Christmas Island Swiftlet vs Alpine Swift
Collocalia natalis so với Tachymarptis melba
Side-by-Side Comparison
| Thuộc Tính | Christmas Island Swiftlet | Alpine Swift |
|---|---|---|
| Tên Khoa Học | Collocalia natalis | Tachymarptis melba |
| Bộ | Caprimulgiformes | Caprimulgiformes |
| Họ | Apodidae | Apodidae |
| Tình Trạng Bảo Tồn | Not Evaluated | Least Concern |
| Chiều Dài | — | — |
| Chiều Dài Sải Cánh | — | 43,9 cm (17.3 in) |
| Khối Lượng | 4,75 g (0.17 oz) | 97,5 g (3.44 oz) |
| Chế Độ Ăn | Aerial plankton feeder taking tiny midges, fungus gnats, and ballooning spiders in rapid coursing flights. | Aerial insectivore taking small flying insects and spiders; may forage at great heights following thermal … |
| Số Trứng | 2 | 1-4 |
| 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
Alpine Swift
Rapid series of short, clipped whistles; bright, clean notes delivered in quick succession with occasional doubled phrase.
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.
Alpine Swift
Breeds from southern Europe and North Africa east through Central Asia and the Himalayas to India. Migratory; winters in sub-Saharan Africa.
Tình Trạng Bảo Tồn
Christmas Island Swiftlet
Alpine 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.
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
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.
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.