Survival and abundance of three species of mice in relation to density of shrubs and prescribed fire in understory of an oak woodland in California

We investigated effects of prescribed understory fire and shrub density on the pinyon deermouse (Peromyscus truei), brush deermouse (P. boylii), and California pocket mouse (Chaetodipus californicus) in a mixed blue oak-coast live oak (Quercus douglasii-Q. agrifolia) woodland of coastal-central California. We simultaneously estimated survival and abundance of all species during pre-burn and post-burn. Abundance of pinyon deermice and California pocket mice was significantly higher in plots with high (>25%) shrub cover compared to plots with low (<10%) shrub cover. A light-to-moderate intensity, prescribed, understory fire had no significant effect on survival for any of the three species we investigated. The fire significantly reduced abundance of pinyon deermice in the trapping session immediately after the fire, but abundance increased in subsequent trapping sessions relative to controls. Low intensity, prescribed, understory fire in oak woodland is unlikely to significantly alter populations of rodents if patches of well-structured habitat are maintained. Benefits of prescribed fire for oak woodlands in reduction of the risk of wildfire and rejuvenation of vegetation likely outweigh any short-term negative effects on populations of mice.