Fungus Consumption by the Southern Red-backed Vole (Clethrionomys gapperi) in the Southern Appalachians

Abstract

We examined fungus consumption (mycophagy) by the southern red-backed vole, Clethrionomys gapperi, at 4 sites within two mixed mesophytic forests in the southern Appalachians in 1996 and 1999. Fecal pellet analysis was used to determine the fungi consumed by 30 voles. Overall mean spore frequency, measured as the proportion of fields of view that contained a spore, was 0.68, whereas mean frequency of plant material was 0.57 and frequency of insect material was less than 0.04. Voles primarily consumed 5 types of fungi, consisting of 4 genera and Glomalean spores, although 29 unidentified spore morphotypes were also observed. Among identified spores, mean frequency of Melanogaster was greatest, followed by Coprinus, Elaphomyces and Glomalean spores. Spores of Hymenogaster were least frequent. The consistent presence of spores in fecal pellets suggests that fungi are an important food item and that C. gapperi may be an important disperser of fungal spores. Compared with previous studies, our research supports the notion that C. gapperi is a fungal generalist and analysis of vole diets may be useful for assessing the availability of fungi for other, more specialized small mammal mycophagists such as the northern flying squirrel, Glaucomys sabrinus.