Deep-water divers, genetic testing and laboratory analysis of water samples did not detect any evidence of the presence of exotic mussels in Flathead Lake.

Montana Fish, Wildlife and Parks reported last November that water samples collected from the Woods Bay area indicated the possible presence of zebra or quagga mussel larvae.

The two rapidly reproducing species have wreaked havoc on ecosystems, boats and water systems in other parts of the country, and Montana has a program aimed at preventing the mussels from entering state waters.

The water samples with larvae were forwarded to laboratories for examination, including DNA testing, and three divers with the U.S. Geological Survey searched likely locations for mussels at the north end of Flathead Lake in December.

None of those efforts detected the presence of mussels in the lake.

Most recently, a scientist at the University of Montana’s Biological Station at Yellow Bay examined the larvae organisms and determined them to be “dinoflagegelate,” a tiny plankton common to Flathead Lake.

“We consider the results from each of these professional investigations to be terrific news,” said Eileen Ryce, aquatic invasive species coordinator for Montana Fish, Wildlife and Parks. “Still, we can’t let our guard down. We’ll continue to work with our partners at the Yellow Bay Lab and others to ensure we do everything we can to keep zebra and quagga mussels from becoming established in Flathead Lake.”