Small Mammals in Farmstead Shelterbelts: Habitat Correlates of Seasonal Abundance and Community Structure

Abstract

Small mammals were studied from Sept. 1978 to Nov. 1980 in 5 Minnesota [USA] farmstead shelterbelts. Based on correlations between habitat variables characterizing vegetative features of shelterbelts and numbers of individuals captured in each season, Peromyscus leucopus and Clethrionomys gapperi were considered woodland species, Microtus pennsylvanicus as a grassland species, and Sorex cinereus and Blarina brevicauda is intermediate in terms of their dependency on shelterbelts. Area and perimeter of shelterbelts were associated with numbers of all species except C. gapperi. Numbers of P. leucopus and C. gapperi tended to be higher in shelterbelts that were isolated from other wooded habitat; numbers of S. cinereus were lower in isolated shelterbelts. Species richness was greater in larger shelterbelts with complex vegetative structure. Species of small mammals residing in shelterbelts were those that typically are not considered as agricultural pests. Management recommendations include maintenance practices that do not reduce stratification of vegetation, leaving woody and man-made debris within shelterbelts, and establishing shelterbelts that are as large as possible within the economic constraints of farming. These recommendations simultaneously would benefit other species of mammals and birds in the intensively farmed regions of the Midwest.