Preliminary reports on stock status and biological information on toothfish obtained from the scientific research survey by Shinsei Maru No. 3 in 2009/10 in the SE sector of Division 58.4.3b

In accordance with the Conservation Measure 41-07 (2009), a survey was conducted in order to collect information for the stock status and biological information on toothfish in the southeast sector (24 allocated points) of Division 58.4.3b (Banzare Bank), using a commercial bottom longline vessel Shinsei Maru No. 3, from December 1 to 13, 2009. Shinsei Maru Trot line system was used as fishing gear. Total catch (excluding released weight) of Dissostichus spp. And the other by-catch species was 15.9 tonnes in the SE sector, where the catch limit of 18 tonnes was set. Dissostichus spp. Made up 16 % in number and 87.5 % in weight of the whole fish caught, while Macrourus spp. Made up 81% in number but only 11 % in weight to the total. Among two species of toothfish, Dissostichus mawsoni was dominant (82 % in number and 88 % in weight to the total). Mean CPUE of D. mawsoni was 3.4 indiv. / 1,000 hooks in number and 111 kg / 1,000 hooks in weight. D. mawsoni showed a broad modal composition at approximately 130-150 cm. Total of 60 individuals of toothfish were tagged and released during the survey. One male D. eleginoides was recaptured.