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100 of the World's Worst Invasive Alien Species

IUCN. Species Survival Commission. Invasive Species Specialist Group.

The list of “100 of the World’s Worst Invasive Alien Species” is designed to enhance awareness of the fascinating complexity, and also the terrible consequences, of invasive alien species. Species were selected for the list according to two criteria: their serious impact on biological diversity and/or human activities, and their illustration of important issues surrounding biological invasion.