Abstract
We propose the integration of different non-invasive sampling methods to the study of predator-prey interactions. We analyzed the diet of the wolf (Canis lupus) to point out its elective prey and we investigated its spatial and temporal interactions with prey species from December 2012 to November 2014 in the Ligurian Alps (Southern Alps, Italy). In this area, the wolf is the only large predator, and there is a rich wild ungulate community consisting of four species. Our analyses showed that the most consumed species by wolves were the wild boar (Sus scrofa) and the roe deer (Capreolus capreolus). To successfully hunt these species, wolves need to share their spatial range, searching for them in the most suitable habitat types and in the periods of the diel cycle during which they are mainly active. Fallow deer (Dama dama) and chamois (Rupicapra rupicapra) consumption was low, and wolves showed also relatively low overlap with these species. Our results suggest that wolves might be firstly specialized on wild boar predation, as they showed substantial spatial and temporal overlap with this species, and secondly on roe deer predation, especially during the denning season when they probably take advantage of the presence of fawns.
Acknowledgments
We thank A. Biondo, G. Cristiani, and F. Zucca for their fieldwork collaboration. P. Thomas kindly revised the English language improving the clarity of the manuscript. Two anonymous reviewers provided helpful comments to the draft of the manuscript. The collection of data was supported by the project “Il Lupo in Liguria” (2012–2014), funded and promoted by the Regional Administration of Liguria (ROP/ ERDF funds) and coordinated by the Antola Regional Park.
Appendix
Variables used to assess preference or avoidance for different habitat types by the wolf and wild ungulates in the Ligurian Alps.
| Habitat | Name | Description |
|---|---|---|
| Urban areas | Urb | Villages, industrial areas, transport units, artificial and urban parks |
| Broad-leaved forest | BF | |
| Coniferous forest | CF | |
| Mixed forest | MF | |
| Pastures | Pas | Pastures and natural grasslands |
| Cultivated lands | Cul | Arable lands and permanent crops |
| Sclerophyllous vegetation | Scl | |
| Scrublands | Shr | |
| Transitional woodland-shrub | W/S | Areas with sparsely wooded vegetation and ecotonal areas |
| Water bodies | Wat |
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