EPPO Global Database

EPPO Reporting Service no. 01 - 2013 Num. article: 2013/021

The European Environment Agency new publication on invasive alien species indicators in Europe

New introductions of alien species into Europe across all taxonomic groups and environments are known to be increasing. However, due to constraints and methodological difficulties (e.g. limited data availability, ambiguity in the definition of terms), robust and sound ‘alien indicators’ have only recently been made available. The European Environment Agency commissioned a project to critically review and improve alien indicators.
Indicators had been identified in the SEBI 2010 pan-European initiative. These indicators are still considered as relevant, but may be improved:
  • Cumulative numbers of alien species in Europe since 1900: the temporal coverage could be expanded to 1500 or 1800, and pathways of entry could be included.
  • Costs of IAS in Europe: the numbers could be updated.
Furthermore, new indicators need to be developed to answer the policy questions and needs:
  • The IUCN Red List Index of impacts of IAS: this index measures the changes observed in the overall extinction risk of species that are included in the IUCN Red List;
  • The combined index of invasion trends: this index is based on the number and distribution of 542 alien species and 2871 species-country records (in European countries with different climates, country size and development status).


Rabitsch W, Essl F, Genovesi P ; Scalera R (2012) Invasive alien species indicators in Europe - A review of streamlining European biodiversity (SEBI) Indicator 10. European Environment Agency. EEA Technical report No 15/2012. 44 p