Discard sampling of Plaice (Pleuronectes platessa) and Cod (Gadus morhua) in the North Sea by the Dutch demersal fleet from 2004 tot 2008

The PVis discard data used in the analysis presented in this report clearly shows where and when most discarding takes place. Although previous analysis (Aarts & van Helmond 2007) and the latest Flatfish Benchmark Assessment (2009), indicate that the data cannot be incorporated into the ICES stock assessment, it still provides an important reference points that can be used to evaluate the current DCR discard estimates and methods used. In 2009 Wageningen IMARES started a new DCR sampling program. The most remarkable difference with the previous program is the integration of self-sampling next to a less intensive observer program. We encourage this initiative, since the increase of discard data available over space and time will be of great value, but strongly recommend clarity of sampling procedures, thorough training and intensive communication with fishermen. Hence, inaccurate data on discards will have a significant impact on future management strategies