Friday 24 May
In the News: Amphibians in the U.S. declining at alarming rate

What’s the World’s Favourite Species?
Find out here.| Kingdom | Animalia |
| Phylum | Chordata |
| Class | Aves |
| Order | Falconiformes |
| Family | Accipitridae |
| Genus | Stephanoaetus (1) |
The crowned hawk-eagle (Stephanoaetus coronatus) is one of the largest and most powerful eagles in Africa (5) (6). A fairly colourful bird, the head, back and wings are black or dark brown, the breast is cream or reddish, with distinctive black mottling or barring, and there is a long crest on the head which can be raised and which gives the species its common name (2) (3) (5). The tail is long and boldly marked with three black bands (2) (3), and in flight the broad, rounded wings (2) (3) show a reddish underside, with white flight feathers that are clearly marked with three black bands in adult males and two in adult females (5) (7). The feet are large, yellow and very powerful, with formidable talons, and the legs bear barred, feathery “boots” right down to the ankles. The beak is also large and strong, with a conspicuous orange gape-flange (yellow in juveniles), but a dark grey cere. The eyes are a piercing pale yellow (3) (5). The female crowned hawk-eagle is larger than the male, and has heavier marking on the breast and a smaller crest (2) (3). The juvenile is distinct, being pale grey-brown above, with white scale-like edges to the feathers, a grey-brown tail, which has four dark bars in males and three in females, and a white head and underparts (3) (5). During its first few years, the juvenile crowned hawk-eagle gradually becomes darker and gains its black markings, but does not achieve full adult plumage until its fourth or even fifth year. Fledglings have grey eyes, which turn brown and then yellow as the bird matures (3) (7) (8).
The crowned hawk-eagle is quite a vocal bird (3) (5) (9), producing a penetrating and far-carrying keeoowee-keeoowee-keeoowee call during display flights (3) (5) (9). Females use a khoi-khoi-khoi call, often from the nest (5), as well as a shrill kwee-kwee-kwee when the male approaches with food, a call which is also used by the young (3).
The crowned hawk-eagle is a formidable predator, capable of killing prey up to several times its own weight (2) (3). Primates usually make up the bulk of the diet (6) (11) (12), though other mammals are also taken, including small antelopes, rodents, hyraxes and mongooses, as well as large lizards, birds such as hornbills, guineafowl and pigeons, and occasionally carrion (2) (3) (12). The crowned hawk-eagle typically hunts by dropping onto prey from a perch, though it may also snatch tree-dwelling prey in flight, or knock it to the ground (2) (3). The largest prey is dismembered on the ground and pieces may be cached in nearby trees and eaten over several days (2) (3) (5). Crowned hawk-eagle pairs sometimes hunt co-operatively and will share cached food (3).
Courtship in the crowned hawk-eagle involves a noisy aerial display in which the bird, usually the male, performs a series of undulating dives and upward swoops. On being joined by the female, the male may dive, upon which the female rolls and the pair may lock talons and cartwheel through the air (3). Nesting season varies with location (2) (3), and the nest is usually built in the main fork of a large tree, although it may rarely be built on a cliff when no large trees are available (13). A massive structure, it may measure up to two and a half metres across and three metres deep, and is built with sticks and lined with sprays of green leaves. The breeding pair may use the same nest for many years. One to two eggs are laid, and hatch after an incubation period of between 48 and 51 days. When two eggs hatch, the elder chick always kills its younger sibling within a few days, so that only one chick is raised (2) (3) (5). Fledging occurs after 90 to 125 days, but the young crowned hawk-eagle is dependent on the parent birds for up to another 350 days, meaning the crowned hawk-eagle is usually only capable of breeding every other year (2) (3) (14).
TopThe crowned hawk-eagle has a relatively patchy distribution across sub-Saharan Africa, from Senegal to Liberia, east to Sudan and Ethiopia, and south to Angola, Zambia, Zimbabwe, Mozambique and South Africa (2) (3) (10).
TopThe crowned hawk-eagle inhabits forest and dense woodland, including rainforest, riverine forest and montane forest, up to elevations of at least 3,000 metres (2) (3). It may also be found in plantations and in remnant forest patches, and may sometimes move into surrounding secondary forest or dry savanna to forage (2) (3) (5).
TopThe crowned hawk-eagle is classified as Near Threatened (NT) on the IUCN Red List (1) and listed on Appendix II of CITES (4).
TopThe crowned hawk-eagle has a large distribution and is not currently considered at high risk of extinction (10). However, its populations are thought to be in decline (10), and the species is under threat from deforestation and from overhunting of its prey, and is now rare in many parts of West Africa (2) (3). The crowned hawk-eagle also suffers persecution because of its size, reputation, and potential for taking small livestock, with birds being shot or trapped or the nests destroyed (2) (3). However, some foresters actually welcome this eagle and protect its nesting sites because it is considered beneficial for controlling mammals which may damage young trees (3).
TopInternational trade in crowned hawk-eagles should be carefully monitored and controlled under the Convention on International Trade in Endangered Species (CITES) (4), and the species is also listed under Class A of the African Convention on the Conservation of Nature and Natural Resources, meaning that a high level of authorisation is required before the crowned hawk-eagle can legally be killed or captured, and then only in restricted circumstances (15). The crowned hawk-eagle is found in a number of protected areas throughout its range, including Mount Kenya National Park in Kenya (16), Kibale National Park in Uganda (12), and Taï National Park, Ivory Coast (14) (17). Although not currently considered threatened in most areas, it is thought that the long-term future of the crowned hawk-eagle may increasingly rely on these forested reserves (3).
TopTo find out more about the crowned hawk-eagle see:
For more information on the conservation of eagles and other raptors, see:
For more information on this and other bird species please see:
Authenticated (24/05/10) by Dr Alan Kemp, retired Curator, Ditsong National Museum of Natural History (previously Transvaal Museum), and Research Associate, Percy FitzPatrick Institute of African Ornithology, University of Cape Town.
http://www.fitzpatrick.uct.ac.za/docs/alan.html
More »Related species
Image credit
© Michel Gunther / Biosphoto
Biosphoto
16 rue Velouterie
Avignon
84000
France
Tel: +33 (490) 162 042
Fax: +33 (663) 208 434
http://www.biosphoto.com/
Link to this photo
Embed this ARKive thumbnail link by copying and pasting the code below.
Terms of Use - The displayed thumbnail may be used as a link from your website to ARKive's online content for private, scientific, conservation or educational purposes only. It may NOT be used within Apps.
Read more about
MyARKive
MyARKive offers the scrapbook feature to signed-up members, allowing you to organize your favourite ARKive images and videos and share them with friends.
Terms and Conditions of Use of Materials
Copyright in this website and materials contained on this website (Material) belongs to Wildscreen or its licensors.
Visitors to this website (End Users) are entitled to:
End Users shall not copy or otherwise extract, alter or manipulate Material other than as permitted in these Terms and Conditions of Use of Materials.
Additional use of flagged material
Green flagged material 
Certain Material on this website (Licence 4 Material) displays a green flag next to the Material and is available for not-for-profit conservation or educational use. This material may be used by End Users, who are individuals or organisations that are in our opinion not-for-profit, for their not-for-profit conservation or not-for-profit educational purposes. Low resolution, watermarked images may be copied from this website by such End Users for such purposes. If you require high resolution or non-watermarked versions of the Material, please contact Wildscreen with details of your proposed use.
Creative commons material
Certain Material on this website has been licensed to Wildscreen under a Creative Commons Licence. These images are clearly marked with the Creative Commons buttons and may be used by End Users only in the way allowed by the specific Creative Commons Licence under which they have been submitted. Please see http://creativecommons.org for details.
Any other use
Please contact the copyright owners directly (copyright and contact details are shown for each media item) to negotiate terms and conditions for any use of Material other than those expressly permitted above. Please note that many of the contributors to ARKive are commercial operators and may request a fee for such use.
Save as permitted above, no person or organisation is permitted to incorporate any copyright material from this website into any other work or publication in any format (this includes but is not limited to: websites, Apps, CDs, DVDs, intranets, extranets, signage, digital communications or on printed materials for external or other distribution). Use of the Material for promotional, administrative or for-profit purposes is not permitted.