Natural History

Chimney Swifts are one of the most active birds in the world. They fly almost constantly during the day. You can hear them chittering during the spring and summertime as they fly high above, catching flying insects. They have been described as resembling a "flying cigar."

Chimney Swifts spend the winter in the Amazon Basin of South America, then travel here in the Spring to breed and raise their family. In the Fall, they congregate in large groups as they prepare for their migration trip back to South America. They use large older chimneys as roosts. Roosting groups can number as few as a couple of swifts or larger with thousands of swifts!

To learn more about Fall roosting swifts in your area and to take part in a national program that counts migrating swifts, A Swift Night Out, see these websites for more information: and SwiftWatch.

Here is a video of migrating chimney swifts going into a roost at night. This particular chimney is located in downtown Athens, GA.

YouTube Video

Chimney Swift nests are a half saucer shape of woven small twigs held together with their own saliva and glued with saliva to the inside wall of a chimney. The nest is about 4 inches wide by 1 inch tall. They typically lay 2-7 eggs. The eggs are incubated for 18-21 days by both parents. After hatching the young stay in the nest for 20 days. After fledging, they will stay in the chimney for another 8-10 days practicing flying. 30 days after hatching, they will take their first flight out of the chimney.

Here is a video of a chimney swift incubating eggs on the nest.
This video was taken by the Driftwood Wildlife Association, in
one of their chimney swift towers.
To learn more about swift towers follow this link.

Family Life
Chimney swifts are monogamous; records indicate that some chimney swifts will remain with the same mate for up to eight or nine years. Swifts are known to stay together as family groups. They have been seen migrating together and during the breeding season, young from the previous year will assist with raising the new brood. They are known as "helpers at the nest".

Here is a video of a chimney swifts going to roost as seen
from the inside! This video was taken by the Driftwood Wildlife Association. To see more of their videos follow this link.

Chimney Swifts used to nest in large, old, dead, hollowed out trees. Very few of these trees now exist and swifts have had to adapt to using human made chimneys as nesting areas. In the past this has worked out well for the swifts: they had an abundance of nesting areas available to them, and their population grew.

Unfortunately, in the past decade chimney designs have changed and many new chimneys can not be used by swifts to nest. Also, many older homes have put caps on their chimneys, which keep out the swifts. This has lead to a rapid decline in the swift population.

What Can I Do To Help Chimney Swifts?
If you have a masonry or clay flue-tile chimney, keep the top open and the damper closed from March through October to provide a nest site for these insect-eaters. Metal chimneys should be permanently capped to prevent birds and other wildlife from being trapped.

Have your chimney cleaned in early March before the Chimney Swifts return from their winter home in South America.

Work with local conservation groups to construct Chimney Swift Towers and educate your friends and neighbors about Chimney Swifts.

Birds In Your Chimney?
Find more information about living with chimney swifts, including how to deal with a fallen nest, at this link.

Swift Towers
During migration swifts are very social and can be seen in large flocks, but during the nesting season, only one family can nest per chimney. With a decline in swift friendly chimneys, some researchers are looking at creating artificial chimneys called "Swift Towers".

·        To learn more about their research, see this site.
·        To see examples of swift towers, see this site.
·        To see a book written about the topic, see this site.
·        This nest cam is located inside a swift tower in New York.