Spring 2001

Here's what's debuting this season on nature's stage in Chicago Wilderness

by Jack MacRae

EARLY SPRING

Northern Pike. While most of our large land predators are long gone their aquatic equivalents are still around. We have massive northern pike lurking in the shallows of our rivers and lakes, ready to ambush an unsuspecting fish. During the spring, a large, 3-foot long female will lay many thousands of eggs, randomly strewing them through he emergent vegetation. She has no further parental responsibilities.

The spawning areas found in the backwaters of the Des Plaines River have a long-standing reputation for producing untold numbers of large pike. The scientific name for pike, Essox lucius, is Latin for pitiless water wolf, a testament to their hunting talents.

Platform Appeal. A very cool event happened a few years back. A pair of ospreys decided that one of the many sloughs in the Palos forest preserves would be a nice place to raise their young. While these birds of prey were initially attracted to the site by the natural habitat, what most likely convinced them to stay was the artificial nesting platform that had been constructed and erected by the good people at the Forest Preserve District of Cook County.

The osprey couple will probably arrive in early April and add a new layer of dead sticks to the last year’s nest. They obviously feel secure in this location; the pair fledged three young in 1998, two young in 1999, and three young last spring. Area birders feel this may be the first productive osprey nest in the region for five decades.

MIDDLE OF SPRING

One Good Tern. After spending the winter in Central and South America, a few black terns will return to our area around the start of the baseball season. They will

construct their nests on the floating mats of decaying vegetation, with the mother depositing her eggs on the damp, spongy platform. After a few weeks of incubation, the young terns will hatch and be swimming about, watching their parents grab small fish and insects for their meals. Young terns are fed fish early in their life for added protein, but will usually switch to an insect repast as they grow up. While they used to breed throughout Illinois in the pre-settlement prairie marshes, today only a few high quality wetlands in our area are home to black terns, notably Lake Elizabeth in McHenry County and Broberg Marsh in Lake County, Illinois.

The List of Avian Visitors. I think it would be great if International Migratory Bird Day, this year on May 21, were as well celebrated as St. Patrick’s Day, where we exalt the exploits of a reputed snake killer. During the annual migration last year, spring visitors to the Chicago Wilderness included such colorful birds as the purple gallinule, the ruby-throated hummingbird, the blue-headed vireo, the scarlet tanager, and the black-throated green warbler. It’s a great day to get out and enjoy the multi-hued spectacle.

Awfully Cute. An adorable sight in the natural world is watching the young pied billed grebes taking a ride on the back of their mother. Mom can submerge like a submarine and, with her young clinging tenaciously to her back, she will

swim under the water in search of small fish and crustaceans. Grebes will build their nest in our high quality wetlands, along the water line, where they inevitably end up covered with duckweed and other nature — that looks like pond scum to many. The Lake Calumet area, with its vast expanse of marshy areas, is a fine place for these uncommon birds to raise their families.

END OF SPRING

Cartoon Educators. Bart Simpson’s teacher at Springfield Elementary School is Edna Krabapple. She may be named for the native Iowa crabapple, currently in bloom with their fragrant pink blossoms, growing along the edge of our woodlands. The not quite equally beautiful flowering crabapples in our neighborhoods are native to other lands, originally found far away across the seas.

From "Calvin and Hobbes" we have Ms. Wormwood, Calvin’s nemesis. I think she’s probably named for dragon wormwood, a close relative of tarragon and one of over 330 plants found on the Illinois list of endangered flora. While dragon wormwood had been recorded as occurring in Lake County, it may have been extirpated from the region, although not by Calvin.

Lifeline. It can’t be easy for a mother hoary bat to give birth to twins while hanging by her toes in a tree. To perform the feat, the mother maneuvers her body to hang in a horizontal position, clinging to a branch with her thumbs and feet. During delivery, mom will use her wings to support the tiny, naked pups. Within minutes, she will resume her usual head down position, cradling her babies and grooming them until they are clean and dry. For the first few hours after giving birth, the placenta acts as a lifeline to the newborn. One researcher saw a newly born hoary bat fall from its mother, only to crawl up the umbilical chord to safety.

Hoary bats are the largest, fastest, and most widespread bats in North America. Though not common, there are reports of them from Waterfall Glen and other forested areas in the Chicago Wilderness.