title: Community-level consequences of cannibalism.
abstract: Ecological interactions determine the structure and dynamics of communities and their responses to the environment. Understanding the community-level effects of ecological interactions, such as intra- and interspecifc competition, predation, and cannibalism, is therefore central to ecological theory and ecosystem management. Here, we investigate the community-level consequences of cannibalism in populations with density-dependent maturation and reproduction. We model a stage-structured consumer population with an ontogenetic diet shift to analyze how cannibalism alters the conditions for the invasion and persistence of stage-specific predators and competitors. Our results demonstrate that cannibalistic interactions can facilitate coexistence with other species at both trophic levels. This effect of cannibalism critically depends on the food dependence of the demographic processes. The underlying mechanism is a cannibalism-induced shift in the biomass distribution between the consumer life stages. These findings suggest that cannibalism may alter the structure of ecological communities through its effects on species coexistence.
authors.affiliation: Center for Ecological and Evolutionary Synthesis, Department of Biology, University of Oslo, Norway. jan.ohlberger@bio.uio.no
authors.forename: Jan
authors.initials: J
authors.lastname: Ohlberger
authors.forename: Oystein
authors.initials: O
authors.lastname: Langangen
authors.forename: Nils C
authors.initials: NC
authors.lastname: Stenseth
authors.forename: L Asbjørn
authors.initials: LA
authors.lastname: Vøllestad
mesh_terms: D017677:Age Distribution; D000818:Animals; D002190:Cannibalism; D004032:Diet; D020387:Food Chain; D008954:Models, Biological; D011156:Population Density; D012098:Reproduction; D013045:Species Specificity