This animal resembles closely a weasel but it is much bigger. In winter the ermine is of white color with black tag. The body length of male species is 18-32 cm, their weight is 250 gram while the female species are smaller and lighter. The animal is active in twilight and night and sometimes in daytime. The ermine usual walking distance during winter day is about 3 km, the maximum distance is 10 km.

The animal swims well and is able to climb bushes and trees. It is very agile and moves in jumps; sometimes the ermine makes its way under snow.

The ermine’s common food is small and medium sized rodents (voles, mice, lemmings, water rats, mouse hares), frogs, lizards, fish as well as small birds and insects. The animal also scavenges and eats various berries.

It is very common in Eurasia and Siberia. The ermine is an important hunting species in northern Russia. The only place it is absent in is Severnaya Zemlya, and it is very rare in northern islands neighboring the mainland as well as in arctic deserts and northern tundra. The ermine is more common in southern tundra with its abundance of bushes, it is also often can be found in river valleys and lake beds.

The animal lives in northern taiga in the north of the Krasnoyarsk Territory and in the steppes and mountain taiga – in the south of the Krasnoyarsk Territory.

There is wide range of the ermine’s habitats with stronger attraction to semi-aquatic biotopes. The animal likes to live in meadows, farmlands, burnt areas and cut-over lands.

The animal does not make burrows; it uses for living natural cavities under the roots, chimneys in rocks, low-positioned hollows in tree trunks. The ermine often occupies the burrows of its victims which it lines with dry grass, leaves and wool. The coupling takes place in spring and early summer. The gestation period is 9-10 months with offspring appearing in April and May (2-18 cubs, usually 4-8 cubs). The animal casts its coat in spring and autumn. The population is exposed to various periodic fluctuations.