Green Glossary: Zebra Mussel

Technically speaking, the zebra mussel is a freshwater Eurasian lamellibranch mollusk (Dreissena polymorpha). The National Atlas offers more: "Zebra mussels get their name from the striped pattern of their shells, though not all shells bear this pattern. They're usually about fingernail size but can grow to a maximum length of nearly 2 inches. Zebra mussels live 4 to 5 years and inhabit fresh water at depths of 6 to 24 feet. A female zebra mussel begins to reproduce at 2 years of age, and produces between 30,000 and 1 million eggs per year. About two percent of zebra mussels reach adulthood."

Why is all this relevant to greenies? Well, this marine shellfish was first discovered in the Great Lakes of the United States in 1988 and is believed to have arrived in North America by being carried in the ballast water of a cargo vessel and, according to the Ecology Dictionary, "Since the first discovery of this exotic species, they have spread rapidly through North American surface waters, particularly throughout the Great Lakes and Mississippi River basins and their navigable tributaries. As of March 1996, zebra mussels were resident in nineteen states and two Canadian provinces. Zebra mussels can cause severe fouling of municipal drinking water, electric power generation, and industrial water systems; they are also harmful to aquatic ecosystems, boating and navigation, agricultural irrigation equipment, aquacultural equipment, and recreation beach use."