Some Ecological Studies on the Effects of Chaparral Fire on Small Rodent Populations in Southern California
ecology, chaparral fires, California, rodent population, biology
Animal Sciences | Biology | Ecology and Evolutionary Biology | Population Biology
A series of chaparral fires was the impetus for this study of the effects of chaparral fire on populations of small mammals residing there. Mark and recapture live-trappings was utilized in two burned areas and two controls. Peromyscus maniculatus (long-tailed deermouse) and Dipodomys merriami (Merriam's kangaroo rat), along with fewer Neotoma fuscipes (dusky-footed woodrat), were mammals captured in this study, although only the first two were captured in sufficient numbers for comparisons. Population estimates by the Schnabel method, Lincoln Index, and frequency of Capture method suggested lower populations in burned areas for both species, but large standard errors of these population estimates made this trend statistically insignificant. Normal population fluctuations with breeding season occurred in all areas, although at one burn dramatic population bursts correlated with floral regeneration also. Home ranges of both P. maniculatus and D. merriami by the mean distance between recapture method and inclusive boundary strip method tended to be larger in the burned chaparral, according to the recapture data of this study. Body weights, body lengths, and tail lengths of both species tended to be smaller in the burned chaparral, though the differences were not statistically significant. The "fatness ratio" (body length in cm over body weight in gms) suggested, though again not at a statistically significant level, that these animals in the burned chaparral areas are smaller due to relative starvation not a greater preponderance of younger animals.
Perhaps the use of more traps and subsequent capture of more animals would have given statistical significance to these differences between burned and unburned areas, but due to the adaptations these animals have made to the commonly occurring chaparral fires, more trapping might have shown no difference.
Department 1 Awarding Honors Status
Parratt, L. S. (1972). Some Ecological Studies on the Effects of Chaparral Fire on Small Rodent Populations in Southern California (Undergraduate honors thesis, University of Redlands). Retrieved from https://inspire.redlands.edu/cas_honors/435