Bio Facts: Hornbill, Southern Ground
Leadbeater’s or Southern Ground Hornbill
Rwanda, Burundi, S. Kenya north to Eldoret and Turkwell Republic, SE Zaire, Tanzania (accidental to Zanzibar), Angola, Zambia, Malawi, N. Namibia, N. and E. Botswana, Zimbabwe, Mozambique, N. and E. South Africa in Transvaal, Natal and E. Cape Provinces.
African savannas south of the equator up to 9,800 feet. Leadbeater’s Ground Hornbills are common to woodlands, savannas and grasslands, avoiding forest of more continuous woodlands.
Body length – 2.9 to 3.25 feet. Adults have black plumage with white primary feathers. Bills are black with only a low ridge at the base. Bare skin around eyes and on throat are red. Eyes are yellow; legs and feet black. Females have a small patch of violet-blue on the throat that sometimes extends down the sides of the neck and small spots on the facial skin. Immatures are sooty-brown with flecks of black in the white primary feathers. Bills are smaller. Eyes are gray and facial skin is pale gray-brown. Sub-adults get adult colors by third year, but may not be fully mature until 4 to 6 years old.
Approximately 50 years
At 6 years of age
This is the only large ground hornbill that is almost entirely carnivorous. In the wild, they eat hares, tortoises, snakes and squirrels. In the Zoo, they are fed bird of prey mix, small bird mix, softbill diet, eggs, crickets, mice and chicks.
The Leadbeater’s Ground Hornbills are sedentary birds that live in cooperative breeding groups of 2 to 11 birds. These family groups are territorial. All members coordinate their activities and remain close throughout the day. There is one dominant pair that undertakes breeding. This pair forms a monogamous pair bond. Social organization is maintained by allo-preening and complex interactions involving the giving and withholding of food.
Ground Hornbills nest in large cavities such as the top of a broken off tree, rock faces, or earth banks near water. The same site may be used from 17 to 36 seasons. These sites, in turn, may be used by Barn Owls, or as retreats for monitor lizards, pythons, genets and leopards.
Two eggs are laid a few days apart. At hatching, each chick weighs approximately 2.1 ounces, is blind, naked and pink-skinned. By the time the second chick hatches, the older one will have quadrupled its weight and easily dominates in any competition for food. Usually only one chick is successfully raised. The family group will deliver 4-9 billfuls of food per day to the nest. Within three days the skin begins to turn dark purple while the throat and mouth lining remains pale pink. Eyes begin to open at 7 days. Although able to feed themselves by 6 months to 1 year, young may still be given food by group members when 2 years of age. Young remain with their parents for several years. Only 31% of fledged chicks in the wild survive to maturity. Leopards are their primary predators.
Leadbeater’s Ground Hornbills will eat any animal they can overpower up to the size of hares, squirrels, large tortoises and snakes. The group spends 70% of its day walking in search of food. They may cover 6 to 7 miles per day. In pursuit of large prey, the family group will band together for the hunt. Most food items are simply picked up from the ground or low vegetation sometimes after a short pursuit. Digging is prevalent during the dry season often in and around piles of elephant dung. Ground hornbills will also excavate wasp and bee nests and remove the comb and honey. They have been known to pursue large eagles for their prey and scavenge in or prey on their nests. Ground Hornbills often have their food pirated by Tawny Eagles. They will attend grass fires for prey flushed out by the flames.
Ground Hornbills fly over unsuitable habitat, to pursue an intruder in their territory or to reach their roosts at night. They can reach a flight speed of up to 18 mph.
If found lying flat on the ground with wings spread and sometimes being groomed by other group members, do not panic. This is how Ground Hornbills “sunbathe.”
Hornbills are the only birds with the first two neck vertebrae fused (axis and atlas). The large bill may be the reason for this phenomenon. Its long, downward curve that only allows the tips to meet properly forms a dexterous pair of forceps. Beak edges may also be serrated for cutting.
Communication: The main sound made by this bird is a deep, resonant 4 note booming or hoo hoo hoo-hoo. Uttered by all members usually just before first flight from roost, it has also been noted while walking or even flying. Usually this vocalization is heard at two different pitches – males usually lower than females higher pitched tone. But, either sex may call at either pitch when necessary to maintain duet. This sound may carry up to 3 miles away to human ears on a still day.
Other vocalizations noted include a harsh growl of threat, and alarm call of a single deep hu, a harsh nasal bray made by the female when accepting food and by begging juveniles, and soft peeping notes uttered by small chicks.
In the Hornbill family, there are 14 Genra and 45 species.
Leadbeater’s Ground Hornbills molt from November to June. A complete primary feather molt possibly extends over a three-year period.
Many Africans regard hornbills as sacred, so the large ground hornbills thrive virtually unmolested by man. Members of some West African Peoples (Hausa in particular) use the stuffed heads of ground hornbill as camouflage when hunting.
Populations are declining in areas of dense human populations and areas where suitable habitat has been destroyed. Leadbeater’s Ground Hornbills are persecuted in developed areas. Their aggressive territoriality leads to attacks on their own reflections in windows of these developed areas.
Jacksonville Zoo History:
This species first appears in the Zoo’s animal collection in November 1976. The Jacksonville Zoo first successfully hatched this species on May 29, 1981. This was the first successful North American breeding of this species. Until the 1990’s, all specimens hatched in North America were hatched here. To the best of our knowledge, the Jacksonville Zoo is the only zoo outside of southern Africa to exhibit this species in a family unit like they would typically be found in the wild.