Bird migration is well underway, and the nesting season is upon us at the Lake County Forest Preserves in northern Illinois. I watched last week as an American robin (Turdus migratorius) plucked dried grasses from the yard, nudging them into place with her beak and wings, readying her cup-shaped nest for the azure eggs that are synonymous with spring. From the nearby American sycamore (Platanus occidentalis) tree, I heard the gurgling chatter of a flock of brown-headed cowbirds (Molothrus ater).
I thought about how while the robin might’ve seemed completely absorbed in her nest building, she was probably wearily listening to the cowbirds, too. Brown-headed cowbirds are North America’s most common avian brood parasite, forgoing nest building altogether. Instead, they lay their eggs in the nests of more than 200 other species of birds, leaving the incubation and rearing of their young to these unwitting foster parents.
Spring is the starting block for wildlife in the race to find suitable mates and nesting sites. With the increased flurry in wildlife activity, staff at the Lake County Forest Preserves in northern Illinois also get an increased flurry of phone calls with questions from the public. One recent call came from a gentleman in disbelief upon seeing ducks perched in his trees. He was utterly transfixed by the phenomenon. The call brought back a flash of memory for me of the first time I saw a wood duck (Aix sponsa) as a child, on my maternal grandfather’s property in northern Illinois. Grandpa “Duck,” as we affectionately called him, was an avid outdoorsman. He spent a few moments that spring day pointing out the distinct, vibrantly hued male and the more muted female near a nest hole in an old maple tree. The pair then took off into the woods to the soundtrack of their high-pitched whistling calls.