in the lower Columbia River (Vander Haegen et al. ![]() ![]() Although mortality rates differ between species and fisheries across the West Coast, Chinook Salmon Oncorhynchus tshawytscha bycatch mortality from conventional gill nets ranges from 49% to 43%. However, bycatch mortality and mixed-stock harvest can impede recovery efforts of ESA-listed stocks in lacking fishing gears that can selectively harvest targeted stocks (such as hatchery-origin fish) while leaving non-targeted fish (such as wild fish) unharmed (Wright 1993 Flagg et al. 2011 Lichatowich 2013), while minimizing mortality to wild stocks mixed within regional fisheries (Canada DFO 2005 WFWC 2009 ODFW 2013). and Canadian) agencies manage harvest to maximize catch of hatchery-origin fish-attempting to address the genetic and ecological problems associated with escapement of hatchery fish (Naish et al. By enhancing fisheries through hatchery production, resource managers increase mixed-stock fishing effort and bycatch mortality to threatened wild stocks that co-mingle with hatchery stocks during ocean rearing and the spawning migration. The effect of harvest on wild salmonids is frequently compounded by hatchery production (National Research Council 1996 Lichatowich et al. Despite many efforts to recover wild salmonids, production hatchery programs continue throughout the region in order to enhance short-term harvest opportunities in commercial, recreational, and tribal fisheries (HSRG 2014 Gayeski et al. Endangered Species Act (ESA Nehlsen et al. Europeans extirpated various wild salmonid populations shortly after their arrival to the region, and many remaining salmonid population groups are now listed for protection under the U.S. Pacific Northwest have declined dramatically from the cumulative effects of harvest, habitat loss, dams, and hatchery production (Lichatowich 1999). Since the late 1800s, wild salmonids of the U.S. Photo credit: Aaron Jorgenson INTRODUCTION mykiss to 0.995 ( = 0.078) for Chinook Salmon, supporting the potential application of traps for stock-selective commercial harvest. The postrelease survival effect over a 400-km migration ranged from 0.944 ( = 0.046) for steelhead O. ![]() During the study, 7,129 salmonids were captured. kisutch while reducing bycatch mortality rates relative to conventional commercial fishing gears. Results demonstrate that the trap effectively targeted commercially viable quantities of hatchery-origin Chinook Salmon Oncorhynchus tshawytscha and Coho Salmon O. Postrelease survival from the trap was estimated through a paired release–recapture study. A modified fish trap was constructed and operated in 2017, from August through September, with the goal of minimizing entanglement, air exposure, crowding, and handling of all captured fishes. To address the problem, a postrelease survival study was conducted in the Columbia River to evaluate the potential of an experimental salmon trap for stock-selective commercial harvest. Conventional harvest techniques used in mixed-stock commercial salmon fisheries frequently result in bycatch mortality, thereby impeding salmonid recovery and constraining fishing opportunities in the U.S.
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