The Mountain Hare (Lepus timidus) (also known as the Blue Hare), is a hare, which is largely adapted to polar and mountainous habitats. It is distributed from Fennoscandia to eastern Siberia; in addition there are isolated populations in the Alps, Ireland, Poland, the United Kingdom and Hokkaidō. It has also been introduced to Shetland and the Faroe Islands. The Mountain Hare grows to a length of 46–65 centimetres (18–26 in) and a mass of 2–3 kilograms (4.4–6.6 lb), females being slightly heavier than males.
In Summer, for all populations of mountain hares, the coat is various shades of brown. In preparation for winter most populations moult into a white (or largely white) pelage. The tail remains completely white all year round, distinguishing the Mountain Hare from the Brown Hare, which has a black upper side to the tail.
Studies have shown that the diet of the Mountain Hare varies from region to region. It seems to be somewhat dependent on the particular habitat that the population under study lives in. For example, in northern Scandinavia where snow may blanket the ground for many months, the hares may graze on twigs and bark. In areas where snowfall is rare, such as Ireland, grass may form the bulk of the diet. Given a choice, Mountain Hares in Scotland and Ireland seem to prefer feeding on grasses.