The MERLIN web app

The MERLIN web application, integrated into the WaterWebTools platform, is an interactive webtool that enables users to obtain a Europe-wide overview of the status of water bodies, habitats, and species linked to the Water Framework Directive and the Habitats Directive.

Users can explore Europe-wide maps, navigate between Natura 2000 sites, and access detailed information on protected habitat types and species listed in Annex I and II of the Habitats Directive. Data can be extracted for synthesis, analysis, and further scientific or management assessments. The webtool also demonstrates a practical application of the MERLIN modelling workflow in specific water basins as detailed in Baattrup-Pedersen et al. (2026), including modelling of the societal benefits as described in Garcia et al. (2025) and a cost–benefit analyses for these water basins as described in Kok et al. (2025).

The application builds on results from a Europe-wide screening (Duarte et al. 2023) and the Natura 2000 database (version 2021; EC, 2022), processed and made available in Baattrup-Pedersen et al. (2025). For guidance on how to use the webtool, please consult the user guide and supporting videos.