Feeding ecology of generalist consumers: a case study of invasive blue catfish Ictalurus furcatus in Chesapeake Bay, Virginia, USA

摘要: Globally, invasive species cause extensive economic damage and are a major threat to biodiversity. Generalist particularly dangerous invaders, as they can thrive in degraded habitats endure environmental stochasticity, often outcompeting more specialized native taxa. Blue catfish Ictalurus furcatus were first introduced into the Chesapeake Bay during 1970s, now form dense populations several tidal rivers. Despite being labeled invasive, feeding ecology of this is largely unknown. We used stratified random design collect stomachs from 16,110 blue freshwater, oligohaline, mesohaline segments James, Pamunkey, Mattaponi, Rappahannock Rivers. Indices diet breadth omnivory reveal that generalist omnivores with some highest breadths ever observed an estuarine fish species, while trophic level calculations demonstrate mesopredator occupying lower levels than previously claimed. Cumulative prey curves revealed large numbers necessary adequately characterize catfish, thus previous descriptions should be considered caution. feed primarily on aquatic vegetation Asian clams, though economically-valuable crab Callinectes sapidus also consumed regularly. While per capita impact imperiled appears low, could still substantial due high population densities.