Rothschild's Swift vs Great Dusky Swift
Cypseloides rothschildi compared with Cypseloides senex
Side-by-Side Comparison
| Attribute | Rothschild's Swift | Great Dusky Swift |
|---|---|---|
| Scientific Name | Cypseloides rothschildi | Cypseloides senex |
| Order | Caprimulgiformes | Caprimulgiformes |
| Family | Apodidae | Apodidae |
| Conservation Status | Least Concern | Least Concern |
| Length | — | — |
| Wingspan | 30.6 cm (12.0 in) | 33.8 cm (13.3 in) |
| Weight | 43.0 g (1.52 oz) | 83.0 g (2.93 oz) |
| Diet | Aerial insectivore feeding on swarms of small flies, winged ants, and tiny beetles during sustained … | Feeds on aerial plankton of tiny insects and spiders; entire diet captured during non-stop aerial … |
| Clutch Size | -- | 1-2 |
| Population Trend | — | — |
Habitat Comparison
Song & Call Comparison
Rothschild's Swift
Thin, buzzy twittering in flight; soft 'tsee-tsee' contact notes; calls over Andean waterfalls; quiet and unobtrusive vocally; high-pitched but weak; rarely heard
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
Rothschild's Swift
Found in the Andes of northwestern Argentina and adjacent Bolivia at 1,500–3,000 m. Very poorly known; nests near waterfalls in humid forest.
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
Rothschild's Swift
Great Dusky Swift
How to Tell Them Apart
Rothschild's Swift
Blackish-brown overall with subtle pale scaling on throat and forehead; underparts slightly paler brownish; no contrasting white markings; robust-bodied Andean swift distinguished from Sooty Swift by faint pale throat scaling.
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
Rothschild's Swift
A medium-sized swift (15-16 cm) found in montane forests of northwestern Argentina and southern Bolivia at 1,000-3,000 m elevation. Dark sooty plumage. Aerial insectivore, foraging over forested valleys. Nests behind waterfalls. Uncommon and local; named after Walter Rothschild.
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.