Polihierax semitorquatus, Photo: Michael Lahanas
Polihierax semitorquatus (A. Smith, 1836)
Report of the expedition for exploring central Africa p.44
The African Pygmy-falcon (Polihierax semitorquatus) is a falcon that lives in eastern and southern Africa, the smallest raptor of the continent. As a small falcon, only 19 to 20 cm long, it preys on insects, small reptiles and even small mammals.
Adult African Pygmy-falcons are white below and on the face, grey above, the female having a chestnut back. There are white "eye spots" on the nape. Juveniles have a brown back, duller than adult females, and a rufous wash on the breast. The flight feathers of the wings are spotted black and white (more black above, more white below); the tail is barred black and white.
The flight is low and undulating. In size, pattern, and the habit of perching upright on an exposed branch or treetop, this species resembles some shrikes.
The call is "a high-pitched kikiKIK, repeated" (Kenya) or "a 'chip-chip' and a 'kik-kik-kik-kik'" (southern Africa).
Range, habitat, and population
The African Pygmy-falcon inhabits dry bush. The subspecies P. s. castanonotus occurs from Sudan to Somalia and south to Uganda and Tanzania; P. s. semitorquatus occurs from Angola to northern South Africa. This range is estimated to have an area of 2.7 million km2, and the total population is estimated to be between 100,000 and 1 million birds.
In Kenya, African Pygmy-falcon nest in White-headed Buffalo-weaver nests, and the ranges of the two birds coincide. In southern Africa, they are found around Red-billed Buffalo-weaver nests but predominantly nest in the vacant rooms of Sociable Weaver nests, which are large and multichambered—even if the Sociable Weavers still have an active colony in the nest. Despite being bird-eaters and bigger than Sociable Weavers, the Pygmy-falcons largely leave the latter alone, though they do occasionally catch and eat nestlings and even adults.
African Pygmy-falcons occasionally engage in polyandrous relationships, where there are more than two adults living together and tending nestlings. There are four potential reasons for this behavior: defense, co-operative polyandry, delayed dispersal of offspring, and thermoregulation (warmth). Corroboration for the last is that in winter African Pygmy-falcons nest further inside the nest of Sociable Weavers, where there is better insulation.
1. ^ a b c d Zimmerman, Dale A.; Turner, Donald A.; and Pearson, David J. (1999). Birds of Kenya and Northern Tanzania. Princeton University Press. pp. 90–91, 110–111, 309. ISBN 0-691-01022-6. http://www.amazon.com/dp/0713663057. Retrieved 2007-07-26.
Source: Wikipedia, Wikispecies: All text is available under the terms of the GNU Free Documentation License