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• 81. [Image] Klamath River Basin issues and activities

  	Klamath River Basin Issues and Activities: An Overview Summary The Klamath River Basin, an area on the California-Oregon border, has become a focal point for local and national discussions on water ...
  	Citation × Citation Citation Abstract Copy Title: Klamath River Basin issues and activities Author: Kyna Powers Year: 2005, 2008, 2006 Klamath River Basin Issues and Activities: An Overview Summary The Klamath River Basin, an area on the California-Oregon border, has become a focal point for local and national discussions on water management and water scarcity. Water and species management issues were brought to the forefront when severe drought in 2001 exacerbated competition for scarce water resources and generated conflict among several interests - farmers, Indian tribes, commercial and sport fishermen, other recreationists, federal wildlife refuge managers, environmental groups, and state, local, and tribal governments. The conflicts over water distribution and allocation are physically and legally complex, reflecting the varied and sometimes competing uses of limited water supplies in the Basin. For management purposes, the Basin is divided at Iron Gate Dam into the Upper and Lower Basins. As is true in many regions in the West, the federal government plays a prominent role in the Klamath Basin's water management. This role stems from three primary activities: (1) the operation and management of the Bureau of Reclamation's Klamath Water Project and Central Valley Project (e.g., Trinity River dams); (2) management of federal lands in the Basin, including five national wildlife refuges, several national forests, and public lands; and (3) implementation of federal laws, such as the Endangered Species Act (ESA), Clean Water Act (CWA), and National Environmental Policy Act (NEPA). Conflict was sparked in April of 2001 when the Bureau of Reclamation, which has supplied water to farms in the Upper Basin for nearly 100 years, announced that "no water [would] be available" for farms normally receiving water from the Upper Klamath Lake to avoid jeopardizing the existence of three fish species listed as endangered or threatened under the ESA. While some water was subsequently made available to some farmers from other sources (e.g., wells and other Bureau sources), many farmers faced serious hardships. During Reclamation's operations in September of 2002, warm water temperatures and atypically low flows in the lower Klamath contributed to the death of at least 33,000 adult salmonids. This die-off damaged fish stocks and the tribes, commercial fishermen, and recreational anglers that catch Klamath fish. There have been many studies, Biological Opinions, and operating plans over recent years, all of which have been controversial. The events of 2001 and 2002 prompted renewed efforts to resolve water conflicts in the Klamath Basin. Congress has responded to the controversy in a number of ways, including holding oversight hearings and appropriating funds for activities in the area. This report provides an overview of recent conflict in the Klamath Basin, with an emphasis on activities in the Upper Basin, and summarizes some of the activities taking place to improve water supply reliability and fish survival. This report will be updated as events warrant. Title: Klamath River Basin issues and activities Author: Kyna Powers Year: 2005, 2008, 2006 Klamath River Basin Issues and Activities: An Overview Summary The Klamath River Basin, an area on the California-Oregon border, has become a focal point for local and national discussions on water management and water scarcity. Water and species management issues were brought to the forefront when severe drought in 2001 exacerbated competition for scarce water resources and generated conflict among several interests - farmers, Indian tribes, commercial and sport fishermen, other recreationists, federal wildlife refuge managers, environmental groups, and state, local, and tribal governments. The conflicts over water distribution and allocation are physically and legally complex, reflecting the varied and sometimes competing uses of limited water supplies in the Basin. For management purposes, the Basin is divided at Iron Gate Dam into the Upper and Lower Basins. As is true in many regions in the West, the federal government plays a prominent role in the Klamath Basin's water management. This role stems from three primary activities: (1) the operation and management of the Bureau of Reclamation's Klamath Water Project and Central Valley Project (e.g., Trinity River dams); (2) management of federal lands in the Basin, including five national wildlife refuges, several national forests, and public lands; and (3) implementation of federal laws, such as the Endangered Species Act (ESA), Clean Water Act (CWA), and National Environmental Policy Act (NEPA). Conflict was sparked in April of 2001 when the Bureau of Reclamation, which has supplied water to farms in the Upper Basin for nearly 100 years, announced that "no water [would] be available" for farms normally receiving water from the Upper Klamath Lake to avoid jeopardizing the existence of three fish species listed as endangered or threatened under the ESA. While some water was subsequently made available to some farmers from other sources (e.g., wells and other Bureau sources), many farmers faced serious hardships. During Reclamation's operations in September of 2002, warm water temperatures and atypically low flows in the lower Klamath contributed to the death of at least 33,000 adult salmonids. This die-off damaged fish stocks and the tribes, commercial fishermen, and recreational anglers that catch Klamath fish. There have been many studies, Biological Opinions, and operating plans over recent years, all of which have been controversial. The events of 2001 and 2002 prompted renewed efforts to resolve water conflicts in the Klamath Basin. Congress has responded to the controversy in a number of ways, including holding oversight hearings and appropriating funds for activities in the area. This report provides an overview of recent conflict in the Klamath Basin, with an emphasis on activities in the Upper Basin, and summarizes some of the activities taking place to improve water supply reliability and fish survival. This report will be updated as events warrant. Close

• 82. [Article] Species Diversification in Aquaculture: a Global Assessment

  Suggested Bibliographic Reference: Challenging New Frontiers in the Global Seafood Sector: Proceedings of the Eighteenth Biennial Conference of the International Institute of Fisheries Economics and Trade, ...

  Citation × Citation Citation Abstract Copy Title: Species Diversification in Aquaculture: a Global Assessment Author: Zhou, Xiaowei, Yan, Xue, Cai, Junning Year: 2016 Suggested Bibliographic Reference: Challenging New Frontiers in the Global Seafood Sector: Proceedings of the Eighteenth Biennial Conference of the International Institute of Fisheries Economics and Trade, July 11-15, 2016. Compiled by Stefani J. Evers and Ann L. Shriver. International Institute of Fisheries Economics and Trade (IIFET), Corvallis, 2016. Title: Species Diversification in Aquaculture: a Global Assessment Author: Zhou, Xiaowei, Yan, Xue, Cai, Junning Year: 2016 Suggested Bibliographic Reference: Challenging New Frontiers in the Global Seafood Sector: Proceedings of the Eighteenth Biennial Conference of the International Institute of Fisheries Economics and Trade, July 11-15, 2016. Compiled by Stefani J. Evers and Ann L. Shriver. International Institute of Fisheries Economics and Trade (IIFET), Corvallis, 2016. Close

• 83. [Article] Host species composition influences infection severity among amphibians in the absence of spillover transmission

  This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by John Wiley & Sons Ltd. The published article can be found at: http://onlinelibrary.wiley.com/jo...

  Citation × Citation Citation Abstract Copy Title: Host species composition influences infection severity among amphibians in the absence of spillover transmission Author: Han, Barbara A., Storfer, Andrew, Blaustein, Andrew R., Searle, Catherine L., Kerby, Jacob L. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by John Wiley & Sons Ltd. The published article can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%292045-7758 Title: Host species composition influences infection severity among amphibians in the absence of spillover transmission Author: Han, Barbara A., Storfer, Andrew, Blaustein, Andrew R., Searle, Catherine L., Kerby, Jacob L. This is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by John Wiley & Sons Ltd. The published article can be found at: http://onlinelibrary.wiley.com/journal/10.1002/%28ISSN%292045-7758 Close

• 84. [Article] Evaluating the public health risks of methylmercury exposure and benefits from omega-3 fatty acids and selenium from fish consumption

  Although fish are a nutritious food source, they also are the main source of methylmercury exposure in U.S. populations. This research examined the risks from methylmercury and benefits from omega-3 fatty ...

  Citation × Citation Citation Abstract Copy Title: Evaluating the public health risks of methylmercury exposure and benefits from omega-3 fatty acids and selenium from fish consumption Author: Cusack, Leanne K. Although fish are a nutritious food source, they also are the main source of methylmercury exposure in U.S. populations. This research examined the risks from methylmercury and benefits from omega-3 fatty acids and selenium from fish consumption. The first study provided the first region-specific quantitative risk/benefit analysis for nine commonly consumed freshwater fish species in the Columbia River Basin; which is home to many Native American Tribes and subsistence fishermen who consume large quantities of locally caught fish. (Donatuto and Harper 2008; Harper and Harris 2008)(Donatuto and Harper 2008; Harper and Harris 2008) My results showed that mountain whitefish and rainbow trout provided a net benefit for cardiovascular risk and improved infant visual response memory scores across all consumption rates in all subregions in which they were sampled. The second study examined the associations between region of residence, demographic characteristics and total blood mercury concentrations in a nationally representative sample of women of childbearing age, using the 1999-2010 NHANES database. Women who live in the Atlantic and Pacific coastal regions have the highest, and women in the Midwest have the lowest, methymercury concentrations in their blood. The third study analyzed intra-and inter-specific variability in selenium: mercury molar ratios in ten species of freshwater fish from the Columbia River Basin to determine the potential application for fish consumption guidelines. Variability in selenium:mercury molar ratios was high within the fish species regardless of fish size. This variability within fish species warrants caution in using selenium:mercury ratios in risk assessment calculations. Overall, this research demonstrates the complexities involved in crafting guidelines that consider both the risks and benefits of fish consumption. Title: Evaluating the public health risks of methylmercury exposure and benefits from omega-3 fatty acids and selenium from fish consumption Author: Cusack, Leanne K. Although fish are a nutritious food source, they also are the main source of methylmercury exposure in U.S. populations. This research examined the risks from methylmercury and benefits from omega-3 fatty acids and selenium from fish consumption. The first study provided the first region-specific quantitative risk/benefit analysis for nine commonly consumed freshwater fish species in the Columbia River Basin; which is home to many Native American Tribes and subsistence fishermen who consume large quantities of locally caught fish. (Donatuto and Harper 2008; Harper and Harris 2008)(Donatuto and Harper 2008; Harper and Harris 2008) My results showed that mountain whitefish and rainbow trout provided a net benefit for cardiovascular risk and improved infant visual response memory scores across all consumption rates in all subregions in which they were sampled. The second study examined the associations between region of residence, demographic characteristics and total blood mercury concentrations in a nationally representative sample of women of childbearing age, using the 1999-2010 NHANES database. Women who live in the Atlantic and Pacific coastal regions have the highest, and women in the Midwest have the lowest, methymercury concentrations in their blood. The third study analyzed intra-and inter-specific variability in selenium: mercury molar ratios in ten species of freshwater fish from the Columbia River Basin to determine the potential application for fish consumption guidelines. Variability in selenium:mercury molar ratios was high within the fish species regardless of fish size. This variability within fish species warrants caution in using selenium:mercury ratios in risk assessment calculations. Overall, this research demonstrates the complexities involved in crafting guidelines that consider both the risks and benefits of fish consumption. Close

• 85. [Article] Cost-efficient management of aquatic invasive species : application to New Zealand mudsnails in the Pacific Northwest

  By affecting the ecological, pecuniary and aesthetic productivity of ecosystems, invasive species (IS) increase production and management costs to business, while straining public agencies' budgets with ...

  Citation × Citation Citation Abstract Copy Title: Cost-efficient management of aquatic invasive species : application to New Zealand mudsnails in the Pacific Northwest Author: Lim, Youngah By affecting the ecological, pecuniary and aesthetic productivity of ecosystems, invasive species (IS) increase production and management costs to business, while straining public agencies' budgets with monitoring, enforcement and management efforts. Understanding invasion pathways or vectors, and identifying costs and benefits of alternative management strategies are critical to public and private decision making in agriculture, natural resource and recreation industries. This study develops an integrated spatial framework to measure IS risk and cost-efficiency of alternative IS management strategies. For a given spatial unit, the framework weighs expected damages, based on measured IS risk, against the cost of alternative management strategies, i.e. spatial cost minimization. The study then applied the spatial cost minimization framework to the case of New Zealand mudsnails, Potamopyrgus antipodarum, (NZMS) in the Pacific Northwest (PNW) using data from a variety of sources. The first stage of the integrated framework is the measurement of NZMS establishment risk, which is estimated as a combination of anthropogenic introduction risk and habitat suitability risk. Since recreational boats are a main vector to disperse NZMS, the normalized boat flows in the PNW states—Idaho, Oregon, and Washington—are used as a proxy for the anthropogenic introduction risk. An environmental niche model then revealed the relationship between environmental features and NZMS presence, i.e. habitat suitability risk. Results suggest that distance, area size, water body concentration, and accessibility are major determinants of PNW recreational boat flows. Environmental characteristics such as elevation, geologic features, precipitation in January, March, and September, as well as the minimum temperature of June, July, and August, and the maximum temperature of June, August, and October are important determinants of PNW's habitat suitability for NZMS. Potential damages arising from NZMS include anglers' utility loss, which is caused by aquatic habitat degradation due to NZMS invasion, and biofouling influence on hydroelectricity plants, drinking water treatment plants, and boats. Because NZMS economic damages and related management cost are not yet fully identified in the literature, damages and management cost of zebra mussels serve as proxies for those of NZMS. Expected damages are then derived as the product of NZMS establishment risk from the first stage and potential damages noted above. Statewide management cost information is compiled from a phone survey of PNW invasive species field managers. Statewide and local management strategies are prevention, early detection and rapid response and its follow-up (EDRR plus) and ex-post management without EDRR. Local strategies additionally include boater decontamination and fish hatchery prevention efforts. Finally, the spatial cost minimization problem evaluates expected damages against the cost of each alternative management strategy (statewide and local). Solutions to this minimization problem, i.e. cost-efficient strategies, are derived for individual spatial units in each of the three PNW states. Reflecting uncertainty in the relationship between NZMS impacts and management, the spatial cost minimization is solved under different scenarios: unconstrained, NZMS damages are a fraction of those of zebra mussels, variation in the effectiveness of statewide and local management strategies, a budget constraint, and targeted NZMS risk level constraint. Results show that statewide prevention, local boater decontamination and fish hatchery prevention are the cost-efficient strategies for managing NZMS in the Pacific Northwest in most cases. Title: Cost-efficient management of aquatic invasive species : application to New Zealand mudsnails in the Pacific Northwest Author: Lim, Youngah By affecting the ecological, pecuniary and aesthetic productivity of ecosystems, invasive species (IS) increase production and management costs to business, while straining public agencies' budgets with monitoring, enforcement and management efforts. Understanding invasion pathways or vectors, and identifying costs and benefits of alternative management strategies are critical to public and private decision making in agriculture, natural resource and recreation industries. This study develops an integrated spatial framework to measure IS risk and cost-efficiency of alternative IS management strategies. For a given spatial unit, the framework weighs expected damages, based on measured IS risk, against the cost of alternative management strategies, i.e. spatial cost minimization. The study then applied the spatial cost minimization framework to the case of New Zealand mudsnails, Potamopyrgus antipodarum, (NZMS) in the Pacific Northwest (PNW) using data from a variety of sources. The first stage of the integrated framework is the measurement of NZMS establishment risk, which is estimated as a combination of anthropogenic introduction risk and habitat suitability risk. Since recreational boats are a main vector to disperse NZMS, the normalized boat flows in the PNW states—Idaho, Oregon, and Washington—are used as a proxy for the anthropogenic introduction risk. An environmental niche model then revealed the relationship between environmental features and NZMS presence, i.e. habitat suitability risk. Results suggest that distance, area size, water body concentration, and accessibility are major determinants of PNW recreational boat flows. Environmental characteristics such as elevation, geologic features, precipitation in January, March, and September, as well as the minimum temperature of June, July, and August, and the maximum temperature of June, August, and October are important determinants of PNW's habitat suitability for NZMS. Potential damages arising from NZMS include anglers' utility loss, which is caused by aquatic habitat degradation due to NZMS invasion, and biofouling influence on hydroelectricity plants, drinking water treatment plants, and boats. Because NZMS economic damages and related management cost are not yet fully identified in the literature, damages and management cost of zebra mussels serve as proxies for those of NZMS. Expected damages are then derived as the product of NZMS establishment risk from the first stage and potential damages noted above. Statewide management cost information is compiled from a phone survey of PNW invasive species field managers. Statewide and local management strategies are prevention, early detection and rapid response and its follow-up (EDRR plus) and ex-post management without EDRR. Local strategies additionally include boater decontamination and fish hatchery prevention efforts. Finally, the spatial cost minimization problem evaluates expected damages against the cost of each alternative management strategy (statewide and local). Solutions to this minimization problem, i.e. cost-efficient strategies, are derived for individual spatial units in each of the three PNW states. Reflecting uncertainty in the relationship between NZMS impacts and management, the spatial cost minimization is solved under different scenarios: unconstrained, NZMS damages are a fraction of those of zebra mussels, variation in the effectiveness of statewide and local management strategies, a budget constraint, and targeted NZMS risk level constraint. Results show that statewide prevention, local boater decontamination and fish hatchery prevention are the cost-efficient strategies for managing NZMS in the Pacific Northwest in most cases. Close

• 86. [Article] Reefscapes of Fear: Predation Risk and Reef Hetero-Geneity Interact to Shape Herbivore Foraging Behaviour

  Predators can exert strong direct and indirect effects on ecological communities by intimidating their prey. The nature of predation risk effects is often context dependent, but in some ecosystems these ...

  Citation × Citation Citation Abstract Copy Title: Reefscapes of Fear: Predation Risk and Reef Hetero-Geneity Interact to Shape Herbivore Foraging Behaviour Author: Catano, Laura B., Rojas, Maria C., Malossi, Ryan J., Peters, Joseph R., Heathaus, Michael R., Fourquren, James W., Burkepile, Deron E. Year: 2016 Predators can exert strong direct and indirect effects on ecological communities by intimidating their prey. The nature of predation risk effects is often context dependent, but in some ecosystems these contingencies are often overlooked. Risk effects are often not uniform across landscapes or among species. Indeed, they can vary widely across gradients of habitat complexity and with different prey escape tactics. These context dependencies may be especially important for ecosystems such as coral reefs that vary widely in habitat complexity and have species-rich predator and prey communities. With field experiments using predator decoys of the black grouper (Mycteroperca bonaci), we investigated how reef complexity interacts with predation risk to affect the foraging behaviour and herbivory rates of large herbivorous fishes (e.g. parrotfishes and surgeonfishes) across four coral reefs in the Florida Keys (USA). In both high and low complexity areas of the reef, we measured how herbivory changed with increasing distance from the predator decoy to examine how herbivorous fishes reconcile the conflicting demands of avoiding predation vs. foraging within a reefscape context. We show that with increasing risk, herbivorous fishes consumed dramatically less food (ca. 90%) but fed at a faster rate when they did feed (ca. 26%). Furthermore, we show that fishes foraging closest to the predator decoy were 40% smaller than those that foraged at further distances. Thus, smaller individuals showed muted response to predation risk compared to their larger counterparts, potentially due to their decreased risk to predation or lower reproductive value (i.e. the asset protection principle). Habitat heterogeneity mediated risk effects differently for different species of herbivores, with predation risk more strongly suppressing herbivore feeding in more complex areas and for individuals at higher risk of predation. Predators appear to create a reefscape of fear that changes the size structure of herbivores towards smaller individuals, increases individual feeding rates, but suppresses overall amounts of primary producers consumed, potentially altering patterns of herbivory, an ecosystem process critical for healthy coral reefs. Title: Reefscapes of Fear: Predation Risk and Reef Hetero-Geneity Interact to Shape Herbivore Foraging Behaviour Author: Catano, Laura B., Rojas, Maria C., Malossi, Ryan J., Peters, Joseph R., Heathaus, Michael R., Fourquren, James W., Burkepile, Deron E. Year: 2016 Predators can exert strong direct and indirect effects on ecological communities by intimidating their prey. The nature of predation risk effects is often context dependent, but in some ecosystems these contingencies are often overlooked. Risk effects are often not uniform across landscapes or among species. Indeed, they can vary widely across gradients of habitat complexity and with different prey escape tactics. These context dependencies may be especially important for ecosystems such as coral reefs that vary widely in habitat complexity and have species-rich predator and prey communities. With field experiments using predator decoys of the black grouper (Mycteroperca bonaci), we investigated how reef complexity interacts with predation risk to affect the foraging behaviour and herbivory rates of large herbivorous fishes (e.g. parrotfishes and surgeonfishes) across four coral reefs in the Florida Keys (USA). In both high and low complexity areas of the reef, we measured how herbivory changed with increasing distance from the predator decoy to examine how herbivorous fishes reconcile the conflicting demands of avoiding predation vs. foraging within a reefscape context. We show that with increasing risk, herbivorous fishes consumed dramatically less food (ca. 90%) but fed at a faster rate when they did feed (ca. 26%). Furthermore, we show that fishes foraging closest to the predator decoy were 40% smaller than those that foraged at further distances. Thus, smaller individuals showed muted response to predation risk compared to their larger counterparts, potentially due to their decreased risk to predation or lower reproductive value (i.e. the asset protection principle). Habitat heterogeneity mediated risk effects differently for different species of herbivores, with predation risk more strongly suppressing herbivore feeding in more complex areas and for individuals at higher risk of predation. Predators appear to create a reefscape of fear that changes the size structure of herbivores towards smaller individuals, increases individual feeding rates, but suppresses overall amounts of primary producers consumed, potentially altering patterns of herbivory, an ecosystem process critical for healthy coral reefs. Close

• 87. [Article] Improving ecological risk assessment of pesticides for nontarget terrestrial vertebrates

  The Quotient Method (QM) is used by the United States Environmental Protection Agency (USEPA) in ecological risk assessments of pesticides for nontarget organisms. The QM requires several assumptions regarding ...

  Citation × Citation Citation Abstract Copy Title: Improving ecological risk assessment of pesticides for nontarget terrestrial vertebrates Author: Wang, Guiming The Quotient Method (QM) is used by the United States Environmental Protection Agency (USEPA) in ecological risk assessments of pesticides for nontarget organisms. The QM requires several assumptions regarding exposure and hazards of pesticides to wildlife; several of these assumptions have not been tested. During 1997-99, I conducted three experiments using the gray-tailed vole (Microtus canicaudus) as a model species to test three assumptions of the QM. The experiments were conducted in 24 0.2-ha fenced vole-proof enclosures. In Experiment 1, I tracked voles using radio-telemetry and found that animals did not move from contaminated to uncontaminated habitat to avoid exposure to a pesticide, thus supporting one assumption of the QM. In Experiment 2, I studied demographic responses of gray-tailed voles and northern bobwhite quail (Colinus virginianus) to liquid and granular formulations of diazinon. The results of Experiment 2 indicated that quail were more susceptible to granular diazinon than to liquid diazinon because of direct consumption of diazinon granules. Neither formulation of diazinon at 0.55 or 1.55 kg AI/ha adversely affected vole demography. In Experiment 3, I used sprinklers to simulate a 0.25-cm rainfall to test the assumption that the expected environmental concentration (EEC) of a pesticide is estimated immediately after application, and that rainfall does not modify the risk of pesticides to animals. The 0.25-cm rainfall may have reduced the risk of voles to Guthion® 2S either by improving the dry season habitat or by washing more pesticide residues down to the soil and reducing exposure of the animals. This experiment did not support the assumption of the QM that weather would not affect the EEC of pesticides. Last, I used a Ricker model incorporating demographic stochasticity to simulate the 1998 and 1999 vole populations and a single pesticide application at different population sizes. The simulations demonstrate that demographic stochasticity could cause uncertainties in predictions of significant effects of pesticide on voles, especially for small populations. These simulations suggest that ecological risk assessments of pesticides to nontarget wildlife should consider demographic characteristics of wildlife species to minimize the uncertainty of predictions. Title: Improving ecological risk assessment of pesticides for nontarget terrestrial vertebrates Author: Wang, Guiming The Quotient Method (QM) is used by the United States Environmental Protection Agency (USEPA) in ecological risk assessments of pesticides for nontarget organisms. The QM requires several assumptions regarding exposure and hazards of pesticides to wildlife; several of these assumptions have not been tested. During 1997-99, I conducted three experiments using the gray-tailed vole (Microtus canicaudus) as a model species to test three assumptions of the QM. The experiments were conducted in 24 0.2-ha fenced vole-proof enclosures. In Experiment 1, I tracked voles using radio-telemetry and found that animals did not move from contaminated to uncontaminated habitat to avoid exposure to a pesticide, thus supporting one assumption of the QM. In Experiment 2, I studied demographic responses of gray-tailed voles and northern bobwhite quail (Colinus virginianus) to liquid and granular formulations of diazinon. The results of Experiment 2 indicated that quail were more susceptible to granular diazinon than to liquid diazinon because of direct consumption of diazinon granules. Neither formulation of diazinon at 0.55 or 1.55 kg AI/ha adversely affected vole demography. In Experiment 3, I used sprinklers to simulate a 0.25-cm rainfall to test the assumption that the expected environmental concentration (EEC) of a pesticide is estimated immediately after application, and that rainfall does not modify the risk of pesticides to animals. The 0.25-cm rainfall may have reduced the risk of voles to Guthion® 2S either by improving the dry season habitat or by washing more pesticide residues down to the soil and reducing exposure of the animals. This experiment did not support the assumption of the QM that weather would not affect the EEC of pesticides. Last, I used a Ricker model incorporating demographic stochasticity to simulate the 1998 and 1999 vole populations and a single pesticide application at different population sizes. The simulations demonstrate that demographic stochasticity could cause uncertainties in predictions of significant effects of pesticide on voles, especially for small populations. These simulations suggest that ecological risk assessments of pesticides to nontarget wildlife should consider demographic characteristics of wildlife species to minimize the uncertainty of predictions. Close

• 88. [Article] Risk assessment : introduction and establishment of Myxobolus cerebralis in the Deschutes River Basin, Oregon, USA

  A plan for the reestablishment of anadromous salmonid stocks into waters above the Pelton Round Butte Hydroelectric Project (PRB) located on the Deschutes River, Oregon has been under development since ...

  Citation × Citation Citation Abstract Copy Title: Risk assessment : introduction and establishment of Myxobolus cerebralis in the Deschutes River Basin, Oregon, USA Author: Zielinski, Christopher A plan for the reestablishment of anadromous salmonid stocks into waters above the Pelton Round Butte Hydroelectric Project (PRB) located on the Deschutes River, Oregon has been under development since 1996. The PRB complex, starting at river kilometer (Rkm) 103, blocks the further upstream migration of anadromous salmonids into upper river basin waters. Part of the process for evaluating the passage plan was the development of a Fish Health Management Program. The program is, in part, designed to minimize and communicate the magnitude of risk associated with passing serious fish pathogens upstream of the PRB until evaluation of the fish passage effort confirms that the reestablishment of anadromous fish species can be successful. With the goal of minimizing the risk of passing serious fish pathogens along with evaluating the magnitude of risk, several potential pathogens of concern were identified. At the forefront of concern is the fish pathogen Myxobolus cerebralis which is responsible for whirling disease in salmonids. Annual, or at least periodic, introduction of M. cerebralis into the lower DRB has occurred since at least 1984 as a result of infected stray adult salmonids spawning and dying there. These are primarily hatchery summer steelhead (Oncorhynchus mykiss), and to a lesser extent spring Chinook salmon (O. tshawytscha), from the Snake River system. Because of its' potential to cause significant mortality, the risk associated with M. cerebralis establishment in the DRB needed to be addressed. The risk of the parasite being transmitted and established upstream of the PRB with the renewal of fish passage at the PRB, and the potential for M. cerebralis to affect survival of reintroduced anadromous fish species required investigation. To evaluate these potential risks, we conducted multi-year studies (1998-2007) that informed a risk-assessment model. Tailored specifically for M. cerebralis, this model was used to identify key characteristics that will influence pathways of M. cerebralis introduction, the potential for establishment, and the consequences of establishment. The three steps involved in the risk assessment model are the release, exposure and consequence assessments. Using this model we evaluated the probability of introduction and establishment of M. cerebralis in the lower Deschutes River Basin (DRB) as well as in waters above the PRB with future passage of anadromous fish. The current study gives evidence that M. cerebralis is established in the lower DRB. The current study also gives evidence not all areas of the DRB can be classified as having the same likelihood for establishment and the potential impact the parasite poses will not be identical from one location to another. It is clear, however, that M. cerebralis could become established above the PRB if infected fish carry the myxospore into these waters. Title: Risk assessment : introduction and establishment of Myxobolus cerebralis in the Deschutes River Basin, Oregon, USA Author: Zielinski, Christopher A plan for the reestablishment of anadromous salmonid stocks into waters above the Pelton Round Butte Hydroelectric Project (PRB) located on the Deschutes River, Oregon has been under development since 1996. The PRB complex, starting at river kilometer (Rkm) 103, blocks the further upstream migration of anadromous salmonids into upper river basin waters. Part of the process for evaluating the passage plan was the development of a Fish Health Management Program. The program is, in part, designed to minimize and communicate the magnitude of risk associated with passing serious fish pathogens upstream of the PRB until evaluation of the fish passage effort confirms that the reestablishment of anadromous fish species can be successful. With the goal of minimizing the risk of passing serious fish pathogens along with evaluating the magnitude of risk, several potential pathogens of concern were identified. At the forefront of concern is the fish pathogen Myxobolus cerebralis which is responsible for whirling disease in salmonids. Annual, or at least periodic, introduction of M. cerebralis into the lower DRB has occurred since at least 1984 as a result of infected stray adult salmonids spawning and dying there. These are primarily hatchery summer steelhead (Oncorhynchus mykiss), and to a lesser extent spring Chinook salmon (O. tshawytscha), from the Snake River system. Because of its' potential to cause significant mortality, the risk associated with M. cerebralis establishment in the DRB needed to be addressed. The risk of the parasite being transmitted and established upstream of the PRB with the renewal of fish passage at the PRB, and the potential for M. cerebralis to affect survival of reintroduced anadromous fish species required investigation. To evaluate these potential risks, we conducted multi-year studies (1998-2007) that informed a risk-assessment model. Tailored specifically for M. cerebralis, this model was used to identify key characteristics that will influence pathways of M. cerebralis introduction, the potential for establishment, and the consequences of establishment. The three steps involved in the risk assessment model are the release, exposure and consequence assessments. Using this model we evaluated the probability of introduction and establishment of M. cerebralis in the lower Deschutes River Basin (DRB) as well as in waters above the PRB with future passage of anadromous fish. The current study gives evidence that M. cerebralis is established in the lower DRB. The current study also gives evidence not all areas of the DRB can be classified as having the same likelihood for establishment and the potential impact the parasite poses will not be identical from one location to another. It is clear, however, that M. cerebralis could become established above the PRB if infected fish carry the myxospore into these waters. Close

• 89. [Article] Assessment of chlorinated hydrocarbons and trace metal contamination of Moroccan marine species

  Citation × Citation Citation Abstract Copy Title: Assessment of chlorinated hydrocarbons and trace metal contamination of Moroccan marine species Author: El Hraiki, Abdelaziz Title: Assessment of chlorinated hydrocarbons and trace metal contamination of Moroccan marine species Author: El Hraiki, Abdelaziz Close

• 90. [Article] Invasive Species Management Plan for Oswego Lake

  This Invasive Species Management Plan defines an overarching strategy for the Lake Oswego Corporation (LOC) to mitigate threats from invasive species to Oswego Lake. Invasive species pose a direct risk ...

  Citation × Citation Citation Abstract Copy Title: Invasive Species Management Plan for Oswego Lake Author: Warren, Daniel Year: 2009 This Invasive Species Management Plan defines an overarching strategy for the Lake Oswego Corporation (LOC) to mitigate threats from invasive species to Oswego Lake. Invasive species pose a direct risk to recreational and aesthetic uses of the lake, critical LOC infrastructure, and ecological communities within the lake. The Plan is particularly concerned with two bivalve mollusks in the genus Dreissena: the zebra mussel (Dreissena polymorpha) and the quagga mussel (Dreissena bugensis). These mussels grow in dense colonies that damage watercraft and underwater structures as well as displace native species. A recent scientific report found that an intense infestation of mussels in Oswego Lake is unlikely due to the water chemistry, but a low to moderate level of infestation is possible. Any level of infestation could be very serious and warrants proactive preventative measures and response plans should an invasion occur. In addition to the harmful mussels, this Plan identifies preventative and response measures for other species such as hydrilla (Hydrilla verticillata) that have the potential to harm Oswego Lake. Strategies outlined in this Plan are as follows: • Identification and prioritization of likely potential invasive species • Identification of vectors of establishment •Prevention strategies • Development of monitoring plans • Rapid response action plans and control measures if an invasion is detected Prevention is the top management priority for all invasive species as the cost and difficulty of controlling or eradicating an invasion increase significantly as an invasion spreads. This includes active measures to exclude species as well as the ongoing education and involvement of community members. Effective monitoring and rapid response action plans are the next priority to detect and eradicate an exotic species before it establishes and spreads. The integration of these strategies will help the LOC prevent significant deleterious effects from invasive species in Oswego Lake so that the basic operations of the LOC are facilitated and recreational and aesthetic opportunities are preserved. Title: Invasive Species Management Plan for Oswego Lake Author: Warren, Daniel Year: 2009 This Invasive Species Management Plan defines an overarching strategy for the Lake Oswego Corporation (LOC) to mitigate threats from invasive species to Oswego Lake. Invasive species pose a direct risk to recreational and aesthetic uses of the lake, critical LOC infrastructure, and ecological communities within the lake. The Plan is particularly concerned with two bivalve mollusks in the genus Dreissena: the zebra mussel (Dreissena polymorpha) and the quagga mussel (Dreissena bugensis). These mussels grow in dense colonies that damage watercraft and underwater structures as well as displace native species. A recent scientific report found that an intense infestation of mussels in Oswego Lake is unlikely due to the water chemistry, but a low to moderate level of infestation is possible. Any level of infestation could be very serious and warrants proactive preventative measures and response plans should an invasion occur. In addition to the harmful mussels, this Plan identifies preventative and response measures for other species such as hydrilla (Hydrilla verticillata) that have the potential to harm Oswego Lake. Strategies outlined in this Plan are as follows: • Identification and prioritization of likely potential invasive species • Identification of vectors of establishment •Prevention strategies • Development of monitoring plans • Rapid response action plans and control measures if an invasion is detected Prevention is the top management priority for all invasive species as the cost and difficulty of controlling or eradicating an invasion increase significantly as an invasion spreads. This includes active measures to exclude species as well as the ongoing education and involvement of community members. Effective monitoring and rapid response action plans are the next priority to detect and eradicate an exotic species before it establishes and spreads. The integration of these strategies will help the LOC prevent significant deleterious effects from invasive species in Oswego Lake so that the basic operations of the LOC are facilitated and recreational and aesthetic opportunities are preserved. Close