Grey-necked rockfowl

This species was first described by Anton Reichenow in 1899 from a bird collected at the base of Mount Cameroon near Limbe, Cameroon. The generic name was first used by René-Primevère Lesson in 1828 after he split the grey-necked rockfowl's close relative the white-necked rockfowl from the crow genus Corvus and placed it in its own genus, Picathartes, as the white-necked rockfowl did not share characteristics common to members of Corvus such as a feathered head. This generic name comes from a combination of the Latin genera pica for "magpie" and cathartes for "vulture". The species name is derived from the Ancient Greek word oreas, meaning "mountain". Since its initial description, the picathartes have been placed in more than five different families, including those of crows (Corvidae), starlings (Sturnidae), Old World flycatchers (Muscicapidae), babblers (Timaliidae) and Old World warblers (Sylviidae). Today the grey-necked rockfowl and the white-necked rockfowl are believed to comprise a unique family, Picathartidae. Additionally, it has been suggested, though not generally accepted, that the two rockfowl represent the remnants of an ancient bird order. The analysis suggests that the rockfowl split from the common ancestor of their clade 44 million years ago. Rockfowl is a reference to the species' habit of building mud nests on rock surfaces and caves. Picathartes refers to the species' scientific name. Bald crow is a reference to its featherless head and somewhat crow-like appearance, especially in its beak. ==Description==

This rockfowl measures approximately in length, with its notably long tail contributing about . This species does not show sexual dimorphism. There are some small, bristle-like feathers located on the crown that can be erected. Behind the crown, the species' bare skin on the hindcrown and nape is carmine in coloration and has a few more bristle-like feathers. The nestling is born nearly featherless except for tiny primary quills and a fine down along its spine, humerus, forearm, and femur. ==Distribution and habitat==

are a nesting area The grey-necked rockfowl is found in West Africa from southeast Nigeria to southwest Gabon. In Nigeria, it is only found in the nation's southeastern corner near the coast and the Cameroon border. The species is widespread in southwestern Cameroon, and this country is considered to be the species' stronghold. It is found throughout Equatorial Guinea and into southwestern Gabon. Additionally, the species resides in the southwestern forests of the island of Bioko in the Gulf of Guinea. There is only one record of this species from the Republic of the Congo, though it is suspected that the rockfowl may have an undiscovered population in this country. The grey-necked rockfowl's total range covers approximately . The grey-necked rockfowl prefers rugged terrain in these forests covered in large boulders, caves, and gorges. Additionally, it often found near inselbergs and a source of water, either a river or a forest pool. The understory of its forests has sparse undergrowth or open spaces but is covered in mosses, ferns, lianas, and epiphytes. In southwestern Bioko it is found in low forests that receive nearly of rain a year. Bioko's habitat also has dense undergrowth and vertical gorges near a caldera. The rockfowl's habitat is normally found between above sea level, though it is lower in elevation on Bioko. This species is non-migratory, and at one site in Cameroon the birds remained within of their nesting site throughout the year. It is capable of living near human activity, and one breeding site in Cameroon was located within of a maize plot. This and other recent observations suggest that the rockfowl has greater tolerance for degraded habitat than previously thought. ==Ecology and behavior==

This rockfowl usually lives either alone or in pairs, although small flocks of three to ten birds are not uncommon. However, if these birds know that they have been sighted, they can become quite inquisitive and occasionally approach observers. It bathes in small pools. It crushes snails with its beak and, if its prey struggles, smashes it against the ground. It is known to regurgitate what it has eaten in pellet form. Rove beetle larvae and ants were the most frequently eaten prey in a study in Nigeria. In Equatorial Guinea, nesting occurs in mid-February. The male and female rockfowl work equally on the nest's construction, and it can take two to three months to build one, though in some extreme cases it takes more than a year. After the mud dries, it becomes a very hard structure. In one case, a second pair of rockfowl moved onto a nest after killing the first pair's nestlings. ==Relationship with humans==

In Cameroon, the grey-necked rockfowl is respected by the indigenous peoples and, in some cases, even feared. Hunters sheltering in the rockfowl's nesting caves have been known to kill and eat adult rockfowl, though it is generally thought to be too small to eat and is left for children to hunt. British conservationist and author Gerald Durrell made this species a target on two of his trips to Cameroon, which he describes in The Bafut Beagles and A Zoo in My Luggage. It is considered one of the most difficult species of bird to see in the wild. Conservation The grey-necked rockfowl is considered to be vulnerable due to habitat destruction, its isolated populations, collection of adults, predation, and a low breeding success rate. Its habitat is being destroyed to create large agricultural fields and cocoa plantations, as well as for logging and slash-and-burn agriculture. Competition for its nesting sites is a result of these strict requirements and can lead to infanticide. Its estimated population is between 2,500 and 10,000 individuals, though it is believed that the population is at the lower end of the estimate. == References ==