Movements of the Pine Vole (Microtus pinetorum) in Repopulating Orchard Habitat

Pine vole (Microtus pinetorum) populations cause significant damage to orchards and truck crops (e.g., Anthony and Fisher 1977, Biser 1967, Eadie 1954, Forbes 1972a). Yet their population structure and movement dynamics have received surprisingly little study (Smolen 1981). The scarcity of data may have been due in part to the former availability of Endrin as a highly effective control agent (e.g., Horsfall 1956b), but the appearance of Endrin-resistant populations (Webb and Horsfall 1967), the restrictions of use of chlorinated hydrocarbons, and the inclusion of pine voles in Integrated Pest Management programs have made the need for basic population data including immigration and emigration more acute. For example, demographic and movement information are universal components ofIPM programs, because management of populations is usually, and appropriately, based on demographic expectations, such as: how rapidly can pine vole populations increase? What densities can they achieve? How quickly do they recolonize depopulated areas? These are fundamental questions that require well-controlled field studies with specific aims. Other studies that bear upon the relationship of demographics and movement provide important background but fail, because of either design or analysis, to directly answer the above questions. See for example: Gentry (1968), VanVleck (1968), Gettle (1975), Gourley (1983), Renzullo (1983), Fitzgerald and Madison (1983)