Preliminary mammal survey of Fossil Butte National Monument, Wyoming

The mammalian community of Fossil Butte National Monument, Wyoming, consisted of at least 45 species. Snap trap sampling of the smaller species combined with sight and sign observations of the larger species formed the basis of this preliminary survey in the summers of 1974 and 1975. Snap - trapping samples (2880 trap days) yielded 44 least chipmunks and 89 deer mice. The distribution of all species was characterized by plant community occupancy. Heavy domestic livestock use of the communities nearest water has resulted in severe alteration in community structure; this has probably affected the distribution and abundance of at least some of the smaller mammals.