The Wyoming Game and Fish Department recently confirmed the discovery of New Zealand mudsnails in the North Platte River near Casper and the Salt River south of Alpine in the Star Valley, according to a news release.

New Zealand mudsnails are a non-native aquatic invasive species that have spread throughout the Greater Yellowstone Ecosystem and now persist in several water bodies in northwest Wyoming.

This is the first finding on the North Platte River.

New Zealand mudsnails pose some issues for fisheries because they can alter water chemistry through filter feeding and reproduce at rapid rates. They crowd out habitat suited for stoneflies, caddisflies and other insects that are important food for trout.

The mudsnail can shield itself from toxins in the water, making chemical eradication of the species impossible.

Eric Hansen is a specialist in aquatic invasive species based at the Wyoming Game and Fish office in Casper.

The new infestations probably resulted from people not taking the time to clean, drain and dry their boats after being in one body of water before going to another body of water, Hansen said. "New Zealand mudsnails are easily transported on waders and drift boats."

The aquatic invasive species program focuses on intercepting invasive species like zebra and quagga mussels from out of state, but the expansion of the habitat of New Zealand mudsnails and curly pondweed represents a new threat, he said.

"Realizing that a simple task like cleaning your equipment, draining all standing water no matter how minimal and drying everything after each use will help exponentially in slowing the progress of these unwanted, water spoiling invaders," Hansen said.

Game and Fish will continue to monitor the population and conduct further sampling to determine the breadth of the infestation.