chimney swift

Chimney Swifts: the experts of movement

Chimney Swifts: the experts of movement

What draws most people’s attention to Chimney Swifts in the fall is their incredible roosting behavior. Chimney Swifts spend 90% of their lives flying—only pausing their lives on-the-wing to roost and to nest. They eat, sleep, mate, and bathe while flying. In migration, flocks of Chimney Swifts roost in—you guessed it—chimneys, clinging with their feet to the walls while they sleep.

Photo by Steve Benoit FCC

Chimney Swifts are on the Move!

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As we turn the corner into September, bird-watchers look to the skies. Birds of all sorts are on the move, some new to migration or making the return trip yet again. Soon, warblers will begin migrating from northern Wisconsin to Central America, bugling sandhill cranes will make their way to the Gulf Coast, and American kestrels will take the short trip to Illinois.

One delightful species joining in migration is an acrobatic bird that puts on a dazzling show most August and September evenings. They’re easy to identify, because they form swirling funnels of small, chattering flappers, circling around a chimney in the sunset.

Then, as the sun drops below the horizon, they start dropping in -- a smoking chimney in reverse.  

These incredible birds are chimney swifts, a native summer breeder in Wisconsin that is now making its long trek to South America for the winter.

About Chimney Swifts

Chimney Swifts are dark gray-brown, swallow-like birds with long, slightly curved wings and stubby tails. They fly with stiff, rapid wing beats. Their call while in flight is a series of quick, chittering noises. The swift’s nickname is a “flying cigar” because of its short 5.25” body and its 12.5” wingspan.

This small bird spends almost its entire life in flight, feeding and drinking on the wing. Swifts help keep insect numbers in check and eat up to half their weight in flying insects each day! Chimney Swifts nest and roost in chimneys, concrete silos, and in other enclosed vertical masonry.

Nesting chimney swift, photo by Nancy Naback

Nesting chimney swift, photo by Nancy Naback

Unfortunately, Chimney Swift populations are declining throughout North America. One reason for this decline may be that fewer chimneys remain uncapped and available as habitat. Our chimneys are their homes — they return to the same chimney each year and are dependent on us to provide nesting and roosting space.

Learn more about chimney swifts and see them in action in our August 29, 2020 video of A Swift Night Out Online (originally streamed as a Facebook Live video):


A Swift Night Out Wisconsin

Each Fall, the Wisconsin Chimney Swift Working Group supports individuals and organizations throughout the state in hosting in-person events called A Swift Night Out. These events happen throughout North America, and are often big draws for community members and birders who enjoy watching and documenting these birds. Attendees report roosting sites and count and record how many swifts are using the chimney that night. Madison Audubon has hosted A Swift Night Out, led by Sandy Schwab, for the past 7 years, sometimes with 150+ attendees!

During the COVID-era, these big, wonderful events must take a different form. Because these birds are in decline and need attention and protection, Madison Audubon and the Wisconsin Chimney Swift Working Group created a new citizen science event called A Swift Night Out Wisconsin.

Wherever you are in the state, throughout the entire month of September,  you can report sightings of chimney swift roosts – and even better, count the number of swifts roosting there – using the free eBird website/app or by downloading and mailing in a datasheet.

By reporting roosting sites, you can help scientists and conservationists identify important sites to protect and restore, and better understand populations and movements of this wonderful species.

Learn more and join in at madisonaudubon.org/swift or https://wiswifts.org

Written by Brenna Marsicek, Madison Audubon director of outreach and communications, and Sandy Schwab, Wisconsin Chimney Swift Working Group chair

Chimney Swift

Want to see chimney swifts in action? Join us for
A Swift Night Out tonight, Sept. 1, 6:30 PM at
Cherokee Heights Middle School in Madison!

Photos by Kent McFarland

Photos by Kent McFarland

Look!  Up in the sky! It’s a bird, it’s a plane, it’s a... flying cigar!?  The generations of people that grew up with Superman remember the opening statements of the 1950s TV show, except perhaps for the "flying cigar" addition. What the heck are we talking about? Chimney swifts, of course!

We always enjoy observing chimney swifts (aka flying cigars) as many bird watchers do, with their aerial acrobatics and almost constant friendly chattering calls.  One friend even has “chimney swift” in their email address.

Photo by Joni Denker

Photo by Joni Denker

Chimney swifts have been in a long-term, range-wide decline of about 2.5% per year between 1966 and 2015, resulting in a cumulative decline of 72%, according to the North American Breeding Bird Survey. The Partners in Flight group estimates a global breeding population of 7.8 million, with 99% breeding in the U.S., and 1% in Canada.

Chimney swifts spend their lives mostly airborne, except when they are roosting or on the nest. We have seen thousands of chimney swifts over the past decades and this is one bird that we have never seen perched.

These birds originally nested in caves and hollow trees found in old forests, they probably became much more numerous with European settlement and the building of millions of chimneys. However, traditional brick chimneys are now deteriorating and modern chimneys tend to be unsuitable for nest sites. Adding to the problem, some homeowners now cap their unused chimneys.  Chimney cleaning during the nesting season can inadvertently destroy nests and kill swifts. Logging of old-growth forests can reduce the availability of natural nest sites. Only one pair nests per chimney. Below, you can watch chimney swifts flying around their roost at last year's A Swift Night Out (this year's is tonight!).

During our current breeding bird atlas work, we surveyed all the villages, towns, and cities in Columbia County and found swifts in all communities. Atlas volunteers are observing a few birds in the county but chimneys are hard to locate. We were lucky to find an old one-room school house with a nesting pair. 

We confirm nesting by seeing swifts enter chimneys during the day in the breeding season and also by seeing swifts breaking off twigs from dead limbs for nest building while in flight. The current breeding bird atlas has photos of two swift nests: one in a chimney in Grant County, and one in a silo near Poynette found and photographed by Michael John Jaeger.

During migration chimney swifts forage in flocks over forests and open areas and roost in large numbers chimneys at night.  There’s warmth in numbers: during cold nights, the temperature inside a chimney roost can be 70°F warmer than outside.  

They spend the winter in the upper Amazon basin of Peru, Ecuador, Chile, and Brazil, where they are found in open terrain and on roosts in chimneys, churches, and caves.

Photo by Susan Foote-Martin

Photo by Susan Foote-Martin

We tried to help out our fast flying friends by erecting a chimney swift tower at our cabin and also at Goose Pond Sanctuary.  However, we have not been successful in attracting a nesting pair.  If you would like to learn more about these amazing birds, visit the Wisconsin Chimney Swift Working Group's excellent website: www.wiswifts.org

Madison Audubon Society invites you to participate in A Swift Night Out (see below). We are looking forward to counting chimney swifts at a small nearby community with a large, unused brick chimney.

Written by Mark Martin Susan Foote-Martin, Goose Pond Sanctuary resident co-managers


Photo by Joni Denker

Photo by Joni Denker

A Swift Night Out

Tonight is the Fifth Annual "A Swift Night Out" sponsored by Madison Audubon!  A Swift Night Out is a continent-wide effort to increase awareness of swifts and their habitat. At the end of summer, swifts begin gathering in large groups in large chimneys prior to their migration to the Amazon basin. Watching a flock of swifts descend into a chimney is an incredible natural phenomenon. Identification and preservation of these roosting chimneys is very important in preserving this species. The data gathered from A Swift Night Out events (number of swifts, location of roost chimney, and other details) is entered in eBird and at www.chimneyswifts.org

I became smitten with chimney swifts seven years ago as a volunteer at Dane County Humane Society's Wildlife Center. I realized that these amazing birds are beneficial to us (they help keep our insect population in check and they entertain us with their graceful flight) but they also need our help. I chair a state-wide group (WI Chimney Swift Working Group) that seeks to educate the public and help keep the Chimney Swift a common species in Wisconsin. 

I hope you'll join us tonight -- I'll be your host and tour guide as we watch these fabulous flyers in action!

Written by Sandy Schwab, Madison Audubon field trip volunteer