FOOD-HABITS AND TROPHIC NICHE OVERLAP OF THE RED FOX AND THE STONE MARTEN IN A MEDITERRANEAN RURAL AREA

The food habits of the red fox Vulpes vulpes (Linnaeus, 1758) and the stone marten Martes foina (Erxleben, 1777) were studied in a rural hil ly area in Siena county, central Italy, using faecal analysis. Both fr equency of occurrence and volume of the different foods were quantifie d. Rodents, especially Apodemus sp., were an important prey for both s pecies. Predation on poultry and game birds was nearly absent, whereas fruits and insects were seasonally taken by both species. Rosaceae fr uits were the most eaten plant item. Within this category the fox fed mainly on Malus sp. and Pyrus sp., while the marten showed a preferenc e for Rubus sp. and Sorbus domestica. Only fruits of Prunus spinosa we re eaten in comparable quantities. Beetles were well represented in th e diet of both carnivores, although they tended to concentrate on diff erent species. Grasshoppers were preyed in small quantity. The overall diet overlap of foxes and stone martens was extensive: a surprising r esult, if the different body size, locomotor adaptations and living ha bits of these carnivores are considered.