The stoat (Mustela erminea), also known as the short-tailed weasel, is a mammal of the genus Mustela of the family Mustelidae native to Eurasia and North America, distinguished from the least weasel by its larger size and longer tail with a prominent black tip. The name ermine is often, but not always, used for the animal in its pure white winter coat, or the fur thereof. In the late 19th century, stoats were introduced into New Zealand to control rabbits, where the stoats have had a devastating effect on native bird populations.