The stoat (Mustela erminea) is a small mammal of the family Mustelidae. It is also known as the short-tailed weasel and the ermine. Natural history The stoat can be found almost everywhere throughout the northern temperate, subarctic and Arctic regions, of Europe, Asia, Canada and the United States. It was introduced into New Zealand in an unsuccessful attempt to control the rabbit population and is considered a serious pest because it eats the eggs and young of native birds. It is also regarded as a major predator of adult female endemic birds that nest in cavities such as holes in trees. The stoat is considered to be the prime cause of the decline and/or extinction of a number of endemic New Zealand bird species. Stoats are largely nocturnal or crepuscular but will sometimes come out during the day. Physical description The stoat is a member of the family