Within the ICES framework, catch advice for Data Limited Stocks (DLS) that have a representative, survey-based SSB-index falls within ICES-category 3. If F/FMSY proxies can be estimated for such a stock, advice of category 3.1 can be given; this category has a MSY-objective. However, if these proxies cannot be estimated, advice of category 3.2 is given, with the precautionary approach as objective; no further decline in the stocks is then the objective.
Currently, there are no methods to estimate F/FMSY proxies in line with the MSY approach for DLS commercially fished with fishing gears characterized by a dome-shaped size selectivity. Thus no catch advice with MSY-objective can be given for these stocks. The WOT IJsselmeer survey provides the SSB-index used as basis for our advice on IJsselmeer pikeperch and perch. However, since the fisheries of these stocks has dome-shaped selectivity, this survey currently cannot be used to its full potential in our advice on fisheries management.