The stoat (Mustela erminea), also known as the short-tailed weasel, is a species of 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. The stoats have had a devastating effect on native bird populations (see stoats in New Zealand).
It is classed by the IUCN as least concern, due to its wide circumpolar distribution, and because it does not face any significant threat to its survival. It was nominated as one of the world’s top 100 “worst invaders”.
Ermine luxury fur is often used by Catholic monarchs, pontiffs and cardinals, who sometimes use it as the mozetta cape. It is also used in capes on devotional images such as the Infant Jesus of Prague. The parliamentary and coronation robes of British peers of the realm are also made from ermine. source