of impaired water bodies; specifically due to violations of the “aquatic weeds and algae” water quality criterion (DEQ 1998; DEQ 2006). Dunes City has acted on water quality concerns for both Siltcoos and Woahink Lakes by issuing a temporary building moratorium (Dunes City 2006a), a septic tank maintenance ordinance (Dunes City 2006b), and an ordinance limiting phosphorus use (Dunes City 2007). Preliminary assessments (Johnson, et al. 1985, LCOG 2002) indicate multiple sources of water quality problems including excess nutrient and/or sediment loading from residential development, poorly functioning on-site septic systems, private forestry and agricultural practices and introductions of non-native aquatic plant species. This report summarizes data collected by Portland State University and project partners between June 2008 and May 2009 to better define water quality conditions within the lake as well as potential nutrient sources. Physical, chemical, and biological data were collected at lake and tributary sites over the one year period. Data were evaluated across sites, depth and the season. The information collected will contribute to total maximum daily load (TMDL) development for the Midcoast Lakes and can be used to identify and prioritize restoration activities in the Siltcoos Lake watershed. Close

• 10. [Article] Climate Change, Its Effect on Migration Patterns of the Cackling Goose and White-Fronted Goose in the Willamette Valley, and Implications for Goose Management

  This thesis considers the question of whether climate change is affecting the migration patterns of geese in the Pacific Flyway, specifically cackling geese (Branta hutchinsii minima) and Pacific white-fronted ...

  Citation × Citation Citation Abstract Copy Title: Climate Change, Its Effect on Migration Patterns of the Cackling Goose and White-Fronted Goose in the Willamette Valley, and Implications for Goose Management Author: Warren, Kelly Year: 2010 This thesis considers the question of whether climate change is affecting the migration patterns of geese in the Pacific Flyway, specifically cackling geese (Branta hutchinsii minima) and Pacific white-fronted geese (Anser albifrons frontalis). Ancillary questions that are considered are as follows: • If global warming is affecting these species, what is the nature of the effects? • How are the changes affecting the human environment and what can be done about these effects? In 1994, the majority of the cackler population in the Pacific Flyway began to winter in Oregon’s Willamette Valley rather than in their historical wintering areas in California’s Central Valley. In recent years, the Pacific white-fronted goose has shown a change in behavior similar to that of cacklers just before their major shift. The reasons for this shift have not been clear, though climate change, agricultural shifts, or competition with other species were thought to be possible causes. Analyses of historical breeding and wintering surveys, bird band data, harvest data, agricultural data, and climate and weather data were undertaken in the course of this thesis to see if the cause or causes could be identified. The results showed that climate and weather data, i.e. an increase in average annual temperature coupled with occasional severe winters, most closely correlated with the cacklers’ shift northward. The data comparison revealed that there is a direct relationship between cacklers and a warming shift seen on the wintering grounds. There also was a secondary correlation between the northward shift and recent changes in agricultural crops in the Willamette Valley. Substantially less data are available for white-fronts, and the relationship between their recent migration changes and climate and/or other factors is much less clear. The following recommendations for management and further study are aimed at more completely understanding the scope and causes of migration shifts and formulating well-founded management plans for geese in the Pacific Flyway: • Continue research to determine if climate change is causing changes in goose population numbers and behavior. • Expand breeding ground flight surveys to include cacklers and habitat preference to learn how habitat change on the Y-K Delta is altering cackler behavior and breeding success. • Expand radio transmitter studies and collar programs for cacklers in Oregon and Washington to verify northerly wintering shifts. • Expand collar programs for cacklers wintering in the Willamette Valley to determine if the population is continuing to shift northward. • Expand banding programs for white-fronted geese to gather more data about migration patterns. • Develop models that will allow researchers and managers to correlate migration behavior with various environmental factors including climate change in order to: 1) determine which factors are causing migration changes in specific waterfowl populations and 2) allow managers to make changes to management plans in advance of rapid changes. • Inform the public about how it can assist in collar surveys or volunteer for the U.S. Fish and Wildlife Service (USFWS). This will enable USFWS to have more concrete data and give the public an opportunity gain a greater understanding of geese and goose management. • Expand research on urban cackling geese to determine the nature and scope of their effect on the human environment and to devise management strategies. • Research energetics in migrating geese to determine whether the shift in migration patterns has its basis in climate change. • Increase data exchange and coordination among agencies. • Formulate and implement plans at the city and county levels to manage growing numbers of geese in urban areas. • Recognize and anticipate the possibility that goose populations may move into new wintering areas and formulate plans for management of those species. • Implement low cost techniques, such as more liberal bag limits and seasons, hazing, etc., to assist agricultural landowners in decreasing goose-related crop damage. Title: Climate Change, Its Effect on Migration Patterns of the Cackling Goose and White-Fronted Goose in the Willamette Valley, and Implications for Goose Management Author: Warren, Kelly Year: 2010 This thesis considers the question of whether climate change is affecting the migration patterns of geese in the Pacific Flyway, specifically cackling geese (Branta hutchinsii minima) and Pacific white-fronted geese (Anser albifrons frontalis). Ancillary questions that are considered are as follows: • If global warming is affecting these species, what is the nature of the effects? • How are the changes affecting the human environment and what can be done about these effects? In 1994, the majority of the cackler population in the Pacific Flyway began to winter in Oregon’s Willamette Valley rather than in their historical wintering areas in California’s Central Valley. In recent years, the Pacific white-fronted goose has shown a change in behavior similar to that of cacklers just before their major shift. The reasons for this shift have not been clear, though climate change, agricultural shifts, or competition with other species were thought to be possible causes. Analyses of historical breeding and wintering surveys, bird band data, harvest data, agricultural data, and climate and weather data were undertaken in the course of this thesis to see if the cause or causes could be identified. The results showed that climate and weather data, i.e. an increase in average annual temperature coupled with occasional severe winters, most closely correlated with the cacklers’ shift northward. The data comparison revealed that there is a direct relationship between cacklers and a warming shift seen on the wintering grounds. There also was a secondary correlation between the northward shift and recent changes in agricultural crops in the Willamette Valley. Substantially less data are available for white-fronts, and the relationship between their recent migration changes and climate and/or other factors is much less clear. The following recommendations for management and further study are aimed at more completely understanding the scope and causes of migration shifts and formulating well-founded management plans for geese in the Pacific Flyway: • Continue research to determine if climate change is causing changes in goose population numbers and behavior. • Expand breeding ground flight surveys to include cacklers and habitat preference to learn how habitat change on the Y-K Delta is altering cackler behavior and breeding success. • Expand radio transmitter studies and collar programs for cacklers in Oregon and Washington to verify northerly wintering shifts. • Expand collar programs for cacklers wintering in the Willamette Valley to determine if the population is continuing to shift northward. • Expand banding programs for white-fronted geese to gather more data about migration patterns. • Develop models that will allow researchers and managers to correlate migration behavior with various environmental factors including climate change in order to: 1) determine which factors are causing migration changes in specific waterfowl populations and 2) allow managers to make changes to management plans in advance of rapid changes. • Inform the public about how it can assist in collar surveys or volunteer for the U.S. Fish and Wildlife Service (USFWS). This will enable USFWS to have more concrete data and give the public an opportunity gain a greater understanding of geese and goose management. • Expand research on urban cackling geese to determine the nature and scope of their effect on the human environment and to devise management strategies. • Research energetics in migrating geese to determine whether the shift in migration patterns has its basis in climate change. • Increase data exchange and coordination among agencies. • Formulate and implement plans at the city and county levels to manage growing numbers of geese in urban areas. • Recognize and anticipate the possibility that goose populations may move into new wintering areas and formulate plans for management of those species. • Implement low cost techniques, such as more liberal bag limits and seasons, hazing, etc., to assist agricultural landowners in decreasing goose-related crop damage. Close