The weasel (Mustela nivalis) is the UK’s smallest carnivore, able to put its head through the average wedding ring. The animal’s agility, speed and ability to escape from tight corners has given the language a range of insults – a weasel is a “deceitful and treacherous person”, then there are weasel words or being weasel faced. This is a slander on the species because while these animals are not exactly cuddly, they are attractive, long and slender. Even including a short tail they rarely measure more than 25cm.
Weasels are quick and relentless hunters of small rodents, particularly mice and voles. They are small and thin enough to enter mouse holes and frequently take them over as a den and breeding place. Weasels are said to be fairly common over mainland Britain in almost any habitat from urban gardens to mountainsides.
Since they are rarely seen or studied it is hard to estimate numbers. They are not protected and they do not hibernate so have to keep hunting to stay alive. Numbers can drop dramatically in the winter if mice are in short supply. They do not have the black tip to the tale of their cousin, the stoat. Their small size is the most distinctive feature for identification plus the speed at which they disappear.
