Swifts
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African Black Swift L: 18 cm (7") This is a dark, bulky, powerful, high-flying swift with a distinct white throat patch and contrasting greyish inner flight feathers (secondaries) . The very similar Common Swift (not illustrated) has a smaller throat patch and lacks a pale panel in the wing . The African Black Swift is resident near Pafuri (Lanner Gorge) and a fairly common winter (June– August) visitor elsewhere in Kruger, while Common Swift is a regular spring and summer (October–March) visitor to the park . African Black Swift has a high-pitched screaming “zzzzzzzzzZZZZTTT” call . Masters of the air, foraging birds can cover 1,000 km in a day, and often gather at termite emergences and fires to hawk insects . African Palm-Swift L: 18 cm (7") A slim grey-brown swift with a long, deeply forked tail, often held closed in a single spike . The flight is distinctive, being weak and erratic, low over the tallest trees . This is a common resident throughout Kruger, nesting and roosting in Borassus and Hyphaene palms . They drink and feed on the wing, and use their tiny legs with hook-like claws to cling to the underside of palm fronds . The nest is stuck to a palm frond using the birds’ glue-like saliva, and remarkably includes down feathers that have been dislodged from other birds in the air! For extra security, the eggs are also stuck to the nest . Little Swift L: 14 cm (5·5") Small, compact and direct-flying, this dark swift has a distinctive square white rump patch and a square tail – all other ‘white-rumped’ swifts having longer, forked tails . The flight action consists of regular bouts of flapping and soaring on stiff wings . This is an abundant resident in Kruger, nesting on a variety of man-made structures including many bridges . It is gregarious, gathering in large numbers near roost sites at dawn and dusk, and issuing shrill chittering calls . White-rumped Swift L: 15 cm (6") A small, dark, slender swift, with a narrow white crescent over the rump, and a forked tail with long, pointed sides . The flight action is elegant, fluid and effortless, with the tail often held closed forming a point . This is a common migrant (August–May) breeder to Kruger, with some birds overwintering . It is normally less common than Little Swift, and less gregarious, but will join mixed swift foraging flocks . The White-rumped Swift is an aggressive nest thief, often commandeering nests of swallows and Little Swifts by ejecting or smothering their chicks . It sometimes breeds co-operatively, with assistance from the previous year’s offspring . Swifts are fast-flying, scimitarwinged birds with minute feet that do not allow them to perch like swallows and martins (see pages 204–207). Swifts little swift 202 BIRDS OF THE AIR african black swift african palm-swift little swift white-rumped swift 203 ...


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