Great Dusky Swift vs Asian Palm Swift
Cypseloides senex compared with Cypsiurus balasiensis
Side-by-Side Comparison
| Attribute | Great Dusky Swift | Asian Palm Swift |
|---|---|---|
| Scientific Name | Cypseloides senex | Cypsiurus balasiensis |
| Order | Caprimulgiformes | Caprimulgiformes |
| Family | Apodidae | Apodidae |
| Conservation Status | Least Concern | Least Concern |
| Length | — | — |
| Wingspan | 33.8 cm (13.3 in) | 22.9 cm (9.0 in) |
| Weight | 83.0 g (2.93 oz) | 8.833333333333334 g (0.31 oz) |
| Diet | Feeds on aerial plankton of tiny insects and spiders; entire diet captured during non-stop aerial … | Feeds on aerial plankton of tiny insects and spiders; entire diet captured during non-stop aerial … |
| Clutch Size | 1-2 | 1-3 |
| 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
Asian Palm Swift
High, wavering whistle with slightly nasal quality; gently pulsed notes trembling upward, characteristic of evening flight calls.
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.
Asian Palm Swift
Found from India and Sri Lanka east through Southeast Asia to the Philippines and Indonesia. Common resident in open areas near palms.
Conservation Status
Great Dusky Swift
Asian Palm Swift
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 …
Asian Palm Swift
Very slender; pale greyish-brown overall; paler below; extremely long deeply forked tail; tiny for a swift; South and Southeast Asian palm-nesting species; uniform pale brownish-grey coloration similar to African relative …
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.
Asian Palm Swift
A slender swift (13 cm) widespread across South and Southeast Asia from India to the Philippines and Indonesia. Dark brown plumage with a deeply forked tail. Aerial insectivore, closely associated with palm trees, nesting on the underside of palm leaves. Abundant in tropical lowlands.