This study was conducted on the Badger Mountain grazing allotment of the Sheldon National Wildlife Refuge (NWR), Nevada where a 925-acre (375 ha) cattle exclosure was built to evaluate grazing impacts. The study objectives were to measure the effects of grazing on: 1) small mammal numbers and reproduction, 2) passerine bird numbers and habitat use, and 3) mule deer (Odocoileus hemionus) food habits and dietary quality. Deer mice (Peromyscus maniculatus), least chipmunks (Tamias minimus), and Great Basin pocket mice (Perognathus parvus) comprised over 90% of 601 small mammals caught in snap traps. Sagebrush voles Lagurus curtatus) occurred in small numbers, primarily within the cattle exclosure. Numbers of other small mammal species were comparable inside and outside the exclosure. Passerine bird numbers were similar between the exclosure and grazed site, with Brewer's sparrows (Spizella breweri) and green-tailed towhees (Pipilo chlorurus) the most numerous species (24% and 14%, respectively. of 425 individuals counted). Diversity of birds was lowest in the shrubby rolling hills and mahogany rocklands ecosites and greatest in the edge between the two. Food habits of two tame mule deer were observed in six feeding pens. Deer ate similar foods during the pre-cattle grazing trial, but they selected a greater percentage of forbs and grasses inside the exclosure during the post-cattle grazing trial. A multiresource approach to studying the effects of grazing on wildlife and their habitats provides the manager more options when managing the grazing system.
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