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The only swift occurring regularly in the east. It once nested in hollow trees, but today it nearly always nests in chimneys or other structures. Because the bird can be easily captured and banded in such situations, it has been studied much more thoroughly than other North American swifts. In late summer, hundreds or even thousands of individuals may roost in one large chimney, gathering in spectacular flocks overhead near dusk.

The largest swift normally found in North America, uncommon and local in the far west. Where it occurs, it may be seen flying very high, gliding and wheeling gracefully in pursuit of flying insects. The Black Swift seems to be limited in range by its very particular choice of nesting sites: it requires shady, sheltered spots on vertical cliffs totally inaccessible to predators, and often nests on the damp rock behind waterfalls.

A small, dark aerialist of the west, often overlooked as it flight high over northwestern forests or low over lakes and rivers with stiff, rapid wingbeats. Similar to the well-known Chimney Swift of the east, but only occasionally nests in chimneys. Because of its reliance on large hollow trees for nest sites, it has become scarce as old-growth forest in the northwest has been destroyed.

Around rocky cliffs and canyon edges in the west, little groups of these elegant swifts go hurtling past the crags, calling in shrill voices. This species has been claimed to be one of our fastest flying birds, and any observer who has seen them pass at close range will believe it. White-throated Swifts are very wide-ranging, probably foraging in the air many miles from their nesting sites at times.

This big swift is common and widespread in the American tropics, where it is often seen in large, noisy flocks over any kind of terrain. Stray individuals have wandered north of the Mexican border on several occasions, appearing at various points along the Gulf Coast and at scattered other locations from California to Michigan and Ontario.