Vulnerability of Juvenile Asian Carp to Predation By Largemouth Bass

Invasive bighead (Hypophthalmichthys nobilis) and silver carp (Hypophthalmichthys molitrix) have become established throughout much of the Mississippi River basin. In many areas, these two species comprise a significant proportion of the fish biomass. Despite their prevalence and potential for negative environmental impacts, to date, there has been no research regarding predator-prey interactions between Asian carp and native species. We sought to examine largemouth bass (Micropterus salmoides) predation on juvenile bighead and silver carp in relation to common native prey species. Prey species selection experiments in 2-m pools showed number of prey captures was highest for bighead carp followed by gizzard shad with lower capture rates for bluegill, golden shiner, and silver carp. Observations of prey and predator behavior were quantified in a 720-L tank to explain differences in prey vulnerability. Variation in anti-predator behavior explains relative differences in vulnerability to predation. These differences in vulnerability between bighead and silver carp may explain their differences in invasion success. The relatively high vulnerability of bighead carp and similar vulnerability of silver carp to common native prey suggests that Asian carp may serve as viable prey for native predators mitigating the potential negative impacts on the native prey community.