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PLATE 69: SWIFTS
Alpine Swift Tachymarptis melba pm, wv
L: 21. W: 57. Shape and behaviour as Common and Pallid Swifts, but much larger with markedly
slower and deeper, scything wingbeats; white underparts broken by dark breast-band; vent and
undertail-coverts brown, as upperparts. Voice Loud, dry chattering trill unlike that of Common
Swift, trit-it-it-it-itititit-it-it-it, accelerating then decelerating, rising and falling. Habitat Mountain
ridges, steep rock faces, also sea cliffs. Nests, usually colonially, in natural crevices on cliff face,
occasionally in ancient building. Note Mainly summer visitor; passage hatched, rare SE Arabia;
winter records Iran, UAE (where vagrant), Yemen.
Common Swift Apus apus pm
L: 16. W: 45. Almost uniform sooty in fresh plumage, but brownish and more contrasting in worn
plumage and in eastern subspecies pekinensis (which migrates through Oman), though much
depends on light conditions. Whitish round throat-patch, but variable; lacks contrast above but
underparts show inner flight feathers clearly paler than body and wing-coverts. Easily confused
with Pallid Swift (which see). Wing moult of adult is entirely in winter quarters (unlike Pallid Swift).
Voice High-pitched ringing shreee, similar to Pallid Swift. Mostly silent on migration. Habitat Aerial;
congregates in areas with suitable nesting sites or abundant food. Nests in buildings, under eaves,
occasionally on cliffs. Note Migrant breeder; passage hatched.
Pallid Swift Apus pallidus PM, MB
L: 16. W: 44. Slightly bulkier than Common Swift but all brownish with broader, less tapering outer
wing and sometimes blunter wing-tips; tail-fork slightly shallower (adult) with less pointed tips. Often
difficult to separate from Common Swift but head looks broad and flat with larger, more triangular,
whitish throat-patch; forehead and lores paler, contrasting with dark eye-patch. Faint scaling
visible on underparts; upperparts show darker ‘saddle’, slightly contrasting with paler inner
flight feathers, head and rump. Underwing shows darker outer primaries than inner wing, much as in
Common Swift. Adults commence wing moult in breeding areas in summer/autumn, unlike Common
Swift, which often appears badly worn. Voice Similar to Common Swift, but deeper, hoarser (tinnier,
less ringing; individual notes less clear-cut) and slightly disyllabic, sree-er. Habitat Nests in historic
buildings, new towers, cliffs or craggy outcrops. Note Migrant breeder; passage hatched.
Forbes-Watson’s Swift Apus berliozi MB
L: 17. W: 46. Separation from Common and Pallid Swifts extremely difficult. Plumage blackish-brown
with distinct slightly pointed white chin and throat (rounded in Pallid Swift) and slight white
forehead. At close range narrow pale feather fringes just detectable on upperparts, belly and
undertail-coverts; upperwing can occasionally show an oily, greenish sheen on outer primaries,
secondaries and median coverts; the underwing has paler, almost translucent secondaries and
inner primaries. Flight similar to Common Swift; wingbeats perhaps slower, and with longer, sweeping
glides. In the hand, outermost (tenth) primary longest (ninth primary longest in Common Swift). From
Pallid Swift by less noticeable saddle, slightly darker plumage, oily sheen to feathers on wing, and
voice. Voice A dry screeching schweee or schweee-weee-eee, less rippling and not as high-pitched
as Common Swift. Habitat Mountains, sea cliffs, foothills and plains. Note Mainly summer visitor
to S Arabia; known passage/dispersal hatched, but much confusion due to difficulty of identification.
Pacific Swift Apus pacificus V
L: 18–19. Larger than Common Swift, with white rump, more deeply forked tail, longer wings, pale
scaling to underparts and slimmer build with attenuated (Arctic Skua-like) rear end. Also more
protruding head and larger white chin-patch. Voice Unlikely to be heard in region; coarser and
harsher than Common Swift, closer to that of Pallid Swift and dropping off at end. Habitat Open
country. Note Vagrant Oman, UAE. [Alt: Fork-tailed Swift]
Little Swift Apus affinis pm
L: 12. W: 34. Smallest swift in the region, distinctive stout silhouette with short, square-ended tail
(round when spread); prominent deep, white rump-band ‘wrapped-around’ onto rear flanks (some
white visible at all angles). At longer distance can recall house martin, but dark underparts and stiff
wingbeats separate. Somewhat fluttering flight, alternating with short glides. Voice Fast, high-
pitched, rippling trill dillillillillill, regularly rising and falling in pitch, much higher-pitched and faster
than Common Swift. Habitat Over grassland or near water, often with other swifts; also gorges,
towns and cities (nests colonially on ceiling of open building, under rock overhangs, cave roofs).
Note Passage hatched, but rare; vagrant Bahrain.