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Aquatic Invasive Species in New York State

View a list of awardees for the aquatic invasive species (AIS) spread prevention grant program.

Invasive aquatic plant species hanging off a trailered boat after it was pulled from the water.

What do Eurasian watermilfoil, Didymo, water chestnut, purple loosestrife, fishhook water fleas, zebra mussels, and round gobies have in common? They are all species from other parts of the world that have been accidentally introduced and have flourished in New York State, oftentimes at the expense of valuable native species. Add to this list sea lamprey, white perch, fanwort, yellow perch, and a host of common baitfish species that are native to the U.S., and in some cases NY, but have since spread to water which they were not originally found. These plants and animals are all considered invasive species and, when they become problems, are termed nuisance invasive species. Without the predators, parasites and diseases that control their numbers in their native habitats, these species can reproduce and spread at an amazing pace. Similarly, fish diseases such as whirling disease and viral hemorrhagic septicemia (VHS) have also been introduced to New York State. Although these diseases are not a threat to human health, they can have dire consequences for our native fish communities.

Some of these species were introduced into New York via ballast water discharges, as ships from ports around the world travel up the St. Lawrence Seaway and into the Great Lakes. Many exotic aquatic plants have been introduced through the home aquarium trade. The mechanisms by which other organisms are introduced, including many fish diseases, are still unclear. What is clear is that as anglers and boaters move from water to water these invasives can be unknowingly spread. This can occur by failing to properly dry or disinfect boating and fishing equipment, improperly using and disposing of baitfish, or illegally moving fish from water to water.

Protecting the Adirondacks

In March 2015, Governor Cuomo announced an agreement to prevent the spread of aquatic invasive species in the Adirondacks. 50 Conservation Groups, Owners Associations, Local and State Governments have signed on to the Memo of Understanding (PDF, 134 KB) to help preserve clean water, increase recreation opportunities and promote tourism in New York. See Governor Cuomo's press release (leaves DEC website) for more information.

How You Can Help

Anglers and boaters are asked to be aware of the part they may play in the spread of invasive species in New York State and take action to help stem their spread. Unfortunately, there is no single preventative action that can address all invasive plant and animal species, or diseases that an angler or boater may come in contact with. Following recommended guidelines will lessen the likelihood of spreading these species and diseases as you fish or boat.

Aquatic invasive species may also be spread to lakes, rivers, and ponds via aquarium release or escape. Aquarium species such as koi, goldfish, and red-eared slider turtles sometimes lack predators in the wild and are able to grow and reproduce rapidly. Invasive plants such as Brazilian elodea, fanwort, and hydrilla are often sold as oxygenators for aquariums. If they aren't disposed of properly, these plants can become established in the wild and cause dense infestations that compromise water quality for recreation and human consumption. See our Guidelines for Owners of Aquariums and Exotic Pets (PDF, 350 KB) to learn how to own and dispose of aquarium species responsibly.


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