Habitat use by small mammals across an agriculture ecotone

Includes bibliographical references (pages [94]-101)Responses of small mammals living on or near agricultural land were measured using live and snap trapping from April to November in 1986 and 1987. A total of ten small mammal species was recorded, with two numerically dominant species, each in a separate habitat type; the others were classified as non-residents or transients. The Meadow vole (Microtus pennsylvanicus) was the dominant species in grassland (abandoned pasture), and the Prairie deer mouse (Peromyscus maniculatus bairdii), was dominant in cornfield. Demographic characteristics were not different from "natural" populations of these species. Responses to habitat features, such as percent cover, effective height, and type of vegetation, varied between the two principal species. Microtus specialized on grasses and was positively correlated with grassland plant species. Peromyscus was a habitat generalist and was correlated with all features and plant species. Microtus was apparently excluded from cornfield by a lack of suitable ground cover, while Peromyscus may have been avoiding competition with Microtus and other species in the grassland. Examination of stomach contents from snap trapping in 1986 yielded similar results to live trapping distributions, although all species were captured in cornfield at some time during eight months of the year, and all species were consuming corn. These results suggest that crops may provide substantial resources, in terms of habitat and forage, to species living in or near croplands, and that farming activities may allow some species to co-exist with competitive dominants by creating or maintaining disturbance regimes that shape the diversity of plant or animal species present.M.S. (Master of Science