Beyond the 30x30 target: Science-informed marine protected area networks outperform random and opportunistic designs

The Mediterranean Sea, a biodiversity hotspot and one of the most heavily exploited marine regions worldwide, falls short of efficient protected areas. To address this gap, we developed an integrated framework combining a spatially explicit multi-species ecosystem model with regional climate and biogeochemical models to assess the ecological and fisheries outcomes of six fully protected marine protected area (MPA) network scenarios, expanded to 30% coverage. Scenarios included current MPA expansions, random placements and science-informed designs based on ecological, social and economic criteria. Science-informed networks consistently outperformed others, yielding higher biomass recovery, greater spillover benefits and, and lower fisheries losses. They also triggered top-down trophic cascades, reversing the “fishing down the food web” trend and enhancing high trophic level biomass. Large, aggregated offshore MPAs offered the best outcomes in balancing biodiversity conservation and sustainable fisheries, underscoring the importance of science-driven planning for achieving global conservation targets in the Mediterranean and beyond.