Predicted Biomass and Food Web Impacts of Bigheaded Carp across Great Lakes Habitats

Session: Poster session

Ed Rutherford, NOAA Great Lakes Environmental Research Laboratory, [email protected]
Hongyan Zhang, CIGLR, University of Michigan, [email protected]
Yu-Chun Kao, Michigan State University, [email protected]
Doran Mason, NOAA Great Lakes Environmental Research Lab, [email protected]
Ali Shakoor, Wayne State University, [email protected]
David Lodge, Cornell University, [email protected]
Lindsay Chadderton, The Nature Conservancy, [email protected]

Abstract

Bighead and Silver Carp (collectively, bigheaded carps ‘BHC’) are highly invasive planktivorous fish that threaten to invade and impact Great Lakes food webs. We used the Ecopath with Ecosim food web model to simulate potential BHC biomass and food web impacts across Great Lakes habitats that vary in productivity, prey and predator biomass, and species composition. For each lake habitat, we standardized initial BHC biomass at 2% of the habitat’s total fish biomass, and ran 120-year simulations under variable levels of prey and predator availability to BHC, and variable BHC production/biomass ratios. Results indicated that habitat productivity and community composition may affect BHC equilibrium biomass and food web impact. Across lakes, predicted BHC biomass and food web impacts were higher in more productive habitats compared to less productive habitats. Within lakes, BHC biomass was higher in more productive habitats but their food web impacts were lower compared to less productive habitats. BHC impacts on plankton, planktivores and piscivores were mainly negative, but neutral on benthivorous and most omnivorous fishes. Future work will incorporate new research on BHC prey dynamics in nearshore environments, and simulate potential impacts of BHC on the Lake Ontario and Illinois River food webs.

1. Keyword
biological invasions

2. Keyword
ecosystem modeling

4. Additional Keyword
food webs