PARENT SESSION
Symposium #12: Natural Recovery and Restoration of Disturbed Desert Environments in the Mojave Desert .
Organized by: RH Webb and KH Berry
Tuesday, August 6. 8:00 AM to 11:30 AM. Maricopa Meeting Room, TCC.
Long-term response of nocturnal rodents to wildfire in the Mojave and Great Basin Desert ecotone.
Medica, Philip*,1, Esque, Todd2, Haines, Dustin2, DeFalco, Lesley2, Webb, Robert3, 1 USFWS, Las Vegas, NV2 USGS, Las Vegas, NV3 USGS, Tucson, AZ
ABSTRACT- The responses of rodent populations to wildfire in forest and grassland ecosystems are highly variable, but generally rodents in intact ecosystems, adapted to fire, can withstand normal fire intensities and frequencies. In contrast, some desert ecosystems are not thought to be adapted to fire, and the responses of rodent populations to wildfire are unknown. We tested our hypotheses at the Beatley permanent study plots at the Nevada Test Site in southern Nevada. We compared rodent populations in Yucca brevifolia- Coleogyne ramosissima associations that were burned at least 40 years ago. We conducted a post hoc analysis of the rodent populations on 12 plots in a random complete block design using 2400 trap nights. Perennial plant density was not significantly different between burned and unburned plots (p>0.05), but cover was (P=0.003). Ten species of rodents were captured on the plots. Nocturnal rodent species richness was not significantly different between burned and unburned plots (p>0.05). Rodent density averaged across species was not significantly different between burned and unburned plots (P=0.75) but Dipodomys merriami densities were significantly greater on burned than unburned sites (p<0.05). These results are consistent with the results of a study conducted nearby that compared post-burn rodent populations within the first few years after a fire. It appears that nocturnal desert rodent populations are adaptable to disturbances by wildfire in this plant association under some conditions. Rodent densities may recover relatively quickly following fire, but these animals may be tracking changes in perennial and annual vegetation instead of responding to elapsed time following the disturbance.
KEY WORDS: rodents, wildfire, long-term, Mojave Desert