Lake Minnetonka Zebra Mussels

Sampling for zebra mussels in Lake Minnetonka, July, 2010.

Zebra mussels from Lake Minnetonka, July, 2010.

The purpose of this web page is to serve as a clearing house for information related to zebra mussels in Lake Minnetonka. This includes the latest information on:

• the distribution of zebra mussels in the lake
• potential impacts
• what homeowners and lake users can do
• information for lake service professionals and marinas
• upcoming meetings
• contact information of partners

Distribution of Zebra Mussels in Lake Minnetonka

Updated: September 7, 2010. Zebra mussels were discovered by a local resident on July 27, 2010 and confirmed by DNR biologists on July 28, 2010. After an initial survey was completed in early August, several agencies (DNR, Minnehaha Creek Watershed District field staff, Three Rivers Park District Staff and Lake association staff) are conducting a follow up survey to continue to determine the extent of the zebra mussel population in the lake. Earlier surveys found the zebra mussels to widespread in the eastern half of the lake in Grays Bay, Wayzata Bay, Browns Bay, Robinson's Bay, St. Louis Bay, the Lower Lake North portion of Lake Minnetonka, including the portions of Big Island. For the first time, a zebra mussel was found in Carmans bay, west of the narrows in the upper lake (see map below).

The widespread distribution of young zebra mussels indicates that there is a breeding population (size unknown) that has been in the lake for at least one year. Zebra mussels have also been detected in Minnehaha creek just below dam at the outlet of Lake Minnetonka. More surveys are planned in September.

Survey locations and documented occurrences of zebra mussels in Lake Minnetonka as of September 2010.

Zebra Mussel FAQs

• Zebra Mussels in Lake Minnetonka
  (Minnehaha Creek Watershed District)
• Zebra Mussels FAQs
  (Minnesota Department of Natural Resources and Minnehaha Creek Watershed District)
• Zebra Mussel Information
  (Minnesota Department of Natural Resources)

What You Can Do

There are a number of precautions lake users can take to prevent the spread of zebra mussels from Lake Minnetonka to other lakes, and to limit the harmful effects of this invasive species on your enjoyment of the lake.

Boaters, Anglers, and Swimmers:

• When swimming or wading, wear protective footwear to protect your feet from being cut by razor-sharp zebra mussel shells.
• Drain all water from your boat after each use to protect the cooling system of your boat.
• When you take your boat out of Lake Minnetonka, thoroughly clean your boat and trailer. Scrape off any encrusted mussels and spray your boat and trailer with high pressure and hot water.
• Before launching in another lake let it dry for at least five days. This will reduce the risk of spreading zebra mussels and other invasive Species.
• Livewells and portable bait containers must be drained before leaving the lake because the water could contain larvae of zebra mussels.
• It's the Law! Before you leave Lake Minnetonka you must ...
• Stop Aquatic Hitchhikers!

• Authorization Form for Watercraft Owners to Transport Watercraft with Prohibited Invasive Species From Designated Infested Waters for Cleaning / Storage

Homeowners or owners of boats permanently moored in Lake Minnetonka:

• Remove irrigation intakes from the water when not in use.
• If possible, keep your boat and motor out of the water when not in use minimize encrustation by zebra mussels.
• If it is not possible to store your boat out of the water, contact a marina to inquire about protective paints and annual maintenance.
• Run your boat long enough to reach operating temperatures. The immature zebra mussels are very sensitive to heat, so a hot engine will kill them as they are flushed through the cooling system.
• If you sell used docks, boat lifts, water toys, or other structures, be sure they are decontaminated and cleaned before they leave the area.
• Join the DNR's citizen zebra mussel monitoring program.

• Aquatic Invasive Species (AIS) Inspection and Cleaning Recommendations for Lake Minnetonka Residential/Community Use

Homeowners who want to dispose of aquatic plants:

Lake Service Providers and Marinas:

Partners