The U.S. Fish and Wildlife Service has closed the Jessup Mill Pond near Creston to all boating access while hatchery managers await updated sampling and information on the extent of invasive mussel contamination detected in Central Montana.

The spring-fed pond is used by the adjacent Creston National Fish Hatchery for rearing fish. Hatchery manager Mark Maskill said Wednesday that the agency has not encountered any evidence that mussel contamination detected in the Tiber and Canyon Ferry reservoirs earlier this month has reached the Flathead. He said the closure is a precautionary measure until additional water sampling and testing gives the pond a clean bill of health.

“What makes us different is our infrastructure. If quagga mussels were to get established, it would create havoc for the operation of the facility,” Maskill said. “If they were to be established in the hatchery, or in Jessup Mill Pond — our water supply — that would prevent us from stocking fish because we could potentially move those (mussel larvae) around.”

Water samples taken from the pond this summer are still awaiting testing by Montana Fish, Wildlife and Parks. Maskill expects the results within the next month or so.

He said the pond’s popularity among non-motorized boaters, kayakers and paddleboarders has roughly tripled in recent years. Despite the cold weather, it’s also a popular spot for duck hunters this time of year.

The soonest the mill could re-open to non-motorized watercraft is next spring, Maskill said.

The pond’s closure follows similar actions during the past week by Glacier National Park and the Blackfeet Nation after the state’s first positive detection of invasive mussels was announced last week.