Swimmer’s Itch

Report swimmer’s itch cases here

Locations and severity of reported swimmer’s itch cases will be updated during the season.

2020 cases will be presented in map and spreadsheet form for both North and South Lake Leelanau, and updated every 1-2 weeks.

Donate here to help fund our efforts to control swimmers’ itch

Swimmer’s Itch FAQs

Latest research findings, future research direction, “smart swimming” techniques

Click here to read our Lake Biologist’s summary of the latest swimmer’s itch research findings, direction of future research and “smart swimming” techniques.

How does swimmer’s itch occur?

For more information on the life cycle of swimmer’s itch, click here. For examples of what swimmer’s itch looks like, click here or here.

How can I avoid swimmer’s itch?

SI is an allergic skin reaction to the parasites shown in the life cycle diagram and pictures. About 1/3 of the population is susceptible. If you’re a cottage owner, don’t feed waterfowl. Avoid swimming when the wind is blowing towards the shore, in the near-shore shallow areas, and in the morning. Some folks claim sunscreens protect you. “Swimmers Itch Guard” claims to be an effective repellent, and is available at several local pharmacies or online. A note of caution on “Swimmers Itch Guard”; it contains 20% eucalyptus oil and smells similar to “Vicks VapoRub”. LLLA communicates this information as a courtesy. LLLA has found no scientific studies that conclusively show any product as an effective repellent of SI. One of our members continues to work to develop an aesthetically acceptable and effective product.

What can I do if I get swimmers’ itch?

Itching may start from the time you are in the water up to a day later, and will last for about a week, accompanied by a rash. If itching and rash are severe contact a doctor for treatment. Temporary relief may be achieved through taking over-the-counter antihistamines, using anti –itch creams/lotions, or soaking in oatmeal or Epsom salts baths.

For a PDF info sheet on swimmer’s itch, follow this link.

MSU Extension Bulletin WQ-58. Also, follow this link to learn more about creams and lotions to prevent swimmer’s itch.

Mergansers are known to be carriers of swimmer’s itch – how can I identify them?

Use the following Youtube videos to verify your merganser identification. Several other species are included which are sometimes mistaken for mergansers.

Common merganser

Red breasted merganser



Canada geese

Common Goldeneye

Wood duck

Barrows Goldeneye


Swimmer’s Itch Reports and Links

Click on the links below for details of reported swimmers’ itch cases by
location and severity.  2020 cases will be presented in map and spreadsheet form for both North and South Lake Leelanau, and updated every 1-2 weeks.

2019 Report
2018 Annual Meeting Report
2018 North Lake Map
2018 South Lake Map
2017 North Lake Map
2017 South Lake Map
2017 Summary Report
2016 North Lake Map
2016 South Lake Map
2015 North Lake Map
2015 South Lake Map
2014 North Lake Map
2014 South Lake Map
2013 North Lake Map
2013 South Lake Map
2012 North Lake Map
2012 South Lake Map

SICON 2016 Final Report for “Bridge Program”.

SICON 2016 North Lake Leelanau snail sampling locations along with sampling data.

LLLA Swimmer’s Itch Benchmark Presentation to newly formed Michigan Swimmers Itch Partnership.

2 Replies to “Swimmer’s Itch

  1. Our dock and floating mat are swarming with a family of 9 brown ducks! The mess is horrific. I believe it is a merganser family that moves north along the shore from 2735 North Lake Leelanau Dr.
    Any assistance you could give us in locating the nest would be helpful.
    What diameter would the tree hole be? We have several holes in trees, but they seem too small for ducks.

  2. It sounds as if you are describing a family of mallards. We have surveyed North Lake as recently as yesterday, and found and removed only one merganser brood. Please send Wayne Swallow (leelanaubound@gmail.com) your email address and he will send you pictures of mallards and mergansers.

Leave a Reply