BEMIDJI, Minn. — A year after trace amounts of starry stonewort were discovered in Lake Beltrami, the Department of Natural Resources has confirmed an infestation of the aquatic invasive species in the lake.

According to a DNR press release, the invasive algae was discovered by DNR divers in the lake about 10 miles north of Bemidji. Last year, a volunteer found a strand of the algae near the lake's public access during a University of Minnesota Extension search event.

Subsequent searches and monitoring of the lake didn't reveal any other traces of the algae until this past weekend. The release states divers are now conducting hand-pulling of the algae, and will continue the process the rest of the summer to help manage the biomass.

The algae, originating from areas spanning Europe to China, was first confirmed in Minnesota in 2015 and has now been found in 15 of Minnesota's 11,842 lakes. The species can look similar to other native plants and can form dense mats, which can interfere with the use of a lake and compete with native vegetation.

Boat inspectors have also been expanded and follow-up surveys will take place to watch for the algae across the lake, according to the release.

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In the weeks ahead, Beltrami County Aquatic Invasive Species Technician Bruce Anspach said his team will meet with DNR officials to discuss the next move.

"We'll sit down and decide on a plan with the DNR," Anspach said. "We're at the point now where we know how much is there, and it seems to be the smallest amount in the county so far. We haven't decided on a treatment option, though."

Regionally, starry stonewort has been found in Cass Lake, Moose Lake, Wolf Lake, Upper Red Lake and Big Turtle Lake. At Big Turtle Lake, Anspach said chemicals have been used to try to combat the species.

"The chemical treatments for starry stonewort can knock it down, and it helps avoid contact with watercraft, but it doesn't get rid of it," Anspach said.

The DNR reminds boaters and anglers to follow Minnesota laws to prevent the spread of aquatic invasive species:

  • Clean aquatic plants and animals from watercraft.

  • Drain all water by removing drain plugs and keep drain plugs out while transporting watercraft.

  • 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, especially after leaving infested waters:

  • 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.

Details about starry stonewort and other aquatic invasive species are available at mndnr.gov/ais.