26/08/2021
The Southern Ground-Hornbill (Bucorvus leadbeateri) is the largest hornbill species in the world. It belongs to the family Bucorvidae, and it is one of two species within the genus Bucorvis. Another name in the genus, Bucorvus cafer, is a synonym of B. leadbeateri. They are the only hornbill species that does not seal the females in the nest during the breeding season. The Southern Ground-Hornbill is widely distributed, occurring in north Namibia and Angola, to northern South Africa and southern Zimbabwe through to Burundi and Kenya.
The species is well adapted for the terrestrial lifestyle; they have long stout legs, and they walk on the terminal joints of their short toes. The species moves around the landscape by walking slowly in a group formation. They spend about 70% of their day on the ground, foraging for food. As big is they are, like most birds, ground-hornbill can also fly.
The Southern Ground-hornbill has five different calls. They have a sharp, fast grunt that is usually used when the birds are playing, fighting or when in distress. Also, they have a begging call that is usually used by juvenile birds when they beg for food. Females also use the begging call during courtship feeding. They have an alarm call that is used to alert the group when there’s a predator present. Lastly they have a four note booming call, which is used as a territorial and long-range contact call.
Southern Ground-Hornbill exhibit cooperative breeding, living in groups of two to 11 individuals. The group is usually made up of a dominant breeding pair and mostly male helpers that assist the breeding pair in defending the territory, feeding and rearing chicks. Only the dominant male and females copulate. Breeding mostly takes place in natural caverns created in dead or live trees where females spend long periods of time before the egg laying process begins.
Nesting has been recorded to take place in the following tree species, Senegalia,, Adansonia, Brachystegia, Combretum, Diospyros, Ficus, Kigelia, Kirkia, Lannea, and Podocarpus, just to name a few. Southern Ground-Hornbill usually lay one to three eggs, but mostly two. The eggs are laid three to five days apart; by the time the second egg hatches its older sibling will outcompete the latecomer for food, and consequently only one chick is raised past the first couple of weeks.
During the mating season, the red pouch on the neck of males inflates. This pouch is used to make booming calls that are heard over long distances. The pouch is used to attract females for mating. The booming sound is usually mistaken for a lion’s roar.