Great Dusky Swift vs Brown-backed Needletail
Cypseloides senex compared with Hirundapus giganteus
Side-by-Side Comparison
| Attribute | Great Dusky Swift | Brown-backed Needletail |
|---|---|---|
| Scientific Name | Cypseloides senex | Hirundapus giganteus |
| Order | Caprimulgiformes | Caprimulgiformes |
| Family | Apodidae | Apodidae |
| Conservation Status | Least Concern | Least Concern |
| Length | — | — |
| Wingspan | 33.8 cm (13.3 in) | 40.6 cm (16.0 in) |
| Weight | 83.0 g (2.93 oz) | 145.0 g (5.11 oz) |
| Diet | Feeds on aerial plankton of tiny insects and spiders; entire diet captured during non-stop aerial … | Aerial insectivore feeding on tiny flies, beetles, and ballooning spiders in rapid powerful aerial pursuit. |
| Clutch Size | 1-2 | 3-5 |
| Population Trend | — | — |
Habitat Comparison
Song & Call Comparison
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
Brown-backed Needletail
Rough, buzzy chatter with intermittent higher squeaks; coarse twittering delivered continuously throughout aerial foraging.
Geographic Range & Migration
Great Dusky Swift
Found in eastern South America from Venezuela and the Guianas south to Bolivia and Paraguay. Resident near rocky cliffs and waterfalls.
Brown-backed Needletail
Found from India and Sri Lanka through Southeast Asia to Borneo and the Philippines. Resident in lowland and hill forest, soaring over ridges.
Conservation Status
Great Dusky Swift
Brown-backed Needletail
How to Tell Them Apart
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 …
Brown-backed Needletail
Very large; dark brown upperparts with bronze gloss; no pale back saddle unlike congeners; white throat patch; white undertail coverts; short spiny tail; largest Hirundapus; brown rather than black overall …
About These Birds
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.
Brown-backed Needletail
A very large needletail swift (22-25 cm), the largest swift in Asia. Dark brown plumage with a paler brown back. Spine-tipped tail. Found in montane forests from India to Southeast Asia. Aerial insectivore with powerful flight. Often seen soaring over mountain ridges.