Aquatic Nuisance Species

• Nuisance Species
• Prevent the Spread
• Look-Alike Aquatic Plants
• NH Infested Bodies of Water

Introducing harmful, non-native organisms into New Hampshire's waters can lead to environmental damage and declines in the aesthetic and recreational appeal of our lakes, ponds, and rivers. As of Spring 2003, the law prohibits the transport and introduction of exotic aquatic plants in New Hampshire!

Variable Milfoil is a non-native plant that has taken over many bodies of water in New Hampshire. It interferes with boating, fishing, swimming, and the ecology of the body of water. The plant is spread easily when boat propellers, fishing line, or other recreational gear cuts off pieces of the plant. These pieces then can travel to new parts of the body of water to root; or they can be trapped on boats and trailers, diving gear, and fishing equipment and moved to a new body of water. A single fragment of this plant can cause a new infestation. There are also other aquatic plants that can be as problematic, including hydrilla, Brazilian elodea, fanwort, Eurasian milfoil, and water chestnut.

Zebra Mussels are about the size of a human fingernail, or a pistachio nut, but cause hundreds of millions of dollars in damage across the U.S. They pose a serious threat to water supplies, industrial processing plants, marine engines, and recreation. Zebra mussels clog water intake pipes and can give bad odors to bodies of water. Their sharp shells also can cut the feet of swimmers.

Here's what you can do to prevent the spread of aquatic nuisance species:

• Inspect your boat and trailer, removing all aquatic organisms (zebra mussels and any aquatic plants).
• Drain your motor, live well, and bilge on land before leaving the body of water.
• Empty bait buckets on land before leaving a body of water.
• Never release live bait into a body of water or release aquatic animals from one body of water into another.
• Rinse your boat, propeller, trailer, live well, and equipment; and hand-remove anything trapped between the boat and trailer.
• Air dry your boat and equipment for as long as possible—five days is optimal.
• Flush the engine's cooling system with hot water.
• Apply antifouling materials such as paint and films to boat hulls, trim tabs, water ports, transducers, and swimming platforms to discourage zebra mussel attachment.
• Avoid boating through dense beds of aquatic plants.
• Report any new suspicious plant growths to the NH DES at 603-271-2248.

What is New Hampshire doing to combat exotic aquatic plants?

The Lake Host Program was developed to prevent new infestations of exotic aquatic plants in New Hampshire's lakes and ponds. Volunteers conduct quick and friendly inspections of your boat, trailer, and other recreational gear for exotic plants that may have become attached.

Weed Watchers is another program made up of volunteers who patrol lakes and ponds monthly to inspect the water for new or suspicious growths of plants. Weed Watchers strive to detect these new growths before the plants become a problem.

For more information about exotic species or to become a Weed Watcher, call the NH DES at 603-271-2248 or visit NH DES online.

Commonly Confused Look-Alike Aquatic Plants

Infested Bodies of Water in New Hampshire