Populations of many small mammals in the western United States have declined as a consequence of changes in land-use patterns over the past century. In California's Central Valley these changes have resulted in replacement of native grassland vegetation by non-native annual grasses. Jepson Prairie is a natural reserve that has been set aside to preserve native vernal pool and bunchgrass habitats. Jepson Prairie also provides habitat for several state and federally listed threatened or endangered species, including plants insects, and vertebrates. Current management of the reserve includes prescribed burning and grazing by domestic sheep to foster restoration of native grasses. We examined the effects of prescribed burning on small mammals by censusing small mammal communities inhabiting burned and unburned habitats over a one-year period. Nine censuses (6720 trap-nights) resulted in a total of 215 captures of five species. Three of these species (deer mouse, Peromyscus maniculatus, California vole, Microtus californicus, and Botta's gopher, Thomomys bottae) are common in many parts of California. The remaining two are either reduced in numbers (California kangaroo rat, Dipodomys californicus) or listed as Federal Special Concern (FSC) species by the state of California (San Joaquin pocket mouse, Perognathus inornatus inornatus); it is worth noting that only one capture was made of the latter species. In general, extremely low and varying capture rates suggest that Jepson Prairie may be poorly suited to supporting populations of small mammals, although habitat management could substantially improve conditions for these species. For sites such as Jepson Prairie to be managed to maintain small mammal populations, we recommend 1) acquisition of upland habitat to provide refuge from seasonal flooding; 2) control of domestic and feral cats; and 3) a comprehensive prescribed burning program to restore native plant species, reducing the need for grazing.
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