Carnivore predation on livestock often leads people to retaliate. Persecution by humans has contributed strongly to global endangerment of carnivores. Preventing livestock losses would help to achieve three goals common to many human societies: preserve nature, protect animal welfare, and safeguard human livelihoods. Between 2016 and 2018, four independent reviews evaluated >40 years of research on lethal and nonlethal interventions for reducing predation on livestock. From 114 studies, we find a striking conclusion: scarce quantitative comparisons of interventions and scarce comparisons against experimental controls preclude strong inference about the effectiveness of methods. For wise investment of public resources in protecting livestock and carnivores, evidence of effectiveness should be a prerequisite to policy making or large-scale funding of any method or, at a minimum, should be measured during implementation. An appropriate evidence base is needed, and we recommend a coalition of scientists and managers be formed to establish and encourage use of consistent standards in future experimental evaluations.

A reduction in the loss and waste of human food is a global issue for addressing poverty and hunger in poorer nations, and for reducing the environmental footprint of the agriculture sector. An emerging issue, however, is that food wasted by humans is often accessible to wildlife, affecting wildlife ecology and behaviour, as well as ecological processes and community dynamics. Here we highlight the extent of such impacts, drawing on examples from mammalian predators and other taxonomic groups. We then develop two conceptual models. The first shows how wildlife access to food waste can exacerbate human-wildlife conflicts. The second highlights that when food waste is removed, the effects on wildlife and ecosystem processes should be monitored. The conceptual models are important when considering that large quantities of food waste are intentionally and unintentionally provided to wildlife around the world. We conclude there is an urgent need to change the way people currently manage the food we produce.