Communities of Small Mammals in Six Grass-dominated Habitats of Southeastern Oklahoma

During autumn 1991, we sampled small mammals in six grass-dominated habitats including upland ungrazed native prairie, upland improved pastures, upland mowed native prairie, upland roadside fencerows, lowland ungrazed native prairie and lowland ungrazed native prairie with forbs and shrubs in southeastern Oklahoma. Eleven species of small mammals were represented in 405 captures. Species diversity (H′) was high in upland (1.57) and lowland (1.47) ungrazed prairie and least for upland fencerows (0.86). Evenness (J′) exhibited a similar pattern and was high in upland (0.88) and lowland (0.82) ungrazed prairie and least for lowland ungrazed prairie with forbs and shrubs (0.53). Community overlap (Ro) varied from 1.00 (upland improved pastures and upland roadside fencerows) to 0.57 (upland improved pastures and upland ungrazed prairie). Abundance of small mammals was greatest in fencerows, largely due to the prevalence of hispid cotton rats (Sigmodon hispidus). Different land-use practices elicited both positive and negative species-specific responses. Current human activity in some locations may produce habitat mosaics that result in an overall greater abundance and diversity of small mammals.