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Secretarybird
Sagittarius serpentarius

Status: Vulnerable

Population Trend: Declining.

Other Names: Secretary Bird.

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Sagittarius serpentarius
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Distribution: Afrotropical. SENEGAMBIA east to ETHIOPIA and SOMALIA and south to SOUTH AFRICA. more....

Subspecies: Monotypic. more....

Taxonomy: The taxonomic position of this monotypic family is still not resolved. Pycraft (1902) and Mayr and Amadon (1951) considered it to be closer to the Gruiformes than the Falconiformes. The DNA hybridization studies of Sibley and Ahlquist (1990) led them to suggest that the Secretarybird might be a sister group to the storks (Ciconiidae), and Wink and Sauer-Gürth (2004) came to the same tentative conclusion, based on their analysis of sequences of the mitochondrial cytochrome b gene. An earlier cytochrome b study by Seibold and Helbig (1995) tentatively found that Sagittarius is significantly closer genetically to the Falconidae than to the Accipitridae. Cytochrome b sequences analyzed by Sauer and Sauer-Gurth (2000) placed this species outside the Accipitridae, and it never appeared as a sister group to the storks; they were unable to shed light on its relationships. Still other taxonomists have suggested that the Secretarybird may be more closely related to the New World Cariamidae (screamers) than to the Falconiformes. Syringeal data analysed by Griffiths (1994) unequivocally grouped Sagittarius with accipitrid genera.

Movements: Generally resident, but somewhat nomadic, making local movements in response to fires, drought, and grazing. There are no regular seasonal movements in southern Africa, but wide fluctuations in numbers are known to occur at some localities (Tarboton and Allan 1984). In the Kalahari, large congregations may form at waterholes, and these birds must be drawn from a large area (Steyn 1982). In West Africa, this species occurs in the northern savannas only during the dry season (Borrow and Demey 2001). Steyn (1982) stated that young Secretarybirds remain within a few hundred meters of the nest during the first year or so, but four juveniles ringed in South Africa were recovered at distances ranging from 42 to 1,537 km from the ringing site in their first year (Oatley et al. 1998). more....

Habitat and Habits: A terrestrial predator of open country, mostly savannas, scrub, and grasslands with scattered small, thorn trees, and open patches in forests and woodlands. It is also attracted to man-made habitats, including airfields, pastures, and fallow fields. Avoids mountainous and hilly areas, as well as extremely arid areas (e.g., Namib Desert). Usually found walking on the ground in pairs, but sometimes occurs singly or in small family groups; larger concentrations occur at waterholes. Foraging can begin before dawn. Often soars on thermals at great heights (up to 3,000 m). Steyn (1982) estimated that a Secretarybird probably walks about 20-30 km/day before returning to roost in the late afternoon. This species often roosts in its nest in pairs year-round, or another flat-topped tree. more....

Food and Feeding Behavior: Steyn (1982) aptly commented that the diet is made up of virtually anything that a Secretarybird can find and kill. It stalks deliberately across open country searching for prey, including mammals up to the size of hares and hedgehogs, birds and their eggs, reptiles, including snakes, lizards, and small tortoises, amphibians, and various invertebrates, including insects, scorpions, millipedes, and crabs. Prey is usually caught in the bill, and it is swallowed whole. Larger prey are stamped to death before they are swallowed whole. These birds sometimes stomp the ground to flush prey. Although Secretarybirds are capable of killing and eating poisonous snakes, including puff adders and cobras, snakes represent only a small portion of the diet. Domestic fowl are taken in the vicinity of human habitations. Steyn (1982) reported that there is at least one instance of a bird swallowing a golf ball that was in play. more....

Breeding: Breeding can occur at any time of the year, but there is a peak of activity from July to January in more southern areas. The nest is a large platform of sticks lined with dry grass and placed on the top of a small, flat-topped tree, or even a bush only two meters tall, if no trees are available. Clutch size is 1-3 eggs. Eggs are unmarked and dull white in color. The incubation period is about 42 days, and the nestling period is variable, ranging from 10-14 weeks; thus, the breeding cycle requires about five months (Tarboton 1990). more....

Conservation: Widespread, but apparently declining in many portions of sub-Saharan Africa and now extirpated in some areas. Thiollay (2006) failed to record this species in West Africa, where there have been no reliable reports in 30 years, and he recommended that it be listed as globally Threatened. In all parts of its range, this species is negatively affected by the loss of habitat due to overgrazing, encroachment of human settlements, expanding agriculture, collisions with powerlines, and poisoning, but in other areas, the clearing of woodlands and bush for agriculture has created additional habitat. Previously categorized globally as a species of "Least Concern" by BirdLife International, it is now listed as "Vulnerable". more....

Important References: 
Boshoff, A.F., and D.G. Allan. 1997. Secretarybird. Pp. 152-153 in J.A.
  Harrison et al. (eds.), The atlas of South African birds. Volume 1:
  Non-passerines. BirdLife South Africa and Avian Demography
  Unit, Johannesburg, South Africa.
Brown, L.H., E.K. Urban, and K. Newman. 1982. The birds of Africa. Vol. 1.
  Academic Press, London.
Dean, W.J.R., and R.E. Simmons. 2005. Secretarybird Sagittarius
  serpentarius. Pp. 542-543 in P.A.R. Hockey, W.R.J. Dean, and P.G. Ryan
  (eds.), Roberts - Birds of southern Africa, VII edition. The Trustees of
  the John Voelcker Bird Book Fund, Cape Town, South Africa.
Ferguson-Lees, J., and D.A. Christie. 2001. Raptors of the world. Houghton
  Mifflin, Boston, MA.
Kemp, A.C. 1994. Secretarybird. P. 215 in del Hoyo, J., A. Elliott, and J.
  Sargatal (eds). Handbook of birds of the world. Vol. 2. New World vultures
  to guineafowl. Lynx Edicions, Barcelona, Spain.
Kemp, A.C. 1995. Aspects of the breeding biology and behaviour of the
  Secretarybird Sagittarius serpentarius near Pretoria, South Africa. Ostrich
  66:61-68.
Kemp, A., and M. Kemp. 1998. SASOL birds of prey of Africa and its
  islands. New Holland, London. 349 pp.
Steyn, P. 1983. Birds of prey of southern Africa. Tanager Books, Dover,
  NH.
more....

Sites of Interest:
VIREO
Secretarybird photos.

Researchers:
Obodi, Veryl Achieng
Runnels, Steve

Last modified: 5/10/2013

Recommended Citation: Global Raptor Information Network. 2017. Species account: Secretarybird Sagittarius serpentarius. Downloaded from http://www.globalraptors.org on 23 Oct. 2017








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