Proposal for an extension to the mark recapture experiment to estimate toothfish population size in Subarea 48.4

1. So far a total of 929 D. eleginoides have been tagged and released at Subarea 48.4 and 25 tagged fish have been recaptured, including 23 during the latest season. 2. A preliminary assessment of D. eleginoides stock size in the Northern Area of 48.4 estimates a vulnerable biomass of between 1,000 to 2,000 tonnes. 3. The UK proposes to continue the mark-recapture experiment in Subarea 48.4 in the 2008/09 fishing season so as to allow for a full assessment of D. eleginoides stock size in the Northern in 2009. 4. Additionally, the UK proposes to commence a mark-recapture experiment in the southern area of Subarea 48.4. This has the aims of providing the data required for assessments of the population structure, size, movement and growth of both Dissostichus eleginoides and Dissostichus mawsoni in the southern area of 48.4. 5. A catch limit of 75 tonnes is proposed for D. eleginoides the northern area, where D. mawsoni will remain a bycatch species. A combined catch limit of 75 tonnes is proposed for D. eleginoides and D. mawsoni in the southern area. 6. It is proposed that catch limits are introduced for bycatch species in the Northern Area of 48.4, set at 16% Macrourus spp. and 5% Rajid spp of the catch limit for Dissostichus species. In the Southern Area, catches taken at these proportions would trigger a move-on rule. 7. The UK has submitted a complementary proposal to IMAF to amend CM 24-02, to bring the mitigation requirements for 48.4 into line with the IMAF risk assessment, such that daytime setting would be permitted if bottle tests are undertaken, and the fishing season is extended to run from 1 December to 30 November.