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Rockfowl (Picathartes)Rockfowl or bald crows (Picathartes) are the only members of the family Picathartidae. These large (33–38 cm long) passerines have crow-like black bills and a long neck, tail and legs. They weigh 200–250 g. The strong feet and grey legs are adapted to move with long bounds on the forest floor. The birds seldom use their long wings for long flights. Both specis have white breasts and bellies and grey and grey-black wings, backs and tails. They also have bald heads with brightly coloured and patterned skin. The grey-necked species has a grey neck; the white-necked species has a white neck..
Rockfowl occur in West and western Central Africa, in Guinea, Sierra Leone, Liberia, Ivory Coast, Ghana (White-necked Rockfowl), Nigeria, Cameroon, Equatorial Guinea, Gabon and the Republic of the Congo (Grey-necked Rockfowl). They live in lowland rainforest at up to 800 m, in rocky and hilly terrain on the slopes of hills and mountains. They need forest litter for foraging, a large enough area to contain army-ant swarms and rocks, cliffs or caves for nesting sites. They are non-migratory.
Rockfowl are generalised feeders, foraging on the ground and in trees. When foraging in damp, rocky areas on the ground, they move forward with hops and bounds, then pause to search for prey. They use the longish bill to turn over leaves and seize prey. They take beetles, termites, ants and other insects, millipedes, centipedes, earthworms and gastropods. They mostly take frogs and lizards to feed to their chicks. They forage in shallow flowing water for crabs. They follow swarms of ants to snatch prey fleeing the ants.
Rockfowl breed seasonally in wet seasons. Despite reports of cooperative breeding, rockfowl are probably exclusively monogamous, breeding in pairs. They may breed in colonies of up to seven pairs, but solitary breeders and smaller colonies of two pairs are more common. The cup-like nest is made of dried leaves, twigs and plant fibres set into dried mud and is attached to a cave roof or overhanging rock on a cliff. Two eggs are laid, 24 to 48 hours apart. Both parents incubate the eggs, each taking 12 hour shifts before being relieved by their partner. It takes around 20 days for the eggs to hatch. The hatchlings are altricial, being helpless and almost naked, with a few feathers on the crown and back. They take around 25 days to fledge.
Both species are listed as Vulnerable to extinction on the IUCN Red List.
Rockfowl have been grouped with babblers, flycatchers, starlings, crows and other birds before being placed in a family of their own. In 1952, Serle thought the genus resembled the Asian genus Eupetes while Sibley used egg-albumin protein similarity, determined by electrophoresis, to suggest it belonged to the Timaliidae. Storr Olson revived the idea that it was related to Eupetes in 1979. A molecular sequence based study suggests that it may be closely related to crows and placed at the boundary between the Passerida and Corvida.
The species are the white-necked Rockfowl (Picathartes gymnocephalus) and grey-necked Rockfowl (Picathartes oreas). A possible third species may exist in Uganda, near the Kasinga Channel, linking Lake Edward with Lake George.