By Marty Corfman
[from fall 2024 newsletter]

I recently had the pleasure of attending a Zoom meeting for the Audubon Upper Mississippi River Network. There was some discussion about Chimney Swifts that led me to research their nightly roosting habits. A couple of weeks later, my husband and I were driving past Wartburg Theological Seminary in Dubuque at dusk, and I heard and saw many swifts hunting insects in the sky. I said, “Pull over, honey! This is gonna be cool!”

My unsuspecting hubby went along with his crazy birder wife, thank goodness. Having just learned about how swifts sometimes roost in swarms in broad chimneys, I was hoping my intuition was right. As the light faded, hundreds more swifts accumulated in the sky and began a circular swarm around the chimney. Soon a few birds here and there would drop into the chimney by raising their wings above their backs and dropping straight down. Inside they cling to the walls with their feet, using their peculiar spiny tail feathers as props. In the last 5 minutes of dusk, the sky blackened above the chimney with my estimate of 1,500-3,000 birds (impossible to tell!) and we could see them rapidly dropping into the chimney.

Suddenly the sky was empty and their loud twittering voices were silent as if they’d never been there. It was a magical experience, and I was so happy to be able to plan a “pop-up” birding outing for the next night. The swifts are migrating to South America right now, so I thought we’d better meet quickly, and 15 people came to experience this thrill! I’d say only about ½ as many birds were present as the night before. Keep your eyes and ears open at dusk in the fall and maybe you, too, can share in this spectacle of nature.

[The popup event was held on 9/5/24.]

Photo © Ken Kiss
Wartburg Theological Seminary
Dubuque, IA
9/5/24