in place that allow the hunting of red foxes in the Arctic fox's previous range. As with many other game species, the best sources of historical and large-scale population data are hunting bag records and questionnaires. Several potential sources of error occur in such data collections. In addition, numbers vary widely between years due to the large population fluctuations. However, the total population of the Arctic fox must be in the order of several hundred thousand animals. The world population of Arctic foxes is thus not endangered, but two Arctic fox subpopulations are. One is on Medny Island (Commander Islands, Russia), which was reduced by some 85–90%, to around 90 animals, as a result of mange caused by an ear tick introduced by dogs in the 1970s. The population is currently under treatment with antiparasitic drugs, but the result is still uncertain. The other threatened population is the one in Fennoscandia (Norway, Sweden, Finland, and Kola Peninsula). This population decreased drastically around the start of the 20th century as a result of extreme fur prices, which caused severe hunting also during population lows. The population has remained at a low density for more than 90 years, with additional reductions during the last decade. The total population estimate for 1997 is around 60 adults in Sweden, 11 adults in Finland, and 50 in Norway. From Kola, there are indications of a similar situation, suggesting a population of around 20 adults. The Fennoscandian population thus numbers around 140 breeding adults. Even after local lemming peaks, the Arctic fox population tends to collapse back to levels dangerously close to nonviability. The Arctic fox is classed as a "prohibited new organism" under New Zealand's Hazardous Substances and New Organisms Act 1996, preventing it from being imported into the country. See also Arctic rabies virus References Further reading Nowak, Ronald M. (2005). Walker's Carnivores of the World. Baltimore: Johns Hopkins Press. . External links State of the Environment Norway: Arctic fox Smithsonian Institution – North American Mammals: Vulpes lagopus Photo Gallery by islandsmyndir.is Fox, arctic Holarctic fauna Mammals described in 1758 Mammals of Europe Mammals of Asia Mammals of Greenland Mammals of Iceland Mammals of North America Mammals of Russia Mammals of Canada Mammals of the United States Mammals of the Arctic Taxa named by Carl Linnaeus Vulpes