We analysed the available data from vessel and scientific observer logbooks from the exploratory fishery for Antarctic toothfish (Dissostichus mawsoni) and Patagonian toothfish (D. eleginoides) in CCAMLR subarea 48.6 (South East Atlantic). This report summarises the catch, effort, timing, depth, location, size structure and maturity of Dissostichus spp. Information on the composition of bycatch species caught in the fishery over the period 2003-4 to 2011-12 are also presented. For the Antarctic toothfish, accumulated catch across years yielded 1,353 tons with the majority of the catch coming from SSRUs 48.6G and 48.6E. For the Patagonian toothfish the accumulated catch was 349 tons and almost all was reported exclusively in the SSRUs 48.6A and 48.6G. Most of the catches were reported by vessels from Japan (58%) and Rep. of Korea (31%) and to a lesser extent, from South Africa (7%) and Norway (4%).
Unstandardized raw catch and effort data suggested that the median catch per unit of effort in Antarctic toothfish has generally increased over the course of the fishery whilst it has decreased over time for Patagonian toothfish. In both species average length of catches is larger in females. Antarctic toothfish is caught at deeper waters and have a larger mean length than Patagonian toothfish. There is not evidence of truncation in the overall length frequency distribution of both species, although some evidence of reduction in the mean fish length has been observed in the last three fishing seasons. In both sexes, high frequencies of maturity stages 2 and 3 were observed in Antarctic toothfish whereas for Patagonian toothfish immature (stage 1) fish were most frequently observed. The bycatch for both toothfish species is composed of few species. In term of biomass, the most important bycatch species are grenadiers and blue antimora. A total of 3,828 individuals of toothfish have been tagged in this area but only 19 have been recaptured. We concluded that from the data examined from the fishery to date there is not evidence for substantial changes in the population structure of both species in this subarea.