- 4.3 in
- 11 in
- 0.5–0.8 oz
- Martinet de Vaux (French)
- Vencejo de Vaux (Spanish)
- Vaux's Swift is the smallest swift in North America.
- Vaux's Swifts roost communally, by the hundreds or sometimes the thousands, presumably to conserve heat. They let their body temperature drop and become torpid on cold nights, reviving in the warmth of day.
- Vaux's Swifts descend into their roost tree essentially at once, spiraling down in a very dramatic rush at nightfall.
- Vaux's Swift is named for William S. Vaux, a member of the Academy of Natural Sciences and a friend of John K. Townsend, who first described the species. The name is pronounced "vawks," not "voh."
Nests in coniferous or mixed forest. Forages in forest openings, especially above streams.
Flying insects and some spiders.
- Clutch Size
- 3–7 eggs
- Egg Description
- Condition at Hatching
- Naked and helpless.
Half-cup made of small twigs glued to vertical surface with the bird's sticky saliva. Nests communally, usually in hollow trees, less commonly in chimneys.
Forages in the air, taking insects in its bill.
Declining throughout range. Logging of large-diameter trees in old-growth forest eliminates nest sites.
- Bull, E. L and C. T. Collins. 1993. Vaux's Swift (Chaetura vauxi). In The Birds of North America, No. 77 (A. Poole and F. Gill, Eds.). Philadelphia: The Academy of Natural Sciences; Washington, D.C.: The American Ornithologists' Union.