Bird of the Week: Chimney Swift

Many Chimney Swifts circling the top of a chimney. Photo credit: Ben Cvengros.

Chimney Swift (Chaetura pelagica)

The sleek, elegant, speedy Chimney Swift brings summer to life for many in the Texas Hill Country. Described by some as a “flying cigar”, Chimney Swifts appear as a dark gray silhouette playing across the sky. More closely related to hummingbirds than swallows, they have a tiny black body, curved wings and round head, making the bird very aerodynamic. The bird can also be identified in flight by its stiff wingbeats and fluid call.

Do not expect to see one of these swifts sitting still, because they neither perch nor walk along the ground. These birds are part of the family Apodidae, which translated means “footless”. Swifts were depicted in art and literature as creatures without feet until medieval times because of their quick speed and inability to perch. Instead, the small bird’s strong legs cling to vertical walls in chimneys, hollow trees, or caves.

In English poet Anne Stevenson’s poem “Swifts,” she writes a wonderful description of the small birds as created by a Great Raven:

“So the Raven took their legs and bound them into their bodies.

He bent their wings like boomerangs, honed them like knives.

He streamlined their feathers and stripped them of velvet.

Then he released them, Never to Return

Inscribed on their feet and wings.”

Like Stevenson’s above description, Chimney Swifts are one of the most aerial birds, flying at all times unless roosting overnight or nesting. They perform aerial courtship displays within 2 weeks of arriving on their North American breeding grounds, forming monogamous pairs for the season.

Often an unmated helper may assist a breeding pair with rearing the young. After the young fledge, small groups of parents and young from several chimneys join larger staging flocks in bigger chimneys nearby. At the end of summer they gather into large groups to migrate to South America.

Before the arrival of European colonists, Chimney Swifts nested and roosted in large hollow trees.  In 1682 the first swift was found nesting in a chimney at a colonist’s cabin in Maine. Over the centuries, Chimney Swift nesting sites switched almost entirely to chimneys. Naturalist John Burroughs describes in 1904 the “thunder of their wings at all hours of the day and night” heard when Chimney Swifts nested in his cabin chimney. Later Burroughs describes the site of watching “10,000” Chimney Swifts funneling into a large smoke stack near Boston:

“…filling the air above a whole square like a whirling swarm of huge black bees, but saluting the ear with a multitudinous chippering, instead of a humming… After a great many feints and playful approaches, the whirling ring of birds would suddenly grow denser above the chimney; then a stream of them, as if drawn down by some power of suction, would pour into the opening. For only a few seconds would this downward rush continue; then, as if the spirit of frolic had again got the upper hand of them, the ring would rise, and the chippering and circling go on. In a minute or two the same [maneuver] would be repeated, the chimney, as it were, taking its swallows at intervals to prevent choking. It usually took a half-hour or more for the birds all to disappear down its capacious throat.”

Due to the disuse of chimneys, ill-timed cleaning of chimneys and capping of chimneys, Chimney Swifts are in peril. Chimney Swift conservationists Georgean and Paul Kyle have written a book on how to help by building towers to compensate for the loss of habitable chimneys. The Kyles also created and currently steward the Chaetura Canyon sanctuary for Travis Audubon Society. It’s a special place well worth a visit.


Compiled and written by Lindsey Hernandez.

Sources include All About Birds, Texas Parks & Wildlife, and the Audubon Field Guide to North American Birds.