Exploratory fishing for Antarctic toothfish (Dissostichus mawsoni) in East Antarctica (Divisions 58.4.1 and 58.4.2) began in 2003. Since 2017/18, exploratory fishing has been conducted under successive research plans by Australia, France, Japan, Republic of Korea and Spain. Here, we review and update the hypothesis for toothfish stock structure across East Antarctica and links with other areas (Milestone 2.5 in WG-FSA-19/59, WG-SAM-2021/03) and evaluate the suitability of research blocks in these two Divisions.
Research on exploratory fishery and tag-recapture data, spatial patterns in larval transport, recruitment and spawning, and genetic studies supports the hypothesis that Antarctic toothfish in East Antarctica represent a single stock. It is therefore appropriate that CCAMLR considers Antarctic toothfish across Divisions 58.4.1 and 58.4.2 as a single stock.
The updated suitability review for the spatial design of the research plan in WG-SAM-2022/04 followed the approach developed in WG-SAM-2018/17 and used additional data up to 2022. The review confirmed that the location of the proposed research blocks is suitable for the plan to (1) meet its research objectives, (2) represent a viable fishery, and (3) support the further development of the stock hypothesis. We therefore recommend that CCAMLR endorses the spatial design of the research plan in WG-SAM-2022/04. For the success of this plan, exploratory fishing in Division 58.4.1 should resume immediately to allow for the collection of important data towards the objectives of the research plan WG-SAM-2022/04.
- CCAMLR should consider Antarctic toothfish in Divisions 58.4.1 and 58.4.2 as a single stock.
- The spatial design of research plan in WG-SAM-22/04 enables its research objectives to be met, represents a viable fishery and supports further development of the stock hypothesis.
- Exploratory fishing in Division 58.4.1 should resume immediately to allow for the collection of important data towards the objectives of the research plan in WG-SAM-2022/04.