Proposal for a research plan for the exploratory longline fishery for Dissostichus spp. in 2014/15 in Division 58.4.4

Regarding the low levels of stocks of Dissostichus spp. and the high levels of IUU fishing, CCAMLR decided to close the fishery in 2002 in division 58.4.4. Since 2008 only one vessel, Shinsei maru No. 3, has conducted research fishing in accordance with a research plan submitted under CM 24-01. France notifies its wish to collaborate in this research fishery over the coming years in order to participate in the tagging program and achieve a robust stock assessment. The aim is to provide advice on a catch limit according to CCAMLR decision rules and allow an earlier decision to reopen this area. This paper presents a proposal for a research plan for 2014/2015. For SSRU C, further developments of the assessment of Dissostichus eleginoides using a CASAL model and a simple Petersen biomass estimate derived from tagging data are proposed. The CASAL model structure is improved with three scenarios tested 1/ base case model without IUU catch; 2/ including 22% of IUU catch supposed in Division 58.4.4; 3/ IUU catch estimated within the model. For the run 3/, B0 is estimated at around 640 tonnes and the estimate of total amount of IUU catch is 160 tons. With Petersen’s method, geometric mean stock abundance estimate is 434 tons. Stock size of D. eleginoides in SSRU D was only estimated using comparative CPUE method with a value of 739 tons. Given no sufficient robust results and a lack of data recapture, the total research catch limits agreed in 2013 for SSRU C (25 tons) and for SSRU D (35 tons) were likely to result in sufficient tag recaptures to substantially refine the stock assessment.