Yes! Our lakes are special but did you know that when it comes to Swimmer’s Itch, Glen Lake is not unique? Nearly all “up north” lakes have some form of the itch; in fact this is the case on a global scale. A well-documented ecological zone of itch-causing worms exists at or near the 45th parallel and not just across North America, but Europe as well. So what can we do?
Management to reduce itch remains an important part of our strategy. GLA removed record numbers of broods this year. 171 mergansers from 17 broods were relocated, while on other nearby lakes, there were zero to two broods. Why are our numbers so much higher than other lakes in the region? It may be that the great August storm of 2015 created an abundance of nesting habitat, making our watershed irresistible to merganser ducks. And we’ve continued to receive unprecedented reports of new broods into August! Is it possible that hens that evade capture with their chicks are capable of producing a second brood in a season? These highly intelligent and adaptable waterfowl continue to provide scientific mysteries to solve.
Even with our best efforts to control the issue, it is clear that parasites causing Swimmer’s Itch will continue to persist in the natural environment. Our ecosystem is more complex than we ever imagined. As of last year our research efforts identified six different worms (one was a newly-discovered species!) with 3 different host birds in our watershed alone. So what else have we learned and what can we do to avoid the unpleasant side effects of exposure? The snails that shed the itch-causing worms live on the bottom and need light to survive. In the ever clearer waters of our lakes they have been found in water up to 8 feet deep, so swim very deep! The light seeking worms are shed by snails in the morning, quickly moving to the surface where they hope to find their preferred bird host. Avoid swimming before noon! Preferably swimming after 4 pm when worm numbers will have dropped significantly. The worms concentrate in the upper 18-24 inches of water and are easily moved by wind. Do not enter the water if there is an onshore wind at your location. The wind can accumulate very high numbers of worms at the shore. Some swimmers have reported application of waterproof sunscreen or baby oil before entering the water and applying hand sanitizer and/or vigorously toweling off when leaving the water to be helpful. But not all worm species are created equal and given the wide variety of itch causing worms in our watershed these methods are only partially effective.
So after all that, what can you do if you still get “the itch”? Treat it just like you would an annoying batch of mosquito bites. Avoid scratching! Scratching or breaking open the skin will increase the itchy sensation, prolong recovery and can lead to a secondary skin infection. Use a topical itch relief product such as an ice pack or hydrocortisone cream, calamine lotion or other anti-itch cream. Take an
oral anti-histamine such as Benadryl for general itch relief. Remember that while in more severe cases the “spots” can remain visible for weeks, the itchy sensation should subside after a few days with no lasting effect. Take appropriate measures to “Swim Smart” and keep enjoying the water!
It has been said that, “if you want to go quickly, go alone – but if you want to go far, go together.” It is widely believed that the Leelanau Conservancy has been and continues to be a wonderful and vital partner in our mission to preserve and protect our watershed. They use tools like “conservation easements” and “donated land” that turn into preserves to help us protect our surface and groundwater resources.
For example, the Leelanau Conservancy has helped us preserve a large part of the wetlands that make up our Hatlem Creek Preserve sub-watershed which affords clear, clean water flowing into Big Glen. Further, the Palmer Woods Preserve in the uplands of our watershed has been managed in such a way that it will be protected from development thereby protecting valuable groundwater that ends up in our lakes. In addition, some of the Crystal River Wetlands are now protected from development and combine with the boundaries of the national park giving our delicate Crystal River the protection that it deserves as evidence by the clear water that some of us take for granted.
The conservancy also can work with individual landowners in our watershed in an effort to preserve the natural shorelines that filter out excess nutrients that can cause our lake to deteriorate. If you would like to consider a “conservation easement” (a legal agreement between a landowner and the conservancy that permanently limits a propter’s use in order to protect its conservation values) for your property, why not consider setting up a meeting with their staff and consider how you, too, might contribute to the mission of preserving and protecting our watershed.
Bring a neighbor or friend to our annual meeting Saturday, August 10. The program will include the state of the lake report, a brief business meeting, strategic plan update and recognition awards. Lunch will follow and there will be free wildflower seed bombs for all!
Held at the Glen Lake Community Church, 4902 W. MacFarland Rd. in Glen Arbor, the meeting begins at 10 am.
The Glen Lake Association is a member of the Cooperative Lakes Monitoring Program (CLMP) which is a volunteer inland lakes water quality monitoring program. Every week during the summer volunteers measure water clarity (secchi disk visibility depth) and at various specified dates sample for phosphorus and Chlorophyll. We measure and sample on Big and Little Glen, Brooks, and Big Fisher lakes.
The CLMP website has data on Big Glen data going back to 1979 for secchi depths and to 2001 for chlorophyll and phosphorus. Water clarity has been improving on Big and Little Glen giving it that look of the blue Mediterranean. You might think this is a good thing, but maybe not Clarity is affected by suspended solids and algae. We believe clarity is increasing due to the removal of zooplankton and algae by zebra or quagga mussels. This means less food for small fish and greater depth where aquatic plants can grow. Our lakes have a lot of mussels. When we do our yearly invasive aquatic plant survey, we often bring up small mussels attached to the plants.
The following chart shows the numbers.
Phosphorus levels for Big Glen are averaging about 4 parts per billion over the last 18 years, dropping slightly. This is very good, indicating that we don’t have a lot of fertilizer or septic runoff into the lake. Some phosphorus is essential for plant and algae growth which is food for fish. Our level is very low.
Chlorophyll is the pigment that allows plants (including algae) to use sunlight to convert simple molecules into organic compounds via the process of photosynthesis. Measuring chlorophyll concentrations in water is a surrogate for actually measuring algae biomass.
The chlorophyll has been steady at less than 1 part per billion for 18 years. These are very low levels which indicates little fertilizer and septic runoff.
In some lakes, as septic systems get older and homes are upsized and lived in for more of the year, phosphorus and chlorophyll levels ramp up. This has not happened to Big Glen. The same is true for Little Glen, Brooks and Big Fisher lakes.
For the last 30 years, controlling Swimmer’s Itch used to be more simple – one duck, one snail, one parasite. Break the life cycle of the parasite that uses Common Mergansers and Stagnicola snails and you’re on your way to having a respectable lake-wide control of Swimmer’s Itch.
Unfortunately, based on last summer’s outbreak of itch despite our efforts, we now fear that itch on Glen Lake it is no longer that simple.
– Are other ducks, geese or swans contributing to the itch by serving as hosts to multiple species of itch causing worms?
– Are migrant waterfowl in the spring and fall contributing to the itch that undermines the effort of trapping and relocating resident merganser broods?
In order to unravel the mystery of the complex issues surrounding Swimmer’s Itch, we need to conduct weekly waterfowl surveys on Big and Little Glen lakes.
Waterfowl Survey Defined:
What does a waterfowl survey entail? Our surveys include weekly boat rides around the shoreline where we record the numbers and locations of any ducks, geese, and swans. Also, we attempt to collect fresh fecal samples of the waterfowl on docks, analyze the samples in the lab, and determine which parasite is in what bird (there are at least five different parasites that cause itch in our lake).
Three surveys have been completed so far. The surveys will continue throughout the summer and end the first week in November. GLA has developed a three-member waterfowl survey team that includes Rob Karner, Watershed Biologist along with our summer intern Cecelia Denton and our GLA assistant for water quality studies Laura Wiesen.
It is our hope that the waterfowl survey, together with the water sampling program that was mentioned in the last email blast, along with the help and expertise of Freshwater Solutions, the mysteries of Swimmer’s Itch will be solved. Stay tuned in December of 2019 for a full report of our findings and what it may all mean for managing Swimmer’s Itch in the future.
For more information, contact Rob Karner at email@example.com.
Cecelia Denton and Laura Wiesen are part of survey team.
With much enthusiasm the GLA shares the news that Tom Porter of the Sleeping Bear Dunes
Gateway Council/Citizens Council of the Sleeping Bear Dunes, will speak at the by invitation Legends* event on June 27. Tom will speak and take questions on the topic of gateway communities
such as Empire and Glen Arbor, in relation to the Sleeping Bear Dunes National Lakeshore.
As a founder of the Michigan Climate Action Network, Tom has been a leader in the push for clean energy solutions that promote climate sustainability. We hope Legends will mark their calendars and join us to hear this
Last summer something very unexpected happened on Glen Lake. The number of Swimmer’s Itch cases far exceeded what was suppose to be a banner year for mostly a itch-free swimming experience.
Using a federal and state permit, in 2017 the GLA removed all broods of mergansers.That should have resulted in a significant reduction in Swimmer’s Itch in 2018. Granted, the very warm, sunny summer resulted in increased swim hours and may have contributed to increased itch. Consequently, a lake-wide increase in itch has prompted a scientific study to find out what is going on.
Glen Lake Association in conjunction with Lake Leelanau and Walloon Lake Associations are the three locations for a major Swimmer’s Itch research project that will be conducted by Freshwater Solutions, Inc.
Each lake association is staffed to have 5 volunteers from each lake collect 10 different water samples on the same day (Tuesdays) and the same timeframe (between 8 a.m. to 12 noon) May 21 to November 5, and from the same locations on the lake. Quick math indicates that is 15 volunteers working for 25 Tuesdays collecting 750 water samples.
The volunteers for GLA include Cecelia Denton, Shelly Water, Edward Gergosian, Andy Dupont, Dale DeJager, and Bill Meserve. Joe Blondia, Bruce Hood, and Rob Karner will serve as the back-up support for the water sampling.
Each water sample will be analyzed for the number of parasites in the water sample, noting the number of species of itch causing worms in the water and their relative abundance for each species. Our ability to analyze water samples in this way is new technology and all analysis of parasites is under the direct supervision of Dr. Hanington and his team at the University of Alberta, Canada.
The final results of this study will help us better understand the impact that migrating waterfowl have on itch severity, along with gaining a better understanding of what additional species of waterfowl besides the Common Mergansers are harboring itch-causing parasites and perhaps unknowingly contributing to increased Swimmer’s Itch risk.
Having removed all Common Merganser broods last summer, we are hoping for lake-wide reduction in itch this summer.
GLA will be sharing a summary report of this study for all three lakes by the beginning of 2020.
We asked landscaping professional, Laurel Voran, left, to share her insight to help make your spring planting choices carefree and fruitful. Voran, who has enjoyed gardening her entire life, has worked in the field professionally for 21 years. She worked at two public gardens near Philadelphia including Longwood Gardens, where she studied and graduated from their two-year professional gardener training program, and Chanticleer gardens as a section horticulturist for 13 years. She has seven years running her own local business after relocating to northern Michigan. Her business includes work in garden maintenance and design, and invasive species monitoring and control. Voran also especially enjoys working with and “saving” our endangered species, like the Michigan Monkey Flower. Although working primarily with private clients, Voran also does work at the Botanic Garden at Historic Barns Park. She loves the artistic and creative nature of her environmentally-focused job that keeps her active outside.
Here’s her advice for spring planting:
To develop a natural, northern feel to your property, start by working with what plants are already present. Edit out the non-native competitors, encouraging already present natives to multiply. If you can’t wait for them to multiply on their own, plant more of whatever is already naturally occurring. If there are non-native plants you feel you can’t live without, choose ones that are adaptable to our soils and conditions and that are “well behaved.” Remember, plants spread not just by roots or by flowers going to seed, but also by berries or other fruits eaten by birds, digested and then the seed eliminated elsewhere- perhaps quite far from the original plant. Also, seed pods hitch-hike to new places in animal fur – and on human feet!
Reconsider the urge to clean up every leaf. Look for areas where you can mulch-mow leaves in place before the perennials emerge. Or lightly rake only the largest wads off. Perhaps there are areas you can allow to return to woods – first step: just let the leaves accumulate. It’s free organic matter that feeds the soil, and ultimately the plants, and helps keep roots cool, retains moisture in the soil, and helps keep weeds down.
Keep the water clean! Plant species that will thrive without fertilizer. Choose plants with extensive roots that will help stabilize soil along the water’s edge. Create a “no mow” zone directly next to the water rather than mulched beds or mowed lawn to the water’s edge. This will help slow and filter run-off prior to entering the open water, as mulch in beds close to open water could wash in during storms.
Educate yourself on what plants are considered non-native invasives. Search your property for any existing populations and remove them, as they out-compete our native species critical for supporting our native critters. Be aware that non-native invasive plants are, unfortunately, still for sale. Educate yourself so as to not accidentally introduce invasives to your property by purchasing them at nurseries.
As for plants, here are some of Laurel’s top choices for varying sun/shade locations and moisture conditions.
Dry Sun: Coreopsis lanceolata (sand coreopsis); Butterfly weed (Asclepias tuberosa); Little Bluestem (Schizachyrium scoparium); Spotted beebalm ( Monarda punctata). These will attract many pollinators!
Wet sun: Brown Fox Sedge (Carex vulpinoides); Marsh marigold, at right, (Caltha palustris); Sandbar willow (Salix exigua) and Pussy willow (Salix discolor), which have good roots for stabilizing soil. Can keep low by cutting to ground. Also, Joe Pye Weed (Eupatorium maculatum).
Dry shade: Spring ephemerals: Trillium, (Trillium grandiflorum); Dutchman’s breeches (Dicentra cucullaria); Spring beauty (Claytonia virginica; Bluestem goldenrod (Solidago caesia); Big leaf aster (Eurybia macrophylla); Ivory sedge (Carex eburnea).
Wet shade: Purple Joe Pye Weed (Eupartorium purpureum); Great Blue Lobelia (Lobelia siphilitica); Bottle Gentian (Gentiana andrewsii); Winterberry (Ilex verticillata).