Operationalising Ecologically or Biologically Significant Marine Areas criteria for ecosystem-based conservation and management : the Bay of Biscay case

Marine ecosystems face significant declines in biodiversity and health due to human activities and environmental changes. To address this, global and regional policies aim to protect 30 % of marine areas by 2030, known as the ‘30 × 30’ target. Achieving this goal in a way that effectively safeguards biodiversity requires a comprehensive strategy that incorporates the full complexity of ecosystem processes and functions. This study introduces a framework for enhancing ecosystem-based conservation and management by leveraging the Ecologically or Biologically Significant Marine Area (EBSA) criteria established under the Convention on Biological Diversity. Our approach provides a structured workflow for integrating data from multiple sources, guided by the EBSA criteria, for a holistic assessment of the relative ecological significance across different regions. By focusing on the spatial distribution of ecological significance, the framework brings the EBSA identification process to a spatial resolution suitable for informing regional or national decision-making. It supports the identification of priority areas for conservation that goes beyond single-species or habitat protection by incorporating ecosystem-level processes and offers a foundation for broader marine spatial planning and management initiatives. Furthermore, it includes a method for evaluating data quality and spatial coverage, enabling spatially explicit assessments of uncertainty and data gaps. Tested in the Bay of Biscay, our approach offers a robust and adaptable framework for both data-rich and data-poor regions, thereby enhancing spatial management and conservation efforts while ensuring traceability and transparency.