Habitat Utilization, Competitive Interactions, and Coexistence of three Species of Cricetine Rodents in East‐Central Arizona

The ecological relationships of three cricetine species–Peromyscus maniculatus, Peromyscus boylii, and Neotoma stephensi–and their utilization of habitat were revealed by species removals from unfenced plots and vegetation tailoring experiments. When N. stephensi, a woodland and shrubland species of woodrat, was removed from a manzanita—oak shrubland and pinyon—juniper woodland, P. boylii showed few significant changes in its use of the vegetational microhabitats on the grid or in the nature of its arboreal activity. However, when P. boylii, a woodland and shrubland mouse, was removed from a grid in juniper—oak shrubland and juniper grassland, both P. maniculatus, an inhabitant of open habitats such as grassland, and N. stephensi expanded their microhabitat utilization and changed their patterns of aboveground activity. Subsequent removal of both N. stephensi and P. boylii from this plot resulted in further expansion of arboreal activity by P. maniculatus. After crown removal of 0.75 ha of manzanita—oak shrubland, P. boylii, but not N. stephensi, avoided the newly opened area. Habitat selection, differential resource utilization, and interspecific competition all contribute to the coexistence of these three species in patchy habitats.