Lepus othus Merriam 1900

58.

Alaskan Hare

Lepus othus

French: Lievre d / Alaska / German: Alaska-Hase / Spanish: Liebre de Alaska

Other common names: Alaska Arctic Hare, Alaska Peninsula Hare, Alaska Tundra Hare, St. Michael's Hare, Tundra Hare, Swift Hare

Taxonomy. Lepus othus Merriam, 1900,

“St. Michaels, [Norton Sound], Alaska,” USA.

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 evidence is 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. othus is not clear and might be either in the Bering Strait or in the Kolyma region, Russia. Recent molecular phylogenetic study suggests that the break occurs in the Bering Strait, but more studies are required for a conclusive demarcation because the study was only based on mtDNA. If the distribution includes eastern Siberian tschuktschorum it has priority over othus. Recent molecular phylogenetic studies suggest that the eastern Siberian population is more closely related to L. timidus, and L. othus is distinct from L. arcticus, but more studies are required for a conclusive distinction because the study was only based on mtDNA. Morphological studies found that L. othusis closer to L. townsendii than to other northern species of Lepus. Lepus othusis partially sympatric with L. americanus in Alaska. As taxonomists are still trying to clarify the species differentiation in Lepus, the subspecific taxonomy is not elaborated yet. The original descriptions of the subspecies are often not very helpful as they are mostly based on few exterior characteristics and small numbers of individuals. It has been shown that the variability is clinal in more careful investigations. Hence, the distinction in subspecies might be arbitrary and unreasonable. Three subspecies recognized.

Subspecies and Distribution.

L. o. othusMerriam, 1900 — WAlaska (USA).

L. o. poadromusMerriam, 1900 — AlaskaPeninsula (USA).

L. o. tschuktschorum Nordqvist, 1883 — Chukchi Peninsula, NE Siberia (Russia).

Descriptive notes. Head-body 570-620 mm, tail 65-83 mm, ear 90-91 mm, hindfoot 164-179 mm; weight 3.9-4.8 kg. The Alaskan Hare is large. Winter pelage is white, except for black ear tips. In summer, fur on nose, sides of face, and top of head is cinnamon-buff; top of head appears darker. General color of back is drab cinnamon. Ears are similar in color to head on anterior one-half of outer surface, but posterior one-half is white. Frontlegs are white, with wash of cinnamon-buff; hindlegs are white, washed with brown. Molting occurs twice per year and starts in mid-September and early May. The Alaskan Hare has stout claws adapted to digging through hard-crusted snow to reach vegetation.

Habitat. Tundra of coastal regions of Alaska from sea level to elevations over 600 m. The Alaskan Hare occurs almost completely outside the limit of spruce (Picea, Pinaceae) forests. It lives in dense alder (Alnus, Butalaceae) thickets. Near the Kashunuk River, it was found in all habitats from sedge (Carex, Cyperaceae) flats and wet meadows to upperslopes of the Askinuk Mountains with vegetation dominated by sedge; lyme grass (Elymus arenarius, Poaceae); Potentilla egedei (Rosaceae); Poa eminens (Poaceae); crowberry (Empetrum nigrum, Ericaceae); willow (Salix, Salicaceae); Ledum decumbens/ Rhododendron subarcticum (Ericaceae); dwarf birch (Betula nana) and green alder (Al nus crispa), both Betulaceae; ferns (Dryopteris); and lichens. Northern populations of Alaskan Hares primarily live in tundra or alluvial plains, and southern populations primarily live in coastal lowlands.

Food and Feeding. Diet of the Alaskan Hare in April/May consists mainly of shrubs. Woody parts of the Alaskan willow (S. alaxensis) and leaves of crowberry are most commonly eaten. In spring, they fed at edges of melting snow patches where crowberries from the previous summer were abundant. One captive Alaskan Hare seldom drank water.

Breeding. Mating season of the Alaskan Hare occurs in mid-April and May, and gestation is ¢.46 days. Parturition occurs in late May and early June and seems to coincide with loss of snow cover in late May. Females have one litter per year, with 5-7 young (average 6-3 young). Precocial young are born in a nest aboveground in thick shelter of willow or alder. Nests are mere depressions in the vegetation and have no lining. Young have brownish buff upper parts and white under parts. Nose, eye rings, and feet are buff. Ear tips are black, and tail is white. Female Alaskan Hares nurse 5-9 weeks—a prolonged nursing period probably enhances survival of young and perpetuates rapid growth. A few weeks after birth, young begin to drift away from their mother. Rapid growth allows young to reach minimum adult body mass during the short summer; young are fully grown by late September. Initial rate of growth of the Alaskan Hare is greater than that of the Snowshoe Hare (L. americanus), the Black-tailed Jackrabbit (L. californicus), and the White-tailed Jackrabbit (L. townsendi).

Activity patterns. Alaskan Hares leave dense thickets in the evening to feed.

Movements, Home range and Social organization. Alaskan Hares live alone, except during mating when groups of 20 or more are observed. If they still have their winter pelage in May, they remain near snowfields at high elevations. One captive Alaska Hare never attempted to seek shelter during snow and rain.

Status and Conservation. Classified as Least Concern on The IUCN Red List. Populations of Alaskan Hares seem to be widespread and stable, although little monitoring occurs. Native people modestly harvest Alaskan Hares for food and fur. Southern populations might be subject to habitat loss and climate change, although the latter is speculative. Research is needed to assess taxonomic status of the Alaskan Hare relative to the Mountain Hare (L. timidus) and the Arctic Hare (L. arcticus) and evaluate habitat use and population status and trends.

Bibliography. Anderson (1974), Anderson & Lent (1977), Angermann (2016), Baker et al. (1983), Ben Slimen, Suchentrunk & Ben Ammar Elgaaied (2008), Best & Henry (1994b), Bittner & Rongstad (1982), Dufresne (1946), Flux (1983), Flux & Angermann (1990), Hall (1981), Hewson (1991), Hoffmann & Smith (2005), Howell (19364), Lissovsky (2016), Loukashkin (1943), Merriam (1900), Murie (1959), Murray & Smith (2008c), Nelson (1909), Schiller & Rausch (1956), Walkinshaw (1947), Waltari & Cook (2005), Waltari et al. (2004), Wu Chunhua et al. (2005).