Grazing Effects of an Exotic Bivalve ( Corbicula Fluminea ) on Hypereutrophic Lake Water

• Published in: Lake and Reservoir Management
• Main Authors: Beaver, John R., Crisman, Thomas L., Brock, Robert J.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Digital Commons @ University of South Florida 1991
• Subjects: Earth Sciences; Copepods; Rotifer
• Online Access: https://digitalcommons.usf.edu/geo_facpub/1721; https://doi.org/10.1080/07438149109354253

This preliminary study evaluates the ability of the widespread, exotic clam Corbicula fluminea to influence the characteristics of plankton in eutrophic Florida lakes. Effective clam densities of 131 m-2 and 2621 m−2 reduced chlorophyll a concentrations in hypereutrophic lake water > 60 per cent over 7 days. Clam filtration rates were estimated to be approximately 500 ml hr−1 clam−1. Zooplankton communities shifted to dominance by copepods in all treatments, although rotifer populations declined more rapidly in clam treatments. Although clams stimulated dissolved nitrogen concentrations, phytoplankton populations were reduced. Potential effects of Corbicula fluminea on plankton characteristics of subtropical lakes are discussed.