Report of the Baltic Fisheries Assessment Working Group (WGBFAS) : 14-21 April 2015, ICES HQ, Copenhagen, Denmark

The ICES Baltic Fisheries Assessment Working Group (WGBFAS) met 14-21 April 2015 (Chair: Mare Storr-Paulsen, Denmark), with 28 participants and 9 countries represented. The objective of WGBFAS was to assess the status of the following stocks: 1 ) Sole in Division IIIa, SDs 20-22 2 ) Cod in Kattegat, Cod in SD 22-24, Cod in SD 25-32 3 ) Herring in SD 25-27, 28.2, 29 and 32, Herring in SD 28.1 (Gulf of Riga), Herring in SD 30, Herring SD 31. 4 ) Sprat in SD 22-32 5 ) Plaice 21-23, Plaice 2425 6 ) Flounder 22-23; 24-25; 26+28 and 27+29-32, Brill 2232, Dab 2232, and Turbot 2232 (survey trends) WGBFAS also identified the data needed, for next year’s data call with some suggestions for improvements in the data call as well as in InterCatch. The report contains an introduction with the summary of other WGs relevant for the WGBFAS, country specific fishery description, the methods used, and ecosystem considerations. The results of the analytical stock assessment or survey trends for the species listed above are then presented with all the stocks with the same species in the same sections. The report ends with references, list of Working Documents, recommendations and Stock Annexes. In first quarter 2015 the Baltic cod stocks and the plaice stocks were benchmarked. As a result the Baltic cod stocks now have to apply a splitting key in SD 24 were both stocks are present. This has changed the assessment from being an area based assessment to now being a stock based assessments and has implications for the advice. The principle analytical models used for the stock assessments were XSA and SAM. For most flatfishes, CPUE trends from bottom trawl surveys were presented (except plaice 2425 and her31 using relative SSB from SAM and XSA, respectively). Ecosystem changes have been analytically considered in the following stock assessments: Herring in SD 25-27, 28.2, 29 and 32, and Sprat in SD 22-32, in form of cod predation mortality. Last year a very large retrospective pattern in th