Trumpeter Hornbill

The trumpeter hornbill is a medium-sized hornbill, 58-65 cm long, with a large grey casque on the bill that is smaller in females. It has an all-black back, a white belly, white underwing coverts and red facial skin. It is a locally common resident of tropical evergreen forests in countries including Burundi, Mozambique, Botswana, Congo, Kenya, the Caprivi strip of Namibia and eastern South Africa, where it feeds on fruits and large insects. A gregarious bird, it usually lives in groups of two to five. As in other hornbills, the female incubates four to five white eggs while sealed inside the nest compartment.

About the trumpeter hornbill

The trumpeter hornbill is a medium-sized black-and-white hornbill that lives in the evergreen forests of eastern and southern Africa. It belongs to Bycanistes, a genus of mainly fruit-eating African hornbills, and to the hornbill family Bucerotidae, which also includes the ground hornbills and the Asian rhinoceros hornbill.

Adults measure 58–65 cm (23–26 in) from bill tip to tail and weigh between 0.45 and 1 kg (about 1 to 2.2 lb). The most obvious feature is the big gray casque, a hollow, horn-like structure that runs along the top of the bill. Males and females share the same plumage, but the female's casque is smaller. Across the hornbill family the casque varies a great deal. In some species it is barely noticeable and seems only to strengthen the bill, while in others it is large, braced with bone and open inside, so that it acts as a resonating chamber for calls.

The plumage is black on the back and white on the belly. The underwing coverts are also white, so in flight the wings show white tips. The eyes are brown or red and sit in patches of bare pink to red facial skin. All Bycanistes hornbills wear this black-and-white pattern, and the trumpeter can be confused with its larger relative, the silvery-cheeked hornbill.

Like other hornbills, the trumpeter has a heavy, down-curved bill held up by powerful neck muscles. Hornbills are the only birds whose first two neck vertebrae are fused together, which probably gives the bill a steadier base. The bill is used for fighting, preening, nest building and catching prey. Hornbills also have binocular vision in which the bill tip is visible to the bird itself, helping it handle food with precision, and long eyelashes that shade the eyes.

Bycanistes hornbills were often lumped into the related genus Ceratogymna, but most authorities now keep them separate. Genetic studies suggest Bycanistes is the sister group to the ground hornbills, and that the two split from the rest of the hornbill family early on, as an old African branch of a family that otherwise evolved in Asia. For more on the family as a whole, see the hornbill overview.

Hornbills are often mistaken for toucans, since both have huge bills. The likeness is convergent evolution: toucans fill the same niche in the American tropics but are related to barbets, while hornbills are closer to hoopoes and wood-hoopoes.

Behavior and diet

The trumpeter hornbill is a sociable bird. It usually lives in groups of two to five, but flocks can reach as many as 50. Like hornbills in general, it is diurnal, active by day. Outside the breeding season hornbills often gather in larger flocks, and some roosting sites draw huge numbers of birds.

What trumpeter hornbills eat

It feeds on fruit and on large insects. Bycanistes hornbills are primarily fruit eaters, and fruit-eating hornbills tend to live in forests, where they are considered important seed dispersers. Hornbills can't swallow food caught at the bill tip using the tongue, which is too short, so they toss each item back into the throat with a flick of the head.

In captivity, a diet heavy in fruit needs care, because trumpeter hornbills are prone to storing too much iron, a condition similar to hemochromatosis in people. Captive birds are active and intelligent and need plenty of room to move.

A nest sealed with mud

Like other hornbills, the female trumpeter hornbill incubates her four to five white eggs while sealed inside the nest. The details of how the seal is made are described for the hornbill family as a whole rather than for this species.

Hornbills nest in natural cavities, usually in trees. In every hornbill except the ground hornbills, the female, sometimes helped by the male, closes the entrance with mud, droppings and fruit pulp until only a narrow slit is left, just wide enough for the male to pass food through. The wall seems to protect the nest from rival hornbills, and sealing takes a few hours or at most a few days. While sealed in, hornbill females go through a complete molt, shedding their feathers all at once. When the chicks and mother outgrow the space, she breaks out, and both parents feed the young. In some species the chicks rebuild the wall themselves after she leaves.

Range and habitat

The trumpeter hornbill is a locally common resident of tropical evergreen forest in eastern and southern Africa. Its range includes Burundi, Kenya, Tanzania (including the North Pare Mountains), the Congo, Mozambique, Botswana, the Caprivi Strip of Namibia and eastern South Africa. It doesn't migrate, staying in the same area year-round.

Of the 24 hornbill species in Africa, 13 use open woodland and savanna and the remaining 11 live in dense forest. The trumpeter is one of the forest group, unlike the ground hornbills, the sister group of its genus, such as the southern ground hornbill, which walk the open savanna.

Trumpeter hornbill vs silvery-cheeked hornbill

The silvery-cheeked hornbill (Bycanistes brevis) is a close relative that shares East African evergreen forest with the trumpeter. Both are black and white with large casques, so field marks matter.

Conservation status

The trumpeter hornbill is listed as Least Concern on the IUCN Red List, most recently assessed in 2018. It is widespread across a large range and locally common.

That fits the wider pattern for its family. None of Africa's hornbill species are seriously threatened, while many Asian hornbills, especially island species, are endangered by hunting and by loss of the primary forest they need.