Citing the low level of risk for invasive mussels to be transported to other bodies of water in the state, Montana officials on Tuesday lifted boating restrictions on Tiber and Canyon Ferry reservoirs.

The restrictions were put into place in December, after preliminary testing of water samples from the two Central Montana reservoirs indicated the presence of invasive mussel larvae.

“Winter is a low-risk season for transmitting mussels from one water body to another since zebra and quagga mussels don’t reproduce when water temperatures drop below 48 degrees,” a Tuesday press release from the Montana Mussel Response Team stated. “The team is considering options for how to minimize the risk of spreading mussels from Canyon Ferry and Tiber to other waters, and will reassess whether to extend or implement other restrictions following ice breakup in spring.”

State biologists believed the larvae to be from either zebra or quagga mussels — two aquatic invasive species that have spread other parts of the country. In many lakes and rivers, the mussels have multiplied voraciously, coating underwater surfaces and damaging dam and irrigation infrastructure, boats, aquatic ecosystems and recreation-based economies.

In late December, the team announced that after completing its analysis of hundreds of additional water samples from throughout the state, the presence of invasive mussel larvae appeared confined to Tiber Reservoir. To date, invasive mussels have never been detected west of the Continental Divide in Montana, or elsewhere in the Columbia River Basin.

Immediately following the state’s announcement of its initial detections in November, Glacier National Park and the Blackfeet Nation closed all waters within their boundaries to all watercraft. Those restrictions still remain in place.

“It is still important for ice fisherman and other winter recreationists using these reservoirs to take precautions and clean, drain and dry their equipment properly,” the state mussel team’s press release added.

Reporter Sam Wilson can be reached at 758-4407 or by email at swilson@dailyinterlake.com.