Fork-tailed Swift vs Pallid Swift

Fork-tailed Swift

Apus pacificus

Small39 gWoodland

At 17–18 cm (6.7–7.1 in) in length, the Pacific swift is the largest of the Apus swifts. It has a 43-to-54-cm (17-to-21-in) wingspan. Females are slightly heavier than males, averaging 44.5 g (1.57 oz) against 42.5 g (1.50 oz). It is similar in general shape to the common swift, although slightly longer-winged and with a more protruding head. The fork of the tail is deeper, and the rump is broader. The upperparts are black, apart from a white rump band and a somewhat greyer head. Voice: The calls given by flocks near the breeding areas are typical swift screams, including a trilled tsiririri or harsher spee-eer. They resemble the cries of the common swift, but are softer and less wheezy. Pacific swifts are less vocal on the wintering grounds, but produce a variety of twitters and buzzes.

ID text from Wikipedia, CC BY-SA 4.0

Photo: ozma · CC BY 2.0

Pallid Swift

Apus pallidus

Small42 gRocky

This 16–17 cm (6.3–6.7 in) long species is very similar to the common swift, and separation is only possible with good views. Like its relative, it has a short forked tail and very long swept-back wings that resemble a crescent or a boomerang. It is entirely dark except for a large white throat patch which is frequently visible from a distance. It is chunkier and browner than common swift, and the slightly paler flight feathers, underparts and rump give more contrast than that species. It also has a scalier looking belly and subtly different flight action.

ID text from Wikipedia, CC BY-SA 4.0

Photo: Hobbyfotowiki · CC0

Photos and recordings are credited to their authors under the licence shown. Full profiles: Fork-tailed Swift and Pallid Swift.