11-Quagga and Zebra Mussels

Quagga mussel (Dreissena rostriformis bugensis) and zebra mussel (D. polymorpha) are non-native mussels that have exponentially expanded their distribution in the U.S.  

 National Park Service

National Park Service

These invasive mussels have  exponential  reproductive growth and no natural predators in North America. One female can produce 1 million eggs in a spawning event. Assuming only 10% of those survive there would be 10 septillion mussels after 5 years.


Invasive mussels are among the most economically damaging aquatic organisms to invade the U.S. The ability of mussels to attach to solid objects like water intake pipes, propellers, boat hulls, dock pilings, submerged rocks and even other aquatic animals increase impacts of this species. These mussels can clog filters, pipes, and pumps in hydropower and irrigation systems, and threaten native invertebrates, fish and wildlife.  


These two mussel species have been reported infesting waters of 33 states which includes numerous rivers and more than 750 small lakes and reservoirs. Much of this recent dispersal is being attributed to recreational activities such as boating and fishing (USGS) .