Management and Control

Control Methods

Each new development in control technology represents an exciting potential technique to manage invasive mussels. As the availability of different control methods expands, managers have greater flexibility in selecting control methods that are best suited to specific water bodies and mussel populations. New control methods are investigated and tested every day; below, we provide a summary overview of the most common methods in use today.

Control Methods

Toxicant Treatments

  • Niclosamide is a compound used as a lampricide to treat invasive sea lamprey, and as a molluscicide to treat freshwater snails
  • Niclosamide is toxic to molluscs when exposed, and aquatic plants are not adversely affected by exposure
  • Bayluscide, a commercial form of niclosamide used to treat sea lamprey, is undergoing further testing by the U.S. Geological Survey for use in early detection and rapid response activities
  • Potassium chloride, also called potash, is a salt compound that is commonly found in fertilizers.
  • Potash interferes with mussels’ respiratory systems, preventing them from breathing. Potash affects both native and invasive mussels, but does not affect fish or plants
  • Biobullets® is a commercially available treatment that packages potassium chloride within an edible shell to encourage consumption by invasive mussels
  • Potash was used to eradicate zebra mussels from Millbrook Quarry, VA, in 2006 and was used in conjunction with other control methods to treat localized zebra mussel infestations in Christmas Lake, MN in 2015
  • Copper compounds may differ in specific elemental makeup, but each share copper as a main component
  • Copper compounds are toxic when ingested by mussels
  • Earthtec QZ® maintains copper as a biologically active cupric ion. This compound has been used to treat Independence Lake, MN, Ruth Lake, MN, and was used in conjunction with other control methods to treat localized zebra mussel infestations in Christmas Lake, MN in 2014 and 2015
  • Chelated copper compounds consist of copper ions bound with amino acids. A commercially available copper chelate, Cutrine Ultra®, was used to treat Lake Irene, MN, and Rose Lake, MN in 2011
  • Copper sulfate was used to treat a lake on Offutt Air Force Base in Omaha, NE in 2008 and 2009
  • Zequanox® is a compound that utilizes the killed-cells of a specific strain (CL145A) of a common soil bacterium, Pseudomonas fluorescens, as its active ingredient
  • When ingested, Zequanox® deteriorates the digestive lining of zebra and quagga mussels, causing death
  • Zequanox® is currently in use by the Tip of the Mitt Watershed Council to treat inland lakes in northern Michigan, and was used in conjunction with other control methods to treat localized zebra mussel infestations in Christmas Lake, MN in 2015

Physical Treatments

  • Benthic mats are large, dark tarps that are anchored to the bottom of a water body
  • Benthic mats control invasive mussels by restricting water flow through the mats, withholding oxygen and food from the mussels beneath the mats, and blocking light to prevent photosynthesis from producing oxygen beneath the mats. In some cases they prevent larval mussels (veligers) from spreading
  • Benthic mats were used by the Texas Parks and Wildlife Department to treat zebra mussels in Lake Waco, TX beginning in 2014
  • Water drawdowns occur when managers decrease the maximum depth in a body of water.
  • Drawdowns work to fight invasive mussels by exposing more shoreline and decreasing the capacity of the remaining water to retain heat. The exposure of mussels to freezing temperatures inhibits their ability to function and may kill them, depending on the length of the drawdown
  • Winter water drawdowns were used to treat Lake Zumbro, MN and Edinboro Lake, PA in 2000 and 2001. A complete drawdown of Lake Zorinsky, NE, in 2010 resulted in the eradication of zebra mussels within the lake, and the lake was refilled and re-opened for recreation in 2012
  • Invasive mussels can be manually removed from water bodies in a number of ways, including scraping and suction removal
  • Manual removal can be highly resource-intensive, but is efficient in ensuring removal of both live mussels and dead shells – removing shells helps to return the water body to its natural state
  • Manual removal was used in Lake George, NY, in 2000, and is currently in use at Good Harbor Reef in Sleeping Bear Dunes in Lake Michigan

Other Treatments

  • Species that eat zebra and quagga mussels can be introduced to a water body with invasive mussel populations
  • Once present, a biological control species will eat invasive mussels, removing them from specific locations
  • Redear sunfish have been studied in the Western United States as a potential control method for quagga mussels, where the species is native and naturally occurring
  • Carbon dioxide is a naturally occurring gas that is a byproduct of respiration
  • The addition of carbon dioxide to the water column removes oxygen from the water, suffocating any mussels in the area
  • The U.S. Geological Survey is currently investigating the efficiency of carbon dioxide as a control method for invasive mussels

Resources & Publications

Zequanox Application Technique Pilot Study on Lake Erie

Megan M. Weber, Marrone Bio Innovations; Michigan Department of Environmental Quality

Zebra Mussels Invade Ontario Waters

Ontario's Invading Species Awareness Program