This is a medium-sized swift, measuring from 12 to 15 cm (4.7 to 5.9 in) long, with a wingspan of 27 to 30 cm (11 to 12 in) and a weight ranging from 17 to 30 g. The adult's plumage is a dark sooty olive above and grayish brown below, with a slightly paler rump and uppertail. Its upperparts are uniformly colored, showing a little contrast between back and rump. The iris is dark brown. The bird has slender, curved and long wings; the legs are short. It is also able to focus a single eye independently.

Habitat and Distribution

The Chimney Swift breeds in the eastern half of the United States. In winter it migrates to South America. It has been recorded as a vagrant in Anguilla, Barbados, Greenland, Jamaica, Portugal, the United Kingdom and the U.S. Virgin Islands. The bird occurs over open country, savanna, wooded slopes and humid forest.


They forage on the wing, catching flying insects such as various species of flies, ants, bees, wasps, aphids, scale insects. It also eats spiders drifting on their threads. It is a predator of pest species.


The nest of a Chimney Swift bird is a shallow bracket made of sticks, which the birds gather in flight, breaking them off trees and then glued together using saliva. The female typically lays 4 to 5 eggs, which are long and elliptical in shape, moderately glossy, smooth and white. Incubated by both parents, the eggs hatch after 19 days.

Calls and Songs

The Chimney Swift has a twittering call, consisting of a rapid series of hard, high-pitched chips. It sometimes gives single chips.