FIRE EFFECTS AND USE
WILDLIFE SPECIES: Ursus arctos | Grizzly Bear 



DIRECT FIRE EFFECTS ON ANIMALS : 
Direct fire-related mortality probably occurs but may not have a
significant impact on the grizzly bear population as a whole [44].


HABITAT RELATED FIRE EFFECTS : 
Many authors have blamed fire suppression in some areas for the decline
of grizzly bear [7,25,35,36].  Fires can promote and maintain many
important berry-producing shrubs and forbs, as well as provide a medium
for insects and in some cases carrion.  Referring to the Yellowstone
National Park fires of 1988, Blanchard and Knight [44] stated: "The most
important apparent immediate effect of fires on grizzly bears was the
increased availability of some food items, especially carcasses of elk."
Studies in western Montana showed that spring burning in
Douglas-fir-ponderosa pine (Pinus ponderosa) types promoted huckleberry
sprouting [24].  The number of stems present after burning were closely
related to the number present before burning.  Grouse whortleberry
(Vaccinium scoparium) declined following fire in western Montana because
its shallow rhizomes were killed by the heat [37,38].  In the same study
most shrubs occurred on sites burned 35 to 70 years previously.  Martin
[21] found that huckleberry was most productive on sites burned between
25 to 60 years previously or on sites clearcut and burned 8 to 15 years
previously.  Huckleberry on sites left untreated for more than 60 years
was least productive.  Other shrubs that respond well to overstory
removal and broadcast burning are elderberry (Sambucus spp.), Sitka
mountain ash, serviceberry, and buffaloberry [15].  


FIRE USE : 
Fire can be used to create and maintain seral shrub communities for
grizzly bear by rejuvenating shrubs, releasing nutrients, and
discouraging conifer dominance [25,37].  In the case of postharvest
treatment, many authors recommend broadcast burning and discourag dozer
pile burning.  The latter method can damage rhizomes, root crowns, and
the soil [4,16,29,37,39].  Natural fire programs as well as prescribed
burning for improved grizzly habitat are encouraged and practiced by
some National Forests [7,11,16,25,35].  Garcia [11] and Holland [16]
discuss burning practices on the Kootenai and Flathead National Forests.
A fire-induced increase of berry-producing shrubs may only be beneficial
if spread over large areas that encompass home ranges of several bears
[33].  However, prefire plant composition may dictate postfire
composition [24].  Berry-producing shrubs must be provided continually
over time to be beneficial [15].  Miller [24] recommends burning
huckleberry during spring in Montana Douglas-fir-western larch (Larix
occidentalis) communities.  Also, burning should be conducted when duff
is damp; fires that remove most of the duff often reduce huckleberry
density.


REFERENCES : 
NO-ENTRY

Related categories for Wildlife Species: Ursus arctos | Grizzly Bear