Gulf of Alaska | Fishes and Fish Habitats
Improving rockfish assessments via cooperative data collection in the Gulf of Alaska Presenter: Madison Hall , madison.hall@noaa.gov, Alaska Pacific University, NOAA
Mark Zimmermann , mark.zimmermann@noaa.gov, NOAA Brad Harris , bharris@alaskapacific.edu, Alaska Pacific University Pete Hulson , pete.hulson@noaa.gov, NOAA Julie Bonney , jbonney@alaskagroundfish.org, Alaska Groundfish Databank John Gauvin , gauvin@seanet.com, Alaska Seafood Cooperative Stan Kotwicki , stan.kotwicki@noaa.gov, NOAA
In Alaska, groundfish bottom trawl surveys conducted by the National Marine Fisheries Service (NMFS) use standardized fishing gear that is unable to sample in hard, rough, and rocky areas. Over the lifetime of the Gulf of Alaska (GOA) bottom trawl survey, many rough and rocky habitat stations have been marked as “untrawlable” and eliminated from future sampling plans. For fish species that prefer rocky habitats, biomass estimates from the standardized surveys may be imprecise and/or negatively biased due to the exclusion of these areas. Even though NMFS is unable to sample in “untrawlable” habitats, several species that inhabit rocky habitat types are successfully targeted by commercial fisheries. Specifically, Pacific Ocean perch ( Sebastes alutus ), northern ( S. polyspinis ) and dusky ( S. variabilis ) rockfish are commercially important to the Amendment 80 catcher-processor fleet and the Kodiak-based catcher vessel trawl fleet in the Gulf of Alaska. Our project, the Science-Industry Rockfish Research Collaboration in Alaska (SIRRCA), has been working with the GOA fishing industry to build a cooperative survey that uses industry vessels and gear to sample in areas that are “untrawlable” to the NMFS bottom trawl survey. During the pilot phase of our project we have collected data on two catcher/processor vessels and one catcher vessel, successfully sampling 34 NMFS survey stations. SIRRCA project tows focus on either calibrating catch per unit effort (CPUE) between vessels, or gathering rockfish biomass information at “untrawlable” survey stations. We plan to use SIRRCA data as a supplemental source of population abundance data to inform, and perhaps improve, official GOA rockfish stock assessments. Additionally, we are using simulations to explore the impacts of omitting important habitats on rockfish biomass estimate bias and CV. We believe SIRRCA’s cooperative science model holds great promise for fisheries science, and we hope that sharing our cooperative model will help the development of other cooperative fishery projects both nationally and globally.
Alaska Marine Science Symposium 2023 14
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