Zebra mussel is a freshwater, Eurasian shellfish that is a major pest in North America. In parts of the Great Lakes, millions of zebra mussels clog pipes that provide water for drinking, irrigation, and industrial uses. They also cover boat bottoms, piers, fish traps and nets, and marker and navigation buoys. In addition, zebra mussels cover native freshwater mussels and smother them, resulting in the elimination of native mussels from some regions. The explosive growth of zebra mussels may threaten the food supply of many species of fish and shellfish native to the Great Lakes.
Zebra mussels grow to about 2 inches (5 centimeters) long, and many have stripes. Each mussel attaches to a hard surface by producing sticky tufts of byssal threads. Zebra mussels feed on tiny floating organisms called plankton. The mussels themselves are eaten by several species of fish and diving ducks.
Zebra mussels are native to the area around the Caspian and Black seas. They were first found in North America in 1987. Their larvae (young) had been unintentionally released into the Great Lakes in ballast water (the water kept in the hold of a ship to keep the vessel stable). By 1994, zebra mussels had spread to all the Great Lakes, the Hudson and Mississippi rivers, and the Arkansas River as far west as Oklahoma. Biologists believe they eventually will spread to more than half the lakes and rivers of North America.
See also Invasive species; Mussel.
