The toothfish fishery in the Amundsen Sea region is operating under a research plan developed by the Scientific Committee in 2014 designed to provide data to support a two-area stock assessment model. The slope and shelf area within the Amundsen Sea (Small-Scale Research Units 882C-G) is showing improvements in tag recaptures within the four research blocks. However, the seamounts in the north (Small-Scale Research Unit 882H) have shown a lack of spatial representation within the seamount complex, decreasing catch limits, and limited recapture data. Although age data are becoming available from other Members, there are no agreed criteria for aggregating age data among laboratories.
We recommend that the Working Group recommend to the Scientific Committee that a workshop on age determination and aggregation of age data for Dissostichus spp. be held, following the endorsement by WG-FSA-2021 (SC-CAMLR 40, Annex 7, Paragraph 3.94). We further recommend that Members be encouraged to continue to make their age data available, and the Secretariat correspond with those Members engaged in otolith ageing to determine how to integrate age reading data into the existing CCAMLR database.
An alternative plan for structuring the fishery in SSRU 88.2H is needed to improve mark recapture data and to better index the biomass for the seamount complex. We recommend the development of a structured fishing approach. We recommend interested Members discuss a way forward to achieve improved structured fishing during WG-FSA-2022.
We further recommend that the approach for setting catch limits in the Amundsen Sea region research blocks be improved, to allow for structured fishing to enable improved data collection, to allow development of a stock assessment for the region.
We recommend that although tag recapture levels are low in individual research blocks, the total annual tags available may be adequate for further investigation of the two-area integrated assessment model for the ASR.