The occurrences of alien species in Europe results from extraction of spatial data coming from a network of Data Partners, based on species contained in the EASIN Catalogue.

EASIN-Lit also contributes to enriching the Geodatabase through screening the scientific literature and retrieving geo-referenced data.

Official Surveillance systems on invasive alien species of EU concern set up by Member States to comply with the provisions of regulation 1143/2014 contribute to the update of the EASIN geodatabase.

The process of retrieving the data from the Data Partners is done through the EASIN Data Broker system, which is able to retrieve the species occurrences and related information (date, source) from different kind of data sources and store them in a normalized database structure.

Data are subsequently transformed by converting the harvested data to the EASIN Data Model through the following steps: Validation, Cleansing and Standardization, Geocoding, Mapping, Application of Quality rules and finally loaded on the Geodatabase (Datawarehouse).

Data collected can be visualized on the EASIN Species Search and Mapping tools, where the maps show the presence of alien species at country, grid 10x10 km, river basin district, marine ecoregion, MSFD marine areas, and outermost regions levels. The maps generated can be downloaded and exported. In addition, data collected through the Alien Species Geodatabase contributed to the preparation of the baseline distributions of species of Union Concern under EU Regulation 1143/2014.