Small Mammal Movements In Previously Burned Habitats

Fires have the ability to reshape entire landscapes, changing the composition of plants species as well as the structure of the terrain. Forest fires also leave behind a large amount of coarse woody debris, i.e., downed logs, which can provide small mammals with habitat, cover from predators, and have the potential to alter movement patterns. Movement patterns are also influenced by other habitat features, such as the separation of habitat by a road. For this study I utilized capture-recapture data from burned and unburned study sites in the Yellowstone National Forest as well as genetic analyses to determine both short and long-term movement patterns relative to species, habitat (burned or unburned), and the presence/absence of a road. I focused specifically on the two most abundant species in the intermountain west: red-backed voles (Myodes gapperi) and deer mice (Peromyscus maniculatus). Capture data indicated that on average deer mice travel greater distances, and both species have greater average movements in burned areas compared to unburned areas. These results are an important complement to the results from genetic analyses, which suggest a decrease in gene flow across the road. Further analysis is needed to determine the causes of the differences between burned and unburned areas, such as diet requirements and vegetative layout. Understanding the impact fires and roadways have on small mammals will not only expand our knowledge on their ecological role but may also implicate the use of controlled burns as tools for population management.