The European Digital Twin Ocean, launched by the European Commission in 2022, aims to make ocean knowledge openly accessible and actionable through advanced digital technologies. As a key component of the EU Mission “Restore our Ocean and Waters by 2030”, it supports informed decision-making for policymakers, researchers, businesses, and citizens. EDITO serves as the core infrastructure of the European Digital Twin Ocean, integrating major European assets such as EMODnet and the Copernicus Marine Service into a unified digital framework. It combines high-resolution data with cloud and high-performance computing to enable simulations and “what-if” scenarios. In its 2025–2028 phase, EDITO will enhance usability, expand its data scope, and foster co-creation through open calls and user support, advancing toward a fully operational, globally leading digital ocean platform by 2030.

This extended abstract introduces the SURIMI model coupling frame-work, a generic solution for achieving interoperability between simulation mod-els, and demonstrates its use in the SURIMI Western Mediterranean use case.

Many marine protected areas (MPA) in Europe provide only minimal, or no protection from damaging human activities and more than half still have no fisheries restrictions at all. This is a particular concern for harbour porpoises (Phocoena phocoena) in the Inner Danish Waters, where populations have severely declined despite the presence of designated MPAs. Here, I develop an integrated individual-based modelling framework to test whether trawl-free MPAs would be more effective if relocated to highly suitable habits for harbour porpoises rather than kept in their current configuration. POSEIDON, an individual-based fisheries model, is coupled with DEPONS, a spatially explicit individual-based harbour porpoise population model to simulate fish stock depletion, porpoise population responses and adaptive fleet behaviour under current and alternative MPA designs.

Marine social-ecological systems are increasingly shaped by competition over ocean space as offshore renewable energy, fisheries, and conservation expand within shared environments. Offshore wind farms (OWFs) can re-strict access to fishing grounds while potentially altering ecological conditions, creating feedbacks between fisher behavior and fish population dynamics. These changes are not experienced uniformly across the fleet: small-scale vessels, often operating closer to shore and with more limited mobility, may be disproportionately affected by spatial restrictions. This study presents an agent-based model (ABM) that simulates heterogeneous fishing vessels operating in a spatially explicit environment with dynamic fish populations and evolving spatial constraints. Vessels differ in capacity, costs, and mobility, and decision-making strategies, allowing comparison between small-scale and large-scale fleet segments. Using the Baltic Sea around Gotland, Sweden, as a case study, the model examines how alternative OWF configurations and fisheries policies influence the distribution of fishing effort, landings, and economic outcomes across vessel types. Rather than providing predictions, the model is used for comparative scenario analysis to identify key mechanisms, trade-offs, and distributional effects in multi-use marine systems