Determining long‐term changes in a skate assemblage with aggregated landings and limited species data

摘要: Sustainable fisheries management requires assessment of exploited populations and communities. Traditional stock methods need species‐specific input data, which for skates have only recently become available in Europe. To overcome this limitation, a Bayesian multispecies biomass production model was developed. In addition to aggregated landings, data are short time series with information (landings indices). Applying the approach four main skate species group two species, all managed together Bay Biscay (Northeast Atlantic), long‐term changes assemblage composition were identified. Since 1990s, Leucoraja naevus became increasingly dominant, while contributions other three (Raja brachyura, Raja clavata montagui) declined. The abundance grouped fullonica L. circularis has also strongly decreased, suggesting overexploitation. All except expected increase over next decade under current harvest rates. Currently, considered here single fishing quota making it unlikely that most depleted will recover soon. modelling bears promise harvested assemblages is certain periods.