Lepus timidus Linnaeus 1758

59. Mountain Hare Lepus timidus French: Liévre variable / German: Schneehase / Spanish: Liebre de montana Other common names: Blue Hare, Snow Hare, Eurasian Arctic Hare, Varying Hare, White Hare; Irish Hare (hibernicus), Alpine Mountain Hare (varronis) Taxonomy. Lepus timidus Linnaeus, 1758, “in Europa.” Formerly, the three arctic species, L. timidus, L. arcticus, and L. othus, were included in L. timidus based on morphological characteristics that, relative to their distributions, form a circumpolar “ring species.” This is also supported by genetic analysis of mtDNA, although evidence based only on mtDNA should be treated cautiously. There is also the view that two species exist: L. timidus in the Old World and L. arcticus in Greenland, northern Canada, Alaska, and the Chukchi Peninsula, Russia. Other lagomorph taxonomists consider that L. arcticus is conspecific with L. timidus and distinct from L. othus. Until conclusive evidenceis available, the three species are considered to be distinct with L. timidus in the Old World, L. othus in Alaska, and L. arcticus in northern Canada and Greenland. Nevertheless, the border between L. timidus and L. othusis not clear and might be either in the Bering Strait or in the Kolyma region, Russia. Recent molecular phylogenetic study suggests that the break occursin the Bering Strait, but more studies are required for a conclusive demarcation because the study was only based on mtDNA. Six populations of L. timidus are geographically separated and morphologically distinct and therefore can be treated as subspecies (abe, ainu, hibernicus, orii, scoticus, and varronis). Because division into subspecies is mostly based on pelage characteristics, it must be considered preliminary. Three studies analyzing geographic variation of metric characters of the skull of L. timidus demonstrated clinal variations. This doubts the advisability of identifying subspecies in L. timidus. Origin of subspecies of L. timidus in Europe from a panmictic population during the Weichsel period is supported by genetic assessments. Hybridization between L. timidus and L. europaeus and between L. timidus and L. tolai are recorded in contact zones. No interbreeding has been noted between scoticus and hibernicus on the island of Mull where both subspecies were introduced 60 years ago. Sixteen subspecies recognized. Subspecies and Distribution. L. t. timidus Linnaeus, 1758 — Scandinavia S to 59° N, N Russia (S to 57° N to 58° N) to E of Ural Mts, Estonia, perhaps Poland, and Altai and Beita Mts in N Xinjiang (China); from Sweden extending in hybrid zones with the subspecies sylvaticus to S coast of Norway and W Latvia. L. t. abet Kuroda, 1938 — Kurile Is (Russia). L. t. ainu Barrett-Hamilton, 1900 — Hokkaido (Japan). L. t. begitschevi Koljuschev, 1936 — Taimyr Peninsula (Russia). L. t. gichiganus J. A. Allen, 1903 — C Yakutia, Kamchatka and Okhotsk Sea coast (Russia). L. t. hibernicus Bell, 1837 — Ireland. L. t. kolymensis Ognev, 1922 — NE Siberia (Russia). L. t. kozhevnikovi Ognev, 1929 — C Russia from 57° to 58°N, whereit intergrades with the nomonotypical timidus S to 53° N. The W boundary is unclear. L. t. lugubris Kastschenko, 1899 — Siberian Altai Mts (Russia). L. t. mordeni Goodwin, 1933 — Russian Far East (Ussuri Valley and lower and middle Amur River) and Heilongjiang (China). L. t. ori Kuroda, 1928 — Sakhalin (Russia). L. t. scoticus Hilzheimer, 1906 — Scotland. L. t. sibiricorumJohansen, 1923 — W & SW Siberia (Russia), N Kazakhstan, and Tacheng Mts in N Xinjiang (China). L. t. sylvaticus Nilsson, 1831 —S Sweden, extending in hybrid zones with nominotypical timidus to S coast of Norway and W Latvia. L. t. transbaikalicus Ognev, 1929 — Trans-Baikal region in E Siberia (Russia) and E Inner Mongolia (= Nei Mongol, China). L. t. varronis Miller, 1901 — at high altitudes in the Alps, C Europe. The Mountain Hare inhabits the Palearctic from Scandinavia to Russian Far East, except E Chukchi Peninsula, S to Baltic States, E Poland, N Ukranie, and E to Tian Shan Mts, Altai Mts, N Mongolia, NW & NE China (N Xinjiang, N Inner Mongolia, Heilongjiang), and Sikhote-Alin Mts. There are isolated populations in Scotland, Ireland, the Alps, Sakhalin (Russia), Hokkaido (Japan), and the Kurile Is. The nominotypical subspecies has been introduced into Faroe Is (Denmark), Scottish Is, and parts of England. Introduced populations on Spitsbergen I failed to persist. Descriptive notes. Head-body 510-550 mm, tail 59-65 mm, ear 90-100 mm, hindfoot 159-165 mm; weight 2.4-3.4 kg (depending on subspecies). The smallest subspecies is the “Alpine Mountain Hare” (varronis), and the largest subspecies is the nominate timidus. Male Mountain Hares tend to be smaller than females. In general, northern populations are larger. The Mountain Hare is completely white in winter, and its head and body are brown in summer. Summer fur differs among populations and can be pale gray or dusky brown in mountainous areas to rich rustbrown on plains. Exceptionally, fur of the Irish Hare is white on rump, flanks, and legs, with its upper back and head remaining brown in winter. Ears are short and narrow, with 30mm black tips on exterior surfaces and 5mm on interior surfaces. Relatively large head has prominent eyes, with yellowish irises in adults but dark brown in young. Hindfeet have hairy soles and widely spreading toes. Molt occurs three times per year: white to brown in spring; brown to brown in late summer; and brown to white in autumn. Molt is initiated by daylength, and its duration is influenced by temperature. Mountain Hares at high elevations and latitudes remain white longer, relative to average ambient temperature and duration of snow cover. Habitat. Wide range of biomes from extreme tundra with permafrost in northern Russia to rich agricultural areas in Ireland. Mountain Hares prefer to live in forests of pine, birch, and juniper. In Scotland and Ireland, heather moors and bog land are favored, and in Russia, copses in the middle of open steppe and reed belts around lakes are selected. In the Alps, Mountain Hares prefer highly structured forests and thickets at forest edges. In spring, abundant herbaceous food in meadows is important to Mountain Hares. When a habitat offers food and shelter against predators, Mountain Hares use it for rest and activity. Forms are usually a depression they make. In snow, Mountain Hares burrow to make forms and enter rock crevices or marmot (Marmota) burrows for shelter or escape. They sometimes dig permanent burrows 1-2 m long in the ground. Mountain Hares in Ireland and the Alps do not burrow, but in Russia, complex burrows up to 7 m long have been reported. On agricultural land, Mountain Hares tends to be replaced by European Hares (L. europaeus) in Europe and Cape Hares (L. capensis) further east. Food and Feeding. Mountain Hares are grazers in summer and browsers in winter. Their diets vary with habitat. Plant species used as food in forest habitats include leaves and twigs of Salix and Populus (both Salicaceae), Sorbus (Rosaceae), Betula (Betulaceae), Juniperus (Cupressaceae), and Vaccinium (Ericaceae); on Scottish moorlands and Swedish islands, Calluna (Ericaceae) is eaten. Different grass species and clovers are eaten when available. With snow cover, Mountain Hares feed on twigs, bark, moss, and lichens. They seldom drink water but may eat snow. Re-ingestion ofsoft pellets takes place at 09:00-16:00 h and increases dietary digestibility up to 25%; these pellets contain three times as much protein as regular pellets. Mountain Hares feed with their back to the wind and can clear snow from vegetation with their forepaws. When snow is hard, they move to lower ground to feed. Breeding. Gestation of the Mountain Hare lasts 46-55 days. Postpartum estrus with copulations a few hours after parturition is common. Superfetation does occur. Females have predominantly 2-3 litters/year, with litter sizes of 1-3 young, resulting in 5-9 offspring/female during a reproductive season. Weather has an important influence on numberof litters produced during a reproductive season. The second litter is on average larger than the first one. Start of breeding varies with temperature, and gestating females have been recorded from January/February until August/September. Juvenile females do not breed in the same year of their birth. Differences in reproduction exist among populations or subspecies. For example, subspecies timidus in northern Norway normally has only 1-2 litters/ year, but in south-western Sweden,it regularly has three litters. Another difference is the length of the reproductive period with the Irish Hare having a longer one than scoticus. At birth, young are fully furred, their eyes are open, and they start suckling immediately. Adult sex ratio is 1:1. Overall juvenile survival from birth to the following spring averages 20%. In January-July, male Mountain Hares often follow 2-20 m behind a female for hours. Males use scent to track females. During courtship, several males chase a female, but males do not guard females. Females dominate males and strike with their forepaws with ears laid backward if the male approaches too closely. Copulation can involve five or more males and a female, and males can be involved in long fights. Activity patterns. Mountain Hares are nocturnal throughout the year, with a prolonged resting phase during the day. Activity patterns change seasonally with circadian rhythms. Mountains Hares rest by day in a form, with ears back and eyes half closed, but they only sleep for a few minutes at a time. In summer when daylight increases and in winter when food is scarce, more Mountain Hares are active during the day. Activity is highest during the first two hours after sunset. Movements, Home range and Social organization. Mountain Hares move an average of 1400 m/mnight, but they can travel up to 2400 m/night. Home rangesizes vary depending on climate. Home ranges are ¢.200 ha in borea

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