Mussel Densities Increase Over Winter at Michigan and Illino

is Power Plants

From April 30, 1991 (update #7)

Zebra mussel densities increased on the intake structure at the Consumer's Power Company Saginaw, Mich., power plant since similar inspections last fall, when only a few mussels were found on cement settling blocks. According to Senior Environmental Advisor Ron Fobes, concentrations of about 25 mussels per square yard were found in early April - the largest infestation observed yet in Lake Huron. Enough mussels were removed from the plant to fill a 55-gallon drum. Ninety to 95 percent of the mussels found were 1/2 to 3/4 inches (1-2 cm) in length; a few were even larger. A similar observation was made at the Commonwealth Edison power plant in Waukegan, Ill. According to Senior Environmental Biologist Harry Bernhard, tiny zebra mussels (0.08-0.16 inches, 2-4 mm) long were found in early March on concrete substrates that were bare when last examined in November. The substrates were located in the plant's intake canal.

ID: 19910430-4.

The Zebra Mussel Update was a 4- to 8-page quarterly national newsletter published by the University of Wisconsin Sea Grant Institute from May 1990 through May 1997. The ZMU documented the spread of the zebra mussel -- an exotic nuisance mussel -- through North America's freshwater environments, especially the Great Lakes, and on efforts to control it.