Polihierax semitorquatus, the African pygmy falcon, is native to two separate regions of Africa: northeastern Africa including Sudan, Somalia, Ethiopia, Uganda, and Tanzania; and southwestern Africa including Namibia, Botswana, Angola, and Cape Province. This species is generally non-migratory. Polihierax semitorquatas shares its geographic range with the range of social weavers, Philetairus socius, in southern Africa, and white-headed buffalo weavers, Dinemellia dinemelli, in northern Africa.
Biogeographic Regions: ethiopian (Native )
African pygmy falcons have a white face, breast, and abdomen. Female members have darker, chestnut colored backs, where males have grey backs. White spots decorate the back of the neck and the tail feathers. Polihierax semitorquatas has brown eyes and light orange legs. The base of the beak is an orange color, and the beak itself is grey. When hatched, African pygmy falcons are white in color and their eyes are shut. The eyes will normally open in two or three days. Young have paler feet than their adult counterparts, with a reddish-brown back and neck. The breast, face, and abdomen of juveniles is white. Members of the species will mature in approximately one year.
Range mass: 54 to 76 g.
Average length: 20 cm.
Average wingspan: 37 cm.
Other Physical Features: endothermic ; homoiothermic; bilateral symmetry
Sexual Dimorphism: female more colorful
Catalog Number: USNM 177898
Collection: Smithsonian Institution, National Museum of Natural History, Department of Vertebrate Zoology, Division of Birds
Sex/Stage: Male; Adult
Preparation: Skin: Whole
Collector(s): A. Donaldson-Smith
Year Collected: 1894
Locality: Laga, Goulf, Ethiopia ?, Africa
African pygmy falcons inhabit dry, arid climates with sparse vegetation. These areas may receive as little as 100 mm/year of precipitation, or up to 600 mm/year (Brown, et. al, 1982). With the exception of a few non-breeding members, African pygmy falcons almost exclusively inhabit areas where social weavers (Philetairus socius, in the SW portion of its range) or white-headed buffalo weavers (Dinemellia dinemelli, in the NE portion of its range) reside.
Habitat Regions: tropical ; terrestrial
Terrestrial Biomes: desert or dune ; savanna or grassland ; scrub forest
Habitat and Ecology
African pygymy falcons are carnivorous, with a diet consisting of mostly insects and lizards. Smaller birds and certain rodents are also sometimes preyed on. Occasionally these falcons will prey on weavers (Ploceidae) or their hatchlings when inhabiting their nests. It is believed that insects alone are insufficient for the dietary needs of young pygmy falcons. Lizards, rodents, and birds are crucial for the survival of the young. The falcon catches its prey by swooping quickly from the branch of a tree.
Animal Foods: birds; mammals; reptiles; insects
Primary Diet: carnivore (Eats terrestrial vertebrates, Insectivore )
Polihierax semitorquatus, due to its use of weaver nests (Ploceidae), can be considered parasitic or symbiotic, depending on the location. In the southwestern portion of their range, African pygymy falcons may protect social weavers from predators such as snakes, while gaining a safe area to raise young. White-headed buffalo weavers, in the northeastern part of their range, are more powerful than African pygymy falcons and receive no benefits from their presence. African pygymy falcons can be considered parasitic to white-headed buffalo weavers and considered a "nest pirate". African pygymy falcons are major predators of insects and lizards and are a danger to smaller birds and rodents.
Ecosystem Impact: parasite
Species Used as Host:
- white-headed buffalo weavers (Dinemellia dinemelli)
- social weavers (Philetairus socius)
- white-browed sparrow weavers (Plocepasser mahali)
- glossy starlings (Lamprotornis nitens)
- social weavers (Philetairus socius)
- glossy starlings (Lamprotornis nitens)
- white-browed sparrow weavers (Plocepasser mahali)
Polihierax semitorquatus is rarely preyed on, as it is a fairly powerful predator itself. Occasionally immature African pygmy falcons will be attacked in their nests, but the aggression of the parents during breeding season normally prevents this.
Life History and Behavior
The main communication between members of this species are the songs sung during mating, which are used to attract potential mates. Some bodily communication is seen during the courtship ritual, as the female indicates her availability by crouching and raising her tail feathers. The movements made by the male during courtship can also be perceived as a form of communication. African pygmy falcons have a very keen sense of sight, common to most diurnal birds of prey.
African pygmy falcons rarely call outside of the mating season. There have been a few different songs observed, including a "thin, squeaky 'tsip-tsip';'kiki-kik' (last syllable accented), or 'twee-twee-twip' used by [the male] calling [the female] from the nest; a sharp ringing 'ki-ki-ki-ki-ki-ki-ki-ki' by young in threat; in copulation, purring 'kirrrrr-kirrrrr-kirrrrr'; negging chicks 'seee-seee-seee'" (Brown, et al., 1982). The calls are usually high in pitch and soft.
Communication Channels: visual ; acoustic
Perception Channels: visual ; tactile ; acoustic ; chemical
Little is known concerning the lifespan of African pygmy falcons, though it is likely similar to the six to eight (with a maximum of about twenty) year lifespan of other diurnal birds of prey.
African pygmy falcons rely on the social weavers (Philetairus socius) in the northeast part of their range and white-headed buffalo weavers (Dinemellia dinemelli) in the southwestern part of their range for nesting. Occasionally northeastern birds will occupy the nests of white-browed sparrow weavers (Plocepasser mahali) and glossy starlings (Lamprotornis nitens). Approximately one-quarter of all weaver nests in these areas are occupied by African pygmy falcons. Thus, this falcon is one of a few species of birds that are "obligate nest pirates" (also see South American troupials, Icterus icterus).
More is known of Polihierax semitorquatus breeding habits in the southern portion of their range, but birds in both areas engage in a relatively quiet display that includes bobbing of the head, wagging of the tail, and calling. The female will squat down and raise her tail feathers to indicate that she is prepared to mate. Polihierax semitorquatus is usually seasonally monogamous, but is occasionally polyandrous, and it is not uncommon for two or more males to attend the same nest. This behavior may be influenced by limited availability of suitable nesting sites.
Mating System: monogamous ; polyandrous ; cooperative breeder
Polihierax semitorquatus usually will breed once per year, but will sometimes produce two broods in a favorable year. Eggs are normally laid about three weeks after copulation. The female lays from two to four eggs which are incubated for 27 to 31 days. Females begin incubating with the first egg laid, so hatching is asynchronous. Since the young do not hatch at the same time, they may be different sizes. The young will leave their nests from 27 to 40 days after hatching. Polihierax semitorquatus is considered sexually mature at one year of age.
Breeding interval: African pygmy falcons breed up to twice per year.
Breeding season: African pygmy falcons breed from June to December in northeastern Africa and August to March in southwestern Africa.
Range eggs per season: 2 to 4.
Range time to hatching: 28 to 30 days.
Range fledging age: 27 to 40 days.
Average time to independence: 2 months.
Average age at sexual or reproductive maturity (female): 1 years.
Average age at sexual or reproductive maturity (male): 1 years.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization ; oviparous
At the beginning of the breeding season, two or more parents choose a nesting chamber and reside there together. After the eggs are laid, the parents share incubation, with the female incubating most of the time and the male incubating while the female feeds. The male will also bring the female food while she is incubating. After hatching the female will tend to the young and the male will hunt for the family. After 21 days, when the chicks have grown feathers, the female will resume hunting. The birds leave the nest at around 27 to 40 days, but may remain with the parents for up to two months, and sporadically return to the nest. Both parents are very aggressive near their nest and their young do not usually fall victim to predators.
Parental Investment: altricial ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Male, Female, Protecting: Male, Female); pre-weaning/fledging (Provisioning: Male, Female, Protecting: Male, Female); pre-independence (Provisioning: Male, Female, Protecting: Male, Female); post-independence association with parents
Molecular Biology and Genetics
Statistics of barcoding coverage: Polihierax semitorquatus
Public Records: 0
Specimens with Barcodes: 4
Species With Barcodes: 1
African pygmy falcons are common birds within their range, they are not considered threatened. Man made structures have increased the number of potential nesting sites for these animals. It is possible, however, that urbanization could someday threaten Polihierax semitorquatus with habitat loss.
US Migratory Bird Act: no special status
US Federal List: no special status
CITES: no special status
IUCN Red List of Threatened Species: least concern
IUCN Red List Assessment
Red List Category
Red List Criteria
Relevance to Humans and Ecosystems
There are no adverse effects of Polihierax semitorquatus on humans.
Polihierax semitorquatus rarely intersects with humans due to the harsh climate that it lives in. The only real advantages to humans are ornithological study and birdwatching.
Positive Impacts: research and education
The pygmy falcon, or African pygmy falcon (Polihierax semitorquatus), is a falcon that lives in eastern and southern Africa and is the smallest raptor on the continent. As a small falcon, only 19 to 20 cm long, it preys on insects, small reptiles, and small mammals.
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, 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.
Range, habitat, and population
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.
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 the latter alone, though they do occasionally catch and eat nestlings and even adults.
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 behaviour: defence, 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.
- BirdLife International (2012). "Polihierax semitorquatus". IUCN Red List of Threatened Species. Version 2013.2. International Union for Conservation of Nature. Retrieved 26 November 2013.
- 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. Retrieved 2007-07-26.
- Sinclair, Ian; Hockey, Phil; and Tarboton, Warwick (2002). Birds of Southern Africa. Princeton University Press. pp. 116, 132. ISBN 0-691-09682-1. Retrieved 2007-07-26.
- Covas, Rita; Huyser, Onno; and Doutrelant, Claire (2004). "Pygmy Falcon predation of nestlings of their obligate host, the Sociable Weaver". Ostrich 75 (4): 325–326. doi:10.2989/00306520409485463. ISSN 0030–6525.
- Spottiswoode, Claire; Herrmann, Eric; Rasa, O. Anne E.; and Sapsford, Colin W. (2004). "Co-operative breeding in the Pygmy Falcon Polihierax semitorquatus". Ostrich 75 (4): 322–324. doi:10.2989/00306520409485462. ISSN 0030-6525.