Date of this Version
Pine voles (Microtus pinetorum) have long been recognized as a pest species in fruit orchards of the eastern United States (Hamilton 1935). These semifossorial rodents construct tunnel systems beneath apple trees where they eat entire roots or strip roots of bark and cambium. Hamilton (1938) reported numbers of pine voles within apple orchards as high as 200-300 voles per acre which is in sharp contrast to the relative scarcity of pine voles outside orchard situations (Crain and Packard 1966; Goertz 1971), These findings suggest that orchard habitat provides excellent conditions for pine vole growth and reproduction, although the specific components which are attractive to pine voles and facilitate their proliferation remain poorly understood. Prior studies have suggested that pine vole habitat selection is based on preference for a complex of habitat components including cover density (Benton 1955; Paul 1970; Goertz 1971), food resources (Noffsinger 1976), soil texture (Fisher and Anthony 1980), and soil moisture (Haines and Gier 1951; Miller 1964). With regard to the latter two variables, Miller (1964) and Best (1973) have presented evidence indicating that soil texture is a primary factor limiting the distribution of some fossorial mammals but soil moisture content may also be of importance (Miller 1948). The extent to which these soil properties influence the distribution and abundance of pine voles is presently unclear. Similarly, pine vole response to soil temperature remains unexplored. Thus, in this study we examine the influence of soil texture, moisture, and temperature on nest site selection and burrowing activity of the pine vole, Microtus pinetorum.