FIRE EFFECTS AND USE
WILDLIFE SPECIES: Bufo boreas | Western Toad 



DIRECT FIRE EFFECTS ON ANIMALS : 
There is no published information on mortality of western toads from
fire.  The fact that there are no reports of high mortality for any
herpetile species may indicate that amphibians and reptiles are not
highly vulnerable to fire [26].  Kahn [25] reported that western fence
lizards (Sceloporus occidentalis) survived a serious chaparral fire by
remaining in the soil beneath rocks.  Western toads similarly could
survive fire by remaining in the soil beneath rocks, entering animal
burrows, or by escaping to water; survival in retreats under flammable
materials (logs, stumps, and boards) would depend on fire severity and
moisture conditions.  Komarek [27] states that animals appear to respond
to fire with adaptive behaviors which minimize mortality; he reports
that experiments with different types of prescribed fires resulted in no
discernible amphibian mortality.  Frogs escaped a backing fire by
travelling ahead of the fire, then burying themselves under wet leaves
and soil in a small depression [27].


HABITAT RELATED FIRE EFFECTS : 
Western toads occupy diverse habitats, some of which experience fire
relatively frequently (Douglas-fir forests in drier areas [31]), and
some of which rarely experience fire (riparian zones tend to act as fire
breaks but will burn during extended dry conditions [30]).

No specific information describing the response of western toads and
their habitat to fire was available in the literature.  Western toads
are vulnerable to changes in both terrestrial and aquatic habitat.  They
are, however, found in slightly higher abundance in early seres of
Douglas-fir forests [28].  Severe fires that burn surface objects such
as logs and stumps would immediately decrease available hiding cover for
western toads, but postfire sprouting of shrubby species would result in
a longer-term, overall increase in low hiding cover [30].  Most willow
species sprout after topkill by fire [29], so the amount and thickness
of willow clumps increases after fire.  Crown fires would reduce shade
and surface humidity and decrease the amount of daylight time toads
could spend active after a fire.  Fires during early spring could affect
egg masses by reducing shade and increasing water temperatures.  Any
substantial change in runoff rates, erosion, or water tables caused by
fire could degrade breeding sites.

It is likely that there is a change in the relative amounts of different
types of prey organisms in the postfire diet of western toads.
Immediately after fire, many insects are present but those requiring
shade do not adapt well to the more open conditions.  In the longer term
there are differential responses to fire among prey organisms; ant
populations were one-third higher in burned areas than in unburned
areas, but beetles tend to decrease on burned areas [32].


FIRE USE : 
Specific information concerning prescribed fire as it affects western
toads was not available in the literature.  Conservation of surface
objects used for hiding cover is important in any management decision
[10].


REFERENCES : 
NO-ENTRY

Related categories for Wildlife Species: Bufo boreas | Western Toad