URBAN HABITAT: A DETERMINANT OF WHITE-FOOTED MOUSE (PEROMYSCUS LEUCOPUS) ABUNDANCE IN SOUTHERN ILLINOIS

The objective of this study was to assess whether differences in abundance of white-footed mice (Peromyscus leucopus) were related to habitat features within and surrounding 60 sampled bottomland forest patches. Habitat features included patch size, patch shape, and landuse within a 300-m buffer surrounding each patch. During 18,000 trap nights, we captured 1,308 white-footed mice within approximately 3,110 ha of bottomland forest. Type of habitat surrounding a patch was a significant determinant of white-footed mouse abundance. Sample sites where less than 10 individuals were captured were surrounded by a large percentage of upland deciduous forest and a low percentage of urban/ other habitats. Sample sites where 30 or more individuals were captured were surrounded by a large percentage of urban/other habitats and a small percentage of upland deciduous forest. Sites where 10-29 individuals were captured were surrounded by intermediate amounts of upland deciduous forest and urban/other habitat. Although deciduous forest is necessary, it may not be the primary determinant of white-footed mouse abundance. Unsuitable habitat may surround and create islands of high density from which successful dispersion is difficult.