This paper deals with the ecology and distribution of small mammals in the following plant communities of Cedar Valley, Utah: juniper, greasewood, grass-rabbitbrush, and shadscale. Study periods were in August 1950 and 1951, October 1951, and April 1952 with each community studied 1,440 trap-nights. A combination of the Calhoun ''B" and transect method was employed; plant species and densities were taken and soil samples were checked for moisture content, total soluble salts and mechanical analysis. In the communities studied Dipodomys ordii utahensis (Merriam) is found in greatest abundance on sandy soil and Perognathus parvus olivaceus (Merriam) is found in greater numbers on sandy loam or fine gravelly soils. Peromyscus maniculatus sonoriensis (LeConte) and Reithrodontomys megalotis megalotis (Baird) are controlled in their distribution more by plant cover than by soil type. erognathus longimembris gulosus Hall is apparently restricted to sandy loam soil in shadscale communities, but little can be said of the distribution of Onychomys leucogaster utahensis Goldman as only one specimen was taken. In Cedar Valley there appears to be no uniform correlation between the density of plants and the total population of small mammals. Soil moisture and soil salts affect small mammals only by helping to control the plants, which in turn affect the mammals, but the physical factors of the soil affect only burrowing forms directly and burrowing as well as non-burrowing forms indirectly through those factors' affect on the plants. Sudden and heavy precipitation is suggested as the cause of a distinct reduction in population. Of the mammals taken Peromyscus maniculatus was the most variable in distribution.



College and Department

Life Sciences; Plant and Wildlife Sciences



Date Submitted


Document Type





Animal ecology; Mammals, Utah