DNR officials say Bowstring Lake in northern Itasca County is the latest Minnesota lake discovered to be invaded by faucet snails.
The snails carry a wormlike parasite that can kill waterfowl, especially Scaup and Coots, said Christine Herwig, DNR invasive species specialist.
"There's concern that they're competing with other snails, which are food resources for waterfowl and fish," Herwig said.
Faucet snails are blamed for an extensive die-off of Scaup in one of north central Minnesota's larger lakes in 2007. They were first discovered in Minnesota in 2002 in the Mississippi River in the southern part of the state.
"They also can clog water intakes and out-compete native snails that provide a food resource for fish and other waterfowl and other species," Herwig said.
The faucet snail is a native of Europe and came here through the Great Lakes. People can eat fish from lakes infested with faucet snails. However they should avoid ducks or other birds that appear sick.
The DNR wants boaters to thoroughly clean their boats before departing lakes and rivers.