Report of the Baltic International Fish Survey Working Group

According to the terms of reference an important aspect of the meeting of the working group was the combination of theresults of the acoustic and trawl surveys carried out in the Baltic Sea in summer and autumn 2003 and spring 2004. Theresulting indices are used by the Baltic Fisheries Assessment Working Group as fishery independent estimates.The working group recommended that the acoustic estimates for herring and sprat can be used without any restrictionsand that the combined estimates represents the stock size and the distribution pattern of both species.Furthermore, the results of the trawl surveys in autumn 2003 and spring 2004 represent the stock size and thedistribution pattern of the two target species cod and flatfish. The intensive checks of the used standard gears whichbased on the description in the manuals have shown that the data of the trawl surveys are not significantly influenced bya change quality of the gears.