Wolves cause substantial losses to livestock and other domestic animals globally and therefore are strongly disliked by local people. Global reviews of published studies are needed to identify and apply the most effective interventions of livestock protection.
We used the literature analysis to quantify the effectiveness of livestock protection interventions, compare it across interventions, and find the best interventions for wider applications. The most effective were fencing (electric fences, electrified fladry, night shelters), deterrents, calving control and herding.
Effectiveness was measured as the relative risk (RR), which was transformed to the percentage of damage reduction (DR) for easy interpretation. The formula is simple: DR = (1-RR)*100%. RR is the probability of damage when an intervention is applied divided by the probability of damage without an intervention. The formula of the relative risk is also simple: RR = (nt/Nt)/(nc/Nc), where nt is the number of losses (livestock, beehives, etc.) with the intervention, Nt is the total number of the resource with the intervention (livestock, beehives etc.), nc is the number of losses without the intervention and Nc is the total number of resource without the intervention. The letter "t" stands for treatment (with intervention) and "c" for control (without intervention).
Interventions are effective when RR is less than 1, ineffective at RR = 1 and counter-productive (interventions produce more damage) when RR is higher than 1. Interventions are most effective when RR = 0, i.e. no losses are inflicted when the intervention is applied (nt = 0).
Literature search, data collection and analysis
CONDITIONS OF SUCCESS
Intensive search for appropriate literature
Appropriate quantification of effectiveness (e.g., correlational studies are irrelevant as they only show trends, but not causal effects)