Filter-feeding Asian carp (bighead carp, Hypophthalmichthys nobilis, and silver carp, Hypophthalmichthys molitrix) threaten to invade Lake Michigan and other Great Lakes through the Chicago Sanitary and Ship Canal and through introductions via bait use or the release of fish from live markets. These carp consume plankton, the base of the pelagic food web, and could disrupt a critical food source for larval and adult fish currently inhabiting the lakes. However, it is not clear that Asian carp, which are usually found in productive habitats, could survive on the relatively sparse plankton typical of most of the Great Lakes. Respirometry, mesocosm growth studies, and bioenergetic models were used in this study to evaluate the potential for growth and successful establishment by Asian carp introduced into the Great Lakes. Respiration, a key component in bioenergetic models, was measured for >130 bighead and silver carp over a range of body sizes and environmental temperatures in both static and flowing-water respirometers. The respiration data were incorporated into standard bioenergetic models that calculated basic energy requirements of the carp. These requirements were then compared to planktonic food resources to predict when and where Asian carp could grow and survive in the Great Lakes. The modeling results and mesocosm growth experiments suggest that filter-feeding Asian carp will be unable to colonize most open water regions within the Great Lakes because of limited plankton availability. Productive embayments and wetlands are more likely to support Asian carp growth, and resource managers should focus monitoring and preventative efforts there.
|Name||INHS Technical Report 2008|