AFRICAN GRAY HORNBILL

Common Names: Gray hornbill, hornbill.

Order: Coraciiformes (“raven-shaped”)

Family: Bucerotidae

Latin Name: Tockus nasutus

Habitat and Range: Gray hornbills are found in Africa, primarily south of the Sahara, in a range (band) that stretches from coast to coast and into Arabia. An occupant of savannas (tropical or subtropical grasslands containing scattered trees and drought-resistant undergrowth), this bird may be seen in pairs or small parties, moving from tree to tree or feeding upon the ground.

Description: Adult male—dun-colored with a central light stripe from hind neck to rump; head, throat, neck more or less gray with a broad white stripe over eye to nape; wing feathers and coverts (feathers covering the bases of the quills of the wings and tail) edged with whitish; outer tail feathers tipped white; underside creamy white; bill black with a splash of cream at base of upper mandible. Female—smaller, bill is colored red at tip, and greater part of the upper mandible is yellow. Perhaps the hornbill’s most distinguishing characteristic is its large, long, downward curving bill which gives the bird a rather ungainly appearance.

Adult Size: About 18 inches with males being larger than females.The wingspread of the grey hornbill is 7.4 to 9.8”. .

Diet in the Wild: Various fruits and corn; reptiles and insects; they are attracted to grass fires and will travel great distances to reach them.

Reproduction: Two to four dull white eggs laid at considerable intervals in any suitable hollow in a tree. Male feeds female and the chicks so long as they remain inside. Incubation for hornbills in general requires 25-40 days depending upon the size of the species; nesting period 45-86 days depending upon the size of the species. Sexual maturity is reached at one year of age in the grey hornbill; at six years in some species.

Life Span: Unknown.

Perils: Probably birds of prey, some carnivores, man, habitat destruction.

Protection: Females and young wall themselves inside the nest (see “Facts”).

Interesting Facts: Hornbills have huge, two-tiered beaks that cause the birds to appear top-heavy. The bill is long forming dexterous forceps. The cutting edges are serrated for breaking up food. The casque surmounting the bill is a narrow ridge that may reinforce the upper mandible. In spite of its heavy appearance, the structure is a light skin of keratin overlying a bony support. The beak itself is honeycombed with air chambers, making it as light as a sponge. The casque possibly serves as a means of visual recognition but may be used in amplifying calls, in fighting, or to

7/07 knock down fruit. The large bill may explain why hornbills have the first two neck vertebrae fused together. Nesting African grey hornbills are monogamous, and their nesting habits are unique. Natural cavities are used. The female seals herself inside the nest, leaving only a narrow vertical slit through which the male will feed her and the young and through which she will forcibly expel droppings. At first she uses mud (while working from the outside) and later her own droppings mixed with food remains and feathers. In some species the male assists by bringing lumps of mud or sticky foods. The female undergoes a molt of all her flight and tail feathers at the time of egg laying. These are re-grown by the time she emerges from the nest. The incubation period is quite lengthy, and the young mature slowly. Her mate brings her food as often as 10-20 times a day.

When the chicks are about half grown, the female breaks out of the nest and helps the male to feed the nestlings. The nestlings need an insect each, every 10 minutes. The male needs help from his mate to provide sufficient food for their brood. In order to protect themselves from predators, as soon as the female leaves, young grey hornbills once again seal up the nest, breaking their way out only when they are ready to fledge.

These birds are sometimes called :Fire birds”, because when the fires sweep across the plains, the insects rise into the air attracting these birds from miles away to attend the feast.

Folklore: Many Africans consider hornbills to be sacred birds.

Ecology: Currently they are not endangered in the wild. They do no harm to people and are sometimes revered.

Diet at the Zoo: Grapes, nutrablend gold, bird-of-prey diet, mealworms.

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