Seven people in warm coats and with binoculars, smiling at the camera, standing in front of a brick wall.

words by Steve Whitman

Rain delayed the start of the Oct. 19 Humboldt Park Sunday Social Bird Walk, led by COS board member Chris Holden, but the weather conditions turned out to be fortuitous for observing birds.

At the boathouse parking lot, the first birders to arrive immediately noticed a kettle of 40 Turkey Vultures riding a thermal updraft in the northeast corner of the park before soaring their way south. As Holden explained to each birder who arrived, the northwesterly winds and recent cold front created ideal migratory conditions for birds, especially raptors like the vultures.

Very large bird with wings spread wide against a blue sky, seen from below. The bird had a black body, tail and front edge of the wings, white feathers on the back edges, and a naked pink head. — Turkey Vulture. *Photo by Walter Marcisz, Burnham Prairie, May 16, 2017.*

After the rest of the six birders in attendance arrived, Holden led the social group in an ice breaker and introductions. “How many species of birds do you think we will see today?” was his question, and since the fall migration season was winding down, the highest estimate was only 25 species.

From the boathouse terrace, an American Kestrel was seen mobbing a Cooper’s Hawk that was perched on a tree near the lagoon. Canada Geese, Mallards, and several Wood Ducks waded in the water below. The hawk was unfazed by the smaller falcon, and another Cooper’s Hawk arrived and perched nearby. The kestrel persisted, harassing both hawks now.

Holden explained that the kestrel’s swooping harassment can be observed in several species and that, when seen, birders should seek to notice whatever predator is being mobbed.

Holden then led the group north towards the scene for a better look. He called the location of the perched hawks “Grackle Island Party Zone,” and by the time the group approached, a Red-tailed Hawk was now perched in the same tree. The kestrel’s harassment had ended.

At the protected natural area, Holden helped the group get on and identify Yellow-rumped and Palm warblers in the shrubs and trees, and Song and White-throated Sparrows on the ground and fencing. Eventually, Holden pointed out an Orange-crowned Warbler. A lifer for multiple birders!

Small slender-bodied bird with olive head and back, plain yellowish belly, narrow white eye ring around a dark eye, and thin, short, sharp beak, perched high on some shrubby leaves. — Orange-crowned Warbler. *Photo by Ima Akagawa, Burnham Corridor, Oct. 9, 2024.*

Traveling along the north side of the lagoon, a Belted Kingfisher’s rattle call was heard. The bird was seen flying just above the water and then perched on a wooded island tree. Near the playground, the group saw Golden-crowned and Ruby-crowned Kinglets and an Eastern Phoebe. Holden pointed out a flock of about 20 Dark-eyed Juncos. Closer toward them, he heard an Eastern Towhee and described (and demonstrated) their double-footed foraging behavior.

Holden then led the group across Humboldt Drive. Near the historic Fieldhouse, many more sparrows, including a Field Sparrow, were actively foraging on the ground along the path.

With the birds being so active and so numerous, the Sunday Social birders had a lot to talk about. The group’s conservative expectations were exceeded, having observed a total of 36 species.

Field trip recap: Humboldt Park Sunday Social