Location
Agriculture Production Theater, Oregon State University
Start Date
25-6-2013 11:00 AM
End Date
25-6-2013 11:20 AM
Description
Fishways designed for salmonids often restrict passage by non-salmonids and effective tools are needed both to identify passage problems for non-salmonid species and to inform remediation planning. In a Pacific lamprey (Entosphenus tridentatus) case study, we developed a series of fishway passage bottleneck metrics and models of potential benefits of fishway improvements at Bonneville Dam on the Columbia River. Bonneville Dam is a large, multi-fishway hydroelectric project that has features similar to many salmonid-style fishways in the Pacific Northwest. Overall, 49% of tagged lamprey that entered Bonneville fishways failed to pass the dam, a much lower rate of success than has been recorded for adult Pacific salmonids. Models accounting for repeated attempts by individual Pacific lamprey indicated successful passage strongly depended on attempted passage route. Time of fishway entry, water temperature, and lamprey body size were also influential. Most failed passage attempts terminated in lower fishway segments and occurred during relatively cool, high-discharge conditions. Multinomial models showed extensive seasonal shifts in bottleneck locations associated with fluctuating environmental conditions. Our integration of spatially-intensive monitoring with quantitative analytical techniques was critical to understanding the complex relationships between fishway features, environmental variation and Pacific lamprey migration behavior. The subsequent benefits models identified several priority sites where structural or operational modifications could provide the highest relative improvements in lamprey passage. Managers are currently weighing the costs of specific improvements versus potential escapement benefits. The broader research framework and analytical tools we used can be applied to a wide range of fish passage assessments.
Concurrent Sessions B: Lamprey Passage - Fishway Passage Bottlenecks And Prioritization Planning: A Pacific Lamprey Case Study
Agriculture Production Theater, Oregon State University
Fishways designed for salmonids often restrict passage by non-salmonids and effective tools are needed both to identify passage problems for non-salmonid species and to inform remediation planning. In a Pacific lamprey (Entosphenus tridentatus) case study, we developed a series of fishway passage bottleneck metrics and models of potential benefits of fishway improvements at Bonneville Dam on the Columbia River. Bonneville Dam is a large, multi-fishway hydroelectric project that has features similar to many salmonid-style fishways in the Pacific Northwest. Overall, 49% of tagged lamprey that entered Bonneville fishways failed to pass the dam, a much lower rate of success than has been recorded for adult Pacific salmonids. Models accounting for repeated attempts by individual Pacific lamprey indicated successful passage strongly depended on attempted passage route. Time of fishway entry, water temperature, and lamprey body size were also influential. Most failed passage attempts terminated in lower fishway segments and occurred during relatively cool, high-discharge conditions. Multinomial models showed extensive seasonal shifts in bottleneck locations associated with fluctuating environmental conditions. Our integration of spatially-intensive monitoring with quantitative analytical techniques was critical to understanding the complex relationships between fishway features, environmental variation and Pacific lamprey migration behavior. The subsequent benefits models identified several priority sites where structural or operational modifications could provide the highest relative improvements in lamprey passage. Managers are currently weighing the costs of specific improvements versus potential escapement benefits. The broader research framework and analytical tools we used can be applied to a wide range of fish passage assessments.
Comments
Matthew Keeferhas studied anadromous fish migration in the Columbia, Snake,and Willamette River basins for 16 years. Focal research areas have included adult salmon, steelhead, and Pacific lamprey behavior at hydroelectric dams and the effects of water temperature and climate on fish migration behaviors and survival.