Editor's Note

From January 31, 1991 (update #6)

During 1990, the following samples were analyzed as part of the Wisconsin Sea Grant Zebra Mussel Watch: in Wisconsin waters of Lake Michigan 214 harbor substrate samples, 176 harbor plankton tows and 286 water intake samples; in Wisconsin waters of Lake Superior 168 harbor substrate samples, 110 harbor plankton tows and 58 water intake samples. No zebra mussels were found in any of the samples collected from Wisconsin waters of Lake Michigan. Zebra mussels were found in Superior Harbor plankton tows on Aug. 21 at densities of 46-51 per cubic meter, and Aug. 28 at densities of 40 per cubic meter. Recently settled zebra mussels were found on Superior harbor substrates on Aug. 28 (one mussel, 0.76 mm long), Sept. 6 (three mussels, 0.44-0.52 mm long), Sept. 24 (five mussels, 1.08-2.28 mm long) and Oct. 5 (10 mussels, 0.88-2.0 mm long). Preparations for conducting a similar sampling program during 1991 are under way. Wisconsin Sea Grant also plans to offer training in the identification of zebra mussel larvae and adults for those interested in more frequent intake monitoring.

ID: 19910131-1.

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.