Seeley Swan Pathfinder -

Invasive Dreissenid mussels pose one of the biggest threats to Montana’s waterways. Native to the Black and Caspian seas, the introduction of zebra and quagga mussels has given rise to extensive detrimental environmental and economic impacts throughout the United States. These invasive mussels are now found in every major watershed in the contiguous United States, except one. The Columbia River drainage basin, which encompasses most of western Montana, is the last major watershed in the country that has not been invaded by zebra and quagga mussels.

Watercraft inspection stations play a si...