Non-native Species Latest: Invasive zebra mussels have reached Montana Their arrival could have drastic economic effects.

Tom Britt/CC Flickr

BACKSTORY

Invasive quagga and zebra mussels appeared in the 1980s from the Black Sea, spreading through the Great Lakes before jumping to Nevada’s Lake Mead in 2007. The tiny mussels multiply rapidly, clogging water intakes and disrupting food webs. With no native predators, they are extremely hard to vanquish. Their microscopic larvae hitch rides to new bodies of water on boats and waders (“Wish you weren’t here,” HCN, 3/5/07).

FOLLOWUP

The mussels have now reached Montana, after infesting Nevada, Utah, California, Colorado and Arizona. State labs analyze samples from hundreds of water bodies annually for the presence of the mussels, and on Nov. 8, they found larvae in Tiber and Canyon Ferry reservoirs. Glacier National Park and the Blackfeet Nation have banned any boating activity for now, though Montana’s cold winters may slow their spread. “This is going to be absolutely catastrophic to the economy and the environment,” said state Rep. Jim Keane, D-Butte, in the Flathead Beacon.