Montana officials say two boats carrying invasive mussels were stopped at watercraft inspection stations over the Memorial Day weekend.
Fish, Wildlife and Parks officials say one crossed into eastern Montana from the Great Lakes Region on May 26 bound for West Yellowstone. Staffers hot-washed the boat, which was then taken to Bozeman for a complete decontamination.
The second boat passed by an inspection station at Hardin on May 27 and a trooper made the driver return to the station. The boat was washed and Canadian authorities were alerted because it was being hauled to British Columbia.
Montana requires watercraft coming into the state to be inspected after the discovery of aquatic invasive mussel larvae at Tiber Reservoir. Tests raised suspicion that larvae were also in Canyon Ferry Reservoir.
Aquatic mussels can spread quickly, clogging water pipes, displacing native species and causing other economic and environmental problems.
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