National Institute for Environmental Studies Invasive Species of Japan Japanese | English
  1. Invasive Species of Japan >
  2. Mammals >
  3. Mustela itatsi

Mustela itatsi

Basic information
Scientific name Mustela itatsi

Click to magnify

Common names Japanese weasel
Higher taxon Mustelidae, Carnivora, Mammalia
Natural range Honshu, Shikoku, Kyushu and several peripheral islands of Japan
Habitat Lowland. Sometimes montane area.
Invasion information
Range in Japan Hokkaido and peripheral islands (Rishiri and Rebun Is.), Izu Islands (Toshima, Miyakejima, Hachijojima, and Aogashima Is.), Goto Islands, Tokara Islands, Amami Islands (Kikai, Okinoerabu, Yoronjima Is.), Okinawa Islands (Iejima, Kumejima, Zamami Is.), Daito Islands, Sakishima Islands (Miyako, Irabu, Shimoji, Hateruma Islands), etc. Range in Japan
Origin Japan
Date Hokkaido: 1880s; The first introduction to small islands for biological control of rats is that to Tokara Islands in 1925-27.
Route Deliberate: For rat control (in almost small islands); For fur (in Hokkaido).
Impact Predation on native species and domestic animals.
Native organism(s) affected: Small mammals, reptiles (diurnal lizards and snakes), birds, insects, etc.
Regulation in Japan No action for prevention, mitigation, control, or eradication.
Introduced range in other countries None.
Reference Notes
  • Abe (ed) (1994) A Guide to Mammals of Japan. Tokai Univ. Press, Hatano (in Jpn)
  • Ecol Soc Jpn (ed) (2002) Handbook of Alien Species in Japan. Chijinshokan, Tokyo (in Jpn)
  • Hasegawa (1999) Impacts of the introduced weasel on the insular food webs. in: Ota (ed) Tropical Island Herpetofauna: Origin, Current Diversity, and Conservation. Elsevier Science. pp.129-154
  • Kawabata (ed) (1996) The Encyclopedia of Animals in Japan 1 Mammals I. Heibonsha, Tokyo (in Jpn)
  • Ohdachi et al. (2009) The Wild Mammals of Japan. Shokabo, Kyoto.
  • Okinawa Prefectural Museum (ed) (1996) Naturalized Animals. Okinawa Prefectural Museum (in Jpn)
  • Sekiguchi et al. (2002) Food habits of introduced Japanese weasels (Mustela itatsi) and impacts on native species of Zamami Island. Mammal Sci. 42(2), 153-160 (in Jpn)
  • Shiraishi (1982) The weasel as a rat-control agent. Collecting and Breeding. 44(9), 414-419 (in Jpn)
  • etc.
100 of the Japan's Worst Invasive Alien Species