Mustela nivalis
The least weasel is the smallest member of the family Mustelidae. Its body length is about 10-25 cm and its weight is 30-250 g. The males are usually larger than the females. The fur colour varies geographically. In Greece we can see that the dorsal part of the body is brown and the ventral part is white. The northern subspecies change colour in winter, becoming white in the whole.
The diet of Mustela nivalis includes mainly small rodents, but also small birds and hare. The hare usually is ten times larger than the weasel, so it is a very difficult target that can be reached only by big males. They kill their prey with a small bite in the occipital region dislocating the cervical vertebrae.
They mate in April-July and the birth takes place about 35 days later. The juveniles reach sexual maturity in 3-4 months.
According to the IUCN the least weasel is categorised as Least Concern (2016).
The least weasel is a very distinctive species that can be identified easily. It is a small carnivore (10-25 cm body length) and the only species that resembles to is the other member of the genus Mustela in Greece, European polecat (Mustela putorius). The difference of these species is on their colour. The fur of the least weasel is dorsally brown (variable) and ventrally pure white. The European polecat is mainly or partially black dorsally and ventrally.
We can recognise 18 subspecies, that belong to 3 major categories:
pygmaea-rixosa group (tiny, short tails, pedomorphic skulls, white pelts in winter), boccamela group (very large, large skulls, long tails, lighter coloured pelts) and nivalis group (medium length, transitional form). In Greece we can see the subspecies Mustela nivalis boccamela, that belongs to the second group.
Geographical distribution (worldwide)
The least weasel is a species with very wide distribution in the north hemisphere. It can be seen in North America (Canada and U.S.A.), in every country in Europe (with some exceptions as Ireland or Sicily), in the whole north Asia (north of Himalaya) and in a small northwest part of Africa (Morocco and Algeria).
Geographical distribution (Greece)
In Greece we can find the least weasel in every part of the mainland. There are some evidence that it exists in Crete and Rhodos.