Integrating marine protected areas and spatial fisheries restrictions in ecosystem models of the Aegean Sea

The Mediterranean Sea faces significant ecological challenges, including overexploitation and climate change, that necessitate innovative management strategies. Marine Protected Areas (MPAs) serve as critical management measures in preserving biodiversity and rebuilding fish stocks. This study employed the ECOSPACE modelling framework to assess the impacts of various spatio-temporal management scenarios in the Aegean Sea, focusing on biomass, catches, and spatial distributions of marine populations. The reference scenario revealed a 6 % decline in total biomass and substantial decreases in commercially important species by 2050. While prey species at lower trophic levels showed biomass increases due to reduced predation, these gains were inconsistent across functional groups (FGs). Five scenarios explored MPA placement, extended protection within Natura 2000 areas, and offshore wind farm (OWF) integration. Results demonstrated localized biomass increases within restricted zones but highlighted trade-offs, including effort redistribution and reduced total catches in some cases. Larger MPAs with stricter protections yielded more pronounced ecological benefits, particularly for demersal and benthic species, but posed economic challenges for fisheries. Among the tested scenarios, Scenario 3, which extended the bottom trawling and purse seining restriction area, demonstrated the highest biomass gains for key commercial species with moderate trade-offs in catch, making it suitable for fisheries-focused management. In contrast, Scenarios 1 and 2, which prohibited fisheries within Natura 2000 areas, offered broader conservation benefits, supporting their use in biodiversity-driven strategies. Once in operation, the areas associated with OWFs provided modest conservation benefits, supporting the potential for multi-use marine spatial planning. The findings of the present work can provide valuable insights for policymakers, aiding the development of adaptive management plans that balance biodiversity conservation with sustainable fisheries in the Aegean Sea. Future improvements should integrate high-resolution spatial data and socioeconomic analyses for a holistic understanding.