Peromyscus maniculatus (deer mouse) andMicrotus pennsylvanicus (meadow vole) are two common small mammals found in the Lakeshore Nature Preserve. P. maniculatus is known to be a vegetative generalist, whereas M. pennsylvanicus is exclusive to grasses and forbs. This study measured relative abundance of both mice species in habitats of varying vegetative ground cover (GC). Live traps were set in four areas; woods (low GC), grass field (high GC), garden (moderate GC) and prairie (high GC). With a total of 57 animals trapped over an eight-day period, M. pennsylvanicus had greater abundance in high GC, whereas P. maniculatus had significantly higher abundance in low to moderate GC. This study lends support for habitat differentiation among M. pennsylvanicus andP. maniculatus based on vegetative cover.