Aquatic Invasive Species

Keeping the Clark Fork Invader-Free

The Clark Fork Coalition and other watershed groups are working alongside agencies to monitor the presence of aquatic invaders and to help stop their spread.

Protect our Waters: The Protect Our Waters webpage was created in response to the discovery of mussels in Montana in 2016, it as an important resource for current regulations, up-to-date maps of inspection and decontamination stations, and Certified Boater information.

Stop Aquatic Hitchhikers: The Stop Aquatic Hitchhikers! campaign empowers recreational users of aquatic resources in the United States and other countries to help stop the spread of harmful aquatic invasive species through outreach and partnerships. This website can help you understand the threats of aquatic invasive species, learn to recognize aquatic invasive species, and learn to Clean, Drain and Dry all watercraft, trailer, motors, and gear every time, everywhere.

Confederated Salish & Kootenai Tribes: The Confederated Salish & Kootenai Tribes are taking action to protect their waterways from invasive mussel and other aquatic invasives, and their website is an important place to visit before you plan to boat on any Flathead Reservation waterbody.

What are Aquatic Invasive Species? 

Aquatic invasive species (AIS) are non-native, nuisance plants, snails, or mussels that typically enter waterways via unintended human introduction. Unfortunately, several types of aquatic invasive species have taken root in the Clark Fork watershed. To-date, Eurasian milfoil, curlyleaf pondweed, saltceder, purple loosestrife, flowering rush and yellowflag iris are the most prevalent invaders in the basin, but with the discovery of mussel larvae at Tiber Reservoir and suspect detections at Canyon Ferry Reservoir, invasive mussels are now at the doorstep of the Clark Fork Watershed. Once invasive mussels are established they’re nearly impossible to eradicate, so preventing their spread is the best course of action to protect the Clark Fork Watershed.

Why are they a problem?

Aquatic invasive species can cause widespread ecological havoc and economic harm — for example, scientists estimate that over 180 invasive species in the Great Lakes cost more than $200 million annually in lost revenue and prevention strategies. Last fall invasive mussel larvae were discovered in samples from Tiber Reservoir and now we are working overtime to prevent their spread.

Threats include:

  • Crashing fish populations
  • Loss of native flora and fauna
  • Decline in water quality
  • Increase in the frequency of toxic algae blooms
  • Reductions in local tourism, recreation, and property values
  • Beaches covered with sharp shells
  • Increased costs for cleaning and maintaining water system pipes used in domestic, municipal, agricultural, and hydroelectric facilities.

Did you know? The Columbia River Basin is the last mussel free watershed in the lower 48! And the Clark Fork sits at the headwaters. Whatever enters our system eventually makes it downstream. We have a duty to protect our watershed and others from the devastating effects of these non-native invasive mussels.

What you can do:

Besides stopping at watercraft inspection stations, boat users, anglers, and recreationists need to go the extra mile to prevent the devastating impacts of invasive species on our blue ribbon trout streams and pristine high alpine lakes.

To help prevent the spread of weeds, mussels and snails take the critical step to clean, drain, and dry boats, boots and gear after spending time on rivers or lakes.

CLEAN. Completely remove all mud, water, and vegetation before leaving the access areas.

  • Inspect your boat, trailer, and all gear. Pay attention to crevices and hidden areas.
  • Remove all vegetation (by hand or sprayer).
  • Remove all mud (use a pressurized power sprayer, found at most do-it-yourself car washes).  The hot water kills organisms and the pressure removes mud and vegetation. No need to use chemicals or soap.
  • Dispose of debris in trash or on dry land away from water, docks or boat ramps.

DRAIN. Drain all water from watercraft and equipment.

  • Drain or remove water from boat, bilge, live well, engine, internal compartments, and bait buckets by removing drain plugs before leaving the access area.

DRY. Aquatic invaders can survive only in water and wet areas.

  • Dry your watercraft and fishing equipment thoroughly; this will kill most invasive species.  The longer you keep your watercraft, trailer, waders, and other equipment outside in the hot sun between fishing trips, the better.

Speak up to protect our waters! See a suspicious-looking aquatic plant? A non-native mussel? A boat coated in weeds? Call 1-800-TIP-MONT to report what you see on our lakes, rivers, and streams. 

It’s up to us to keep the Clark Fork Watershed invader free!