Essential Ecology of Scavengers

This chapter discusses the essential ecosystem function of microbial decomposition and carrion consumption by scavengers. Decomposers are single-celled, saprophytic or saprozoic organisms, including bacteria, which feed extracellularly on dead material on-site. Scavengers are multicellular organisms, including both invertebrates and vertebrates, which feed on the fragments of carcasses, either on-site or elsewhere. The ecological actions of decomposers and scavengers as elemental recyclers serve to recapture and supply the raw materials that other ecological entities, including plants and consumers, need to maintain the energetic processes of primary and secondary productivity necessary to sustain the long-term continuity of ecological systems. Although many carnivorous vertebrates are facultative scavengers that sometimes feed on carrion, the world's vultures are the only truly obligate vertebrate scavengers, species that feed almost entirely on carrion and that require carrion for their livelihoods.