Natural Events

By Jack MacRae

Here’s what’s debuting on nature’s stage in Chicago Wilderness

Early Spring

Regal Appointment

During his annual royal visit to the Chicago Wilderness, the little kinglet enjoys flashing his crown of gold. He confronts his adversaries by tilting his shoulders forward and raising the small tuft of orange and yellow feathers on the top of his head. What a show-off.

Golden-crowned kinglets are tiny grayish birds that seem to be in a constant state of agitation, flicking their wings every few seconds. They pass through our area during the middle of March and are gone by May Day, on their way to the evergreen palace north of the Great Lakes. There’s a single record of golden-crowned kinglets breeding in Illinois, from June 2003 — a pair that raised a family in a small grove of spruce trees on a hill at The Morton Arboretum.

Yellow-Headed Stranger

The male yellow-headed blackbird practices polygamy. He returns to his cattail home in late April, a short time before his female counterparts. When the girls finally arrive, he greets his prospective mates with humility; head bowed, wings out, rasping a variety of scratchy vocals. The ones he successfully impresses weave their over-water nests amongst cattails and rushes. They use wet vegetation for the warp and weft, which will dry and bind itself tightly to the upright supports.

Yellow-headed blackbirds are primarily a western bird. One of the largest populations of nesting yellow-headed blackbirds east of the Mississippi River is in the Chicago Wilderness. These beautiful, state-endangered birds can be found in large marshes throughout the region.

Middle Spring

Green Party

When male and female smooth green snakes mate during May, it’s an affectionate affair, often taking place in the romantic confines of an anthill. A few weeks later, with warm enough weather, the female will deposit small, elliptical, thin-shelled eggs in decomposing vegetation. If the weather stays cool, she may retain the eggs until conditions are favorable. In a few cases, the eggs have hatched while still inside Mom’s body, slithering out as they would in an animal that bears live young.

Late Spring

Largest Hardwood

Eastern cottonwoods are very, very big trees and one of the very, very biggest is growing in a quiet neighborhood in the quiet town of Downers Grove. Close to record size at more than 7.5 feet in diameter, it’s a real stunner of a tree.

Sexually speaking, cottonwood trees are dioecious, with male and female flowers found on separate trees. During the early days of spring, the male tree produces long reddish flowers, with stamens literally dripping with pollen. At the same time, the flowers of the female cottonwood elongate, forming a string of capsules that will enclose the seeds as they develop.

Toward the end of spring, the cottonwood releases white fluffy seeds in the showy display that earned the tree its name. It looks like a blizzard in June, with drifts of seeds blanketing lawns and piling up along curbs, alleys, and sidewalks.

Until recently, the big-tree national champion eastern cottonwood was the ten-foot-diameter beauty that grew along the Illinois and Michigan Canal in Grundy County. I visited that tree often, including the day after a June 1992 storm sadly brought it down.

Lake Sturgeon

I really believe that on some future June day, lake sturgeon will again spawn locally, slipping gracefully through our waters and occasionally breaking the surface like prehistoric porpoises. The future seems bright. In recent years, several hundred-thousand lake sturgeon hatchlings have been reintroduced into parts of the Milwaukee and Manitowoc Rivers. In addition, 200 yearling sturgeons have been reintroduced. It’s conceivable that a few could venture this way some year soon and perhaps stay for a while.

Local reports of sturgeon are rare. In March 2000, a fisherman caught and released a 45-inch lake sturgeon in Wolf Lake on the Illinois-Indiana border. According to its tag, attached on August 1994, this fine fish had a fantastic voyage that began in the Wolf River in northeast Wisconsin and ended in the Chicago Wilderness, more than 250 miles and countless obstructions away.