Vaux's Swift vs Great Dusky Swift
Chaetura vauxi compared with Cypseloides senex
Side-by-Side Comparison
| Attribute | Vaux's Swift | Great Dusky Swift |
|---|---|---|
| Scientific Name | Chaetura vauxi | Cypseloides senex |
| Order | Caprimulgiformes | Caprimulgiformes |
| Family | Apodidae | Apodidae |
| Conservation Status | Least Concern | Least Concern |
| Length | — | — |
| Wingspan | 22.3 cm (8.8 in) | 33.8 cm (13.3 in) |
| Weight | 18.033333333333335 g (0.64 oz) | 83.0 g (2.93 oz) |
| Diet | Exclusively aerial insectivore catching small flying insects and spiders drifting in aerial plankton at altitude. | Feeds on aerial plankton of tiny insects and spiders; entire diet captured during non-stop aerial … |
| Clutch Size | 1-7 | 1-2 |
| Population Trend | — | — |
Habitat Comparison
Song & Call Comparison
Vaux's Swift
Soft, high sibilant whisper followed by ticking notes; delicate trill barely audible beyond immediate roosting vicinity.
Great Dusky Swift
Loud, churring trill; harsher and louder than other Cypseloides; calls over Iguacu Falls and major Neotropical waterfalls; buzzy 'bzzzt-bzzzt' in aerial groups
Geographic Range & Migration
Vaux's Swift
Breeds in western North America from Alaska south to Central America. Migrates to winter in Venezuela and northwestern South America.
Great Dusky Swift
Found in eastern South America from Venezuela and the Guianas south to Bolivia and Paraguay. Resident near rocky cliffs and waterfalls.
Conservation Status
Vaux's Swift
Great Dusky Swift
How to Tell Them Apart
Vaux's Swift
Small; dark sooty-brown upperparts; pale grey rump slightly paler than back; underparts pale greyish-brown; short spiny tail; smaller and paler-bellied than Chimney Swift; Pacific coast North American species with subtly …
Great Dusky Swift
Very large; entirely dark sooty-brown with pale grey forehead and chin scaling; slightly paler underparts; broad wings; largest Cypseloides swift; South American waterfall specialist with dusky uniform plumage and imposing …
About These Birds
Vaux's Swift
A small swift (11-12 cm) found in western North America from Alaska to Central America. Dark grey-brown plumage similar to Chimney Swift but smaller. Spine-tipped tail. Aerial insectivore, nesting in hollow trees and chimneys. Partial migrant wintering in Central America.
Great Dusky Swift
A large swift (18-20 cm) of southeastern Brazil, eastern Paraguay, and northeastern Argentina. Dark sooty-brown plumage. Aerial insectivore, foraging over forested gorges and waterfalls. Nests in large colonies behind waterfalls. The largest member of the genus Cypseloides.