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Aquatic Invasive Species

Inspect. Clean. Dry.

Inspect, clean and dry your boat and gear between uses to stop the spread of aquatic invasive species such as zebra mussels, invasive weeds, and disease-causing organisms.

Photo of a bucket of water, splashing.

Keep your boat and gear clean and free of debris.






Aquatic Invasive Species (AIS) are organisms that are unintentionally brought into Montana from other places. These include clams, fish, mussels, plants, weeds, and disease-causing pathogens.

AIS are not wanted here. They overwhelm lakes and rivers, kill fish and plants, and damage the delicate ecosystem, that keeps our waters clean and abundant. AIS harms our recreational and agricultural resources by damaging boats and gear, clogging water pipes and hydropower facilities, jamming community water sources and choking off irrigation systems.

AIS can be spread when anglers, boats and other watercraft move from one body of water to another.

Report a Suspect AIS

If you see a boat or trailer with aquatic organisms attached to it, call TIP-MONT (406) 847-6668 immediately.

If you see or suspect a new infestation of an invasive plant or animal, please save a specimen and complete the following form:

You can also notify the FWP Fisheries office at (406) 444-2449.

How to Prevent Spread

Montanans and visitors need to be aware that aquatic diseases and invasive species can easily spread from one water body to the other.

Anglers, boaters and their equipment can transport these pests. It takes only one mistake to infest a new area. To protect Montana's waters and native aquatic species, please follow these guidelines:


After leaving a lake or stream, inspect your boat, engine, trailer, anchor, waders , and other fishing and boating gear for mud, water, and vegetation that could carry aquatic invasive species.


Completely remove all mud, water, and vegetation you find. Boaters should use a pressurized power sprayer, found at most do-it-yourself car washes. The hot water helps kill organisms and the pressure removes mud and vegetation. No need to use soap or chemicals.

3. DRY

Aquatic invaders can survive only in water and wet areas. By drying your boating and fishing equipment thoroughly, you will kill most invasive species. The longer you can keep your boat, trailer, waders, wading boots, and other equipment outside in the hot sun between fishing trips, the better.

Remember it is unlawful to move live fish, aquatic invertebrates or plants from one body of water to another without FWP authorization. It is also unlawful to release any live aquarium or bait fish.


This illustration shows the key areas to Inspect.Clean.Dry on any watercraft. Please Note: If you have traveled to a known infested area recently, ensure the watercraft and equipment is completely drained and dried. If you have concerns contact Montana Fish, Wildlife & Parks (406) 444-2449.

Contact Us

For more information, contact FWP at (406) 444-2449.