Dr. Bill Harman, Director of the State University of New York (SUNY) at Oneonta Biological Field Station in Cooperstown, New York, holds a flip-flop recovered from Otsego Lake and covered with invasive zebra mussels.
Zebra mussels (Dreissena polymorpha) are freshwater bivalves found in lakes, rivers, streams and reservoirs. Native to Europe, zebra mussels were found in the Great Lakes region in 1988 and later discovered in the upper Susquehanna River in 2002. Since then, the invasive mussel has spread further into the Chesapeake region’s rivers and streams. In 2011, the mussel was spotted for the first time in the Eastern Shore’s Sassafras River. And in 2015, two watermen found zebra mussels colonizing on their fishing gear in the Susquehanna Flats.
Efficient filter-feeders, zebra mussels can remove a lot of plankton—an important food source for other critters—from the water. They also attach themselves to native mussels and to manmade structures, clogging intake pipes and encrusting boat hulls and buoys. Scraping, power-washing and chemical treatments can be used to control zebra mussels, but once a population has been established, it can be almost impossible to eradicate.
To prevent the spread of zebra mussels and other invasive species, make sure boat hulls, trailers and other equipment are thoroughly cleaned before moving them to a new body of water.
Image by Will Parson