News release: Zebra mussels confirmed in Fish Lake in Hennepin County

October 18, 2022

The Minnesota Department of Natural Resources has confirmed a report of zebra mussels in Fish Lake, near Maple Grove in Hennepin County.

Three Rivers Park District staff contacted the DNR upon finding one adult zebra mussel on a settlement sampler near the south public access to Fish Lake. Settlement samplers are solid surfaces placed in the water, which people can regularly check for attached zebra mussels, to aid in detection.

The DNR and Three Rivers Park District staff conducted a diving and wading search of four areas of the lake and found juvenile and adult zebra mussels at each location. More than 30 zebra mussels were found during the three-hour search.

Whether or not a lake has any invasive species, Minnesota law requires people to:

  • Clean watercraft, trailers and equipment to remove aquatic plants and prohibited invasive species.
  • Drain all water and leave drain plugs out during transport.
  • Dispose of unwanted bait in the trash.
  • Never release bait, plants or aquarium pets into Minnesota waters.
  • Dry docks, lifts and rafts for 21 days before moving them from one waterbody to another.

These additional steps reduce the risk of spreading aquatic invasive species:

  • Decontaminate watercraft and equipment – find free stations on the courtesy decontamination page of the DNR website.
  • Spray with high-pressure water or rinse with very hot water (120 degrees for at least two minutes or 140 degrees for at least 10 seconds).
  • Dry watercraft and equipment for at least five days before using in another waterbody.

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 on the aquatic invasive species page of the DNR website.