SHINNERY OAK-MESQUITE GRASSLANDS OF

There was relatively little overlap in diet among Dipodomys ordii, Onychomys leucogaster, Neotoma micropus, and Spermophilus spilosoma in the shinnery oak-mesquite (Quercus havardii-Prosopis glandulosa) grassland of southeastern New Mexico. D. ordii primarily consumed Triplasis purpurea, P. glandulosa, Euphorbia, and arthropods; 0. leucogaster predominantly consumed arthropods; N. mi- cropus consumed plant fibers, new growth of dicots, Q. havardii, and P. glandulosa; and S. spilosoma primarily consumed arthropods, new growth of dicots, and grasses. Sexual differences in diet were virtually absent for D. ordii and 0. leucogaster, but there was statistically significant variation in diets among seasons, years, and months (P < 0.05). A sample of approximately 60 specimens would be required to obtain a reasonable estimate of the variety of food items consumed by D. ordii and O. leucogaster.