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• 1. [Article] Cascades Island Lamprey Passage Structure: Evaluating Passage and Migration Following Structure Modifications

  Pacific lamprey (Entosphenus tridentatus), an endemic species to the Columbia River Basin, U.S.A, has experienced staggering decreases in returns to spawning territories in recent decades. As lamprey are ...

  Citation × Citation Citation Abstract Copy Title: Cascades Island Lamprey Passage Structure: Evaluating Passage and Migration Following Structure Modifications Author: Lopez-Johnston, Siena Marie Year: 2014 Pacific lamprey (Entosphenus tridentatus), an endemic species to the Columbia River Basin, U.S.A, has experienced staggering decreases in returns to spawning territories in recent decades. As lamprey are threatened severely by a lack of passage at mainstem dams, lamprey specific passage structures have been designed and constructed to address the problem. The Cascades Island Lamprey Passage Structure (LPS) at Bonneville Dam is the longest and steepest structure of its type, following the addition of an exit pipe which allows lampreys to travel from the tailrace of the dam to the forebay. The intent of this study was to assess lamprey use of the structure and whether the structure hinders lamprey migration to subsequent dams. The study was carried out during the 2013 migration season. The study used three different treatment groups of lampreys released on five dates spanning the migration season (n=75 lamprey). Two of these groups (n=50), with different tagging methods, were released directly into the LPS to assess passage success, travel time, and tagging effect. The third group (n=25) was released into the forebay to test whether the structure impedes migration upstream. Fish were monitored via receiver arrays on the LPS and at dams on the river system. Overall passage efficiency was 74% (37 of 50 used the CI LPS successfully). Mean travel time to navigate the structure was 12 h. Fish size had no significant effect on travel time in the LPS. Water temperature had a significant effect on travel time in the LPS. There was no statistically significant effect of tagging on passage efficiency or travel time. The groups that used the LPS performed slightly better migrating upstream to the next dam than the group that bypassed the structure, but the difference was not significant. The groups that used the LPS traveled to more subsequent dams upstream than did the group that bypassed the LPS. It can be concluded that lamprey passed the structure successfully. Temperature (proxy for seasonality) had an effect on travel time in the LPS; however fish size and tagging had no effect. The LPS does not affect the ability of migrating lampreys to continue migration to subsequent dams. Such findings have important implications for management of lamprey in the region. Title: Cascades Island Lamprey Passage Structure: Evaluating Passage and Migration Following Structure Modifications Author: Lopez-Johnston, Siena Marie Year: 2014 Pacific lamprey (Entosphenus tridentatus), an endemic species to the Columbia River Basin, U.S.A, has experienced staggering decreases in returns to spawning territories in recent decades. As lamprey are threatened severely by a lack of passage at mainstem dams, lamprey specific passage structures have been designed and constructed to address the problem. The Cascades Island Lamprey Passage Structure (LPS) at Bonneville Dam is the longest and steepest structure of its type, following the addition of an exit pipe which allows lampreys to travel from the tailrace of the dam to the forebay. The intent of this study was to assess lamprey use of the structure and whether the structure hinders lamprey migration to subsequent dams. The study was carried out during the 2013 migration season. The study used three different treatment groups of lampreys released on five dates spanning the migration season (n=75 lamprey). Two of these groups (n=50), with different tagging methods, were released directly into the LPS to assess passage success, travel time, and tagging effect. The third group (n=25) was released into the forebay to test whether the structure impedes migration upstream. Fish were monitored via receiver arrays on the LPS and at dams on the river system. Overall passage efficiency was 74% (37 of 50 used the CI LPS successfully). Mean travel time to navigate the structure was 12 h. Fish size had no significant effect on travel time in the LPS. Water temperature had a significant effect on travel time in the LPS. There was no statistically significant effect of tagging on passage efficiency or travel time. The groups that used the LPS performed slightly better migrating upstream to the next dam than the group that bypassed the structure, but the difference was not significant. The groups that used the LPS traveled to more subsequent dams upstream than did the group that bypassed the LPS. It can be concluded that lamprey passed the structure successfully. Temperature (proxy for seasonality) had an effect on travel time in the LPS; however fish size and tagging had no effect. The LPS does not affect the ability of migrating lampreys to continue migration to subsequent dams. Such findings have important implications for management of lamprey in the region. Close

• 2. [Article] Since Time Immemorial: The Decline of Columbia River Basin Salmon

  Since Time Immemorial: The Decline of Columbia River Basin Salmon studies the near extinction of what has been historically the world’s largest salmon population. By examining the issue systemically, my ...

  Citation × Citation Citation Abstract Copy Title: Since Time Immemorial: The Decline of Columbia River Basin Salmon Author: Levin, Samuel J Year: 2016 Since Time Immemorial: The Decline of Columbia River Basin Salmon studies the near extinction of what has been historically the world’s largest salmon population. By examining the issue systemically, my paper reveals that the environmental misjudgments that have brought the salmon so near extinction are not isolated, but rather are the product of cultural trends. A study of these misjudgments reveals a culture within the Columbia Basin that has, since the mid-19th century, sought expansion for expansion’s sake and valued short-term wealth over long-term sustainability. My paper illustrates how his philosophy has guided and continues to guide Columbia Basin fisheries management to neglect not just environmental and Native American considerations, but pragmatic ones as well. Title: Since Time Immemorial: The Decline of Columbia River Basin Salmon Author: Levin, Samuel J Year: 2016 Since Time Immemorial: The Decline of Columbia River Basin Salmon studies the near extinction of what has been historically the world’s largest salmon population. By examining the issue systemically, my paper reveals that the environmental misjudgments that have brought the salmon so near extinction are not isolated, but rather are the product of cultural trends. A study of these misjudgments reveals a culture within the Columbia Basin that has, since the mid-19th century, sought expansion for expansion’s sake and valued short-term wealth over long-term sustainability. My paper illustrates how his philosophy has guided and continues to guide Columbia Basin fisheries management to neglect not just environmental and Native American considerations, but pragmatic ones as well. Close

• 3. [Article] Scientifically Defensible Fish Conservation and Recovery Plans: Addressing Diffuse Threats and Developing Rigorous Adaptive Management Plans

  We discuss the importance of addressing diffuse threats to long-term species and habitat viability in fish conservation and recovery planning. In the Pacific Northwest, USA, salmonid management plans have ...

  Citation × Citation Citation Abstract Copy Title: Scientifically Defensible Fish Conservation and Recovery Plans: Addressing Diffuse Threats and Developing Rigorous Adaptive Management Plans Author: Maas-Hebner, Kathleen G., Schreck, Carl B., Hughes, Robert M., Yeakley, J. Alan, Molina, Nancy Year: 2016 We discuss the importance of addressing diffuse threats to long-term species and habitat viability in fish conservation and recovery planning. In the Pacific Northwest, USA, salmonid management plans have typically focused on degraded freshwater habitat, dams, fish passage, harvest rates, and hatchery releases. However, such plans inadequately address threats related to human population and economic growth, intra- and interspecific competition, and changes in climate, ocean, and estuarine conditions. Based on reviews conducted on eight conservation and/or recovery plans, we found that though threats resulting from such changes are difficult to model and/or predict, they are especially important for wide-ranging diadromous species. Adaptive management is also a critical but often inadequately constructed component of those plans. Adaptive management should be designed to respond to evolving knowledge about the fish and their supporting ecosystems; if done properly, it should help improve conservation efforts by decreasing uncertainty regarding known and diffuse threats. We conclude with a general call for environmental managers and planners to reinvigorate the adaptive management process in future management plans, including more explicitly identifying critical uncertainties, implementing monitoring programs to reduce those uncertainties, and explicitly stating what management actions will occur when pre-identified trigger points are reached. Title: Scientifically Defensible Fish Conservation and Recovery Plans: Addressing Diffuse Threats and Developing Rigorous Adaptive Management Plans Author: Maas-Hebner, Kathleen G., Schreck, Carl B., Hughes, Robert M., Yeakley, J. Alan, Molina, Nancy Year: 2016 We discuss the importance of addressing diffuse threats to long-term species and habitat viability in fish conservation and recovery planning. In the Pacific Northwest, USA, salmonid management plans have typically focused on degraded freshwater habitat, dams, fish passage, harvest rates, and hatchery releases. However, such plans inadequately address threats related to human population and economic growth, intra- and interspecific competition, and changes in climate, ocean, and estuarine conditions. Based on reviews conducted on eight conservation and/or recovery plans, we found that though threats resulting from such changes are difficult to model and/or predict, they are especially important for wide-ranging diadromous species. Adaptive management is also a critical but often inadequately constructed component of those plans. Adaptive management should be designed to respond to evolving knowledge about the fish and their supporting ecosystems; if done properly, it should help improve conservation efforts by decreasing uncertainty regarding known and diffuse threats. We conclude with a general call for environmental managers and planners to reinvigorate the adaptive management process in future management plans, including more explicitly identifying critical uncertainties, implementing monitoring programs to reduce those uncertainties, and explicitly stating what management actions will occur when pre-identified trigger points are reached. Close