The spatial ecology of Rajidae from mark-recapture tagging and its implications for assessing fishery interactions and efficacy of Marine Protected Areas

Often the ecology of a commercially fished species and the behaviour of the fishers are inextricably linked. An understanding of both species ecology and fisher behaviour are therefore fundamental for effective fisheries management. In Europe, Rajidae are commercially fished species that are vulnerable to overfishing, have historically been grouped in landings data and declines have been reported to the point of local extinction in some species. Management of these species is therefore important, however an understanding of species ecology and the way they interact with the fishery is lacking. Here we investigate how the differing ecology of four species affects interactions with the fishery by considering gear types, Marine Protected Areas, location of capture and geographic displacements. Our results demonstrate that the four species interacted differently with the fishery, for example Raja clavata were more commonly captured by static nets (69 % of recaptures) and Raja brachyura more commonly by trawlers (77 %). There were clear differences in the location of capture, depths and displacements of the four species resulting in differing interactions with existing management in the form of Marine Protected Areas. For example 53 % of R. clavata recaptures were within the boundaries of an MPA compared to 18 % for R. brachyura. These results provide important differences among species that are generally grouped by current management, emphasising the need for further species specific research to ensure effective management