Yahara Lakes Most Unwanted Aquatic Hitchhikers
The zebra mussels (Dreissena polymorpha) and quagga mussels (Dreissena rostriformis bugensis) are tiny—1/8-inch to 2-inch—bottom-dwelling mussels native to Caspian and Black Seas. They were brought to the Great Lakes in the ballast water of ocean-going ships. The zebra mussel takes its name from its striped shell. Zebra mussels were introduced into the Great Lakes system in 1985 or 1986 and first turned up in Lake St. Clair.