Launch of the latest TEN-S Report: Swimways of European Importance (SEI) Selection Criteria Development

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As part of the Swimways programme, the TEN-S presents the “Swimways of European Importance (SEI) – Selection Criteria Development” report, a crucial step in identifying essential rivers for migratory freshwater fish in Europe.  

Drawing from the Global Swimways approach, the identification of Swimways of European Importance hinges on three criteria: biological, economic, and cultural. This report specifically focuses on the biological criteria, offering a comprehensive overview of critical swimways at Global, European, and Subregional (EU) levels. This dataset was compiled by accessing information from the IUCN and UNEP-WCMC, encompassing the status of migratory freshwater species based on the threatened Red Lists, data from the Bern Convention and Habitat Directive lists, and species richness. We considered a total of 92 migratory freshwater fish species in the SEI criteria. 

To categorize the data, we assessed the diversity of migratory fish species in European river stretches, using two thresholds based on species richness: a stricter top 10% and a more relaxed top 20%. Our findings indicate that 33% (110,000 km) of the analysed river stretches meet the 20% threshold, while 15% (around 50,000 km) conform to the 10% criteria for Swimways of European Importance. We have opted for the 20% threshold as it provides a more geographically balanced perspective and encompasses approximately 400 SEIs across Europe, as it’s possible to observe in the following map:

The pivotal role of SEI identification, grounded in species richness of the threatened/ protected status, is evident in safeguarding Europe’s essential swimways and ensuring enhanced conservation for migratory freshwater fish. Ongoing efforts focus on a detailed technical report to individually assess each swimway, evaluating migratory species and their classification. Subsequent reports will explore the barriers and fragmentation within each swimway, River Basin Management Plans, renewable energy development, Natura 2000 areas, protected area pledges, and conservation and restoration plans. This holistic approach will provide an overview of the pressures and ongoing efforts present in each swimway across Europe. 

You can download the report here:

SEI - Report on the selection criteria development

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