IMPACTS OF ZEBRA MUSSEL ON WALLEYE (STIZOSTEDION-VITREUM) REPRODUCTION IN WESTERN LAKE ERIE

A walleye spawning shoal (Sunken Chicken Reef) in western Lake Erie wa s sampled during the spring of 1990 and 1991 to assess the abundance o f the zebra mussel Dreissena polymorpha and to determine its impact on walleye reproduction. Mussel abundance ranged from 76 500/m(2) at 1.5 m depth to 344 300/m(2) at 4.5 m depth at the shoal (1990). Despite t he almost total coverage of spawning beds walleye continued to spawn a t the shed, with no apparent effect of the mussels on egg deposition, egg viability, and interstitial dissolved oxygen. Although preinvasion data for walleye egg deposition are not comparable to data from this study, deposition appears adequate based on good indices of recruitmen t of young-of-the-year walleye derived from resource agency trawling d uring 1990 and 1991. Thus there appears to have been no adverse impact s of zebra mussel on walleye reproduction in western Lake Erie during 1990 and 1991.