Location-specific consequences of beach seine and gillnet capture on upriver-migrating sockeye salmon migration behavior and fate

Fish released after capture, or fish interacting with gear but escaping, sometimes experience fishing-related incidental mortality (FRIM). For adult Pacific salmon migrations, knowing the magnitude of FRIM is important to accurately estimate escapement, and the total impact of a specific fishery. To determine how multiple gear types are associated with FRIM at different levels of maturity, we captured sockeye salmon (Oncorhynchus nerka) by both gillnet and beach seine at three locations along their migration route (10, 26, and 72% of a 500 km freshwater migration) and determined their migratory success using biotelemetry. FRIM was higher for fish captured by gillnet except at the location closest to spawning grounds. In addition, salmon captured by gillnet at the lower river locations temporarily delayed migration, potentially indicating a requirement for lengthier recovery time compared to beach-seined fish. These results provide the first empirical and parallel comparison of these two common in-river fishing methods for salmon, revealing clear differences in FRIM between the two fishing methods in lower river fisheries and the importance of maturity.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author