Aquatic Invasive Species
Flathead Lake in Montana faces a serious threat from invasive species, including zebra mussels, quagga mussels, and other aquatic invasive species (AIS). A mussel infestation in Flathead Lake would have devastating economic and environmental impacts, including reduced tourism, declining lakeshore property values, and damage to recreation like boating, fishing, and swimming. Sharp mussel shells would cover beaches, while decaying mussels could create foul odors along the shoreline. Invasive mussels also clog water infrastructure, increasing maintenance costs for drinking water systems, irrigation, and hydroelectric facilities, costs that would likely raise local water and electricity bills. These species disrupt the lake’s ecosystem by removing phytoplankton, leading to fish population declines, harmful algal blooms, and long-term water quality degradation in the Flathead watershed.
In addition to zebra and quagga mussels, other aquatic invasive species threaten Flathead Lake, including flowering rush, curlyleaf pondweed, Eurasian watermilfoil, and spiny water flea. These invasive plants and organisms outcompete native species, degrade fish and wildlife habitat, and interfere with recreation. Preventing invasive species in Flathead Lake is critical. Residents and visitors can help by cleaning, draining, and drying boats, stopping at watercraft inspection stations, participating in early detection efforts like shoreline mussel monitoring, and supporting funding for invasive species prevention in Montana. Protecting Flathead Lake from invasive species helps preserve clean water, recreation, and the local economy for future generations.
When transporting any type of watercraft, from a paddleboard to a wake boat or even when bringing in used recreation equipment like docks or boat lifts, stopping at inspection stations is mandatory and if you’re not a Montana resident you must purchase an Aquatic Invasive Species Prevention Pass before you launch on any body of water in the state.
Do your part to prevent AIS from spreading in Montana.
CLEAN. DRAIN. DRY.
DON’T MOVE A MUSSEL
Invasive Mussels
Early detection of invasive mussels is paramount to preventing an infestation. Once mussels are established, it is impossible to get rid of them.
Invasive mussels could forever change our watershed and the communities that depend on it.
Other Aquatic Invaders
Flathead Lake and watershed are at risk for an accidental introduction of aquatic invasive species. Our region’s scenic beauty is a magnet for visitors from out of state.
There are many plants, animals, and pathogens that pose a risk to our watershed.
What You Can Do
Zebra mussels are one of the most damaging aquatic organisms to invade the US. Help prevent their introduction.
Keep aquatic hitchhikers, like the zebra mussel, out of Flathead waters by cleaning your boat and gear.
Be a Montana Superhero! Spread the message, not the mussel!
Please share our short, fun video on why it is so important to Clean, Drain, and Dry all boats and equipment, and invite folks to share the video with others.