Weasels have a bad press. Their name has come to mean some sly, sneaky and treacherous. Their most prominent depiction in popular fiction is (together with stoats) as a gang of vicious, mean ruffians, taking advantage of poor Mr Toad’s foolishness to take over Toad Hall.
With their pointy teeth and carnivorous diet, they are certainly fearsome predators, but I think their reputation is rather unfair. If they were bigger, perhaps people would respect them more. The larger members of the mustelid family (badgers and otters) are (generally) regarded with affection. Compare how they’re portrayed in The Wind in the Willows with the poor stoats and weasels. Yet otters are no gentler than weasels.
While weasels are pretty common in the UK, and active both day and night, people are largely unaware of them. I remember being amazed how small they are, the first time I saw one. In fact, a sub-type of the common weasel is the smallest carnivore on earth. The type we get here in the UK measures just 18cm (females) or 22cm (males) in length, and weighs just 70g (females) or 125g (males).
Despite their diminutive size, weasels are effective hunters. Their diet is largely made up of small rodents (voles and mice), but they can also dispatch rabbits. A weasel can run carrying prey that weighs half their own body weight. Pretty impressive.
Last weekend I attended a fascinating course on smaller mustelids, run by the Wildwood Trust. Before now I’ve not spent much time thinking about small mustelids. I was amazed by how little we know about stoats and weasels, which are both pretty common and widespread. This lack of knowledge may partly be down to their poor reputation. The difficulties of surveying them doesn’t help, either.
The limited data we do have suggests that, while they are common, their numbers have been declining in recent decades. They’re not a protected species, so can be trapped and killed by gamekeepers. Secondary poisoning from eating poisoned rats is also a problem, along with predation by cats, foxes and birds of prey. They’re also vulnerable to parasites. Starvation is probably the biggest cause of death for weasels, and they are very dependent on the population of small rodents.
At least now, with the advent of cheaper DNA tests and camera traps, we may be able to find out a bit more about them. I’d certainly love to learn more, as they’re fascinating creatures.