Résumé
Sustainable management of living resources must reconcile biodiversity
conservation and socioeconomic viability of human activities. In the case
of fisheries, sustainable management design is made challenging by the
complex spatiotemporal interactions between fish and fisheries. We develop
a comprehensive metapopulation framework integrating data on species
life-history traits, connectivity and habitat distribution to identify
priority areas for fishing regulation and assess how management impacts
are spatially distributed. We trial this approach on European hake
fisheries in the north-western Mediterranean, where we assess area-based
management scenarios in terms of stock status and fishery productivity to
prioritize areas for protection. Model simulations show that local fishery
closures have the potential to enhance both spawning stock biomass and
landings on a regional scale compared to a status quo scenario, but that
improving protection is easier than increasing productivity. Moreover, the
interaction between metapopulation dynamics and the redistribution of
fishing effort following local closures implies that benefits and
drawbacks are heterogeneously distributed in space, the former being
concentrated in the proximity of the protected site. A network analysis
shows that priority areas for protection are those with the highest
connectivity (as expressed by network metrics) if the objective is to
improve the spawning stock, while no significant relationship emerges
between connectivity and potential for increased landings. Synthesis and
applications – Our framework provides a tool for 1) assessing area-based
management measures aimed at improving fisheries outcomes in terms of both
conservation and socioeconomic viability and 2) describing the spatial
distribution of costs and benefits, which can help guide effective
management and gain stakeholder support. Adult dispersal remains the main
source of uncertainty that needs to be investigated to effectively apply
our model to fisheries regulation.