What is a target or a bycatch stock?

In the context of regionalization and the implementation of the Landing Obligation, there has been an increased interest for defining the ‘status’ of the stocks. In fact, the existing Multi-Annual Plans are based on a list of ‘target’ and ‘bycatch’ stocks with potential differentmanagement measures associated to. ICES has already been asked to advice on removing TACs for stocks based on the assumption that the stocks were bycatch stocks and the TACs were not the most relevant management measure to manage these stocks. The main driver for removing TACs was also to release the potential chocke effect of these species. But when is a species/stock a target or a bycatch? Are there only two categories? Can’t species been changing status among year and/or fleets?
We propose a method that enables the appropriate classification of individual stock as either target or bycatch and test and apply it over different region (i.e. the Celtic Sea, North Sea and Bay of Biscay). A tool has then been developed to easily assess stock status among the métiers fishing in these areas.