DEP Reports Zebra Mussels Discovered in Lake Zoar and Lake Lillinonah
First New Confirmation of this Invasive Species in Connecticut Since 1998
The Connecticut Department of Environmental Protection (DEP) today announced that the aquatic invasive species, Zebra mussel, has been discovered in Lake Zoar and Lake Lillinonah, two large impoundments on the Housatonic River in western Connecticut.
This is the first report of a new infestation since zebra mussels were first discovered in Connecticut in 1998 in East and West Twin Lakes in Salisbury. While only small numbers of the zebra mussels have been discovered so far – and it could take a relatively long period of time for them to have an impact – At this point it is uncertain if the mussels found in Lakes Lillinonah and Zoar are the result of downstream migration from upstream sources or the result of a separate introduction.
“This is a disturbing discovery,” said DEP Commissioner Amey Marrella. “Only small numbers of the zebra mussels have been discovered so far, and it could take some time before we see the impact they may have. The zebra mussels have the potential, however, to do much damage by displacing native mussels, clogging power plant and industrial water intakes, affecting public drinking water distribution systems and disrupting aquatic ecosystems.”
“Zebra mussels can be spread from one water body to another through boating and fishing activities and Connecticut’s boating and angling communities have worked closely with us the past 12 years to prevent this from happening,” Commissioner Marrella said. “With this latest news, it is now time to redouble our efforts to make certain everyone on our waters is aware of common sense precautions they can take to help contain the spread of zebra mussels.”
The zebra mussel is a black and white-striped bivalve mollusk, which was introduced into North American waters through the discharge of ship ballast water. Since its discovery in Lake St. Clair (Michigan/Ontario) in 1988, the zebra mussel has spread throughout the Great Lakes, the Mississippi River system and most of New York State. Zebra mussels were first found in the Housatonic River in 2009 when they were discovered in Laurel Lake in Lee, Massachusetts, and subsequent sampling found them in the lake’s outflow into the mainstem river.
Zebra mussels have fairly specific water chemistry requirements, and are limited to waters with moderate to high calcium concentrations and pH. In Connecticut, suitable habitat for zebra mussels is mostly limited to a number of water bodies in western portions of the state.
The mussel can foul boat hulls and engine cooling water systems and clog power plant, industrial and public drinking water intakes. Sites that may be affected on the Housatonic River include the hydroelectric facilities at Falls Village, Bulls Bridge, Lake Lillinonah, Lake Zoar, Lake Housatonic, and the pump-storage facility at Candlewood Lake.
“DEP is seeking the continued active cooperation of boaters and anglers to follow practices that help prevent the spread of zebra mussels and other aquatic invasive species,” said Commissioner Marrrella. “We also encourage the public to make DEP aware of any indications of zebra mussels or any other invasives they may have seen.”
The DEP Boating Division is posting signs at Lakes Lillinonah and Zoar alerting the public to the presence of the zebra mussels in those waters and listing steps they should take to prevent them from spreading. DEP is also posting signs at nearby Lakes Candlewood and Housatonic, as well as Squantz Pond, which are all interconnected and have water qualities making them susceptible to the zebra mussels. These signs will alert the public to the fact that this invasive species has been detected in nearby water bodies and that proper precautions should be taken.
Actions anglers and boaters can take to prevent the spread of zebra mussels include:
Before Leaving a Boat Launch:
- Completely drain all water from the boat, including bilge water, livewells and engine cooling systems.
- Inspect your boat, trailer, and equipment. Remove and discard all aquatic plants and animals you may have picked up while on the water.
- Rinse boat, trailer and equipment with tap water. A bleach solution can be used to clean livewells. Dispose of all rinse material properly!
- Do not dump your bait bucket or release live bait! Avoid introducing unwanted plants and animals. Unless your bait was obtained on site, dispose of it in a suitable trash container.
- Do not transport fish, other animals or plants between water bodies. Release caught fish, other animals and plants only into the waters from which they came from.
The DEP will continue to monitor for the presence of zebra mussels at these lakes and others throughout the state. Individuals wishing to report possible sightings of zebra mussels and other aquatic nuisance species can contact DEP’s Inland Fisheries Division at 860-424-3474. More information on zebra mussels and other aquatic nuisance species can be found on the DEP website (www.ct.gov/dep) in the:
- 2010 CT Angler’s Guide (www.ct.gov/dep/lib/dep/fishing/anglers_guide/anguide.pdf)
- 2010 CT Boater’s guide (www.ct.gov/dep/lib/dep/boating/boating_guide/boaterguide.pdf).