South Africa and Japan revised the next season’s (2017/18) research plan in Subarea 48.6 using the latest CCAMLR C2 and Observer data, following the recommendations and notification from WG-SAM meeting in 2017 (e.g., WG-SAM-17 report, paragraph 4.4, 4.10, and 4.18, 2017) and data extracts provided by the CCAMLR Secretariat on the 27th of July, 2017 were used.

The estimated median stock sizes in research blocks 48.6_2E (southeast part of 48.6_2), 48.6_3, and 48.6_4 are 4864.30, 3132.55, and 8044.33 tonnes, respectively, when applying the Chapman method. Chapman method considers tags that were released in the most recent year as effective for the biomass estimation, except for 48.6_4 which considered the last three years when estimating biomass. The estimated median stock sizes in blocks 48.6_2W, 48.6_2E, 48.6_3, and 48.6_4 were 189.56, 306.31, 125.05, and 969.14 tonnes, respectively, when CPUE by sea bed area methods are used considering the relevant information of reference area (recent median CPUE, estimated biomass and updated area size) recommended in the WG-SAM-16/18 Rev.1.

We propose to continue the current research operation in Subarea 48.6 for the next fishing season with the same survey design.