ABSTRACT
Responses to the zebra mussel invasion followed an “event sequence” typical of most unintentionally introduced exotic species to the Great Lakes: initial release, discovery, taxonomic verication, information-search media reports, scientic presentation/publication, expert committee(s) establishment, distribution and containment, outreach and education, abatement and adaptation, ecosystem impact monitoring, acceptance as naturalized; then wait for the next invasive species. However, the “abatement and adaptation” event was the most costly that the Great Lake’s community had ever experienced from an aquatic exotic species. Zebra mussel impacts initially occurred in municipal and industrial facilities taking raw water for domestic, cooling, and process use. Companies and government agencies that operated multiple facilities such as Ontario Ministry of the Environment’s water treatment plants, Ontario Hydro’s electric-generating stations, and Detroit Edison’s electric-generating stations had the advantage of deep nancial pockets, biological-knowledgeable staff, and engineering expertise that were able to quickly establish monitoring and abatement programs to prevent severe impacts. Consequently, zebra mussels had the largest impacts on smaller, singlefacility companies, severely restricting and interrupting water supplies to water treatment facilities in Monroe and Bay City, Michigan; Ford’s Engine Plant in Windsor, Ontario; and a food processing plant in Wheatley, Ontario. Biofouling impacts on facilities drawing water from the Great Lakes declined rapidly after the rst year, as facility operators put monitoring and abatement programs into place.
