The Mountain hare is a large species of hair that is largely adapted to polar and mountainous habitats. In summer, for all populations of mountain hares, the coat is various shades of brown. In preparation for winter, most populations molt into a white (or largely white) pelage but their tail remains completely white all year round. In Ireland, the Irish mountain hare stays brown all year and individuals rarely develop a white coat. They may also have a "golden" variation, particularly those found on Rathlin Island.
Mountain hares are distributed from Fennoscandia to eastern Siberia; in addition, there are isolated mountain populations in the Alps, Scotland, the Baltics, northeastern Poland, and Hokkaidō. They live in the tundra, taiga, forests in mountain areas, and in some regions in the woodlands of the open steppe. Populations in Ireland live on lowland pastures, coastal grasslands, moors, and salt marshes, not just in the mountains.
Mountain hares are nocturnal animals. During the day they rest in depressions, called forms that are dug in the snow or ground and at night they come out to feed. During the breeding season, they typically use abandoned burrows or dig their own to raise their young. Mountain hares are social and during cold snowy days, they often gather in groups to shelter or to feed together. They are always cautious and when they sense danger or disturbed they will flee, often in a zigzag pattern.
Mountain hares breed from January to September and females may produce between 1 and 3 litters per year consisting of 1-4 leverets. Gestation usually takes 50-54 days. The young are born fully furred and with their eyes open. They are nursed by the mother only in the evening and are weaned at the age of 4 weeks.
Mountain hares are not considered endangered at present, however, populations may decline locally due to changes in climate, starvation, habitat loss, hunting, and predation.
According to IUCN, the Mountain hare is common throughout its range but no overall population estimate is available. Currently, this species is classified as Least Concern (LC) on the IUCN Red List and its numbers today are stable.