Seasonal prey selection by wolf in a recolonized prey-rich area

Prey selection is a key process involved in predator-prey relationships. Prey abundance is a major determinant of prey availability, in turn influencing prey selection. In multiple-prey communities, prey availability may change seasonally, which could determine switches in the ranking of their relative abundance. However, how seasonal changes in prey availability influence prey selection is still understudied. With a three-years study we evaluated the seasonal prey selection by wolf Canis lupus, in a recently recolonized coastal area of Italy, characterized by a rich prey community (i.e. composed of wild boar Sus scrofa, fallow deer Dama dama and roe deer Capreolus capreolus). Prey availability was assessed through relative abundance indices estimated through camera trapping (n= 45837 detections), through a procedure previously validated against density estimates obtained through pellet group counts. We used the Jacobs index and 95% confidence intervals to estimate seasonal prey selection (n= 1538 wolf scats). The wild boar was the most available prey in spring summer-autumn, but it was overcome by the fallow deer in winter, presumably because the high mortality imposed by predation throughout the year. Although the wild boar was the most used prey throughout the study, it was selected only in winter 2022 and in spring and winter 2023, whereas the fallow deer was selected in summer 2021 and 2022. We also found a negative correlation between the selection indices of wild boar and the fallow deer. These results suggest that the selection process by wolves was affected by ungulate abundance, emphasizing the role of complementary prey.