THICK-BILLED RAVEN
(Corvus crassirostris)
Wing 427-472 mm
The Thick-billed Raven, closely related to the White-necked Raven (Corvus albicollis) of East and South Africa, is a bird which is common to abundant from about 1200 to at least 4100 meters (4000 .13,500 feet). It visits many habitats including alpine screes, Cliffs and gorges, giant lobelia-chemilla-tussock grass-glant heath moorlands, highland grasslands, giant lieath, St. John's wort, bamboo, juniper, podocarpus, olive and lowland subtropical humid forests.
It is especially abundant at higher elevations where it is obvious and sometimes bold around camps, villages and cities including Addis Ababa.
It is a frequent and persistent visitor to camps of travelers, where it scavenges for scraps including those in ashes of camp fires. This raven accompanies Lammergeiers (Gypaettus barbatus) when they drop bones and will steal from them if given a chance. Ravens sometimes also kill small rodents out on the open moorlands and grasslands and, by holding the huge arched bill up-side-down scatter dung to obtain insects. They feed on grain where "whole corners of the field (have) been cleared by them."
The Thick-billed Raven is easily recognized by the large curved, white-tipped bill and the white nape at the top of the neck. In flight, its neck extends forward, giving the raven a somewhat hornbill-like appearance. They are excellent fliers and soarers, often performing in formation along sheer cliff-faces. Two birds may give magnificent aerial displays, occasionally clenching feet and descending together for some 200 meters or so.
They nest in December, January and February on rocks and high up in trees. Details of the nest are unknown, as are the eggs. Although they usually live in pairs and are territorial, they sometimes congregate in parties of four to ten individuals. During courtship, the male feeds the female. He finds a morsel of food, then flies with it to a branch where he sits and calls his partner. She comes to him and flutters her wings, after which he feeds her. During this ceremony, the two birds produce hoarse gurgling and choking noises. Their typical call note, however, is a throaty "phlurk-phlurk" which has been described also as harsh and guttural or as a croak, which sounds as if the bird had "lost its voice" and was suffering from a "sore throat".
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