Story URL: http://news.medill.northwestern.edu/chicago/news.aspx?id=131179
Story Retrieval Date: 10/25/2014 5:13:22 AM CST
Flimsy cottonwood trees shimmy in the breeze atop a sandy hill. Brown tipped grasses cover the gently sloping sand below, holding it in place as the lake winds blow through. Sandpipers and terns poke at the ground as soft waves lap at the shore. The drone of traffic rushes in the distance.
Created in the 1930s, Montrose Point was built with sand shipped in from Indiana. Now it hosts a harbor, a bird sanctuary, a beach, a dog park and Chicago’s only naturally formed sand dune.
“We are standing in the city of Chicago,” said Susan Tyma, a restoration volunteer at the dune. “You almost forget you’re in the city, you’re almost totally out in the wilderness.”
Feet planted in sand, Tyma gazes across 11 acres of the dune that are framed by two concrete walkways, a public beach and the lake. This place is an “example of how the earth can heal itself if you just let it,” she said. A glitch in beach maintenance started the progression from artificial landscape to one of the most natural areas in the city.
Chicago Park District sand groomers usually drag rakes across the Montrose beach each day to keep the sand flat and clear for visitors. But they stopped raking the eastern section of the beach 10 years ago – for reasons that aren’t entirely clear but have nothing to do with ecology. Soon after, a clump of high grass-like stems caught the eye of a volunteer steward. The grass-like Lakeshore rush had not been seen in the city for 50 years and revealed the potential for a dune.
After that all it took was a fence.
The park district divided the beach: sun bathers, their vehicles and dogs on one side, Mother Nature on the other. Protected from human and canine disruption, the dune ecosystem began to develop on its own, said Becky Schillo, volunteer stewardship coordinator for the park district. Native plants and animals, some rare and endangered, began to show up with only a few plantings by the city to speed the process.
Tough sprouts of sedges, asters and grasses began to appear. Seeds of these dune-adapted species were either washed or blown into the area from nearby ecosystems or had lain dormant in the soil all these years, Schillo said. The closest relic dune system is about 45 miles away at Illinois Beach State Park.
Spiky green tufts of grass now cover the sand at the Montrose dune. It is mostly marram grass, a plant crucial in dune development, said Schillo. Taking root in unstable soil is difficult enough but these grasses can be buried in sand and continue to grow. A web of underground stems, or rhizomes is formed which holds the sand in place and allows the dune to grow as well.
Between the cottonwoods and the lake is a low, flat area bristling with darker, reddish grasses. Natural occurrences of flooding created a dune wetland. This rare ecosystem known as a panne is found only around the Great Lakes. Assessments by the Illinois Department of Natural Resources estimate less than 200 acres of this habitat remaining in the world.
Two acres of panne helped earn the dune recognition as an Illinois Natural Areas Inventory site when five plant species listed by the state as endangered were found, according to the department of natural resources. The dune was also named an Important Bird Area by the National Audubon Society.
More than 150 bird species have been seen in the dune alone. The blue grosbeak, a small blue bird with chestnut wing markings was the most recent surprise added to the list, said Joe Lill, vice president of the Chicago Audubon Society. Sandy scrub habitat provided by the dune is not usually associated with the beaches of Chicago, he said. Its presence now invites an increased variety of birds to stop and rest at Montrose on their migratory route.
“There are always surprises,” Lill said.
Just recently 13 American avocets were seen strolling along the shoreline, he said. A rusty hue runs down the birds’ graceful necks into striking black and white wings on top of spindly legs. Searching in the shallow water with long, upturned beaks the large shorebirds are typically found farther south and west.
While the area does not provide enough room for many birds to nest, the quiet beach offers a place to refuel and recharge, Lill said. Before the fence went up, the constant flow of people and dogs would flush out birds trying to take a break on their long journey.
Chances of seeing birds like these avocets 10 or 15 years ago on this beach would have been nil, he said. Now they are there morning and evening.
Having even a postcard size of natural habitat is very important, said the park district’s Schillo. It also poses challenges to the healthy ecosystem.
“People say, ‘If it’s a nature area can’t it just take care of itself?’” Schillo said. If all of Chicago were a functioning ecosystem, then natural processes would occur regularly. Fires would roll through every so often and the dune itself would blow out completely every century. The surrounding manmade landscape not only prevents this but provides a smooth entrance for invasive species. Non-native plants could do real damage in just a few years without management.
Luckily, nature connoisseurs are happy to spend a Saturday pulling weeds at this city treasure. It has become a reminder of a time when ragged grasses and low mounds of sand were the norm.
“[Montrose] is only unique because all the dunes that used to be in the city were destroyed as the city grew,” said Michael Chrzastowski of the Illinois State Geological Survey. “They have all been bulldozed away.”
At only 8 to 12 feet high, the dune systems on the western shores of Lake Michigan are unimpressive compared to dunes towering hundreds of feet in Indiana and Michigan.
“On this side of the lake our winds are primarily blowing away from shore,” Chrzastowski said. “In order to build large dunes you have to have winds blowing on shore.”
Today’s lower lake levels also provided the opportunity for the dune to form, Chrzastowski said. There is a very large beach now but if lake levels should rise again we may see erosion into the dune.
For now volunteers gather at the Montrose dune at least once a month to monitor the “happy accident,” remove invasive species and plant the occasional tree or shrub. Tyma was quick with stories recalling the surreal sight of a three-foot-tall blue heron walking down the shore and the “single mother” fox with two cubs that built a winter den in the sands of the dune.
Tyma began picking up trash at the dune, her “summer home,” seven years ago. After being recruited as a volunteer she continued her clean up work.
“I wanted my summer home to look nice,” she said.