Brush Mouse - Cover Requirements

Cover Requirements

No significant differences in habitat use between genders were observed in Arizona. Typical brush mouse habitat in southern Arizona was characterized by 74% tree cover, 60% leaf cover, 21% shrub cover, and 16% rock cover. Additionally, 67% of all brush mice relocated by radiotelemetry in the study were located in a riparian zone with the other observations occurring in uplands and an intermittent stream channel. Brush mice used sites with significantly (P<0.05) more rock cover (19% to 22%) during winter and spring than at other times of the year. Also in spring, plots with the most brush mice also had significantly (P<0.05) more shrub cover (21% vs.14%) and succulents (9% vs. 2%) than random plots.

In a New Mexico study, 27% of brush mice captured were taken around rocky areas, 10% under Gambel oak (Q. gambelii), 9% under juniper, and 7% each around woodpiles and sacahuista. Less frequently, brush mice were taken under or around pinyon pine, gray oak (Q. grisea), Apache plume, rabbitbrush, mountain-mahogany, white fir (Abies concolor), Douglas-fir (Pseudotsuga menziesii), locust (Robinia spp.), prickly-pear, cholla (Opuntia spp.), chokecherry (Prunus spp.), bricklebush (Brickellia spp.), and grape (Vitis spp.).

In southern California, brush mice were captured on leaf mold in an oak hardwood association of coast live oak, white alder (Alnus rhombifolia), whiteflower currant, and sumac (Rhus spp.). They were also trapped under logs and dense vegetation and on wet seepage slopes next to a creek. In coastal California, brush mice were captured primarily under coast live oak, false-willow (Baccharis douglasii), California buckeye, and California bay.

Fallen logs and rock outcrops provide nest sites for the brush mouse. They may also construct nests in tree hollows and underground burrows. Brush mice living in mine shafts or caves build nests similar to those of goldfinches. Davis noted that the brush mouse nest is a "globular structure" and is constructed primarily of dried grasses within natural cavities. Brush mouse nest sites in California were found on sites with a high density coast live oak (Q. agrifolia) overstory and an open understory with low vegetation and ground cover.