Home | Species Database | Species Accounts | Bibliography | Researchers | Related Sites | Login

Black-breasted Snake Eagle
Circaetus pectoralis

Status: Lower risk

Population Trend: Stable.

Other Names: Black-breasted Harrier-eagle, Black-breasted Harrier Eagle, Black-chested Harrier-eagle, Black-breasted Snake-eagle, Black-chested Snake Eagle.

Circaetus pectoralis
click to enlarge
Distribution: Afrotropical. DEMOCRATIC REPUBLIC OF THE CONGO, eastern SUDAN and ETHIOPIA south to northern SOUTH AFRICA. more....

Subspecies: Monotypic.

Taxonomy: Formerly considered to be a subspecies of Circaetus gallicus (Stresemann and Amadon 1979, Amadon and Bull 1988), but the current prevailing opinion is that it forms a superspecies with C. gallicus and C. beaudouini (Clark 1999). A study by Lerner and Mindell (2005), based on the molecular sequences of two mitochondrial genes and one nuclear entron, showed that the snake eagles of the genus Circaetus form a monophyletic group that is sister to the Old World vulture group, Aegypiinae, as was found earlier by Wink (1995). Wink and Sauer-Gürth (2004) found that this species, the Short-toed Eagle (C. gallicus), and the Bateleur form a clade. Brown (1955) mentioned a mixed pair of C. pectoralis and C. beaudouini nesting near Kisumu in western Kenya, and there is another report of a mixed pair of C. pectoralis and C. gallicusin Ethiopia (Brown 1974 fide Snow 1978).

Movements: Partial migrant (Bildstein 2006). Possibly sedentary in some areas, but seasonal movements have been reported from the highveld of the former Transvaal, where it is present only during the non-breeding period (Boshoff 1997), Zimbabwe, where there is an influx and communal roosting during the dry winter months (Steyn 1982), and Kenya, where breeding birds apparently midrate north to the plains of southern Sudan in the wet season, and probably also in West Africa (Borrow and Demey 2001). This species may breed in a locality one year, but not the next, and the extent of these movements is unpredictable and the reasons for them are not well understood. Brown et al. (1982) suggested that two populations (local breeders and visiting nonbreeders) may be involved. See Boshoff (1997) for a further discussion. more....

Habitat and Habits: Occurs in open country in savanna woodlands, dwarf shrublands, thornbush, and semi-desert, often near water, avoiding mountainous and forested areas. Usually found singly, but may roost communally in aggregations of up to 200 birds during the non-breeding period, probably making it unique among eagles in this regard. This species often occurs alongside a Brown Snake-eagle, and the two species may even perch on the same or adjacent pylons without apparent animosity (Tarboton 1990). more....

Food and Feeding Behavior: Hunts from a perch, on the wing, flying fairly low, or by hovering (probably the largest raptor to do so), parachuting slowly to the ground to capture prey. Feeds mostly on snakes and lizards, but also takes rodents, frogs, and insects (Tarboton 1990). This species is attracted to grassfires (Dowsett-Lemaire and Dowsett 2006). more....

Breeding: The nest is a small stick structure, which is well concealed in a clump of mistletoe, or other epiphytic vegetation in a fairly small tree. The clutch size is 1 egg, which is white and unmarked. The female performs the incubating, and the male brings prey to her. The incubation and nestlings periods are about 52 and 90 days, respectively (Tarboton 1990). more....

Conservation: Widespread, but its status varies from uncommon to locally common (Simmons 2005). Populations are larger within reserves than outside in southern Africa (Simmons op cit.). Causes of death of five recovered birds ringed in South Africa were drowning in sheer-walled reservoirs (2), shooting (1), electrocution (1), and collision with overhead powerlines (1) (Oatley et al. 1998). Categorized globally as a species of "Least Concern" by BirdLife International.

Population Estimates: Ferguson-Lees and Christie (2001) placed the global population (defined as the number of adults and immatures at the start of the breeding season) in the range of 10,001 to 100,000, or even more individuals, based on its wide distribution. BirdLife International (2009) did not make a population estimate. more....

Important References: 
Boshoff, A.F. 1997. Black-breasted Snake Eagle. Pp. 198-199 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.
Ferguson-Lees, J., and D.A. Christie. 2001. Raptors of the world. Houghton
  Mifflin, Boston, MA.
Kemp, A.C. 1994. Black-breasted Snake-eagle. Pp. 131-132 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.
Simmons, R.E. 2005. Black-chested Snake-Eagle Circaetus pectoralis. Pp.
  493-494 in P.A.R. Hockey, W.R.J. Dean, and P.G. Ryan (eds.),
  Roberts Birds of Southern Africa. 7th ed. Trustees of the John Voelcker Bird
  Book Fund, Cape Town, South Africa.
Steyn, P. 1982. Birds of prey of southern Africa: their identification and
  life histories. David Phillip, Cape Town, South Africa.

Sites of Interest:
Black-breasted Snake Eagle photos.

Middleton, Angus
Simmons, Rob
Steyn, Peter

Last modified: 6/1/2012

Recommended Citation: Global Raptor Information Network. 2022. Species account: Black-breasted Snake Eagle Circaetus pectoralis. Downloaded from http://www.globalraptors.org on 27 Jan. 2022

Home | Species Database | Species Accounts | Bibliography | Researchers | Related Sites | Login

Copyright © 1999-2012 The Peregrine Fund. All Rights Reserved.