Inspectors find more boats transporting invasive species into Montana

Montana watercraft inspection stations have intercepted 13 boats carrying invasive mollusks into the state this year. As of May 30, inspectors have caught 12 boats with invasive zebra or quagga mussels and one boat with red rim melania snails attached to watercraft.

The mussel-fouled boats typically come from mid-west states or Arizona after having spent several weeks or months in mussel-infested waters. All boat owners must have their watercraft inspected when entering Montana.

Last week, a pontoon boat that was purchased in Minnesota came through the Flowing Wells watercraft inspection station located east of Jordan. The new owner planned to launch from Rock Creek in Fort Peck Reservoir and knew that the boat needed to be inspected before launch. Flowing Wells inspectors removed invasive mussels on weeds that were wrapped around the fuel line going to the engines of the boat. No other mussels were found on the boat.

Invasive Red Rim Melania snails were found on a motorboat at the Anaconda station on May 11. The boat was traveling from Lake Havasu, AZ, to Washington state when the Anaconda inspectors found the snails under a live-well screen. Red Rim Melania snails are native to Africa and Asia and are thought to have been introduced to North America when someone dumped an aquarium tank into open water.

Montana inspection stations have checked nearly 16,000 boats this year, which is 6,700 more boats than this time last year. Inspection numbers for March through May are greater than the previous two years.

FWP reminds all those transporting motorized or nonmotorized boats into Montana to have their watercraft inspected before launching. Boat owners are required to stop at all open watercraft inspection stations they encounter. To find a watercraft inspection station, go to or call the FWP Aquatic Invasive Species Bureau at 406-444-2440.

Aquatic invasive species (AIS) are non-native plants, animals or pathogens that can invade new waterbodies by hitching a ride on watercraft and gear. AIS can include mussels, snails, fish, plant fragments or larva that can only be viewed under a microscope.

Both motorized and non-motorized boat owners can help stop the spread of AIS by following the principles of clean, drain, dry.

  • Clean all mud and debris from the watercraft, trailer, waders and fishing equipment.
  • Pull drain plugs and make sure all compartments, bilges and ballasts are drained.
  • Dry out watercraft, including live-wells, storage areas and hatches.

Additional factors boat owners should be aware of:

  • Used watercraft purchased from out of state can pose a greater danger of harboring AIS.
  • Commercially hauled watercraft pose a higher risk as larger watercraft are often moored for extended periods of time.
  • Boats with ballast tanks or bladders can suck plants or animals into tanks and intake grates.
  • Fishing boats with live-wells or bait wells must be drained to prevent moving surface water where microscopic AIS could be found.
  • Nonresidents bringing boats to Montana must have their boats inspected before launching. They must also purchase a Vessel AIS Prevention Pass online here.