The voice of Africa
There is perhaps not a more distinctive call in all of Africa than that of the African fish eagle Haliaeetus vocifer. Expressed in flight or perched, with the head thrown back, the evocative weeah-kyow-koy-koy-koy is a well-known sound in Africa. African fish eagles are found throughout most of Africa, having an Afrotropical distribution, and are one of the larger raptors. They are found in a wide variety of aquatic habitats, preferably those with calmer waters, although juveniles and immatures can be seen flying, roosting, and/or feeding as they make their way across drier regions in search of suitable territories. African fish eagles are distinct in their adult plumage with a white head, neck, mantle, breast, and tail, chestnut shoulders, belly, and thighs, and a black back and wings. Immature birds are less distinct with a mottled brown splashed with white plumage, often with a brown streak through the eye which can cause identification confusion. Adults are usually found in pairs, and usually establish a territory where they will stay, although they will become locally nomadic in response to drastic changes in food supply, as well as floods and droughts. They feed primarily on fish, but will also include birds, as well as mammals, reptiles, amphibians, and on occasion carrion in their diet. African fish eagles have a very distinctive fishing technique where they will drop to the water in a shallow plunge and at the last moment throw their feet forward to grab the fish. For the most part they do not submerge themselves in the water as the Western osprey does. However, while these birds can easily lift prey of 1.5kg, even fly with a 2kg prey item, prey items between 2-3 kg are dragged through the water to the nearest shoreline, and prey over 3kg is awkwardly splashed and hauled to the shoreline. To put this into perspective, these birds themselves only weigh between 2-3.6kg!
Written by: Minke Witteveen
For further reading:
- BirdLife International. 2016. Haliaeetus vocifer. The IUCN Red List of Threatened Species 2016. Accessed 2017-03-025. URL: http://www.iucnredlist.org/details/22695115/0.
- Christie, D.A. and Ferguson-Lees, J. Raptors of the World. . Pp. 394-396.