AWWA ACE91160

Unregulated ballast water discharge associated with European commercial ship traffic in the Great Lakes has been implicated in the successful introduction of several species during the 1980s. These species include a filter feeding bivalve mollusc, the zebra mussel, Dreissena polymorpha. Dreissena, first discovered in Lake St. Clair in 1988, is well-known as a significant biofouling organisms in Europe, and in many aquatic systems, is the dominant benthic species. Assessing potential impacts of Dreissena on native communities and promulgating successful control strategies requires a thorough understanding of its basic life history patterns in its new environment. This paper presents data describing baseline life history data on a Dreissena population recently established in western Lake Erie. Annual cycles of gametogenesis, seasonal abundance of planktonic veliger larvae, settlement patterns of post-planktonic juveniles onto artificial substrates, and their relationships with seasonal fluctuation of water temperature in western Lake Erie are described, as well as seasonal patterns of body mass and metabolism which serve as indicators of stress induced by spawning and/or fluctuating thermal environments.