Zebra mussels confirmed in East Spirit Lake, Lake Osakis

The Department of Natural Resources has confirmed zebra mussels in northwestern Minnesota’s East Spirit Lake in Otter Tail County and central Minnesota’s Lake Osakis in Todd and Douglas counties. 

On July 9, an East Spirit Lake user brought a one-quarter inch zebra mussel to the DNR Fergus Falls office. A subsequent two-day search of four locations by DNR staff found one live zebra mussel one-quarter mile from the initial report.

On July 20, DNR invasive species staff conducted dive and shoreline searches to investigate reported zebra mussel veligers (larvae) in Lake Osakis. They found two three-quarter inch adult zebra mussels.

Invasive species alert signs are being posted at lake accesses, and the DNR will determine whether connected waters will also be added to the infested waters list. The DNR appreciates the help of the alert citizen who reported the find on East Spirit Lake and the work of the Sauk River Watershed District collecting veligers that led to the confirmation in Lake Osakis.

While zebra mussels are a serious problem for infested lakes, more than 98 percent of Minnesota’s lakes are not listed as infested with zebra mussels. To protect the state’s waters from the spread of invasive species and the environmental, recreational and economic damage they cause, Minnesota law requires boaters and anglers to:

  • Clean their watercraft 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.

In 2016, there are more DNR-trained watercraft inspectors and more decontamination units on Minnesota lakes than ever before. Watercraft inspectors check to ensure that boaters and anglers follow clean, drain, dispose laws and may deny access if necessary. Decontamination stations provide a free and thorough process of removing aquatic plants and animals.

More information, including a 30-second public service announcement about stopping the spread of aquatic invasive species, is available on the web page.