Possible reductions in Barents Sea surveys„a test of its influence on Northeast Arctic cod assessment quality

No abstracts are to be cited without prior reference to the author.

The problem of funding could lead to fewer and less frequent surveys. This study evaluated how such a reduction may affect the quality of Northeast Arctic (NEA) cod stock assessment, which relies on the results of survey data. Based on data from the ICES Arctic Fisheries Working Group collected for the period from 1946 to 2010, VPA/XSA stock assessments were performed in FLR with different assumptions on possible reduction in surveys. For all explored cases of reduced frequency of surveys a serious deterioration of the NEA cod assessment quality was observed. Retrospective patterns of SSB estimates demonstrate possible deviation of up to 55% and the same effect is observed for total stock estimates. If such a situation becomes real, it may lead to serious under/overestimation of the stock and TAC. In addition, in current ICES practice the results of NEA cod assessment are used for NEA haddock assessment and capelin TAC prediction, for which cod consumption is taken into account. Thus a decrease in cod assessment quality will influence the quality of NEA haddock and capelin assessments and advice. It was also concluded that reductions in survey frequency may reduce the quality of assessments for other species as these surveys are multispecies.