- Contact information
For information on Lakes in Wisconsin, contact:
- Wisconsin DNR Lakes
Division of Water
Bureau of Water Quality
- Aquatic Invasive Species Contacts
Zebra Mussel - Bark River - Nagawicka Lk to Applebecker Millp.
- Date First Found
- Latitude and Longitude
The zebra mussel (Dreissena polymorpha) is a tiny (1/8-inch to 2-inch) bottom-dwelling clam native to Europe and Asia. Zebra mussels were introduced into the Great Lakes in 1985 or 1986, and have been spreading throughout them since that time. They were most likely brought to North America as larvae in ballast water of ships that traveled from fresh-water Eurasian ports to the Great Lakes. Zebra mussels look like small clams with a yellowish or brownish D-shaped shell, usually with alternating dark- and light-colored stripes. They can be up to two inches long, but most are under an inch. Zebra mussels usually grow in clusters containing numerous individuals.