Groups Try to Keep Flathead Waters Free of Invasive Species

By Beacon Staff

POLSON – Two conservation groups have joined with local, state, federal and tribal governments to try to keep the lakes and rivers of the Flathead Basin free of invasive aquatic species.

The Flathead Basin Commission and the Flathead Lakers want to keep zebra and quagga mussels, as well as Eurasian water milfoil plants, out of the area.

The mussels, which multiply rapidly, can rob fish of the plankton they need to survive. The groups say the bivalves can easily move from one water system to another by catching a ride on a boat hull or trailer. Their larvae also can spread through a boat’s bilge system or on sediment stuck to a fisherman’s waders.

In Lake Michigan, mussels have crawled their way through mesh netting and clogged pipes as large as 3 feet in diameter. They can ruin boat motors by destroying their coolant system, and when they die, their razor-sharp shells wash up on shore and make beaches unusable.

“Folks really have to be diligent, especially if they’ve been in waters outside the basin,” said Caryn Miske, executive director of the Flathead Basin Commission.

Miske said the group is looking at establishing eight or nine checkpoints for people towing boats. If there was any evidence or suspicion that invasive species might be present, the boats and trailers would be washed and sent on their way.

The threat of the Eurasian water milfoil, which forms dense mats of vegetation on the surface of water, also is a threat. The growth can interfere with recreation and can clog power generation and irrigation water intakes. The mats also can become excellent habitat for mosquitoes.

The groups are trying to draft a plan with the Confederated Salish and Kootenai Tribes, the Flathead Conservation District, the Flathead Lake Biological Station, Glacier National Park, Lake County, the Montana Department of Agriculture, the U.S. Geological Survey and the Whitefish Lake Institute.