No Invasive Mussels Detected In Latest Flathead Lake Sample

Jul 27, 2017

The latest sampling results testing Flathead Lake for invasive quagga and zebra mussels are in, "and I'm happy to tell you that we have no detections," says Jim Elser, director of the University of Montana’s Flathead Lake Biological Station. Elser announced his lab’s latest data from samples taken in April.

The Bio Station uses an early detection technique called environmental-DNA that can identify trace amounts of any organism present — alive or dead — in a waterbody. That means the Station can run samples any time of year to detect the mollusk invaders that can cause millions of dollars of damage to hydropower dams and irrigation systems.

Montana Fish, Wildlife and Parks uses a technique called microscopy, which only works when microscopic mussel larvae are present in the water when the sample is taken.

The Bio Station sampled 30 sites on Flathead Lake for a total of 200 samples in April and last December, none of which indicated the presence of mussels. It will run samples again this fall and winter.

The station has also sampled 32 lakes across the state for quagga and zebra mussels and the highly invasive aquatic plant Eurasian watermilfoil.

Montana Fish, Wildlife and Parks says it’s intercepted 9 boats carrying invasive mussels this summer. The most recent was found at the Browning inspection station on July 16.

FWP has inspected more than 23,000 watercraft as part of its effort to keep the mussels, which can cause millions of dollars of damage to hydropower dams and irrigation systems, out of Montana’s waterways.

By the beginning of July, FWP wardens had issued 40 citations to people who bypassed the check stations, which is against state law and can come with a $500 fine.

FWP is continuing to monitor some lakes across the state for the presence of aquatic invasive species. So far, no positive detections have been found.