Species Information: Zebra Mussels
In Louisiana, these little mollusks have moved into the Mississippi River through migration from the Great Lakes. Native to the Caspian Sea area of Eastern Europe, they were accidentally transported into Lake St. Clair in 1986 by ocean-going cargo vessels. By 1989, they had established populations in several of the Great Lakes, and eventually they changed the ecosystems in some of them.
Zebra mussels, about the size of a thumbnail, are filter feeders. During their juvenile stage, they attach to hard surfaces such as pilings, boat hulls, rocks, pipes or even each other and settle down to consume nutrients from the water for the rest of their lives. Attachment is made with an extremely strong substance called a byssal thread.
They are too small for humans to eat and have only one natural predator in Louisiana (freshwater drum). Diving ducks are also known to eat them.
Zebra mussels are small bivalves that cause big problems in our rivers and lakes.