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invasive alien species

Alternative name(s): invasive species/ alien species/ non-native species

Acronym: IAS

Definition Source References

A species introduced outside its natural past or present distribution whose introduction and/or spread threaten biological diversity.

Scenarios and models assessment

Species whose introduction and/or spread by human action outside their natural distribution threatens biological diversity, food security, and human health and well-being. Alien refers to the species' having been introduced outside its natural distribution (exotic, non-native and non-indigenous are synonyms for alien). Invasive means tending to expand into and modify ecosystems to which it has been introduced. Thus, a species may be alien without being invasive, or, in the case of a species native to a region, it may increase and become invasive, without actually being an alien species.

Americas assessment, Africa assessment, Asia-Pacific assessment, Pollination assessment, Land degradation and restoration assessment, Europe and Central Asia assessment, Sustainable use assessment, Global assessment (1st work programme)

A species that, once it has been introduced outside its native distributional range, has a tendency to spread over space without direct human assistance.

See Invasive alien species.

Europe and Central Asia assessment, Americas assessment, Asia-Pacific assessment, Global assessment (1st work programme)