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.