Christmas Island Swiftlet vs Great Dusky Swift
Collocalia natalis compared with Cypseloides senex
Side-by-Side Comparison
| Attribute | Christmas Island Swiftlet | Great Dusky Swift |
|---|---|---|
| Scientific Name | Collocalia natalis | Cypseloides senex |
| Order | Caprimulgiformes | Caprimulgiformes |
| Family | Apodidae | Apodidae |
| Conservation Status | Not Evaluated | Least Concern |
| Length | — | — |
| Wingspan | — | 33.8 cm (13.3 in) |
| Weight | 4.75 g (0.17 oz) | 83.0 g (2.93 oz) |
| Diet | Aerial plankton feeder taking tiny midges, fungus gnats, and ballooning spiders in rapid coursing flights. | Feeds on aerial plankton of tiny insects and spiders; entire diet captured during non-stop aerial … |
| Clutch Size | 2 | 1-2 |
| Population Trend | — | — |
Habitat Comparison
Song & Call Comparison
Christmas Island Swiftlet
Very high, thin twittering; 'chip' notes over Christmas Island forest; audible echolocation clicks in sea cave roosts; one of smallest swiftlets; barely audible to humans
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
Christmas Island Swiftlet
Endemic to Christmas Island in the eastern Indian Ocean. Resident in forested areas. Small population vulnerable to introduced predators.
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
Christmas Island Swiftlet
Great Dusky Swift
How to Tell Them Apart
Christmas Island Swiftlet
Tiny; dark brownish-black upperparts with minimal gloss; pale grey-buff rump band; greyish-white underparts; forked tail; Christmas Island endemic; differs from Cave Swiftlet in duller upperparts and restricted oceanic island range.
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
Christmas Island Swiftlet
A small swiftlet (12 cm) endemic to Christmas Island in the Indian Ocean. Dark plumage with a slightly forked tail. Aerial insectivore, foraging over the island's rainforest canopy. Colonial cave nester. Population estimated at 6,000-8,000 individuals. Classified as Vulnerable.
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.