Restrictions approved in effort to contain invasive mussel spread

HELENA, Mont. – The Montana Mussel Response team today announced immediate temporary emergency restrictions on the launch or removal of all boats, docks, and other structures for Tiber and Canyon Ferry reservoirs.

Matt Wolcott, Incident Commander for the State’s Mussel Incident Response Team, said the restrictions are necessary to prevent the potential spread of invasive aquatic mussels from the two reservoirs to other uncontaminated water bodies in Montana and elsewhere.

The restrictions were approved this afternoon by the directors of the Montana Department of Natural Resources and Conservation (DNRC) and Montana Department of Fish, Wildlife & Parks (FWP).

“This closure prohibits the launch or removal of any boat, dock, or other structure that could potentially transport mussels,” said Wolcott. “The closure will remain in effect until ice-up on the reservoirs.”

Wolcott said the Response Team, which includes officials from DNRC and FWP, will reassess whether to extend the closure following ice breakup in spring.

The larvae of aquatic invasive mussels were confirmed last month in water samples from Tiber Reservoir. Ongoing sampling and testing found “suspect” samples from Canyon Ferry Reservoir, the Milk River downstream of Nelson Reservoir, and the Missouri River upstream from Townsend. Wolcott said additional samples from those water bodies are being expedited and analyzed to provide definitive results. Water samples from more than 200 water bodies in Montana are currently being analyzed.

Governor Steve Bullock on Monday signed an executive order declaring a statewide natural resource emergency for all Montana waters due to the discovery of invasive mussels. The DNRC, FWP, and Montana Invasive Species Advisory Council have formed a rapid response effort, including a unified Mussel Incident Response Team and a Joint Information Center.