A spotter’s guide to mustelids
Amy Lewis from The Wildlife Trust shares some top tips for finding the elusive members of the UK weasel family
Most striking and recognisable if seen at night, the badger is the UK’s largest mustelid. You will often see the shallow scrapings they make in grassy areas near woods as they dig for earthworms, insect larvae and roots. Several large holes in woodland banks with track ways leading away and through gaps in undergrowth signal a sett where family groups live together underground. Look for piles of grass at entrances to identify an active one.
Active: At dusk, especially in summer
Stoats and weasels can be difficult to tell apart if seen in isolation. However, stoats are the larger and have a black tip to their longer tail. Some individuals also turn white in winter to camouflage themselves in snow-covered landscapes, when they are known as ermine. Stoat droppings are dark, elongated, coiled and twisted with fur and feathers, like mini dreadlocks. They are most often found in large piles near their den area.
Best seen: In spring when they are more active feeding young
Our smallest mustelid is also one of our most voracious predators. At just 23cm long, the weasel’s compact size and body shape allows it to hunt small mammals in their burrows. Rather than the stoat’s bounding, energetic gait, weasels run quickly and close to the ground. They use the cover of hedgerows and field margins to range across their territories and the remains of small birds and mammals near little holes and crevices can indicate they are around.
Best seen: Before spring growth provides shelter
Large rounded paw prints in the mud under a bridge, with a hint of webbing between the toes, are a good sign of otters being around, as are piles of fish bones left on a flat stone. Otters eat every scrap of flesh and leave the spine, bony parts of the skull and the skin rolled back towards the tail. Otter poo, known as ‘spraint’, is used as a territorial marker so look for piles of digested fish scales and small bones near rivers on tree stumps and fallen logs, boulders and around the foundations of a bridge.
Best seen: At dawn and dusk on rivers and canals in lowland Britain
These mustelids are at home in the trees where their flexible bodies, strong claws and long tails allow them to search for berries, bird eggs, fungi, invertebrates and small mammals. They will also nest in a hole high up in a tree. Like otters, martens use their dropping to mark territory so they place them in prominent places along forest paths. They are twisted like a spring and smell faintly of fruit. Tracking them is hard, but they can be tempted to a hide with peanut butter and jam sandwiches.
Best seen: At night in a Scottish forest; occasionally in daylight if feeding kits
The polecat has a two-toned coat, with thick, dark guard hairs overlaying much lighter under fur. The characteristic pale eyebrows, ear tips and muzzle also give it a masked, bandit-like appearance. Ferrets are their domesticated descendents so they share many characteristics. These secretive mammals are notoriously difficult to spot because they have become so rare in the UK, although they are very gradually increasing. They often hunt along hedgerows and woodland margins and are drawn to road kill so keep an eye on the verges at night.
Best seen: At night in central and northwest England and parts of Scotland