DNA Metabarcoding Reveals Wolf Dietary Patterns in the Northern Alps and Jura Mountains

Understanding predator-prey interactions is crucial for wildlife management and human-wildlife coexistence, particularly in multi-use landscapes such as Western Europe. As wolves (Canis lupus) recolonize their former habitats, knowledge of their diet is essential for conservation planning and public acceptance. However, data of such regions is so far scarce, in particular for the Alpine region and the Jura Mountains. As opportunistic hunters, wolves adapt their diet to the local prey structure, suggesting that abundant wild ungulates are the main prey source. We also expect diet composition to be influenced by region, season and social status. DNA metabarcoding has emerged as a powerful tool in ecological research, offering high-resolution insights into dietary composition, yet its application in carnivores remains limited. Using a DNA metabarcoding approach, we analyzed 698 wolf scat samples collected in Switzerland from 2017 to 2024. We found red deer (Cervus elaphus) was the dominant prey in most areas, and together with roe deer (Capreolus capreolus) and chamois (Rupicapra rupicapra), accounted for 80.8% of the retrieved sequences. We found similarities in prey selectivity between the Alps and the Jura Mountains, but found significant differences across seasons and between pack and non-pack wolves. This study provides the first detailed dietary analysis of wolves in the Northern Alps and Jura Mountains, offering critical insights for wildlife management. Our findings highlight the importance of wild ungulates in wolf diet and underscore the value of non-invasive DNA approaches as a reliable conservation and biomonitoring tool.