Celtic Invasive Plants database

Alien Invasive Species (AIS) represent one of the principal threats to humanity due to their substantial ecological, social, and economic impacts. The international effort to harmonize national AIS checklists and databases is often hindered by the data fragmentation across platforms. The Celtic Fringe, a biogeographically coherent unit within the European Atlantic Floristic Region, includes part of the Iberian Peninsula, France and the British Islands—is notable for its extensively documented flora. Here, we present the first unified AIS checklist and georeferenced occurrence database for the entire Celtic Fringe, mapped at a 10×10 km UTM grid resolution. Occurrence data were aggregated from public datasets, while the harmonized 271-taxa AIS checklist was developed through the integration of national and international sources. The resulting database comprises 164974 occurrences, each enriched with taxonomic, floristic, and administrative metadata to enhance usability across multiple geographic and governance levels. This harmonized and standardised resource is designed to support AIS management strategies at local, national, and transnational scales, while facilitating conservation planning and advancing research on invasion dynamics.