The Siberian weasel (Mustela sibirica) is a medium-sized weasel native to Asia, where it is widely distributed and inhabits various forest habitats and open areas. It is therefore listed as Least Concern on the IUCN Red List. It is also known as kolonok or kolinsky.In form and hunting behaviour, the Siberian weasel represents a transitional form between small mustelids (such as stoats and least weasels) and their larger cousins (minks and polecats).