ABOVE: A chimney swift in flight. (Wikipedia Commons/contributed) 

Swiftnado alert!

No, you don’t have to seek immediate shelter. But if you are in the Birmingham area and want to witness summer’s swirling, twilight-hour aerial dance of thousands of tiny chimney swifts over the city, time’s running out.

Chimney swifts didn’t always roost in chimneys. The birds were around well before humans discovered they could pile up bricks in vertical structures that did wonders to keep the smoke out of their eyes.

At one time, swifts’ favored homes were inside hollow trees or in caves, where they built tiny nests, attached cleverly to the steep sides like mini condominiums.

Today, however, old chimneys are pretty easy to find, especially in urban areas. And swifts have adapted to them with a vengeance.

In Birmingham, the swifts start arriving in spring, but the peak time is mid-August to mid-October, before a chill in the air spurs them to shift south toward winter roosts in Central and South America. While they are here, they bulk up on insects, which benefits man as well as the birds.

This year, the chimney of choice in downtown Birmingham is atop the historic Boutwell Auditorium on Rev. Abraham Woods Boulevard. To catch the evening’s choreography, climb (or drive) to the top of the municipal parking deck next to the auditorium. The best place to watch is from the northeast corner of the deck.

Chimney swifts take up residence in a chimney. (Wikipedia Commons/contributed)

See the “swift” show

Come twilight, thousands of swifts will begin to converge from all directions, soaring and swaying in large groups over their chimney. Then, when the moment is just right, they dive into the chimney in a swirling, spinning mass – a swiftnado. By the time the light fades, they are all inside, settled and snug until daybreak, when they fly out for another day of feasting.

Last month, Birmingham Audubon Society conducted its now-annual swift count from atop the parking deck. Suzanne Langley, Birmingham Audubon executive director, said this year’s count topped 3,000. Impressive, except when you consider last year’s count – more than 7,000. In 2014, the preferred chimney in Birmingham was located about four blocks north.

Langley said it’s not clear why the swifts choose one chimney over another. They hope to learn more next year, after work is complete on a special chimney, being built just for the swifts, atop the nearby McWane Science Center. The chimney is a joint project of Audubon, McWane and the Birmingham chapter of the American Institute of Architects. “We hope the new chimney will help us get a better handle on some of their habits,” Langley said.

Langley noted that while the peak has probably passed for this year’s season of the swifts, there should still be a pretty good show for a couple more weeks. “A lot of it depends when the colder weather pushes through.”

So if you want to see the swifts, move swiftly.

In the meantime, you can watch this video as the swifts fly into a chimney in Bluff Park, taken a few days ago by Alabama NewsCenter’s Phil Free.

Bluff Park swiftnado from Alabama NewsCenter on Vimeo.