Variation in the diet of the red fox (Vulpes vulpes) in mountain habitats: Effects of altitude and season

The diet of red fox was studied on the basis of faecal analysis (2242 specimens) in mountain habitats. Three different areas of the Šumava Mts. (SW Bohemia, Czech Republic) were examined during the growing and non-growing seasons in 1998–2008. Related taxa were pooled, merging similar items into 17 groups for subsequent analysis. Patterns of food composition were interpreted using Principal Component Analysis. The diet of the red fox in mountain habitats comprises a broad spectrum of items, including big ungulates (the red fox makes use of carcass), other vertebrates, various invertebrate species, fruits, and also indigestible items. Principal components reflected the seasonal pattern in food composition (56.7% of variation in taxonomic groups among the areas and seasons) as well as altitudinal gradient (24.0% of this variation). We refer to proportional increase of Carnivora, Reptilia, Amphibia, earthworms, Mollusca, fruits, Coleoptera and other Insects in growing season compared with non-growing season at the expense of decrease in proportion of Rodentia, Artiodactyla and galliform birds. The higher occurrence of Lagomorpha, fishes, plants and indigestible items in the diet consumed in the foothills reflects their wide supplies in the urbanised areas or their functioning as prey alternatives under food conditions in lower altitudes.