Zebra mussels confirmed in Bde Maka Ska in Minneapolis

The Minnesota Department of Natural Resources has confirmed a report of zebra mussels in Bde Maka Ska, part of the Minneapolis Chain of Lakes. 

Zebra mussels were confirmed in Lake Harriet, immediately downstream of Bde Maka Ska, in September 2017.

A Minneapolis Park and Recreation Board watercraft inspector contacted the DNR after finding two juvenile zebra mussels on a sailboat as it was being removed from Bde Maka Ska for the season.

DNR invasive species staff conducted a dive search in the buoy field and at the access of the lake and did not find additional zebra mussels. Staff from the park board and Blue Water Science will conduct another search to help determine any further distribution of the zebra mussel population.

Because the sailboat had been moored in the lake for an extended period and the young zebra mussels indicate in-lake reproduction, treatment would likely not be effective. Early detection is still important, because it can help prevent spread to other lakes. The park board is inspecting all sailboats being removed from the lake. Zebra mussels have not been reported on any additional boats.

“To help prevent further infestations, we need people to do a thorough job of checking for zebra mussels and other invasive species when removing their boats, docks and lifts on all bodies of water at this time of year,” said Heidi Wolf, DNR invasive species unit supervisor.

Property owners, lake associations and lake service provider businesses should contact the DNR if they think they’ve found an invasive species.

Whether or not a lake is listed as infested, Minnesota law requires boaters and anglers to:

  • Clean watercraft and trailers of aquatic plants and prohibited invasive species.
  • Drain all water by removing drain plugs and keeping them out during transport.
  • Dispose of unwanted bait in the trash.

Some invasive species are small and difficult to see at the access. To remove or kill them, take one or more of the following precautions before moving to another waterbody:

  • Spray with high-pressure water.
  • Rinse with very hot water (120 degrees for at least two minutes or 140 degrees for at least 10 seconds).
  • Dry for at least five days.

Zebra mussels can compete with native species for food and habitat, cut the feet of swimmers, reduce the performance of boat motors, and cause expensive damage to water intake pipes.

People should contact an area DNR aquatic invasive species specialist if they think they have found zebra mussels or any other invasive species.

More information is available at mndnr.gov/ais.