the buttress root of a Piptadeniastrum tree above a small stream. Two nests were even built onto a concrete bridge in Gabon's Lopé National Park. 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. The nest itself is a half-cup constructed of dry mud with grass fibres and dead leaves mixed in, often with the plant matter sticking out of the nest's walls. It is either built onto the rock surface or, in some cases, is built more like a retaining wall across the opening of a small rock fissure. Nests are built at least away from each other, and in some cases up to . The nest is normally thick, though the nest is uneven in its construction and one nest was thick. It is about wide and long and weighs about . However, nest sizes do have a large degree of variability. After the mud dries, it becomes a very hard structure. The inside of the nest is lined with rootlets and thin strips of grass. One to three eggs, normally two, are laid, with the second egg being laid between 24 and 48 hours after the first. The eggs are variable in coloration and can be a light yellow-brown with dark brown blotches, creamy white with dark brown or grey blotches, or pale grey with brown mottling. The eggs weigh about and have an average size of by . The rockfowl begins to incubate after both eggs are laid. The time the rockfowl spends incubating varies greatly, though it is mostly for less than five minutes at a time with nearly two hours between sessions. Both the male and female rockfowl incubate. When the incubating bird's mate comes, it gives a brief call that causes the incubating bird to leave the nest. In the two days prior to hatching, the adult rockfowl prods at the eggs, sometimes with food in its beak. Incubation lasts for 21 to 24 days. When the infants hatch, they hatch about a day apart. The adult rockfowl quickly remove the eggshell fragments from the nest. The newborn weighs only after hatching, but it quickly gains weight. The eyes open and the tail begins to grow on the fifth day. During the first couple of days, food is brought