Pacific Swift vs Great Dusky Swift
Apus pacificus compared with Cypseloides senex
Side-by-Side Comparison
| Attribute | Pacific Swift | Great Dusky Swift |
|---|---|---|
| Scientific Name | Apus pacificus | Cypseloides senex |
| Order | Caprimulgiformes | Caprimulgiformes |
| Family | Apodidae | Apodidae |
| Conservation Status | Least Concern | Least Concern |
| Length | — | — |
| Wingspan | 34.6 cm (13.6 in) | 33.8 cm (13.3 in) |
| Weight | 41.516666666666666 g (1.46 oz) | 83.0 g (2.93 oz) |
| Diet | Feeds aerially on tiny insects and spiders, often following weather fronts where aerial plankton concentrates. | Feeds on aerial plankton of tiny insects and spiders; entire diet captured during non-stop aerial … |
| Clutch Size | 1-3 | 1-2 |
| Population Trend | — | — |
Habitat Comparison
Shared Habitats
Pacific Swift only
Great Dusky Swift only
None
Song & Call Comparison
Pacific Swift
Thin, reedy trill with nasal overtone; soft chattering notes delivered continuously during rapid low-level flight over fields.
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
Pacific Swift
Breeds from Siberia and Japan south to China and the Himalayas. Long-distance migrant wintering in Southeast Asia and Australia.
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
Pacific Swift
Great Dusky Swift
How to Tell Them Apart
Pacific Swift
Dark blackish-brown upperparts; distinctive white rump patch contrasting with dark back; white throat patch; underparts dark with pale brown barring; deeply forked tail; white rump distinguishes it from Common Swift …
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
Pacific Swift
A medium-sized swift (17-18 cm) found across eastern Asia from Siberia to Australia. Dark plumage with a white rump patch and deeply forked tail. Aerial insectivore. A long-distance migrant, breeding in Asia and wintering in Southeast Asia and Australasia.
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.