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Zebra mussel
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• Discovered in Oneida Lake in 1991
• Consume algae by filtering it from the water column
• Provide food for Oneida Lake fish such as lake sturgeon and freshwater drum
Zebra mussels are native to the Ponto-Caspian region (Black, Caspian, and Aral Seas) of Eurasia. They were first found in 1988 in Lake St. Clair (between Lake Huron and Lake Erie) and within five years had spread to all the Great Lakes and through the Mississippi basin all the way to Louisiana. They were first discovered in Oneida Lake in 1991. Zebra mussels arrived in the ballast water of transoceanic ships and have spread by attaching themselves to boat hulls, by unintentional transport in recreational watercraft and gear, and by natural dispersal. Zebra mussels produce larvae called veligers that are not visible to the naked eye and may be transported unknowingly in live wells or bait buckets.
Zebra mussels can grow to two inches long and have a lifespan of four to five years. Shells typically have alternating bands of tan and brown, giving them a striped appearance. However, they may occasionally appear almost completely brown, or even more rarely, entirely light colored with little striping. Oneida Lake’s zebra mussels are usually less than one inch long and their shells exhibit a range of color patterns from conspicuously striped to entirely solid-colored. Mussels attach themselves to rock, wood, steel, concrete, vegetation, and even each other. Zebra mussels are generally absent from the deepest areas of the lake (> 30 feet) due to the lack of suitable substrate. In contrast, quagga mussels (a close relative of the zebra mussel that has yet to be observed in Oneida Lake) are capable of colonizing soft substrates and deeper areas.
Each zebra mussel can filter over one quart of water each day, resulting in significant increases in water clarity. Since the establishment of zebra mussels, Oneida Lake has experienced record water clarity. The year with the clearest water on record in Oneida Lake was 1995, four years after the establishment of zebra mussels. In Oneida Lake, clearer water has allowed submerged aquatic plants to grow at depths of 15 feet or more in some locations. Since zebra mussels have become established, algal blooms that were common during the entire summer are often delayed until August or September. An unfortunate consequence of the establishment of zebra mussels in Oneida Lake has been the extirpation of three native clam species. Zebra mussels attached themselves to the shells of native clams making it impossible for them to feed efficiently.
To learn more about Zebra mussels ...
Zebra Mussel Factsheet (pdf - 1746kb)
