Interactions in Microhabitat Use between Dipodomys Ordii and Onychomys Leucogaster

Hypothesis attempting to explain structure in desert rodent assemblies have emerged primarily from studies dealing with heteromyid interactions. Little attention has been given to the cricetid elements in the community, despite their often high densities and year—round activity in close association with heteromyid species. This study extends the understanding of desert rodent assembly dynamics by examining interactions in microhabitat use between Dipodomys ordii (Heteromyidae) and Onychomys leucogaster (Cricetidae). Research was designed to test the hypothesis: in a two species (experimental) enclosure, microhabitat use by each species will not differ from that in one species (control) enclosures. Results indicate that D. ordii shifts microhabitat use when co—occurring with O. leucogaster, while the reverse does not occur. This outcome shows that interactions are operating between these two species. Further, studies and aimed at determining presumed structure among desert rodent species may be lacking information on significant nonheteromyid elements of the community.