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U-M divers retrieve 8,900-year-old piece of wood from Lake Huron
Annarbor.com (12/12)
University of Michigan researchers announced they have found a 5 1/2 foot long, pole-shaped piece of wood that is 8,900 years old in Lake Huron.
Superior researchers studying invasives, ballast water
Ashland Current (2/9)
Determining how clean a ship's ballast water must be to prevent the spread of aquatic invasive species is the goal of the latest research partnership between the Northeast-Midwest Institute and the Lake Superior Research Institute at the University of Wisconsin-Superior.
RIVERKEEPERS: Tending the waterways
Niagara Gazette (2/6)
The goal of the Buffalo Niagara Riverkeeper is two-fold: protecting the water quantity and the quality, as well as connecting people to the waterfront.
Internationally renowned ‘Ocean Doctor’ to speak in Grand Rapids
MLive.com (2/3)
Known as the “Ocean Doctor,” David Guggenheim will speak in Grand Rapids, Mich., about the many similarities between the threats to the oceans and to our Great Lakes.
SUNY Fredonia to lead Great Lakes pollution study
Wall Street Journal (2/3)
Plastic pollution in the Great Lakes will be the focus of a study this summer. Led by the State University of New York at Fredonia, researchers will try to quantify the amount of plastic polluting the fresh water Great Lakes.
SSC students taking part in marine science bowl
Arenac County Independent (1/31)
Teams of Michigan high school students will be heading to Ann Arbor this weekend to take part in the annual Great Lakes Bowl, a quiz event that focuses on questions about marine and freshwater systems and biology.
What's going on in your neighborhood this month? Meet other people and learn together at recreational and educational events! Our new dynamic calendar is updated daily with current educational events.
3 | The sandy dunes
The sand dunes of the Great Lakes region represent the largest freshwater coastal dunes in the world. These dunes, such as the Sleeping Bear Dunes on the northeastern shore of Lake Michigan, are only 3,000-4,000 years old - that's very young, geologically speaking!
The Legend of the Sleeping Bear
How are dunes created?
Lake Michigan went through a stage of geological development where it was known as Lake Nipissing. Lake Nipissing's water levels were about 40 feet higher than they are today, creating many embayments at the openings of rivers. Eventually, sand from the rivers and currents created large sand bars that cut off the bays from the lake. Hamlin Lake in Michigan is an example of an inland lake that was once a bay in the Lake Nipissing time period. Lake Nipissing's water levels fluctuated greatly, much like Great Lakes' water levels do today; coupled with strong westerly winds, the sand bars were eventually sculpted into the towering dunes we see today.
Why are dunes important?
Sand dunes support a unique ecosystem, which develops in a succession, the process of one plant community replacing another over time. Pioneer grasses, such as marram grass and sand reed, "catch" blowing sand and help to build up the dune. Shrubs then take over the dune, such as red osier dogwood and sand cherry, and they stabilize the dune until trees are able to take root. Eventually, the dune will evolve into a forest. Dunes support a large habitat for native plants; the Indiana Dunes National Lakeshore ranks seventh among national parks in plant diversity!
Dunes are also the home for many endangered and threatened animals and plants. The piping plover, a small shorebird, nests in the shoreline sand, often in the protection of a perched dune. Houghton's goldenrod, pitcher's thistle, and the dwarf lake iris are all examples of threatened plant species that live on the Great Lakes dunes.
Are all dunes the same?
There are two types of dunes in the Great Lakes region: beach dunes and perched dunes. Beach dunes develop on the low-lying shores of Lake Michigan, and they consist mostly of sand. The Aral Dunes along Platte Bay on Lake Michigan are examples of beach dunes. Perched dunes, such as Sleeping Bear Dunes along Lake Michigan and the Grand Sable dunes along Lake Superior, sit on a plateau high above the shore. They consist of sand as well as other loose material, and dramatically changing lake levels help to create them.
Sand is used to make molds for cars, trains, and airplanes as well as glass and concrete products. Dune mining destroys a dune, and the sand that is obtained is a nonrenewable supply; once a dune is mined, it cannot be replaced. The Sand Dune Protection and Management Act was passed in 1976, but the Great Lakes region continues to lose many of its dunes, such as Pigeon Hill, Maggie Thorpe, and Creeping Joe, to dune mining.
Dunes are also threatened by tourism. Golf courses are often developed on dunes. And climbing dunes causes excessive erosion, damages native and rare plants, and can destroy nesting habitats for birds and animals. When hiking on dunes, it's important to stay on the designated trails!
Find out what you can do to help save the dunes, and visit GLIN's Dunes page for more information.
Also visit BeachWatch, Delicate Dunes and Grass That Holds Its Ground
Graphics: Sleeping Bear Dunes; Indiana Dunes National Lakeshore; Piping Plover; Pitcher's Thistle; Dune mining
