Bare-legged Swiftlet vs White-collared Swift
Aerodramus nuditarsus compared with Streptoprocne zonaris
Side-by-Side Comparison
| Attribute | Bare-legged Swiftlet | White-collared Swift |
|---|---|---|
| Scientific Name | Aerodramus nuditarsus | Streptoprocne zonaris |
| Order | Caprimulgiformes | Caprimulgiformes |
| Family | Apodidae | Apodidae |
| Conservation Status | Least Concern | Least Concern |
| Length | — | — |
| Wingspan | 25.0 cm (9.8 in) | 42.5 cm (16.7 in) |
| Weight | 13.3 g (0.47 oz) | 106.45 g (3.75 oz) |
| Diet | Obligate aerial insectivore; catches minute flies, beetles, and aerial spiders while foraging near cave roosts. | Obligate aerial insectivore; gathers small flying insects, winged ants, and airborne spiders during flight. |
| Clutch Size | -- | 2 |
| Population Trend | — | — |
Habitat Comparison
Song & Call Comparison
Bare-legged Swiftlet
High thin twittering; 'tsit-tsit' over New Guinea lowlands; echolocation clicks in cave roosts; calls weakly in flight; colonial nester producing soft flock chattering
White-collared Swift
Loud, screaming 'shreee-shreee'; powerful screeching trill; calls from large flocks over mountains; very audible; one of the loudest Neotropical swifts; alarm a harsh rattle
Geographic Range & Migration
Bare-legged Swiftlet
Found in lowland New Guinea and adjacent islands. Resident in lowland rainforest and forest edge. Little-known Papuan endemic.
White-collared Swift
Found from Mexico south through Central America to South America east of the Andes, reaching Bolivia and southern Brazil. Often in large flocks.
Conservation Status
Bare-legged Swiftlet
White-collared Swift
How to Tell Them Apart
Bare-legged Swiftlet
Small; dark grey-brown upperparts; pale rump band; underparts whitish-grey; forked tail; bare unfeathered tarsi distinctive among swiftlets; New Guinea lowland cave-nesting species; bare legs visible at nest but rarely field-observable.
White-collared Swift
Large; glossy blue-black plumage with bold broad white collar encircling entire neck; collar clean and complete; underparts black; large slightly forked tail; among the most recognisable Neotropical swifts due to …
About These Birds
Bare-legged Swiftlet
A small swiftlet (10-11 cm) found in New Guinea, particularly in lowland and hill forests. Distinguished by its bare, featherless tarsi. Dark plumage. Aerial insectivore. Colonial cave nester. Uses echolocation for cave navigation. Limited published ecological data.
White-collared Swift
A very large swift (20-22 cm, wingspan 45-55 cm) with a bold white collar band, the largest New World swift. Found from Mexico to southern Brazil and the Caribbean. Aerial insectivore, foraging in large, noisy flocks over forests and cities. Nests behind waterfalls and in caves.