Scavenging: how carnivores and carrion structure communities

Recent advances in the ecology of food webs underscore the importance of detritus and indirect predator prey effects. However, most research considers detritus as an invariable pool and predation as the only interaction between carnivores and prey. Carrion consumption, scavenging, is a type of detrital feeding that should have widespread consequences for the structure and stability of food webs. Providing access to high-quality resources, facultative scavenging is a ubiquitous and phylogenetically widespread strategy. In this review, we argue that scavenging is underestimated by 16-fold in food-web research, producing inflated predation rates and underestimated indirect effects. Furthermore, more energy is generally transferred per link via scavenging than predation. Thus, future food-web research should consider scavenging, especially in light of how major global changes can affect scavengers.