SAY A SMALL 'THANKS' FOR CHIMNEY SWIFTS

Chimney Swift - photo courtesy Sharon Milligan
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In the United States, the Chimney Swift is the eastern representative of a large family that occurs in all parts of the world except oceans and polar regions.

It is safe to say that between mid March and late October, if you are disposed to look you will see Chimney Swifts, regardless of where you live on the Coast. They are easy to recognize, by sight, by sound, by flight style and behavior.

These small flying machines are all-gray with the body shape of a cigar and the wing shape of a backward-curving scimitar. They make sharp, chittering sounds while flying. Their wing strokes are jerky and bat-like, but they also glide and sail on set wings. The operative word for their flight is FAST. Although swifts are gregarious, in the spring, we often see them in groups of three (two males in pursuit of a female, and only they know which is which). They are active all day, from sunrise until after sunset. Because of their flight style, and the late hours they keep, the uninitiated may mistake swifts for bats.

If you could hold a Chimney Swift in your hand, you would see things that aren’t visible as it streaks overhead like an SST (supersonic transport). For instance, it has very small, weak legs; should it happen to be grounded, it is likely to be a permanent grounding, for it is as a rocket without thrust.

Its bill is short, tiny and slightly down-curved. Its gape (its mouth opening) extends from under-eye to under-eye (the better for a record catch of flying insects). Its tail is short and stiff, with spiny tips, and its claws are strong enough to enable it to cling to rock walls and chimneys (with its spiny tail for support) for one long night after another.

Superficially (very superficially), swifts resemble swallows, but in fact they are more closely related to hummingbirds.

Chimney Swifts nest and roost in chimneys (also in barns, silos, cisterns, etc.). When this was the forest primeval, any dark, sheltered place, such as a hollow tree, would do.

Many people become familiar with Chimney Swifts on a summer’s night, when they hear a disturbance in the wall above the fireplace. Investigation into its source will reveal a nest inside the chimney, with several birds clinging to its walls. I’m always dismayed when I hear that someone has built a roaring fire in the fireplace to rid themselves of Chimney Swifts – and it happens frequently – often at the hands of the same people who cater to bluebirds and martins. If you are one whose tolerance for swifts is low, the more humane way is to wait it out for this year and then affix some hardware cloth, or screening to the chimney opening after the birds have fledged (Editor’s note: The Pascagoula River Audubon Centre which opened in 2015 uses purpose-built Chimney Swifts houses, and information can be obtained from there on how to build these.  See footnote)

The nest is an interesting affair, and work goes into it. Since swifts don’t perch on branches or land on the ground, they get nesting material while flying, using their feet to break off twigs. The twigs are cemented together and attached to the inside wall of a chimney, for example, with glutinous saliva to form a half-cup, which is unlined. The eggs (4-5, or sometimes as many as 6) are incubated by both parents for 19 days.

Newly hatched young are naked and blind, and they are fed a diet of insects, carried in the throat pouches and disgorged directly into their mouths, by parents and any available helpers. Young don’t open their eyes until they are 14 days old. They leave the nest and cling to, or climb on, the walls as early as 19 days, always upward, towards the sky. They fly between their 24^th and 26^th day but return to the chimney at nightfall. That is why we see so much more swift activity in mid to late summer.

Chimney Swifts spend their daytime lives on the wing, food-gathering, courting, drinking, bathing, gathering nest materials and even copulating, which they also accomplish on the nest. They are constantly on the hunt for flying insects. You may become more aware of them after a long rain or a long cold spell, when insects that have been scarce suddenly become more available. A single swift may fly as much as 500 miles a day, generally in broad circles, during the nesting season. During its lifetime, it may fly more than a million miles, including migration flights to and from South American wintering grounds.

This article was published in 1992. Below is a comment from the Director of Pascagoula River Audubon Centre regarding his experience with chimney swifts:


 At the centre, we have only ever had one nest per chimney .Adults may tolerate the juveniles (their children) from previous years in the chimney when they return, but then run them out once egg laying starts.  Of course, after young are fledged, the adults will allow others to roost in the chimney.

Please do mention that we have three pairs of Chimney Swifts nesting at the PRAC: one pair each in the two constructed towers (one of which is sponsored by the MCAS) and a third in the chimney in the Scout Hut. And YES, please do mention the wonderful instructional videos available.

Chimney Swift Tower Construction - Part 1
https://www.youtube.com/watch?v=l2XWt6OZy_A

Chimney Swift Tower Construction - Part 2
https://www.youtube.com/watch?v=OJNo7tCUdQg

We continue to be available to help folks that want to build them. In addition to the videos, we sell the instruction book by Paul & Georgean Kyle that has step-by-step instructions that were followed in the videos.

Chimney Swift Towers: New Habitat for America's Mysterious Birds - A Construction Guide ($12.95)

You might also mention that the PRAC is in the process of developing a Chimney Swift monitoring network that links the towers up and down the Mississippi River as a means of tracking their ebb and flow during the year across their range.