Grey wolf (Canis lupus) predation on livestock in relation to prey availability

Abstract

1.Conflict between humans and large carnivores hinders carnivore conservation worldwide. Livestock depredations by large carnivores is the main cause of conflict, triggering poaching and retaliatory killings by humans. Resolving this conflict requires an understanding of the factors that cause large carnivores to select livestock over wild prey. Individual studies to date report contradictory results about whether wild prey density affects livestock depredation by large carnivores.2.We carried out a systematic review of grey wolf (Canis lupus) dietary preferences. We reviewed and analysed 119 grey wolf dietary studies from 27 countries to determine whether wild prey or livestock density affects grey wolf dietary selection.3.We also assessed whether there are traits that predispose species to be preyed upon (body size, group size, defence mechanisms, speed), and whether livestock management is a factor that affects selection of livestock by grey wolves.4.Overall, wild prey (65% of the total frequency of occurrence in all reviewed grey wolf diet studies) was selected for even when livestock was abundant. The average proportion of biomass percentage in grey wolf diets was 13% for livestock and 19% for wild species.5.Wild prey species in possession of defence mechanisms (horns, antlers, spikes, and fangs), with high body weight and present in high density were more likely to be depredated by grey wolves.6.Even when prey abundance significantly affected selection of wild prey, livestock predation was much lower considering their substantially higher density. Areas where livestock were left to graze freely in small numbers (<20 individuals/km2) were more vulnerable to grey wolf attacks.7.Our results suggest that the adoption of attack prevention measures on pastures and the increase of wild prey abundance could reduce depredation on livestock by grey wolves, and in turn, provide better opportunities for coexistence between humans, grey wolves and livestock.