The pygmy falcon (Polihierax semitorquatus) or African pygmy falcon is a bird of prey native to eastern and southern Africa. It is the only species placed in the genus Polihierax. It is the smallest bird of prey on the African continent. Description Adult pygmy falcons are white below and on the face, grey above, and females having a chestnut back. There are white "eye spots" on the nape. Juveniles have a brown back, duller than adult females, with 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). Distribution and habitat The pygmy falcon inhabits dry bush. The subspecies P. s. castanonotus occurs from South 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. Behaviour and ecology Pygmy falcons show physiological traits that have adaptive value in a region affected by environmental variability associated with the El Niño Southern Oscillation cycle as well varying food source. They regulate their body temperature by thermal buffering provided by sociable weaver colonies and communal roosting by the falcons. This is important because this reduces the energy requirements for rest-phase thermoregulation by occupants. Food and feeding Pygmy falcons prey on reptiles and insects, but will occasionally prey on small birds as well as rodents. They hunt from a perch, swooping down on potential prey. However, Kalahari tree skinks have learned to eavesdrop on sociable weavers to warn of approaching pygmy falcons and run for cover. Breeding In Kenya, pygmy falcons 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