NATIONAL DATABASES
Belgium (BE)
Invasive species in Belgium: http://ias.biodiversity.be/ias/
Global Register of Introduced and Invasive Species: https://www.gbif.org/dataset/6
Germany (DE)
Aquatic alien species in German inland and coastal waters http://www.aquatic-aliens.de/
NEOBIOTA: http://www.neobiota.de/
Denmark (DK)
Danish Ministry of the Environment: http://www.naturstyrelsen.dk/
Spain (ES)
Exotic Invasive species in the Iberian Peninsula: http://invasiber.org/
Ireland (IE)
Invasive Alien species in Northern Ireland: http://www.habitas.org.uk/invasive/
Netherlands (NL)
Overview of biodiversity of the Netherlands – Exotics: http://www.nederlandsesoorten.nl/node/19
Norway (NO)
Norway Alien Species: http://www.artsdatabanken.no/
United Kingdom (UK)
Non-native species secretariat: http://www.nonnativespecies.org/home/index.cfm
England Invasion Biology: http://www.brc.ac.uk