Great Lakes Laboratory for Fisheries & Aquatic Sciences, Fisheries & Oceans Canada,867 Lakeshore Road, Burlington, Ontario, Canada. L7R 4A6.

*Corresponding author: dermottr@dfo-mpo.gc.ca

Summary

   Average benthic density and biomass were greatest in the eastern basin of Lake Erie. Dreissena dominated all areas while the mayfly Hexagenia was common in the west basin. Quagga mussels ( D. bugensis) represented 90 to 100 % of the collected mussels; while Oligochaetes, Pisidium and Chironomus dominated the fauna in the central basin.
Except for the mayflies, benthic density and biomass of the inmvertebrates decreased in the west basin between 1993 and 1998, while dreissenid biomass increased in the central and east basins. No specimens of the amphipod Diporeia were collected in Lake Erie during1998.