Carrion dependence and food habits of the red fox in an Alpine area

The food habits and trophic niche breadth of the red fox (Vulpes vulpes) were studied across a wide altitudinal range in a protected Alpine area (Gran Paradiso National Park) through the analysis of 922 scats, collected monthly along fixed itineraries. Small mammals and insects prevailed in the warm season and were replaced by chamois in the cold season, as soon as carcasses became available. The overwhelming importance of the latter, clumped, nutritious and abundant resource suggests opportunistic feeding behaviour of red foxes in harsh climatic conditions. As a consequence, the trophic niche was quite narrow in winter. Accordingly, ungulate density directly influenced the use of carcasses.