Science & Data

Alaska Fisheries Science Center Salmon Bycatch Report

Alaska Fisheries Science Center Salmon Bycatch Report

Alaska Fisheries Science Center Salmon Bycatch Report

The Pacific Coastal Salmon Recovery Fund (PCSRF) database serves as a project and performance metrics database and stores salmon and steelhead-related project reports from grantees located in Alaska, Washington, Idaho, Oregon, and California.

Tracks the implementation of recovery actions from Endangered Species Act (ESA) recovery plans.

Although decreasing length at maturity has been observed in some Alaska salmon populations, the generality of this trend is poorly understood. This study was undertaken to determine whether this pattern holds for multiple species of salmon from a small watershed in Southeast Alaska (Auke Creek), and if so, what abiotic and biotic factors are contributing to this phenomenon.

Pelagic fish and jellyfish were sampled using a trawl net towed in the upper 20 m of the eastern Bering Sea during the Alaska Fisheries Science Centers’ Bering Arctic Subarctic Integrated Surveys (BASIS) during late summer, 2002–2016. Stations were approximately 30 nautical miles apart and a trawl was towed for approximately 30 minutes. Area swept was estimated from horizontal net opening and distance towed.

A radio telemetry study was conducted on Yukon River Chinook salmon during 2002–2004 to provide information on migration patterns.

This annual survey, conducted by the Southeast Coastal Monitoring (SECM) project, marks 20 consecutive years of systematically monitoring how juvenile salmon utilize marine ecosystems during a period of climate change.

Pacific salmon (Oncorhynchus spp.) are prohibited species in the federally managed Bering Sea groundfish fisheries, which are subject to complex management rules (NPMFC 2017a) that are in part designed to reduce prohibited species catch, hereafter referred to as “bycatch”. It is important to understand the stock composition of Pacific salmon caught in these fisheries, which take place in areas that are known feeding habitat for multiple brood years of Chinook salmon (Oncorhynchus tshawytscha) from many different localities in North America and Asia (Myers et al. 2007, Davis et al. 2009). Chinook salmon are economically valuable and highly prized in commercial, subsistence, and sport fisheries. Determining the geographic origin of salmon caught in federally managed fisheries is essential to understanding the effects that fishing has on Chinook salmon stocks, especially those with conservation concerns (NPFMC 2017a). This report provides genetic stock identification results for the Chinook salmon bycatch samples collected from the U.S. Bering Sea walleye pollock (Gadus chalcogrammus) trawl fishery. National Marine Fisheries Service (NMFS) geographical statistical areas (NMFS area) associated with the Bering Sea groundfish fishery (NMFS areas 509-524) and Alaska Department of Fish and Game (ADF&G) statistical areas1 are shown in Figure 1 and are used later in the report to describe the spatial distribution of the Chinook salmon bycatch and genetic samples.