The importance of livestock in the diet of Mexican wolf Canis lupus baileyi in northwestern Mexico

Abstract

The reintroduction of the Mexican wolf in the wilds of northwestern Mexico has allowed us to address its trophic ecology and elucidate conflicts with livestock producers: their main mortality factor. Our objective was to determine the feeding habits of wolves in Mexico, as well as the quantity and frequency of livestock predation in relation to seasonal and individual variables, through the analysis of genetically identified scats. During 2012–2022 we collected 1171 Mexican wolf scats. We extracted and sequenced DNAm and identified individuals and their sex using microsatellite analysis. We washed the scat and separated the undigested components for taxonomic identification. We estimated the frequency of prey items, the biomass it contributed to the diet, and compared prey consumption between sexes and between the birth and dispersal seasons. We constructed generalized linear models to identify the relationship between livestock presence in the diet and dietary prey richness with respect to environmental and individual variables. We identified 68 wolves that had consumed 30 species of vertebrates. Of these, white-tailed deer (36.12%), diversionary feeding (22.79%), and cattle (25.56%) had the highest contribution to biomass. The ingestion of items was independent of the sex of the wolves but was dependent on the season. The presence of deer and diversionary feeding decreased the likelihood of cattle being ingested but also decreased the richness of items of wild species in the wolf diet. Wolves in northwestern Mexico fed mainly on large prey available in the reintroduction area, including livestock. As wolves consume livestock, it increases the risk of retaliatory actions from ranchers. Our results serve as a basis for the implementation of strategies to reduce human–wolf conflicts and set a baseline for coexistence in northwestern Mexico.