Weasel – Mustela nivalis
Size: Males 19.4-21.7cm; females 17.3-18.3cm. Tail: males 4.2-5.2cm; females 3.4-4.3cm.
Fur ginger to russet brown, cream underside, irregular line between the two colours. Weasel does not change colour in winter. Long slender body, short tail with no black tip. Body length of 17-22cm and tail length 3-6cm. Weasel is smaller than stoat.
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Footprints: Weasels are carnivores and are therefore five-toed (width 1cm, length 1.3cm). They have the smallest footprints of all carnivores, their small size may be their most distinguishing feature.
Droppings: Droppings are deposited singly and often contain bits of bone and hair. They are narrow with twisty ends, as with all carnivore droppings. They are shorter and thinner than stoat droppings (3-6cm long, 0.2cm thick).
Stoat (Mustela erminea)
Larger than weasel (weasel head can fit through a wedding ring, whereas an adult stoat head cannot). Stoat tail has a black tip, whereas the weasel’s tail is shorter and does not have a black tip: it is all the same colour (ginger to russet brown). Stoat has a neat straighter line between the top and underside colours (with creamy underside) whilst the weasel has an irregular wavy line between the top and underside colours (with usually more of a white underside that can have specks of colour on it. These specks would not usually be present on a stoat). Stoat may become all white in winter (ermine), but black tail tip would still remain. Weasel will never turn completely white.