Zebra mussels found on Pike Lake near Duluth

A local resident found four zebra mussels while snorkeling in Pike Lake near Duluth last week, and both Minnesota Department of Natural Resources (DNR) and Minnesota Sea Grant biologists have now confirmed the discovery. Doug Jensen with Minnesota Sea Grant said the varied sizes of the mussels indicate they have been present in the lake for at least two years.

The zebra mussel is a nonnative invasive species that poses serious ecological and economic threats to Minnesota’s lakes and streams. Heavy infestations can kill native mussels, harm fisheries, litter beaches with sharp shells, clog water intakes, and damage boat motors. Native to Eastern Europe and Western Russia, zebra mussels were first discovered in Minnesota in 1989 in the Duluth-Superior Harbor. They subsequently spread to inland lakes including Mille Lacs, Prior, Le Homme Dieu, and to portions of the Mississippi, St. Croix, and Zumbro rivers.

The discovery of zebra mussels in Pike Lake is not surprising due to the location near Lake Superior where they have been present for 20 years. The infestation is disappointing because the DNR and the local Pike Lake Association have co-sponsored DNR watercraft inspectors at the public water access for several years.

“Zebra mussels in Pike Lake and Lake Superior pose risks for other waters in northeast Minnesota,” said Jay Rendall, DNR’s invasive species prevention coordinator. “Boaters and anglers will need to be extra careful to avoid spreading zebra mussels to nearby waters.”

To help stop aquatic hitchhikers like zebra mussels, boaters can take a few simple precautions:

• Inspect and remove all visible aquatic plants, animals and mud from boats, trailers and equipment, such as anchors, before leaving a water access.
• Inspect and remove all visible aquatic plants, animals or mud from docks, boat lifts and swim rafts before transporting to another water.
• Drain all water from boats - including live wells, bilges and bait buckets - before leaving a water access.
• Spray or rinse boats with high pressure and/or hot water, or let them dry thoroughly for five days before transporting to another water.

DNR will designate the lake an infested water and post signs to notify those using the public water access. Designation will make transport of water and harvest of bait from the lake prohibited. DNR increases inspections, enforcement and education around infested waters.

Under Minnesota law, it is illegal to transport aquatic plants, zebra mussels and other prohibited species. Violators could face fines up to $500.