DNR – Dreaded Didymo – or “Rock-Snot”

December 6, 2021

The Michigan Departments of Environment, Great Lakes, and Energy and Natural Resources confirmed a report of Didymo, a pesky freshwater algae, in a section of the Upper Manistee River in Kalkaska County. Didymo, despite its coarse, woolly texture, is also known as boulder and can grow into thick mats that cover the river floor.

The discovery on the Manistee River marks the first record of Didymo flowers on the Lower Peninsula. In 2015, on the Michigan side of the St. Marys River near Sault Ste. extensive Didymo mats found. Marie on the upper peninsula.

“Didymo can be attached to fishing gear, wading gear, and other hard surfaces and relocated onto new waterways,” said Bill Keiper, aquatic biologist with EGLE’s water resources division. “With each new detection, it becomes more important for people fishing, wading, or boating to clean their boats and equipment, including waders, after each use.”

Anglers who have encountered Didymo-infested streams in the west or east of the United States know that rock spill is more than just a nuisance.

“Didymo has the potential to become a bothersome species in Michigan’s cold-water fisheries,” said Samuel Day, a water quality biologist with the Little Traverse Bay Bands of Odawa Indians. “Unlike the noxious algal blooms that plague Great Lakes areas from warm temperatures and excess nutrients, didymo flowers form in cold, nutrient-poor streams that most people generally consider pristine and great habitat for trout. Didymo can become a problem if it blooms, covers stream beds and reduces habitat for macroinvertebrates, which are an important food for fish. “

Didymo mats in Manistee River

Day, who was a PhD student at Tennessee Technological University Didymo in southeastern US creeks, discovered the algal blooms between the docks of Three Mile Bend and the Sharon Road Bridge on the Upper Manistee River while fishing with a friend on November 14th. Samples were his results forwarded to the EGLE Water Resources Division and then reviewed by Julianne Heinlein, a water ecologist and algae taxonologist at Great Lakes Environmental Center, Inc.

Since 2015, the Michigan Invasive Species Grant Program has supported researchers from the Center for Freshwater Research and Education at Lake Superior State University in a comprehensive study of Didymo’s occurrence in the St. Marys River and Upper Peninsula waters, the risk of spread and why Flatulence is increasing – a phenomenon that can be observed worldwide.

The discovery of the Manistee River suggests that the distribution of Didymo in Michigan waters may be more widespread than previously anticipated. The LSSU’s ongoing efforts will help meet didymo’s research and management needs across the country.

Didymo, a microscopic diatom (unicellular alga), can be found undetected in some bodies of water until changes in water quality cause it to “bloom” or develop long stalks that become visible on hard surfaces in the creek bed. A better understanding of the changes that blooms cause can also help combat the negative environmental impact of the species.

There are currently no effective methods for eradicating Didymo once it has established itself in a river or stream. To prevent the spread of Didymo and other invasive water species to new locations, it is critical for recreational users to thoroughly clean, drain and dry waders, equipment and boats when leaving a waterway.

  • Clean by removing mud and grime from all surfaces.
  • Drain the water from all bilges, wells, and tanks.
  • Dry the device for at least five days or disinfect it with hot water or a diluted bleach solution.
Didymo cells and stems enlarged

“Over the next few months, we will be working with partners to ensure that aquatic invasive species signs are posted at access points and to get the message across to the fishing community,” said Keiper. “We want to encourage local fly shops, fishing guides, and conservation groups to help by emphasizing the importance of decontaminating equipment and gear to protect these waters from Didymo and other invasive water species.”

If you see Didymo in the water, either as tiny, cotton ball-sized patches or thick blankets with rope-like strings flowing in currents, snap photos, record their location, and report them through the Midwestern Invasive Species Information Network available online MISIN.MSU.edu or as a downloadable smartphone app. The MISIN smartphone app takes a GPS location point when there is a report on site; It also allows you to upload photos with a report.

For more information about didymo and identification, see Michigan.gov/Invasives.

Michigan’s Invasive Species Program is jointly run by the Department of Environment, Great Lakes, and Energy, the Department of Natural Resources, and the Department of Agriculture and Rural Development.

/ Note to the editor: Accompanying photos are available for download below. The following are recommended captions and photo credit information:

hook: Didymo from the Upper Manistee River caught with gear. Photo courtesy of Samuel Day, LTBB.

Slide: A view of Didymo cells and stems through a microscope. Photo courtesy of Samuel Day, LTBB.

Manistee: Didymo growth on gravel in the Manistee River appears dark brown. Areas where thick vegetation is peeling off look woolly and light brown, exposing clean substrate underneath. Photo courtesy of EGLE.

Strands: Didymo strands on substrate in the St. Marys River. Photo courtesy of EGLE.

cell: A single Didymo cell enlarged. Photo courtesy Julianne Heinlein, Great Lakes Environmental Center, Inc./

Source link

About Ellen Lewandowski

Check Also

Angelo State University Expands Cybersecurity Presence

Tom Nurre Jr. Angelo State University was selected to work with the Texas Department of …