Feeding ecology of the red fox in the Soana Valley, Gran Paradiso National Park

Abstract

Red fox (Vulpes vulpes) feeding ecology has been frequently studied in Europe, and in particular in the alpine region. However, in few areas this subject has been thoroughly investigated as in the Gran Paradiso National Park (NW Italy), where the food habits of this generalist species have been repeatedly analyzed since the 1950s, giving today the opportunity of identifying long-term variations in red fox diet. After the last report on this carnivore’s diet in the GPNP (1990s), the protected area has been colonized by new potential prey (roe deer, red deer and wild boar) and by a new possible competitor for food resources (wolf). Therefore, we tried to evaluate red fox ecological responses to these colonization processes, focusing in particular on its feeding behavior. We investigated the food habits of this species in the Soana Valley, the sector of the GPNP where the occurrence of roe deer, red deer, wild boar and wolf proved to be more stable and abundant in the last years, comparing our results with those reported in the previous studies carried out in the park. Ungulates, and in particular alpine chamois, were the main food resources in the study area, followed by fruits, insects and small-mammals. Diet composition and trophic niche breadth significantly changed among seasons, mainly due to the effects of snow cover on prey availability. The comparison with previous studies carried out in the GPNP highlighted the capability of the red fox to rapidly adapt to use new available prey (especially roe deer), while the ecological interactions with the wolf are still unclear, needing further research.