100 of the World's Worst Invasive Alien Species is a list of

invasive species An invasive species otherwise known as an alien is an introduced organism that becomes overpopulated and harms its new environment. Although most introduced species are neutral or beneficial with respect to other species, invasive species ad ...

compiled in 2014 by the

Global Invasive Species Database The Global Invasive Species Database is a database of invasive species around the world run by the Invasive Species Specialist Group (ISSG) of the International Union for Conservation of Nature The International Union for Conservation of Nature ...

, a database of invasive species around the world. The database is run by the Invasive Species Specialist Group (ISSG) of the

International Union for Conservation of Nature The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...

(IUCN). The ISSG acknowledges that it is "very difficult to identify 100 invasive species from around the world that really are 'worse' than any others."

Criteria for inclusion

Two criteria were used in selecting items for the list: * An invasive species' "serious impact on biological diversity and/or human activities" and * That species' "illustration of important issues surrounding biological invasion" According to the ISSG, "only one species from each genus was selected."

List of species

;Notes

References

{{Reflist 2014-related lists Lists of invasive species Lists of worsts