Sizing up the ecological role of sharks as predators

Abstract

The decline of predators in a variety of ecosystems has transformed community structure through mesopredator release and trophic cascades. Elasmobranch fishes, one of the earth's most ubiquitous and diverse clade of predatory species, provide a model group for defining marine predator roles. We consider whether the ecological predatory role of sharks is adequately defined by terrestrial-derived notions of apex- and mesopredation. Indeterminate growth and ontogenetic diet shifts may mean species-level classification of predatory roles is inadequate. We propose that examining the trophic level and body size of species might be the most pragmatic and informative way to define the ecological roles of predators. © Inter-Research 2014.