Horses on the Menu: Patterns and Drivers of Free‐Ranging Horse Consumption by Iberian Wolves

Introduction In the Iberian Peninsula, autochthonous breeds of mountain ponies, raised in a traditional free‐ranging system, can comprise most of the wolf diet, leading to significant economic losses and conflicts. Nevertheless, drivers of horse consumption remain poorly understood. Aims This review quantifies the role of free‐ranging horses in Iberian wolf diet and factors influencing horse consumption, through a meta‐analysis to: (1) assess general patterns of wolf diet in areas with/without free‐ranging ponies; (2) investigate how free‐ranging horse consumption affects other prey consumption; and (3) identify key drivers influencing free‐ranging horse consumption. Methods We conducted a systematic literature review of 37 publications, comprising 137 annual studies and 104 sampling sites. Results and Discussion Overall, horses are the third most consumed species, following goats and wild boar. Free‐ranging horses are, on average, the most common wolf prey, surpassing wild and domestic prey. Moreover, free‐ranging horse consumption is higher than domestic ungulates at lower altitudes, with smaller wolf packs and lower domestic prey diversity. Compared to wild ungulates, horse consumption is higher with larger wolf packs and higher human density. In relation to occasional prey species, free‐ranging horses are more consumed at lower altitudes and with greater wild and domestic prey diversity. In sampling sites without free‐ranging horses, we observed a stronger effect of horse abundance in the level of their consumption by wolves. Conclusion Our findings suggest free‐ranging horse consumption is restricted to NW Iberia and determined by prey availability, topography and human density. When available, free‐ranging horses are more consumed than other species, acting as a buffer to reduce predation on more valuable livestock, which highlights their important ecological role.