Also known as the “blue hare”, “tundra hare” or “Irish hare”, the Mountain hare is a relatively small-bodied member of the Lagomorpha order and the only lagomorph native to the UK. Its scientific name is derived from the Latin meaning “fearful hare”. Several subspecies proposed, based largely on size, including those in Scotland (L. timidus scoticus) being distinct from those in Ireland (L. t. hibernicus) and the “type species” first described from Scandinavia (L. t. timidus) in 1758.
That which follows is a summary of Mountain hare natural history. The detailed article for this species will follow in due course.
The Mountain hare at a glance
Size & Appearance: Range from 46-61cm (18-24 in.) head-body length with 4-8cm (1.5-3 in.) tail. Long hind feet growing 12-17cm (5-7 in.). Ears smaller than those of brown hare; 6-8cm (2.4-3 in.). Adult weight range 2-6kg (4.4-13 lbs.), typically 2.5-3.5kg (8 lbs); females ~10% heavier than males. On average, Scandinavian subspecies largest, then Irish, with Scottish subspecies smallest – some overlap. Grey-black coat during summer, white or part-white in winter; dusky blue underfur shows through on flanks. White tail without black markings (cf. brown hare). Moult Oct-Dec and Feb-May, females start first.
Distribution & habitat: Globally distributed in tundra and boreal habitats at all altitudes around the north pole. In the UK&I, it’s widespread throughout Ireland, but confined to uplands of mainland Scotland (mainly the Highlands); small English population in Peak District. Introduced to islands including Shetland, Hoy, Lewis, Harris, Skye, Raasay, Scalpay, Jura and Isle of Man. Primarily an animal of open heather moorlands at all altitudes, although occupies lowland agricultural areas, meadowland and grassland in Ireland. Will use non-conifer forestry plantations, particularly during inclement weather.
Longevity/Mortality: Heavy mortality during first year, particularly late summer and autumn, but may reach 8 or 9 in the wild; typically, 5 or 6. Oldest on record was female kept in captivity in Tokyo that reached 11 yrs. Many adults killed in driven shoots by gamekeepers Jan-May aimed at protecting grouse – human impact probably most significant source of mortality. Predators include foxes, wildcats, stoats and golden eagles; foxes may impact at population scale. Sea eagles, buzzards and harriers observed taking leverets and some are killed by domestic dogs and cats.
Sexing: Testes descended December-May, which may help separating sexes at close range. Males have broader and squarer head cf. females; sexes otherwise difficult to separate at distance.
Activity: Primarily nocturnal, found resting in forms during day. Peak of activity at dawn/dusk, particularly during summer. Boxing may be seen during day in spring. Most feeding happens at night.
Territory/Range: Non-territorial. Range highly variable with sex, season and habitat, although males consistently range over larger area cf. females, moving furthest during the breeding season. Males known to range over ~110ha in mixed upland habitat; females 85-90ha. High quality habitats (e.g. improved pasture) may reduce range to <10ha. Range often long and narrow as change altitude, particularly moving uphill during summer.
Diet: Herbivorous with heather dominating (up to 90%) in Scotland and graminoids (grasses/sedges/rushes) elsewhere. Bark, twigs, gorse, legumes and occasionally crops also taken. Lactating females may switch from heather (high phenol content reduces digestive efficiency) to graminoids. Produce two pellets types, like all rabbits and hares (refection): unformed mucosal pellets eaten directly from anus and smaller dry, hard pellets not re-eaten.
Reproduction: Breeding season runs January to June with 50 day gestation resulting in litter of 1-4 leverets (young); max. 8. In productive habitats females may produce multiple (up to 3) litters per year. Late and early conception results in young born between January and October. Young born fully furred with eyes open and left alone for first week after birth while mother feeds. Milk rich and female typically nurses one hour post-sunset. Leverets grow fast and weaned at three weeks; sexually mature in second year. Courtship involves several males pursuing female, with females “boxing” males to rebuke their advances. Some records of sterile brown x mountain hybrids, but cross-breeding appears rare.
Behaviour & Sociality: May gather in groups to feed, size varying with season; 100 or more counted at Aldergrove Airport, Belfast up to late 1960s, but 20 more common. Females appear dominant to males in all seasons. Well-developed sense of smell; will test and scent-mark vegetation and rocks. Clocked running at 64kmph (40 mph). Swims well and runs in wide arc, cf. zig-zagging of brown hare. Typically rests among rock and rock crevices; occasionally digs own form. Screams when injured or fearful; whistles or hisses when startled.
Threats: Widely persecuted by game keepers for eating heather intended for grouse and as possible route for transmission of louping ill (encephalomyelitis) in grouse, a viral disease spread by ticks. Listed on Annexe V of EC 1992 Habitats Directive (EC 92/43EEC), which restricts methods of capture. More protection offered in Ireland under Irish Wildlife Act (1976) and Northern Ireland under Special Protection Order (2004). Hunting Act (2004) in UK prohibits coursing (chasing with dogs), although this remains a popular pursuit in some areas. UK population may be ca. 400,000: 350,000 in Scotland and declining, worst in west; 10,000 in England; 40,000 in Ireland (perhaps almost 100,000?).
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Pelagic Publishing -- 2020 -- ISBN: 978-1784272043
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The natural history "bible" covering all British mammals with detailed coverage of their biology, behaviour, ecology and taxonomy written by experts in the field and referenced to the primary literature.
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