Index of Species Information

WILDLIFE SPECIES:  Lepus americanus


WILDLIFE SPECIES: Lepus americanus
AUTHORSHIP AND CITATION : Sullivan, Janet. 1995. Lepus americanus. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: []. Revisions: 18 July 2013: DeGraaf, Richard M.; Rudis, Deborah D. 2001 citation corrected to DeGraaf, Richard M.; Yamasaki, Mariko. 2001. ABBREVIATION : LEAM COMMON NAMES : snowshoe hare varying hare snowshoe rabbit TAXONOMY : The currently accepted scientific name of the snowshoe hare is Lepus americanus Erxleben [18]. Accepted subspecies include [18,38]: Lepus americanus americanus Erxleben L. a. cascadensis Nelson L. a. columbiensis Rhoads L. a. dalli Merriam L. a. klamathensis Merriam L. a. oregonus Orr L. a. pallidus Cowan L. a. phaeonotus J. A. Allen L. a. pineus Dalquest L. a. seclusus Baker and Hankins L. a. struthopus Bangs L. s. tahoensis Orr L. a. virginianus Harlan L. a. washingtonii Baird. ORDER : Lagomorpha CLASS : Mammal FEDERAL LEGAL STATUS : None [84] OTHER STATUS : Information on state- and province-level protection status of animals in the United States and Canada is available at NatureServe, although recent changes in status may not be included.


WILDLIFE SPECIES: Lepus americanus
GENERAL DISTRIBUTION : Snowshoe hares occur from Newfoundland east to western Alaska; south in the Sierra Nevada to central California; in the Rocky Mountains to southern Utah and northern New Mexico; and in the Appalachian Mountains to North Carolina and Tennessee [9,18,20,38]. Locations of subspecies are as follows [38]: Lepus americanus americanus - Ontario, Manitoba, Saskatchewan, Alberta,   Montana, and North Dakota L. a. cascadensis - British Columbia and Washington L. a. columbiensis - British Columbia, Alberta, and Washington L. a.  dalli - Mackenzie District, British Columbia, Alaska, Yukon   Territory L. a. klamathensis - Oregon and California L. a. oregonus - Oregon L. a. pallidus - British Columbia L. a. phaeonotus - Ontario, Manitoba, Saskatchewan, Michigan, Wisconsin, and   Minnesota L. a. pineus - British Columbia, Idaho, and Washington L. a. seclusus - Wyoming L. a. struthopus - Newfoundland, Nova Scotia, New Brunswick, Prince Edward   Island, Quebec, and Maine L. a. tahoensis - California, western Nevada L. a. virginianus - Ontario, Quebec, Maine, New Hampshire, Vermont,   Massachusetts, Pennsylvania, Ohio, and Tennessee L. a. washingtonii - British Columbia, Washington, and Oregon ECOSYSTEMS : FRES10 White-red-jack pine FRES11 Spruce-fir FRES18 Maple-beech-birch FRES19 Aspen-birch FRES20 Douglas-fir FRES21 Ponderosa pine FRES22 Western white pine FRES23 Fir-spruce FRES24 Hemlock-Sitka spruce FRES25 Larch FRES26 Lodgepole pine FRES27 Redwood FRES28 Western hardwoods STATES :
BLM PHYSIOGRAPHIC REGIONS :     1  Northern Pacific Border     2  Cascade Mountains     4  Sierra Mountains     5  Columbia Plateau     8  Northern Rocky Mountains     9  Middle Rocky Mountains    10  Wyoming Basin    11  Southern Rocky Mountains    12  Colorado Plateau    15  Black Hills Uplift    16  Upper Missouri Basin and Broken Lands KUCHLER PLANT ASSOCIATIONS :    K001  Spruce-cedar-hemlock forest    K002  Cedar-hemlock-Douglas-fir forest    K003  Silver fir-Douglas-fir forest    K004  Fir-hemlock forest    K008  Lodgepole pine-subalpine forest    K012  Douglas-fir forest    K015  Western spruce-fir forest    K015  Western spruce-fir forest    K014  Grand fir-Douglas-fir forest    K020  Spruce-fir-Douglas-fir forest    K022  Great Basin pine forest    K028  Mosaic of K002 and K026    K093  Great Lakes spruce-fir forest    K094  Conifer bog    K095  Great Lakes pine forest    K096  Northeastern spruce-fir forest    K097  Southeastern spruce-fir forest    K099  Maple-basswood forest    K102  Beech-maple forest    K013  Cedar-hemlock-pine forest    K016  Eastern ponderosa forest    K017  Black Hills pine forest    K018  Pine-Douglas-fir forest SAF COVER TYPES :      1  Jack pine      5  Balsam fir     12  Black spruce     13  Black spruce-tamarack     15  Red pine     16  Aspen     17  Pin cherry     18  Paper birch     19  Gray birch-red maple     20  White pine-northern red oak-red maple     21  Eastern white pine     22  White pine-hemlock     23  Eastern hemlock     24  Hemlock-yellow birch     25  Sugar maple-beech-yellow birch     30  Red spruce-yellow birch     31  Red spruce-sugar maple-beech     32  Red spruce     33  Red spruce-balsam fir     34  Red spruce-Fraser fir     35  Paper birch-red spruce-balsam fir     37  Northern white-cedar     38  Tamarack     51  White pine-chestnut oak    107  White spruce    201  White spruce    202  White spruce-paper birch    204  Black spruce    205  Mountain hemlock    206  Engelmann spruce-subalpine fir    207  Red fir    208  Whitebark pine    209  Bristlecone pine    210  Interior Douglas-fir    212  Western larch    216  Blue spruce    218  Lodgepole pine    219  Limber pine    217  Aspen    221  Red alder    223  Sitka spruce    224  Western hemlock    225  Western hemlock-Sitka spruce    226  Coastal true fir-hemlock    227  Western redcedar-western hemlock    228  Western redcedar    229  Pacific Douglas-fir    230  Douglas-fir-western hemlock    231  Port-Orford-cedar    243  Sierra Nevada mixed conifer    251  White spruce-aspen    253  Black spruce-white spruce    254  Black spruce-paper birch    252  Paper birch    256  California mixed subalpine SRM (RANGELAND) COVER TYPES :    203  Riparian woodland    409  Tall forb    411  Aspen woodland    421  Chokecherry-serviceberry-rose PLANT COMMUNITIES : Snowshoe hares are primarily found in boreal forests and upper montane forests; within these forests they favor habitats with a dense shrub layer.  In the Pacific Northwest snowshoe hares occupy diverse habitats including mature conifers (mostly Douglas-fir [Pseudotsuga menziesii] and variants), immature conifers, alder (Alnus spp.)/salmonberry (Rubus spectabilis), Sitka spruce (Picea sitchensis)/salal (Gaultheria shallon), and cedar (Thuja spp.) swamps [53].  In western Oregon snowshoe hares were present in brush patches of vine maple (Acer circinatum), willows (Salix spp.), rhododendrons (Rhododendron spp.), and other shrubs [2]. In Utah snowshoe hares used Gambel oak (Quercus gambelli) in the northern portion of the Gambel oak range [39]. In the Southwest the southernmost populations of snowshoe hares occur in the Sangre de Cristo Mountains, New Mexico, in subalpine scrub:  narrow bands of shrubby and prostrate conifers at and just below timberline that is usually composed of Engelmann spruce (Picea engelmannii), bristlecone pine (Pinus aristata), limber pine (P. flexilis), and/or common juniper (Juniperus communis) [12]. In Minnesota snowshoe hares use jack pine (P. banksiana) uplands, edges, tamarack (Larix laricina) bogs, black spruce (Picea mariana) bogs, and sedge (Carex spp.), alder, and scrub fens [62]. In New England snowshoe hares favor second-growth aspen (Populus spp.)-birch (Betula spp.) near conifers, but other forest types occupied by snowshoe hares include aspens, paper birch (B. papyrifera), northern hardwoods, red maple (A. rubrum), balsam fir (Abies balsamea), red spruce (Picea rubens)-balsam fir, eastern hemlock (Tsuga canadensis), northern red oak (Quercus rubra), oak (Quercus spp.)-pine (Pinus spp.), eastern white pine (P. strobus)-northern red oak-red maple, and eastern white pine.  Snowshoe hares also use shrub swamps dominated by buttonbush (Cephalanthus occidentalis), alders, and silky dogwood (Cornus ammomum) [20,21].  Further details on plant communities used by snowshoe hares in different regions are in Bittner and Rongstad [9].


WILDLIFE SPECIES: Lepus americanus
TIMING OF MAJOR LIFE HISTORY EVENTS : Diurnal Activity:  Snowshoe hares are crepuscular to nocturnal.  They are shy and secretive and spend most of the day in shallow depressions, called forms, scraped out under clumps of ferns, brush thickets, and downed piles of timber.  They occasionally use the large burrows of mountain beavers (Aplodontia rufa) as forms.  Diurnal activity level increases during the breeding season.  Juveniles are usually more active and less cautious than adults [53]. Breeding Season:  Snowshoe hares are active year-round.  The breeding season for hares is stimulated by new vegetation and varies with latitude, location, and yearly events (such as weather conditions and phase of showshoe hare population cycle) [9,35].  Breeding generally begins in late December to January and lasts until July or August [35,53].  In northwestern Oregon male peak breeding activity (as determined by testes weight) occurs in May and is at the minimum in November.  In Ontario the peak is in May and in Newfoundland the peak is in June.  Female estrus begins in March in Newfoundland, Alberta, and Maine, and in early April in Michigan and Colorado.  First litters of the year are born from mid-April to May [9]. Gestation and Litter Size:  The gestation period is 35 to 40 days; most studies report 37days as the average length of gestation.  Litters average three to five leverets depending on latitude, elevation, and phase of population cycle, ranging from one to seven [9,53].  Deep snowpack increases the amount of upper-branch browse available to snowshoe hares in winter and therefore has a positive relationship with the nutritional status of breeding adults.  Litters are usually smaller in the southern sections of snowshoe hare range since there is less snow.  Newborn snowshoe hares are fully furred, open-eyed, and mobile. They leave the natal form within a short time after birth, often within 24 hours.  After leaving the birthplace siblings stay near each other during the day, gathering once each evening to nurse [9,53].  Weaning occurs at 25 to 28 days except for the last litter of the season which may nurse for 2 months or longer [64]. Pregnancy Rate and Productivity:  Female snowshoe hares can become pregnant anytime after the 35th day of gestation.  The second litter can therefore be conceived before the first litter is born (snowshoe hares have twin uteri) [9].  Pregnancy rates ranged from 78 to 100 percent for females during the period of first litter production, 82 to 100 percent for second litters, and for the periods of third and fourth litters pregnancy rates vary with population cycle [17].  In Newfoundland the average number of litters per female per year ranged from 2.9 to 3.5, and in Alberta the range was from 2.7 to 3.3 [9].  The number of litters per year varies with phase of population cycle (see below).  In Alberta the average number of litters per year was almost 3 just after a population peak and 4 just after the population low [17].  Females normally first breed as 1-year-olds.  Juvenile breeding is rare and has only been observed in females from the first litter of the year and only in years immediately following a low point in the population cycle [9]. Mortality:  In Yukon Territory 30-day survival of radio-tagged leverets was 46 percent, 15 percent, and 43 percent for the first, second, and third litter of the year, respectively.  There were no differences in mortality in plots with food added.  The main proximate cause of mortality was predation by small mammals including red squirrels (Tamiasciurus hudsonicus) and arctic ground squirrels (Spermophilus parryii).  Littermates tended to live or die together more often than by chance.  Individual survival was negatively related to litter size and positively related to body size at birth.  Litter size is negatively correlated with body size at birth [57]. Population Cycles:  Northern populations of snowshoe hares undergo cycles that range from 7 to 17 years between population peaks.  The average time between peaks is approximately 10 years.  The period of abundance usually lasts for 2 to 5 years followed by a population decline to lower numbers or local scarcity.  Areas of great abundance tend to be scattered [36,53].  Populations do not peak simultaneously in all areas, although there is a great deal of synchronicity in northern latitudes [3].  From 1931 to 1948 the cycle was synchronized within 1 or 2 years over most of Canada and Alaska, despite differences in predators and food supplies [68].  In central Alberta low snowshoe hare density occurred in 1965 with 42 to 74 snowshoe hares per 100 acres (40 ha). The population peak occurred in November 1970 with 2,830 to 5,660 snowshoe hares per 100 acres (40 ha) [44].  In the southern parts of its range snowshoe hare populations do not fluctuate radically [46]. Exclosure experiments in Alberta indicated that browsing by snowshoe hares during population peaks has the greatest impact on palatable species, thus further reducing the amount of available foods.  In this study there was insufficient nutritious young browse available to sustain the number of snowshoe hares present in the peak years (1971 and 1972) in winter [61]. PREFERRED HABITAT : A habitat suitability index model for snowshoe hare was summarized by Carreker [16].  Major variables in habitat quality include average visual obstruction and browse biomass.  Snowshoe hares prefer young forests with abundant understories.  The presence of cover is the primary determinant of habitat quality for snowshoe hares and is more significant than food availability [16] or species composition [19,51]. Species composition does, however, influence population density; dense softwood understories support greater snowshoe hare density than hardwoods because of cover quality.  In Maine it was observed that female snowshoe hares were more common on sites with less cover but more nutritious forage; males tended to be found on sites with heavier cover [50]. Winter browse availability depends on height of understory brush and winter snow depth; 6- to 8-foot tall (1.8-2.4 m) saplings with narrow stem diameters are required for winter browse in heavy snow [81]. In northern regions snowshoe hares occupy conifer and mixed forests in all stages of succession, but early successional forests foster peak abundance.  Deciduous forests are usually occupied only in early stages of succession [36].  In New England snowshoe hares preferred second-growth deciduous, coniferous, and mixed woods with dense brushy understories; snowshoe hares appear to prefer shrubby old-field areas, early- to mid-successional burns, shrub-swamps, bogs, and upper montane krumholz vegetation [21].  In Maine snowshoe hares were more active in clearcut areas than in partially cut or uncut areas.  Sapling densities were highest on 12- to 15-year-old plots; these plots were used more than younger stands [55].  In northern Utah snowshoe hares occupied all the later stages of succession on quaking aspen and spruce-fir but were not observed in meadows [66].  In Alberta snowshoe hares use upland shrub-sapling stages of regenerating aspens (either postfire or postharvest) [82].  In British Columbia overstocked juvenile lodgepole pine (Pinus contorta) stands formed optimal snowshoe hare habitat [72]. In western Washington most unburned, burned, or scarified clearcuts will normally be fully occupied by snowshoe hares within 4 to 5 years as vegetation becomes dense [15].  In older stands (more than 25 years) stem density begins to decline and cover for snowshoe hares decreases [46].  However, in north-central Washington snowshoe hares may not colonize clearcuts until 6 or 7 years and it may take 20 to 25 years for snowshoe hare density to reach maximum [6].  Winter snowshoe hare pellet counts were highest in 20-year-old lodgepole pine stands, lower in older lodgepole stands, and lowest in spruce-dominated stands [46].  In western Oregon snowshoe hares were abundant only in early successional stages including stable brushfields [2].  In west-central Oregon an old-growth Douglas-fir forest was clearcut and monitored through 10 years of succession.  A few snowshoe hares were noted in adjacent virgin forest plots; they represented widely scattered, sparse populations. One snowshoe hare was observed on the disturbed plot 2.5 years after it had been clearcut and burned; at this stage ground cover was similar to that of the uncut forest.  By 9 years after disturbance snowshoe hare density had increased markedly [33]. Slope and Aspect:  In western Washington snowshoe hares routinely used steep slopes where cover was adequate; most studies, however, suggest that snowshoe hares tend to prefer gentle slopes [15]. Moonlight increases snowshoe hare vulnerability to predation, particularly in winter.  Gilbert and Boutin [34] presented some evidence that snowshoe hares tend to avoid open areas during bright phases of the moon and during bright periods of a single night.  Snowshoe hare activity usually shifts from coniferous understories in winter to hardwood understories in summer [56]. Home Range:  Vegetative structure plays an important role in the size of snowshoe hare home ranges.  Snowshoe hares wander up to 5 miles (8 km) when food is scarce [3].  In Montana home ranges are smaller in brushy woods than in open woods [1].  In Colorado and Utah the average home range of both sexes was 20 acres (8.1 ha) [25].  On Montreal Island of Quebec, the average daily range for both sexes was 4 acres (1.6 ha) in old-field mixed woods [8].  In Montana the home range averaged 25 acres (10 ha) for males and 19 acres (7.6 ha) for females [1].  In Oregon the average snowshoe hare home range was 14.6 acres (5.9 ha) [58]. COVER REQUIREMENTS : Snowshoe hares require dense, brushy, usually coniferous cover; thermal and escape cover are especially important for young snowshoe hares [20,35].  Low brush provides hiding, escape, and thermal cover.  Heavy cover 10 feet (3 m) above ground provides protection from avian predators, and heavy cover 3.3 feet (1 m) tall provides cover from terrestrial predators [16].  Overwinter survival of snowshoe hares increases with increased cover [51].  A wide variety of habitat types are used if cover is available.  Base visibility in good snowshoe hare habitat ranges from 2 percent at 16.5 feet (5 m) distance to 0 percent at 66 feet (20 m).  Travel cover is slightly more open, ranging from 14.7 percent visibility at 16.5 feet (5 m) to 2.6 percent at 66 feet (20 m) [16].  Wolfe and others [81] reported that areas with horizontal vegetation density of 40 to 100 percent at 50 feet (15 m) are adequate snowshoe hare habitat in Utah [80]. FOOD HABITS : Snowshoe hares eat a variety of plant materials.  Forage type varies with season.  Succulent green vegetation is consumed when available from spring to fall; after the first frost buds, twigs, evergreen needles, and bark form the bulk of snowshoe hare diets until spring greenup [9,53]. Winter Foods:  Snowshoe hares prefer branches, twigs, and small stems up to 0.25 inch (6.3 mm) diameter; larger stems are sometimes used in winter [35].  In Yukon Territory snowshoe hares normally eat fast-growing birches and willows and avoid spruce.  At high snowshoe hare densities, however, the apical shoots of small spruce are eaten [68].  The snowshoe hare winter diet is dominated by bog birch (Betula glandulosa) which is preferred but not always available.  Greyleaf willow (Salix glauca) is eaten most often when bog birch is not available.  Buffaloberry (Shepherdia canadensis) is the fourth most common diet item.  White spruce (Picea glauca) is eaten but not preferred.  In Alaska spruce, willows, and alders comprise 75 percent of snowshoe hare diets; spruce needles make up nearly 40 percent of the diet [79].  In northwestern Oregon winter foods include needles and tender bark of Sitka spruce, Douglas-fir, and western hemlock (Tsuga heterophylla); leaves and green twigs of salal; buds, twigs, and bark of willows; and green herbs [53].  In north-central Washington willows and birches are not plentiful; snowshoe hares browse the tips of lodgepole pine seedlings [47].  In Utah winter foods include Douglas-fir, willows, snowberry (Symphoricarpos spp.), maples, and serviceberry (Amelanchier spp.).  In Minnesota aspens, willows, hazelnut (Corylus spp.), ferns (Pteridophyta spp.), birches, alders, sumacs (Rhus spp.), and strawberries (Fragaria spp.) are winter foods.  In New York winter foods include eastern white pine, red pine (Pinus resinosa), white spruce, paper birch, and aspens [52].  In Ontario sugar maple (Acer saccharum), striped maple (A. pensylvanicum), red maple, other deciduous species, northern white-cedar (T.  occidentalis), balsam fir, beaked hazelnut (C. cornuta), and buffaloberry were heavily barked [22].  In New Brunswick snowshoe hares consumed northern white-cedar, spruces, American beech (Fagus grandifolia), balsam fir, mountain maple (A.  spicatum), and many other species of browse [74].  In Newfoundland paper birch is preferred [24].  Further details on regional food preferences are summarized in Bittner and Rongstad [9]. Spring, Summer, and Fall Foods:  In Alaska snowshoe hares consume new leaves of blueberries (Vaccinium spp.), new shoots of field horsetails (Equisetum arvense), and fireweed (Epilobium angustifolium) in spring. Grasses are not a major item due to low availability associated with sites that have adequate cover.  In summer leaves of willows, black spruce, birches, and bog Labrador tea (Ledum groenlandicum) are also consumed.  Black spruce is the most heavily used and the most common species in the area.  Pen trials suggest that black spruce is not actually preferred.  Roses (Rosa spp.) were preferred but a minor dietary item as they were not common in the study area [79].  In northwest Oregon summer foods include grasses, clovers (Trifolium spp.), other forbs, and some woody plants including Sitka spruce, Douglas-fir, and young leaves and twigs of salal [53].  In Minnesota aspens, willows, grasses, birches, alders, sumacs, and strawberries are consumed when green [52].  In Ontario summer diets consist of clovers, grasses, and forbs [22]. PREDATORS : The snowshoe hare is a major prey item for a number of predators.  Major predators include lynx (Lynx lynx), bobcats (L. rufus), fishers (Martes pennanti), American martens (M. americana), long-tailed weasels (Mustela frenata), minks (M. vison), foxes (Vulpes and Urocyon spp.), coyote (Canis latrans), domestic dogs (C. familiaris), mountain lions (Felis concolor), domestic cats (F. catus), great horned owls (Bubo virginianus), barred owls (Strix varia), spotted owls (S. occidentalis), other owls, red-tailed hawks (Buteo jamaicensis), northern goshawks (Accipiter gentilis), other hawks (Buteonidae), golden eagles (Aquila chryseatos), and crows and ravens (Corvidae) [9,16,35,53,59,75].  Other predators include northern short-tailed shrews (Blarina brevicaula) and black bears (Ursus americanus) [9,75]. In Glacier National Park snowshoe hares are a prey item of Rocky Mountain wolves (Canis lupus irremotus) [40]. MANAGEMENT CONSIDERATIONS : The snowshoe hare is an economically important species; its economic impact varies with season, region, and population cycle [9].  It is important prey for many furbearers (coyote, foxes, fishers, etc.), but does not itself produce economically important fur.  Its importance as prey creates secondary effects during population lows; predators seeking other food sources often increase predation rates on preferred game species such as ruffed grouse (Bonasa umbellus) [42].  The snowshoe hare is a small game animal and is important as human food in some remote areas [3].  It is a pest in tree plantations [53] and causes damage to both managed and unmanaged conifer stands in the Pacific Northwest [35]. Importance as Prey:  Management of furbearers and sensitive predator species is often dependent on snowshoe hare management as they are a major prey item for many carnivores.  Lynx, considered a sensitive species in Washington, can be maintained only with management for their main prey, the snowshoe hare.  In north-central Washington a patchwork of early successional stands favored by snowshoe hares and old-growth forest needed by lynx for denning is recommended [83].  Logging and thinning units of less than 40 acres (16 ha) encourage natural forest regeneration; it is recommended that management units be greater than 20 to 25 acres (8-10 ha) (i.e., larger than the average snowshoe hare home range) to encourage snowshoe hare use and thus benefit lynx [47].  In Alberta winter coyote density is directly related to snowshoe hare abundance.  Coyotes switch to alternate prey species only when snowshoe hares become relatively scarce [76]. Black and others [10] surveyed animal damage to conifer plantations in Oregon and Washington based on data obtained from 1963 to 1975. Snowshoe hare damage was substantial to Douglas-fir plantations; in many cases tree damage was second only to that caused by mule deer (Odocoileus hemionus).  It must be noted that snowshoe hare populations peaked in 1971 and 1972.  During population lows most damage to conifer plantations consists of clipping of small-diameter stems, twigs, and branches.  Barking becomes serious at high snowshoe hare densities [35]. Snowshoe hare damage birch seedlings by clipping twigs, terminal shoots, and stems, or by gnawing bark and partially or completely girdling trees [41]. Control:  All direct control methods are effective only in the short term.  Lethal control methods are subject to state and local regulations.  Shooting snowshoe hares is costly of time and personnel, and is not always effective.  Trapping is costly.  Toxic baits are not always legal.  Nonlethal methods include repellents, which can be effective but costly, and exclusion fencing, which is also costly [27,35]. Indirect control of snowshoe hares consists of habitat management to reduce cover.  Silvicultural practices can be modified to reduce snowshoe hare use of an area; brushy areas attract snowshoe hares. Second-growth stands with dense brushy understories and high sapling densities are optimum snowshoe hare habitat.  Thinning often creates good snowshoe hare habitat when it encourages denser growth of shrubs [35].  Snowshoe hares also favor clearcut blocks adjacent to pole-size timber; edges are the areas of greatest snowshoe hare activity [35]. In British Columbia population density and recruitment of snowshoe hares increased significantly in thinned stands of lodgepole pine during the first winter but declined thereafter.  Thinning overstocked lodgepole pine had little or no effect on reproduction or survival of snowshoe hares but reduced average body weights [72].  In aspen-birch stands reduction of coniferous cover in cutover areas reduces use by snowshoe hares [41].  Evans [27] suggested that snowshoe hare damage is probably reduced where slash and brush are disposed of by burning.  In quaking aspen (Populus tremuloides) stands in Alberta, intensive regeneration and periodic removal of competing brush promotes fast early growth and reduces snowshoe hare damage [26].  Other recommendations include timing conifer plantation establishment during the low phase of the snowshoe hare population cycle, using larger planting stock with a reduced fertilizer regime, and selection of tree species based on snowshoe hare preferences [35,71,72]. The possibility of raising Douglas-fir stock that is less palatable to snowshoe hares has been discussed [23]. Parasites and diseases of snowshoe hares have been studied extensively and were summarized by Bittner and Rongstad [9].


WILDLIFE SPECIES: Lepus americanus
DIRECT FIRE EFFECTS ON ANIMALS : Severe fire can kill small mammals but adult snowshoe hares are probably able to escape most fires.  In central Alberta pre- and postfire population estimates indicated that there was little or no direct mortality caused by a severe to moderately severe June 1964 fire.  No snowshoe hare carcasses were found in an immediate postfire sweep of the area even though a few dead voles (Microtus spp.) were found (presence of vole carcasses indicated that showshoe hare carcasses would not have been completely consumed by fire).  Following a severe fire in 1968 two adult snowshoe hares were flushed from blackened and smoldering areas but the snowshoe hares left the burned site shortly afterward [43]. Komarek [48] compiled a table of observations of wildlife response to fire.  He listed snowshoe hares as attracted to fire and smoke, present on black burns (snowshoe hares have been observed consuming ash and char), and present on newly greened burns.  In the Northwest Territories snowshoe hares used a burn (severe fire in August 1981) the first winter after fire; black spruce with bark charred by the fire were girdled by snowshoe hares.  Snowshoe hares ate charred black spruce bark on burned plots but did not consume bark on unburned plots.  Small black spruce were preferred over large-stemmed trees.  Use of the burned areas was higher than use of adjacent unburned areas.  (A laboratory test of heated black spruce bark indicated that it is lower in resins and waxes (unpalatable substances) than unheated controls.)  By 1982 and 1983 there was little new growth and much exposed mineral soil [70]. Snowshoe hares often abandon fresh burns if cover is sparse and nutritious browse is available elsewhere.  In Alberta quaking aspen stands with a history of recurrent fire supported a moderate snowshoe hare population.  A severe fire in May 1968 killed all aboveground vegetation.  Snowshoe hares completely avoided the severely burned area until April 1969 after quaking aspen and balsam poplar had established [43].  Freshly burned clearcuts are poor snowshoe hare habitat; however, older brushy areas are desirable.  In west-central Oregon old-growth stands of Douglas-fir were clearcut and burned.  Snowshoe hares were not present on the burned area the first year after the fire [32]. Burns are increasingly occupied by snowshoe hares as plant succession progresses.  In central Alberta a severe 1968 fire was not appreciably green until summer of 1969.  Snowshoe hare population density on the moderately burned and unburned areas increased after the fire, largely due to an influx of the snowshoe hares from the severely burned sites. By late summer of 1969 snowshoe hare runways were common and well used in the severely burned areas [43].  In the September following a July 1971 wildfire (Alaska), snowshoe hares consumed nearly all the postfire willow sprouts.  During the winter of 1971-1972 (a snowshoe hare population high in Alaska) snowshoe hares consumed large quantities of charred bark (spruce, aspens, and birches).  The second winter after the fire snowshoe hares consumed all of the aspen sucker regrowth in several stands.  During the 2 years following the fire 100 percent of available hardwood browse was consumed in the unburned control.  The snowshoe hare population declined from 1972 to 1974 in both the burned and unburned plots.  Snowshoe hares were not observed on the burned plots from 1974 to 1976, the last year reported [77]. HABITAT RELATED FIRE EFFECTS : Nearly every plant that is important to snowshoe hares is favored by fire:  jack pine, lodgepole pine, black spruce, quaking aspen, birches, blueberries, fireweed, eastern white pine, white spruce, northern white-cedar, tamarack, and eastern hemlock are all fire followers to some extent and are used by snowshoe hares for food and/or cover [36]. Fire, even at moderatly long intervals, maintains a mosaic of successional stages which provide good snowshoe hare habitat [65].  In summer forbs and the leaves of shrubs are abundant and nutritious on recently burned areas [45].  Snowshoe hares depend on small, new stems which are available in large amounts on recently burned areas [36].  In Alaska small fires or large fires with unburned areas of black spruce or other heavy cover provide good to optimal habitat for snowshoe hares [45].  In Alaska a 3-year-old burn provided willow browse for snowshoe hares [78].  In north-central Washington fire suppression has limited the amount of early-successional forest.  The prevalence of older, suboptimal habitats does not provide enough browse for snowshoe hare populations to sharply increase and therefore snowshoe hare populations in the area are low but stable [46]. Periodic fire that results in an increase in dense, brushy cover is beneficial to snowshoe hares.  In Minnesota a large prescribed fire set in 1925 escaped and burned a few thousand acres.  The area was seeded in by jack pine which, after eleven growing seasons, supported a large snowshoe hare population [36].  Snowshoe hares populations have increased after fire in Acadia National Park, Maine [60]. Areas that are burned frequently enough to reduce the height and density of brushy cover would not be used much by snowshoe hares.  In northwestern Minnesota mature quaking aspen stands were converted to open brushlands with repeated prescribed fires over a 17-year period. Study plots were burned in spring 1968, 1971, 1973, and 1975.  The number of snowshoe hare pellets counted fluctuated with burning; snowshoe hare pellets decreased immediately following fire and gradually increased until the next fire.  After the fourth fire snowshoe hare numbers and rate of increase were both very low [4].  Mean frequency of snowshoe hare observations was higher on control areas (48%) than on burned areas (33%).  After 1973 ground cover was sparse on burned areas [5]. FIRE USE : Prescribed fire could be used to improve snowshoe hare habitat by creating openings and early successional habitat.  Fire at less than 5- to 10-year intervals may result in repeated increases and decreases in snowshoe hare populations [36].

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