Alien/Invasive Mammals of the Aleutian Islands

Few land mammals are native to the Aleutian Islands unit of the Alaska Maritime National Wildlife Refuge west of Unimak Island. One exception is the red fox (Vulpes vulpes), endemic only to the larger islands in the Fox island group, Umnak, Unalaska, Akutan and Akun, and, in the same area, possibly tundra voles (Microtus oeconomus), whose origin is unclear. Humans introduced numerous land mammals. Some died out, some were removed but those that still remain are listed below.

Introduced by humans and present on islands indicated

Lagomorpha		Island(s)
European Rabbit	Oryctolagus cuniculus	Anangula, Ananiuliak, Poa, Tangik
Rodentia
Arctic ground squirrel	Cittellus parryi	Kavalga, Umnak, Unalaska,
Deer mouse	Peromyscus maniculatus	Shemya Island
House mouse	Mus musculus	Kiska, Unalaska
Norway rat	Rattus norvegicus	Attu, Kiska, Little Kiska, Rat, Amchitka, Adak, Great Sitkin, Kagalaska, Atka, Unalaska, Sedanka, Akutan, and satellite islands near these larger islands.
Roof rat	Rattus rattus	Shemya
Carnivora
Arctic fox	Alopex lagopus	originally almost all islands >1,000 acres
Red fox	Vulpes vulpes	Chuginadak, Tigalda
Artiodactyla
Caribou (reindeer)	Rangifer tarandus	Adak, Atka, Umnak, Unalaska
Cattle	Bos spp.	Umnak, Unalaska, Akun,
Sheep	Ovis aries	Unalaska, Umnak
Perissodactyla
Horse	Equus caballus	Unalaska, Umnak