Zebra Mussels: Missouri’s Most Unwanted

Life Jacket Programs 2012
16th May 2012
Lake of the Ozarks Zebra Mussel Update
15th October 2012
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Zebra Mussels: Missouri’s Most Unwanted

Zebra mussels and a related species, quagga mussels, are fingernail-sized black-and-white striped bivalve mollusks native to the Caspian Sea region of Asia. They came to North American waters in international shipping ballast water and were discovered in Lake St. Clair near Detroit in 1988. Since then, zebra mussels have spread rapidly.

Zebra mussels can clog power plants, industrial and public drinking water intakes, foul boat hulls, decimate populations of native freshwater mussels, impact fisheries and disrupt aquatic ecosystems. Economic impacts of zebra mussels in North America during the next decade are expected to be in the billions of dollars.

Overland transport on boats, motors, trailers and aquatic plants poses one of the greatest risk for spreading zebra mussels. Larger adult zebra mussels can live several days out of water in moist, shaded areas. Boats that have been moored or stored for more than just a day or two in zebra mussel-infested waters may carry “hitchhiking” mussels attached to their hulls, engine drive units and anchor chains. Boats that have been in infested waters for only a day or two are less likely to transport adult zebra mussels. Microscopic zebra mussel velgers can survive in boat bilge water, livewells, bait buckets and engine cooling water systems, regardless of how long the boat has been in infested waters.However, they will die very quickly when their hiding places are warmed in the sun or when they “blow dry” on the highway on the trip home.

How You Can Help Prevent Zebra Mussels Spread

If you are a water recreationist (boater, angler, water-skier, scuba-diver, sailor or canoeist) there are some important things you can do to prevent the transport of zebra mussels and other harmful exotic species from one lake or river to another.

  • When you get home – before launching your boat into uninfested waters – thoroughly rinse and dry the hull, drive unit, livewells (and livewell pumping system), bilge, trailer, bait buckets, engine cooling system and other boat parts that got wet while in infested waters; use a hard spray from a garden hose.
  • If your boat was in infested waters for a long period of time, or if you find any attached adult mussels, use HOT (104 F) water instead of cold, or tow the boat through a do-it-yourself carwash and use the high pressure hot water to “de-mussel” your boat. Do not use chlorine bleach or other environmentally unsound washing solutions.
  • Boats, motors and trailers should be allowed to dry thoroughly in the sun for at least five days before boating again.
  • In infested waters, the best way to keep a hull mussel-free is to run the boat frequently (small juvenile mussels are quite soft and are scoured off the hull at high speeds).
  • On boats which remain in the water, zebra mussels can attach to drive units, cover or enter water intakes, and clog, overheat and destroy the engine. If possible, leave outboards or outdrives in the up position. Periodically inspect hulls and drive units, and scrape free of mussels. Pump hot water through your engine’s intake on a regular basis to prevent mussel growth inside the engine’s cooling system.
  • Learn what these organisms look like (at least those you can see). If you suspect a new infestation of an exotic plant or animal, report it to your natural resource agency. Consult the agency for recommendations and permits before you try to control or eradicate an exotic “pest.” Remember, exotic “pest” species thrive on disturbance. Do-it-yourself control treatments often make matters worse and can harm native species.

To report a potential zebra mussel sighting or for additional information, contact your nearest Missouri Conservation Department Office orThe Invasive Species Coordinator at Missouri Department of Conservation, P.O. Box 180, Jefferson City, MO 65102-0180 or Phone: 573-522-4115 ext. 3371

Several Missouri Stream Teams already are helping by monitoring streams for zebra mussels. If you would like to join the effort, call (800) 781-1989 or visit the Stream Team web-site at MO Stream Team.

Source: Missouri Department of Conservation