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

A walleye spawning shoal (Sunken Chicken Reef) in western Lake Erie was sampled during the spring of 1990 and 1991 to assess the abundance of 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 the almost total coverage of spawning beds walleye continued to spawn at 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 recruitment of young-of-the-year walleye derived from resource agency trawling during 1990 and 1991. Thus there appears to have been no adverse impacts of zebra mussel on walleye reproduction in western Lake Erie during 1990 and 1991.