Bare-legged Swiftlet vs Alpine Swift
Aerodramus nuditarsus comparado com Tachymarptis melba
Side-by-Side Comparison
| Atributo | Bare-legged Swiftlet | Alpine Swift |
|---|---|---|
| Nome científico | Aerodramus nuditarsus | Tachymarptis melba |
| Ordem | Caprimulgiformes | Caprimulgiformes |
| Família | Apodidae | Apodidae |
| Estado de conservação | Least Concern | Least Concern |
| Comprimento | — | — |
| Envergadura | 25,0 cm (9.8 in) | 43,9 cm (17.3 in) |
| Peso | 13,3 g (0.47 oz) | 97,5 g (3.44 oz) |
| Dieta | Obligate aerial insectivore; catches minute flies, beetles, and aerial spiders while foraging near cave roosts. | Aerial insectivore taking small flying insects and spiders; may forage at great heights following thermal … |
| Tamanho da postura | -- | 1-4 |
| 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
Alpine Swift
Rapid series of short, clipped whistles; bright, clean notes delivered in quick succession with occasional doubled phrase.
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.
Alpine Swift
Breeds from southern Europe and North Africa east through Central Asia and the Himalayas to India. Migratory; winters in sub-Saharan Africa.
Estado de conservação
Bare-legged Swiftlet
Alpine 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.
Alpine Swift
Large; dark brown upperparts; white throat patch separated from white belly by dark brown breast band; brown flanks; bold tricoloured underpart pattern; one of Europe's largest swifts with distinctive white …
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.
Alpine Swift
A large swift (20-22 cm, wingspan 54-60 cm) with a white belly and throat contrasting with dark brown upperparts. Found from southern Europe and Africa to Central Asia. Aerial insectivore, foraging at great heights. Nests on cliff faces in large colonies. Powerful, fast flier.