2015 Assessment of the Skate Stock Complex in the Bering Sea and Aleutian Islands
The Bering Sea and Aleutian Islands (BSAI) skate complex is managed in aggregate, with a single set of harvest specifications applied to the entire complex. However to generate the harvest recommendations the stock is divided into two units. Alaska skate (Bathyraja parmifera), the most abundant skate species in the BSAI, is in Tier 3 so harvest recommendations are made using the results of an age-structured model. The remaining species (“other skates”) are managed under Tier 5 due to a lack of data. The Tier 3 and Tier 5 recommendations are combined to generate recommendations for the complex as a whole.
Alaska skate is found mainly on the eastern Bering Sea (EBS) shelf, while “other” skates occur mainly on the EBS slope and in the AI. Because the EBS slope and AI trawl surveys are biennial, full information regarding the BSAI skate complex is available only every other year. As a result, full assessments for the BSAI skate complex are only conducted in years when all three BSAI surveys occur. In “off” (odd) years, an executive summary is prepared that incorporates updated catch information, results from the EBS shelf survey (conducted annually), and updated harvest recommendations from a new run of the Alaska skate projection model.