The invasion of two species of social wasps (Hymenoptera, Vespidae) to the Faroe Islands.
Two species of social wasps have established in the Faroe Islands in 1999 - common wasp Vespula vulgaris and German wasp Vespula germanica. The population growth, and dispersal in the Faroes has been followed in detail through correspondence and contact with local residents and authorities throughout the Faroes. Collected wasps have been identified, and nest eradication data from the local municipalities is also presented. In total there have been 1.222 nests located and destroyed, mostly in Tórshavn, where they were first introduced, but nests have also been found on neighbouring islands. Both the introduction and the spread within the Faroes suggest a strong relationship with human settlements and travel. Social wasps have established on four out of 18 islands - all of which are connected by land, suggesting that their spread within the islands is also human aided. With no active biosecurity measures to prevent the introduction of invasive alien species to the Faroes, we predict that the introduction of more species of social wasps to be very likely, and wasps already present will likely invade new islands. Although social wasps represent a public nuisance in the Faroes, the potential ecosystem impacts are grossly underappreciated and understudied.