Weasel –Mustela nivalis


The weasel is the smallest member of the Mustelid family and Britain’s smallest carnivore. It is smaller than the stoat and has no black tip to its tail, although it does have small white patches under its chin and throat. It is widespread and common on mainland Britain but absent from Ireland. Like the stoat it is still persecuted by gamekeepers.

The weasel may travel up to 2.5 km on a hunting expedition. It climbs well and will often raid birds nests, taking the eggs and young. When ratting, its courage is even greater than the stoat’s. Female weasels are considerably smaller than males, but both are small enough to pursue rats, mice and even field voles in their own tunnels.

It is common in most habitats and frenetically active both day and night as it must consume a quarter to a third of its body weight every day to survive.

Origin: Native.
Size: Males 20 – 22 cm, plus short tail 6.5 cm. Females 15 – 18 cm, plus short tail 4.5 cm.
Description: Body and neck cylindrical and long, legs short. Brown on the back, white under-parts. Smaller than the stoat.
Habitat: Where there is suitable food they occur in a wide range of habitats from lowland forests to upland moors and even towns.
Young: Breed April – August, 1-2 litters a year, 4 – 6 young. The young of the first litter grow very fast and are able to kill at 8 weeks. They often accompany their mother on hunting expeditions. Unlike stoats, weasels have no delayed implantation.
Nest: Nest is made of grass and leaves, usually in holes in a wall, or tree stumps.
Diet: Mice and voles make up 60% – 80% of their diet, but also eat rats, frogs, birds and small rabbits.
Population: Pre-breeding season estimated to be 450,000 adults.