FIRE EFFECTS AND USE
WILDLIFE SPECIES: Rangifer tarandus | Caribou 



DIRECT FIRE EFFECTS ON ANIMALS : 
Davis and Franzmann [9] stated that barren-ground caribou are usually in
tundra habitat during the taiga fire season, so therefore could easily
avoid fire.  No reports are given for direct fire effects on woodland
caribou.


HABITAT RELATED FIRE EFFECTS : 
Fire was once thought to be detrimental to caribou because it destroys
the slow-growing lichens formerly considered primary caribou food.  As a
result much of the literature on fire and caribou describes its effects
on lichen communities.  Several authors have reviewed literature which
presents conflicting opinions about fire's role in caribou habitat
maintenance.  These authors now believe that fire is beneficial to
caribou in the long-term [9,15,17,18,19,25].  There is no dispute that
fires can kill important lichen species and that these lichens can take
a minimum of 30 years to recover [25,30,34].  However, there is dispute
over what constitutes recovery, and lichen reestablishment does not
always lead to caribou recovery [21].  Scotter [30] listed growth rates
for various lichen species.  The establishment of a lichen crop after
fire may be more related to grazing pressure by caribou and fire
severity than to the number of years since a previous burn [23].
Edwards [10] blamed extensive, lichen-destroying fires in 1926 in Wells
Grey Park, British Columbia, for the decline of caribou.  Later others
surmised that increased predator success due to cover removal was
responsible [9].  Similarly caribou on the Kenai Peninsula, Alaska, may
have declined following fire more in response to increased predation
than to reduction of forage [9].

Bergerud [3] stated that fires would be beneficial to lichen if
closed-canopy forests converted to lichen woodland or shrub barrens.
But if lichen woodlands became permanent shrub barrens, fire would
reduce forage.  Klein [18,19] listed short-term and long-term effects of
fire on caribou populations.  Some positive effects of fire include
maintenance of plant diversity, rejuvenation of old-growth forests with
declining lichen populations, and removal of bryophytes which would
stimulate lichen growth [3,18,19,25].

Schaefer and Pruitt [36] conducted a study to determine the short and
long-term effects of fire on the Aikens caribou herd in Manitoba,
concluding that the short-term effects on forage quality are severe.  The
effects of fire are largely based on the importance of winter and summer
ranges to caribou populations.  Loss of winter range lichens that
constitute population determining energy requirements will put pressure
on summer ranges to provide the lost energy.  Therefore, access to other
lichen-rich stands must be available.  Fire can also increase downfall
timber, limiting access to foraging areas.  Downed timber 1.5 to 3 feet
(0.5-1 m) deep can inhibit accessibility or caused caribou to expend 
great amounts of energy to obtain forage [36].  Increased snowfall in
burned areas also reduces accessibility.


FIRE USE : 
Fire can be used to create a diversity of forage species and enhance
lichen growth in the long-term.  Fire also returns nutrients to the soil
and reduces certain plant species that compete with preferred forage.
Many authors have recommended burning bryophyte communities to stimulate
lichen growth [9,18,19,23,25,27,31].  Fire may actually be required to
maintain healthy lichen communities over a long period of time [25].
However, frequent fires will prevent the establishment of old-growth
forests that harbor important forage lichens and cover.  Fires might
also replace treeline forests with less favorable, drier habitat
[15,18,19].  Russell [28] recommended against burning permafrost
communities because fire effects on these communities are not yet known.
He also recommended against suppression of wildfires solely to protect
caribou habitat.  When burning, it is important to maintain a
heterogeneity of cover in wintering areas [23].  Ahti and Hepburn [2]
suggested burning Sphagnum fuscum peatlands after 40 to 50 years to
increase lichens.  They concluded that burning spruce muskegs produces
"considerable" lichen, as does ground fire in old-growth jack pine
(Pinus banksiana) stands and fire on mossy rock outcrops.  Because
lichens need a layer of loose soil to establish, it is better to burn
patches of moss than to strip rocks bare of vegetation.  For tundra
heaths, Ahti and Hepburn [2] recommended burning only one-third of a
stand in need of improvement at a time.  Another third should be burned
after the first has recovered.  The key to fire maintenance of caribou
habitat is to provide alternative, accessible, energy-rich summer and
winter habitats within a herd's range [36].


REFERENCES : 
NO-ENTRY

Related categories for Wildlife Species: Rangifer tarandus | Caribou