FIRE EFFECTS AND USE
WILDLIFE SPECIES: Sialia mexicana | Western Bluebird 



DIRECT FIRE EFFECTS ON ANIMALS : 
There are no reports of direct western bluebird mortality due to fire;
nestlings and nests are probably vulnerable, however.  Fast-moving,
intense chaparral fires have the potential to kill birds and/or create
extreme stresses (panic, dehydration) [41].


HABITAT RELATED FIRE EFFECTS : 
Postfire successional communities are usually attractive to western
bluebirds, especially in the first few years following the fire [48].
In Kern County, California, western bluebirds were recorded prior to a
July 1954 prescribed fire in scrub woodlands dominated by blue oak
(Quercus douglasii), gray pine (Pinus sabiniana), interior live oak (Q.
wislizenii), and wedgeleaf ceanothus (Ceanothus cuneatus).  By 3 years
after the fire, western bluebird densities had nearly doubled [37].  In
southwestern Idaho a ponderosa pine-Douglas-fir forest that burned in
1992 was censused in 1994.  Most of the trees on the plot were dead.
Cavity nesters in the area included western bluebirds (17 nests on
7,813 acres [3,163 ha]) [48].  Based on data from Brawn and Balda [12],
Hejl [30] hypothesized a western bluebird population decrease for
southwestern ponderosa pine forests since fire exclusion has led to
increased amounts of closed forest.  

Snag availability in postfire communities is a substantial positive
influence on western bluebird activity [49].  On the Olympic Peninsula
western bluebirds were detected on 30- to 50-year-old Douglas-fir
plantations in dense patches of fire-killed snags; they were not
detected on plots without snags nor in younger and older plots with
snags [59].  Hutto [34] emphasizes the importance of snags and strongly
recommends against salvage cutting of burned forests; the abundance of
newly killed trees and concomitant woodpecker activity is particularly
valuable to western bluebirds for nest cavities.  If salvage logging is
unavoidable (for sanitary or firebreak reasons) then some areas should
be left untouched rather than thinning the entire unit [34].

Loss of vegetative cover due to fire is detrimental to most small birds,
leaving them vulnerable to raptors, especially in large, severe fires
which leave few unburned refuges.  In San Dimas, California, western
bluebirds initially declined in immediate postfire chaparral
communities, probably due to lack of fruit [58].


FIRE USE : 
Savannas and open stands of mature pine are natural western bluebird
habitat that require recurrent fire for maintenance.  Prescribed fire is
usually beneficial to western bluebird especially if it reduces shrubs
and understory trees [43].


REFERENCES : 
NO-ENTRY

Related categories for Wildlife Species: Sialia mexicana | Western Bluebird