Research plan for the exploratory longline fishery for Dissostichus spp. in SSRUs C, E and G in Division 58.4.1 in 2012/13 (this is a revision of WG-SAM-12/10 Rev. 1)

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 1000-2000 t per SSRU in 58.4.1 and 100-1500 t per SSRU in 58.4.2. During the 2003-2007 fishing seasons, 3,434 toothfishes 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 foodweb of toothfish stared to be studied recently only in the southern Ross Sea. 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, E, and G in Division 58.4.1 is very important to consider proper way for effective utilities of the population and ocean. Therefore, Korea notifies the participation in exploratory fishery for Dissostichus spp. in the SSRUs C, E, and G 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. The main objective of this scientific research plan is to assess the stock status of Dissostichus spp. in SSRUs C, E, and G in Division 58.4.1. We will collect the catch and effort, tagged and released, and recaptured dada and biological data to estimate biomass for Dissostichus spp. and assess the ecosystem-based fisheries. For the 1st year of this research, we will collect and analyze catch, effort, and biological data such as length, weight, gonadial development, otolith and muscle. During the 2nd year, we will collect the same data as the 1st year continuously. We will also submit the primarily results on the comparing catch rate between trot line and Spanish line, and estimations of biological parameters based on the collected data from the 1st research. For the 3rd year research, we will collect the same data consequently, and we will submit the results on the comparing results among the estimated biomass for Dissostichus spp. using three different analysis and ecosystem-based risk assessment.