FIRE EFFECTS AND USE
WILDLIFE SPECIES: Lepus americanus | Snowshoe Hare 



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].


REFERENCES : 
NO-ENTRY

Related categories for Wildlife Species: Lepus americanus | Snowshoe Hare