Weasel

Weasels are mammals in the genus Mustela of the Mustelidae family. Originally, the name "weasel" was applied to one species of the genus, the European form of the Least Weasel (Mustela nivalis). Early literary references to weasels, for example their common appearances in fables, refer to this species rather than to the genus as a whole, reflecting what is still the common usage in the United Kingdom. In technical discourse, however, as in American usage, the term "weasel" can refer to any member of the genus, or to the genus as a whole. Of the 16 extant species currently classified in the genus Mustela, ten have "weasel" in their common name. Among those that do not are the stoat or ermine, the two species of mink, and the polecats or ferrets.

Weasels vary in length from fifteen to thirty-five centimeters (six to fourteen inches), and usually have a light brown upper coat, white belly and black fur at the tip of the tail; in many species, populations living at high latitudes moult to a white coat with black fur at the tip of the tail in winter. They have long slender bodies, which enable them to follow their prey into burrows. Their tails are typically almost as long as the rest of their bodies. As is typical of small carnivores, weasels have a reputation for cleverness and guile. They also have tails that can be anywhere from 22-33  cm long and they use these to defend the food they get and to claim territory from other weasels. The average weasels weighs about 3kg-5kg.

Weasels feed on small mammals, and in former times were considered vermin since some species took poultry from farms, or rabbits from commercial warrens. Certain species of weasel and ferrets, have been reported to perform the mesmerizing weasel war dance, after fighting other creatures, or acquiring food from competing creatures. In folklore at least, this dance is particularly associated with the stoat.

Collective nouns for a group of weasels include boogle, gang, pack, and confusion.

Weasels are found all across the world except for Australia and neighbouring islands.

Species

The following information is according to the Integrated Taxonomic Information System, and IUCN 2006 for the extinct Mustela macrodon.

Mustela africana	Desmarest, 1800	Tropical weasel	South America
Mustela altaica	Pallas, 1811	Mountain weasel	Europe & Northern Asia Southern Asia
Mustela erminea	Linnaeus, 1758	Stoat Ermine Short-tailed weasel	Australia (non-native) Europe & Northern Asia North America Southern Asia (non-native)
Mustela eversmannii	Lesson, 1827	Steppe polecat	Europe & Northern Asia Southern Asia
Mustela felipei	Izor and de la Torre, 1978	Colombian weasel	South America
Mustela formosana	Lin et Harada, 1998	Taiwan high-mountain least weasel	Taiwan
Mustela frenata	Lichtenstein, 1831	Long-tailed weasel	Middle America North America South America
Mustela itatsi	Temminck, 1844	Japanese weasel	Japan & Sakhalin in Russia
Mustela kathiah	Hodgson, 1835	Yellow-bellied weasel	Southern Asia
Mustela lutreola	(Linnaeus, 1761)	European mink	Europe & Northern Asia
Mustela lutreolina	Robinson and Thomas, 1917	Indonesian mountain weasel	Southern Asia
Mustela nigripes	(Audubon and Bachman, 1851)	Black-footed ferret	North America
Mustela nivalis	Linnaeus, 1766	Least weasel	Europe & Northern Asia (non-native) North America Southern Asia (non-native)
Mustela nudipes	Desmarest, 1822	Malayan weasel	Southern Asia
Mustela putorius	Linnaeus, 1758	European Polecat	Europe & Northern Asia
Mustela sibirica	Pallas, 1773	Siberian weasel	Europe & Northern Asia Southern Asia
Mustela strigidorsa	Gray, 1855	Black-striped weasel	Southern Asia
Mustela subpalmata	Hemprich and Ehrenberg, 1833	Egyptian weasel	Egypt

¹ Europe & Northern Asia division excludes China.