Invasive Mussel Control Science: Dreissenid Mussel Growth in Lake Ontario

Science Center Objects

USGS scientists worked with the National Oceanic and Atmospheric Administration (NOAA) to monitor growth of invasive zebra mussels (Dreissena polymorpha) in Lake Ontario with the goal of improving understanding on the effects these mussels have on the Lake food web.

Zebra Mussels, Dreissena polymorpha

(Credit: John Manier. Public domain.)

Dreissenid mussels can have profound effects on the ecosystems they invade. They primarily consume phytoplankton and can reduce phytoplankton biomass significantly following invasion. This project quantifies the rate of dreissenid mussel growth and mortality at various depths and times in Lake Ontario to compare to other places within the Great Lakes Basin.  USGS Lake Ontario Biological Station’s vessel, staff and scientists provided the vessel and laboratory platforms and assisted NOAA’s Dr. Asheley Elgin in conducting the experiment in Lake Ontario. Structures were anchored to the lake bottom that contained measured and individually marked dreissenid mussels in mesh cages.  These ‘pods’ remained on the lake bottom at depths of 90, 45, and 20 meters for approximately one year. Upon retrieval, mussels were removed from cages and analyzed to calculate the percent mortality and estimate both a multi-mussel estimates and individual estimates of change in shell length, mussel biomass and condition. This is the first work in Lake Ontario to estimate the rate of dreissenid mussel growth and will greatly improve understanding of the effects of dreissenids on the Lake Ontario food web.



  • Understanding the mechanisms and the extent to which invasive species impact Great Lakes food webs helps management design effective restoration actions.



  • National Oceanic and Atmospheric Administration (NOAA)