Chimney Swift

The Chimney Swift (Chaetura pelagica) is a medium-sized bird, cloaked in sooty gray plumage, with a body length ranging from 12 to 15 cm and a wingspan of 27 to 30 cm. It is characterized by its long, slender wings and very short legs, which render it incapable of perching like most birds. Instead, it clings vertically to surfaces. This bird is often seen in flight throughout the day, only coming to rest at night.

Identification Tips

Adult Chimney Swifts are dark sooty olive above and grayish brown below, with a paler throat and rump. Their wings are curved and long, extending beyond the tail when folded. The tail is short and square, with all ten feathers ending in sharp points that assist the bird in clinging to vertical surfaces. Both sexes are similar in appearance, with males being slightly heavier on average.

Habitat

Historically nesting in hollow trees, Chimney Swifts have adapted to urban environments, now favoring human-made structures such as chimneys for roosting and nesting.

Distribution

The Chimney Swift is a breeding visitor to the eastern half of the United States and southern parts of eastern Canada, migrating to South America for the winter. It is occasionally seen in the western U.S. and has been recorded as a vagrant in various locations, including parts of Europe and the Caribbean.

Behaviour

Chimney Swifts are highly social and rarely seen alone. They are superb aerialists, capable of drinking and bathing on the wing. They roost communally in large numbers outside of the breeding season and exhibit a distinctive wing-clapping behavior when disturbed.

Song & Calls

The Chimney Swift's vocalizations consist of a rapid series of high-pitched chirps and occasional single chirps.

Breeding

Chimney Swifts are monogamous and typically mate for life. They build nests of twigs and saliva on vertical surfaces, usually within chimneys. The female lays 4-5 white eggs, which are incubated by both parents. The altricial young hatch after 19 days and fledge a month later.

Similar Species

The Chimney Swift can be distinguished from the similar Vaux's Swift by its slightly larger size, longer wings and tail, and slower wingbeats. It is also darker on the breast and rump compared to Vaux's Swift.

Diet and Feeding

The diet consists primarily of flying insects and airborne spiders. Chimney Swifts are important predators of pest species and can consume thousands of insects per day while provisioning their young.

Conservation status

The Chimney Swift is currently classified as Vulnerable by the IUCN. Its population has experienced significant declines, possibly due to changes in the insect community from pesticide use. Conservation efforts include the protection of nesting sites and the construction of purpose-built towers to provide alternative roosting locations.