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Trigonoceps occipitalis
– Vulnerable
Taxonomy
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Kingdom:
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ANIMALIA
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Phylum:
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CHORDATA
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Class:
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AVES
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Order:
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FALCONIFORMES
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Family:
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ACCIPITRIDAE
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Scientific Name:
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Trigonoceps occipitalis
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Species Authority:
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(Burchell, 1824)
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Common Name/s:
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WHITE-HEADED VULTURE (Eng)
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Assessment Information
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Red List Category & Criteria:
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VU C2a(ii) ver 3.1 (2001)
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Year Assessed:
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2007
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Assessor/s:
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BirdLife International
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Evaluator/s:
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Bird, J., Butchart, S. (BirdLife International Red List Authority) & Ndang'ang'a, P.K. (BirdLife International - Africa)
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Justification:
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This species has a small population that constitutes a single metapopulation as there is presumed to be movement of individuals within its large range. It has been uplisted to Vulnerable because information from across its range indicates that numbers are in decline owing to a variety of threats.
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History:
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| 1988 | - | Lower Risk/least concern (BirdLife International 2004) |
| 1994 | - | Lower Risk/least concern (BirdLife International 2004) |
| 2000 | - | Lower Risk/least concern (BirdLife International 2000) |
| 2004 | - | Least Concern (BirdLife International 2004) |
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Geographic Range
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Range Description:
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Trigonoceps occipitalis has an extremely large range in sub-Saharan Africa (from Senegal, Gambia and Guinea-Bissau disjunctly east to Eritrea, Ethiopia and Somalia, and south to easternmost South Africa and Swaziland), where it is uncommon to locally common, but generally widespread outside forested regions3. It has declined rapidly in parts of West Africa since the early 1940s2,6, and in southern Africa is now largely confined to protected areas. An extrapolated estimate of the global population suggested there were 2,600-4,700 pairs (7,000-12,500 mature individuals)1.
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Range Map:
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 (click for detailed map)
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Countries:
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Native:
Angola; Benin; Botswana; Burkina Faso; Burundi; Cameroon; Central African Republic; Chad; Congo, The Democratic Republic of the; Côte d'Ivoire; Djibouti; Eritrea; Ethiopia; Gabon; Gambia; Ghana; Guinea; Guinea-Bissau; Kenya; Malawi; Mali; Mauritania; Mozambique; Namibia; Niger; Nigeria; Rwanda; Senegal; Somalia; South Africa; Sudan; Swaziland; Tanzania, United Republic of; Togo; Uganda; Zambia; Zimbabwe
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Population
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Population Trend:
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Habitat and Ecology
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Habitat and Ecology:
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It prefers mixed, dry woodland at low altitudes, avoiding semi-arid thornbelt areas1. It also occurs up to 4,000 m in Ethiopia, and perhaps 3,000 m in Kenya, and ranges across the thorny Acacia-dominated landscape of Botswana1. It generally avoids human habitation1. The species is thought to be a long-lived resident that maintains a territory10. It may generally fly lower than other vultures, and is often the first vulture species to arrive at carcasses1. While it is often found on the periphery of vulture congregations at large carcasses, it is also often found at small carcasses and is probably an occasional predator1,5. It nests and roosts in trees, most nests being in Acacia spp. or baobabs1. Clutch size is one, the egg being laid a couple of months after rains have finished and the dry season is underway1. Pairs that breed have a success rate of 65-75%, however, up to 61% of pairs do not attempt to breed each year1,10.
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System:
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Terrestrial; Freshwater; Marine
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List of Habitats:
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| 2.1 | Savanna - Dry |
| 3.5 | Shrubland - Subtropical/Tropical Dry |
| 4.5 | Grassland - Subtropical/Tropical Dry |
| 14.2 | Artificial/Terrestrial - Pastureland |
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Threats
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Threats:
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Reductions in populations of medium-sized mammals and wild ungulates, as well as habitat conversion throughout its range best explain current decline1,2,8. Additional threats are indirect poisoning8 at baits set to kill jackals in small-stock farming areas, although this species is less susceptible than other vultures owing to its broad diet. Exploitation for the international trade in raptors9 also poses a threat.
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List of Threats:
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| 3.5.3 | Harvesting (hunting/gathering) - Cultural/scientific/leisure activities - Regional/international trade (ongoing) |
| 4.1.2.3 | Accidental mortality - Bycatch - Terrestrial - Poisoning (ongoing) |
| 5.2 | Persecution - Other (ongoing) |
| 8.3 | Changes in native species dynamics - Prey/food base (ongoing) |
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Conservation Actions
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Conservation Actions:
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Conservation measures underway:
This species currently occurs throughout much of southern and East Africa's protected areas network5.
Conservation measures proposed:
Carry out co-ordinated surveys throughout the range of this species to clarify its population size and trends. Raise awareness about the impact of poisoning on this species7.
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List of Conservation Actions:
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| 2.2 | Communication and Education - Awareness (in place, needed) |
| 3.2 | Research actions - Population numbers and range (in place, needed) |
| 3.9 | Research actions - Trends/Monitoring (in place, needed) |
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Bibliography
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Bibliography:
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Bird Reference Citations. The numbers inserted in the text accounts above (usually in bold) refer to references. For further details on these references, click on the BirdLife International link above to go to the specific species account on the BirdLife web site. In some cases, particularly in the taxonomic notes, the references are cited using the author names. Details for these can be found on the BirdLife International web site at the following two places:
For References from A–L.
For References from M–Z. BirdLife International. 2000. Threatened Birds of the World. Lynx Edicions and BirdLife International, Barcelona, Spain and Cambridge, U.K. BirdLife International. 2004 Threatened Birds of the World 2004. CD-ROM. BirdLife International, Cambridge, U.K.
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