2013 Assessment of the Demersal Shelf Rockfish Stock Complex in the Southeast Outside District of the Gulf of the Alaska

April 23, 2013

The demersal shelf rockfish (DSR) assemblage (yelloweye, quillback, copper, rosethorn, canary, China, and tiger rockfish) is assessed on a biennial cycle, with full stock assessments conducted in odd calendar years to coincide with new survey data. This year, although an odd year, we present an executive summary as we develop a statistical age-structured model for 2014. In addition, we are transitioning from a submersible (Delta) to a remote operated vehicle (ROV) as our visual survey vehicle. The future agestructured model will incorporate submersible/ROV density estimates, commercial, sport, and subsistence fishery data, and International Pacific Halibut Commission survey data. The last full stock assessment can be accessed here: ftp://ftp.afsc.noaa.gov/afsc/public/Plan_Team/Nov2009/GOAdsr.pdf. In this stock assessment document, we present two options. The first option is based on our historical methodology of using the most recent survey derived yelloweye rockfish density estimates for each management area in the Southeast Outside (SEO) to calculate the total available DSR biomass. The second option was developed based on the September 2013 Plan Team discussion regarding the risk in continuing to roll forward the most recent year of survey data from each management area, rather than using a model-based approach to incorporate interannual variability. At the Plan Team’s recommendation, we present this second option: a random walk time series model estimate of biomass in which process errors are estimated as a random effects approach (Appendix 1).

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Last updated by Alaska Fisheries Science Center on 04/23/2019

North Pacific Groundfish Stock Assessments Alaska Groundfish Research