Zebra mussels confirmed in Big Watab Lake in Stearns County

August 20, 2020

The Minnesota Department of Natural Resources has confirmed zebra mussels in Big Watab Lake, near Avon in Stearns County.

The DNR was notified after children swimming in Big Watab Lake found a zebra mussel. DNR invasive species specialists found 24 zebra mussels along a one-tenth mile stretch of shoreline during a follow-up survey. The range of sizes and ages of the zebra mussels indicates a reproducing population in the lake. 

The DNR is coordinating with the lake association on further surveys and monitoring. While zebra mussels have not been eradicated from any lake after becoming established, early detection and heightened prevention efforts can help protect other bodies of water.

Whether or not any invasive species has been confirmed in a lake, 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 are an invasive species that 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 a Minnesota 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.