Zebra mussels confirmed in 3 metro-area lakes

The Minnesota Department of Natural Resources has confirmed reports of zebra mussels in Bald Eagle Lake and Lake Johanna in Ramsey County and Lake Isabelle in Dakota County. 

As part of the lake association’s zebra mussel monitoring program, one juvenile zebra mussel was found on a settlement sampler on the south side of Bald Eagle Lake. Settlement samplers are solid surfaces placed in the water that people can regularly check for attached zebra mussels.

An early detection survey by a county consultant on Lake Johanna revealed one large adult zebra mussel near the public access.

During Saturday’s University of Minnesota Extension “Starry Trek” search day, a trained detector found three zebra mussels attached to the fishing pier on Lake Isabelle.

The DNR is conducting follow-up surveys of all three lakes to determine whether zebra mussels are distributed more broadly and assess whether there are treatment options. Early detection increases the potential for treatment and helps to prevent spread to other lakes.

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.