The Problem

Waters of northeastern North America are feeling the effects of invasive aquatic plants and animals transplanted from around the world. These organisms, introduced both intentionally and accidentally, can irrevocably alter our native ecosystems. Once “invaders” establish in a new ecosystem absent the control of their native predators, they can harm native species by preying on them, eating their food, transmitting diseases, outcompeting with them for habitat, or by simply outgrowing them. Entire ecosystems may be disrupted by habitat destruction or altered food chains. Not all non-native plants and animals cause serious problems, but those that do are known as invasive aquatic nuisance species or ANS.

The Effect

  • Each year in North America, federal, state, and provincial governments, utilities, and businesses spend billions of dollars attempting to prevent, control or slow the spread of ANS.

  • $500,000 is spent annually to manage and prevent the lakewide spread of water chestnut in Lake Champlain on the Vermont / New York border. Water chestnut has also been found in Massachusetts and Connecticut.

  • A 1999 Cornell University study estimates a $44 million per year economic loss to New England and the Canadian Maritime Provinces due to predation on commercially valuable shellfish by the introduced European green crab.

  • An economic study in New Hampshire showed that the value of property adjacent to lakes choked with aquatic weeds like Eurasian water milfoil is reduced by 15% or more. Invasive aquatic weeds are found in lakes throughout the Northeast region.

  • The State of Florida spends millions of dollars annually on herbicides and mechanical harvesters in an effort to keep the invasive aquatic plant, hydrilla, under “maintenance control.” Hydrilla has been found in both Connecticut and Massachusetts, and is anticipated to be able to grow as far north as the U.S./ Canadian border.

  • A pilot voluntary inspection program conducted by the State of Maine found more than 1,200 boats transporting aquatic weeds around the state, which could easily lead to numerous new infestations. Hundreds of thousands of recreational boats move throughout the Northeast annually.

  • Zebra mussels in the Great Lakes region have cost nuclear power plants an average of $800,000 annually for control. Even smaller municipalities in affected areas spend about $20,000 per year on control efforts. In the Northeast, zebra mussels are currently found in New York, Vermont, Connecticut, and Quebec.

  • A South American strain of human cholera bacteria was found in ballast tanks in the port of Mobile, Alabama in 1991. Cholera strains were also found in shellfish samples, resulting in a

public health advisory against the consumption of raw shellfish.

What is being done about ANS in the Northeast?

who we are... what we do...

The Northeast Aquatic Nuisance Species (NEANS) Panel was established in 2001, the fourth regional panel to be established under the auspices of the federal Aquatic Nuisance Species Task Force (ANSTF), following the Great Lakes, Western Regional, and Gulf of Mexico panels. The mission of the panel is to “protect the marine and freshwater resources of the Northeast from invasive aquatic nuisance species through commitment and cohesive coordinated action.” Using regional cooperative approaches, like the panels, to address this trans-boundary problem is extremely important to foster and ensure interstate coordination of effort, and to make the most effective use of resources.

The NEANS Panel addresses issues and concerns relative to the freshwater and marine resources of the states of Maine, New Hampshire, Vermont, Massachusetts, Rhode Island, Connecticut, and New York, and the Canadian provinces of Quebec, New Brunswick, and Nova Scotia. The panel’s members represent state, federal, and provincial governments, academia, commercial and recreational fishing interests, recreational boaters, commercial shipping, power and water utilities, environmental organizations, aquaculture, nursery and aquarium trades, tribal concerns, lake associations, and the bait industry, among others.

The panel has three working committees: policy and legislation, science and technology, and communications, education, and outreach. In addition, the panel’s steering committee is headed by freshwater and marine co-chairs.

For more information on the NEANS Panel, please contact Michele Tremblay in the U.S. at 603-796-2615 or Lara Gibson in Canada at 902-429-2202, or send an email to:

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Produced by the Communications, Education, and Outreach Committee, NEANS Panel, 2002. TEXT CREDITS: Many thanks to the Western Regional Panel for permission to use text from their “Threats to the West” brochure. PHOTO CREDITS: (front) water chestnut, Ann Bove, VTDEC; zebra mussels, National Aquatic Nuisance Species Clearinghouse; Asian shore crab, Nancy Balcom, CT Sea Grant.


You can help prevent the spread of aquatic nuisance species by following these guidelines:

  • Report sightings to your state/provincial natural resources or environmental protection agency, Sea Grant, U.S. Fish and Wildlife Service, Environment Canada, or Fisheries and Oceans Canada.

  • Learn more about non-native species and their invasion pathways.

  • Plant native plants in your garden; join a community group that is removing non-native, invasive plants and restoring native habitat.