Vertebrate Scavenging on Sika Deer Carcasses and Its Effects on Ecological Processes

The impacts of sika deer on ecological communities often focus on the effects of “alive” deer, but how “dead” deer affect organisms and the environment currently receives little attention. Dead animals (i.e., carcasses) are a high-quality food resource for scavengers that provide ecosystem services, and scavenging plays an important role in ecosystem stability. Forest ecosystems in Japan have an overabundance of deer and need constant population control via culling. Consequently, the deer carcasses from natural mortalityNatural mortality and huntingHunting and/or cullingCulling by human are a large food resource for many vertebrate scavengers. In the forest ecosystem of Honshu Island, we documented a vertebrate scavenger guild that feeds on deer carcass, which is composed of six mammals and three birds. Vertebrate scavenging is widespread, and the scavenging links from carcass to vertebrate scavengers are one of the essential energy transfers in food webs. Furthermore, sika deer carcasses were consumed entirely in about 1 week; thus, vertebrate scavengers contribute ecosystem services to remove potentially infectious carcasses from ecosystems. Future carcass availability related to overabundant deer populations and their management could alter the function of the scavenging community. Considering carrion management is a critical aspect in evaluating the widespread impact of deer and their ecological processes and could lead to proper ecosystem management.