Effectiveness of behaviour-based interventions in reducing livestock depredation by wolves (Canis lupus)

Authors: Thaana Van Dessel & Lysanne Snijders

Abstract: Sustainable coexistence between wolves (Canis lupus) and humans primarily relies on the availability of effective mitigation practices to reduce livestock depredation by wolves. As a result of wolf recovery, domestic animal losses have been rising, despite the broad implementation of both lethal and nonlethal management efforts. This growing conflict of interest between livestock activities and wolf conservation requires an evidence-based insight into the effectiveness of nonlethal livestock protection interventions. Therefore, in this systematic review, we synthesised the evidence available on the effectiveness of behaviour-based interventions in reducing livestock depredation by wolves. We systematically searched Scopus and Web of Science and screened for literature in a specialised systematic map database created by Snijders et al. (2019). We retrieved 2825 publications, of which 16 articles (and their 31 corresponding studies) were included in the review after the screening process. We used relative risk ratios (RR) and standardised mean differences (SMD) as measures of the intervention effect size and subsequently performed a metaanalysis. Our study revealed a worrying lack of published empirical evidence on nonlethal behaviour-based interventions, at least in the English language, despite their broad application in practical management efforts. Nevertheless, most interventions included in the review, particularly fladry, demonstrated high effectiveness in deterring wolves from approaching- or predating livestock and bait carcasses. The limited size of the evidence base did not allow exploration of the factors that may further moderate the effect size. Knowing these so-called effect moderators could lead to more tailor-made practical recommendations on when and where to employ which type of behaviour-based intervention. Overall, our results suggest that behaviour-based nonlethal measures could be a promising mitigation tool, provided that more research supports these findings. Therefore, we strongly recommend scientists, conservation practitioners and management authorities to collaborate and to further research nonlethal interventions, especially investigating efficacy in real depredation scenarios. A more evidence-based approach to human-wolf conflict is essential in building a viable future for wolves, livestock and pastoral activities.