Chimney Swifts catch insects in flight and cling to the inside walls of chimneys or tree cavities when they rest.
This small, slender gray bird has long, curved wings and makes shallow, rapid wingbeats.
It catches insects on the wing and often uses chimneys for nesting or nighttime roosts in North America. After breeding, it migrates to South America in flocks.
Both sexes snap off twigs with their feet in flight and carry them in the bill, forming a shallow half-saucer nest glued to a wall with saliva.
A clutch contains three to five pure white eggs, with incubation lasting 16–21 days; hatchlings are naked and helpless.
At about two weeks, the young outgrow the nest and cling to the nearby wall, sometimes before their eyes have opened.
An extinction-risk assessment has not been added yet.