The South Dakota Game, Fish and Parks Department has confirmed the presence of zebra mussels in Big Stone Lake, a long, narrow lake that extends 26 miles through Big Stone County in Minnesota and two South Dakota counties. Zebra mussels were found on multiple docks being removed from the lake at the end of the season, on both the South Dakota and Minnesota sides of the lake.

Big Stone Lake abuts Big Stone Lake State Park in Minnesota and Hartford Beach State Park in South Dakota. Big Stone Lake is the source of the Minnesota River. Zebra mussels were confirmed in the Minnesota River in 2017.

“Zebra mussels are sometimes first discovered in lakes when lake property owners or lake service provider businesses remove boats, docks and equipment from the water at the end of the season,” DNR Invasive Species Unit Supervisor Kelly Pennington said.

Lake property owners should carefully look for invasive species on the posts, wheels and underwater support bars of docks and lifts, as well as any parts of boats, pontoons and rafts that may have been submerged in water for an extended period.

People should contact a Minnesota DNR aquatic invasive species specialist if they think they have found zebra mussels or any other invasive species that was not already known to be in the water body.

More information is available on the aquatic invasive species webpage of the DNR website.