Food Habits of Pacific Marten From Scats In South-Central Oregon

Abstract

Quantifying prey taken by Pacific Marten (Martes americana caurina) helps to understand local habitat requirements of the species. We collected 250 scat samples associated with at least 53 marten in a salvage-logged Lodgepole Pine (Pinus contorta)-Bitterbrush shrub (Purshia tridentata) forest in south-central Oregon. The frequency of occurrence of food items included 98.0% mammals, 36.0% arthropods, 23.2% birds, 9.2% plants, 2.0% hares and rabbits, and 0.8% reptiles. Among mammals, 72.4% were vole-sized and 47.2% squirrel-sized. Chipmunks (Neotamias spp., 27.6%) and ground squirrels (Spermophilus spp., 28.0%) had the highest occurrence by size group, respectively. Frequency varied little between summer and winter. Male marten preyed on a greater proportion of mice (Peromyscus spp.) than females, especially in summer, and in winter females preyed on a greater proportion of voles (Microtus spp.) than did males. Female marten also preyed on a greater proportion of birds in winter than did males, whereas males had a greater proportion in summer. We compare our findings with a concurrent study in northeastern Oregon and discuss the importance of slash piles from the indirect evidence in the frequently logged forest type to help inform habitat management of the species and prey.