In the Division 58.4.1 there are two stocks; one extends from the SSRU 58.4.1C to the SSRU 58.4.2A, and the other one to the SSRU 58.4.1H. The population sizes were vulnerable with a big range of about 1,000-2,000 t per SSRU in 58.4.1 and 100-1,500 t per SSRU in 58.4.2. During the 2003-2007 fishing seasons, 3,434 Dissostichus spp. were tagged and released, but only 5 fishes among them have been recaptured which were not enough data to estimate stock biomass for considering the precautionary catch limit. The food-web of Dissostichus spp. started to be studied recently only in the southern Ross Sea. Some studies on biology of the fish have been studied, but those are still not enough to assess the stocks and consider proper management measures. Base on CCAMLR’s fishery report on 58.4.1 area as a whole is still data-poor fishery and is showing low recapture rate mentioned above. Consequently, providing catch and effort data, analyzing biological samples, and collecting recapture data focusing on SSRUs C and E in Division 58.4.1 is very important to consider proper ways for effective managements of the population and ocean.
Korea notifies the participation in exploratory fishery for Dissostichus spp. in the SSRUs C and E in Division 58.4.1 from 2012/2013 season to 2014/2015 using Korean commercial bottom longline vessel, NO. 3 INSUNG in accordance with paragraph of CM 24-01 and paragraph 6 (iii) of CM 21-02 in 2012, and this plan is one of the processes of the notification.
The main objective of this scientific research plan is to assess the stock status of Dissostichus spp. in SSRUs C and E in Division 58.4.1. We will collect the catch and effort, tagged and released, recaptured and biological data to estimate biomass of Dissostichus spp. and evaluate migration and distribution of developmental maturity and size stage. For the 1st year (2012/2013) of this research, we collected and analyzed/will analyze the catch, effort, and biological data such as length, weight, gonadal development, otolith and muscle. However, the results were not good enough according to lack of data because of the bad sea-ice condition for the survey. Therefore, for the 2nd year (2013/2014), we will extend the sample size of catch and fishing efforts, and biological data, and also submit the primarily results on the comparing catch rate between trot line and Spanish line, and estimations of biological parameters relating to productivity based on the collected data from the 1st and 2nd researches. During the 3rd year, we will collect the same data as the 2nd year continuously. We will also submit the complete results for all three year researches such as biomass for Dissostichus spp. using CASAL model and ecosystem-based risk assessment, and consider proper measurements for the fishery management.