Zebra Mussels

In July 2009, zebra mussels were discovered in Laurel Lake in Lee/Lenox, MA.  Laurel Lake is the first waterbody within the Commonwealth of Massachusetts where zebra mussels have been discovered.  Zebra mussels have also been reported in water bodies within the three states surrounding Berkshire County (New York, New Hampshire, and Connecticut).  Zebra mussels are a significant threat to Onota Lake and 7 or 8 other lakes in the Berkshires, all of which have the inherent chemistry favorable for Zebra Mussel growth.

Zebra mussels have the potential to inhabit most of the fresh waters of the U.S. and may impact a variety of native aquatic species and eventually entire ecosystems. These mussels are anchoring themselves by the thousands to native mussels making it impossible for the native mussel to function. As many as 10,000 zebra mussels have attached to a single native mussel. Native mussels have all but disappeared in Lake St. Clair and the western basin of Lake Erie where the Zebra Mussel infestation is believed to have originated. Female mussels can lay over one million eggs in a spawning season. They attach themselves to a hard surface and are difficult to remove. The larvae (called veligers) are microscopic in size and are undetectable by the human eye. They can be unknowingly transported in boat live wells and bait buckets or anything that carries small amounts of water (even on SCUBA equipment).

Zebra mussels were first discovered in the Great Lakes where their rapid spread caused substantial ecological and environmental impacts. The introduction of zebra and quagga mussels into the Great Lakes appears to be the result of ballast water discharge from ships.  Freshwater fishing and boating activities aid in the spread of zebra mussels allowing for overland transport or movement between water bodies.

The zebra mussel’s ability to rapidly colonize hard surfaces causes serious economic problems. These major biofouling organisms can clog water intake structures, such as pipes and screens, therefore reducing pumping capabilities for power and water treatment plants, costing industries, companies, and communities. Recreation-based industries and activities have also been impacted; docks, breakwalls, buoys, boats, and beaches have all been heavily colonized.

The introduction of zebra and quagga mussels into a waterbody dramatically and irreversibly changes the natural characteristics and use of the waterbody. Onota Lake, and the other Berkshire County lakes, has been extremely fortunate that the threat of zebra and quagga mussels has not yet impacted our waters. Without aggressive steps to prevent the infestation, it is only a matter of time before these harmful nuisances arrive. Prevention is the key as there is currently no known “silver bullet” approach to eliminating them once established.


Zebra Mussel Brochure
Mass.gov: “Zebra Mussels”
YouTube: “Zebra Mussels”


Fast Facts

Did you know that maximum lake speed is 45 mph?

For more information on Boater Safety see Boater Safety is Everyone’s Responsibility.

Did you know?

LOPA is an organization of volunteers. Our mission is to help the City of Pittsfield keep the lake clean and naturally beautiful for generations to come.

Why do a drawdown of the lake?

Lake drawdown is when the City of Pittsfield reduces the water level in the lake. Reasons: Shoreline erosion, weed management, flooding control.

How can I protect the Lake from Zebra Mussels?

Before launching a boat or kayak wash it thoroughly. Learn more about Zebra Mussels.

What You Can Do

Volunteer Opportunities

Beyond donations, there are many ways you can contribute to the preservation of Onota Lake. Here’s how you can help.


Become A Member

If you enjoy and appreciate Lake Onota, there’s a way you can give back. Becoming a LOPA Member means you support the preservation of this natural splendor.

Start Your Membership

What We Do

Our purpose is to assist the City of Pittsfield on all matters regarding Lake Onota. We’re a volunteer organization, providing education and scientific study to help preserve this beautiful place.

LOPA is the voice of Lake Onota, and our members are dedicated to its preservation and restoration.

Learn More About LOPA



Michael Riordan

Board Members

Lake Onota Preservation Association, Inc.
PO Box 2884
Pittsfield, MA 01202

City of Pittsfield

James McGrath
Park, Open Space, and Natural Resource Program Manager

Office of Community Development
City Hall
70 Allen Street
Pittsfield, MA 01201