Southern ground-hornbill

Bucorvus leadbeateri

Photo by Marco Valentini (Internet Bird Collection)

Common name:
southern ground-hornbill (en); calau-gigante (pt); bucorve du Sud (fr); cálao terrícola (es); kaffernhornrabe (de)

Taxonomy:
Order Coraciiformes
Family Bucerotidae

Range:
This species is found from Kenya and Tanzania, through southern D.R. Congo and Zambia and into Angola, Mozambique and eastern South Africa.

Size:
These birds are 90-102 cm long. The females are smaller and weigh 2,3-4,6 kg, while the larger males weigh 3,5-6,2 kg.

Habitat:
These birds are found in open woodlands and savannas, as well as nearby grasslands and scrublands, pastures and agricultural land. They are present from sea level up to an altitude of 3.000 m.

Diet:
They mainly feed on arthropods, but also snails, frogs and toads, and sometimes larger prey such as snakes, lizards, rats, hares, squirrels or tortoises. There are also known to eat fruits, seeds and occasionally carrion.

Breeding:
The southern ground-hornbill breeds in September-March. They are monogamous, social breeders, with a dominant pair that breeds and helpers. They nest in a large cavity, in a tree or cliff, where the female lays 2 white eggs. The eggs are incubated by the female for 40 days, while the other group members bring her food. Usually only 1 chick is raised, being fed by all the members of the group and fledging 85-86 days after hatching.

Conservation:
IUCN status - VU (Vulnerable)
This species has a very large breeding range is reported to be widespread and common but sparse. The population is projected to suffer a large decline of up to 50% in the next three generation, as a result of habitat loss through clearance for small-scale use, agriculture, and because of fires, and perhaps because of the actions of African elephants Loxodonta africana in Botswana and South Africa. Widespread livestock grazing has also lead to the erosion of suitable grasslands and there is also some persecution and accidental poisoning when they consume poisoned baits. In South Africa there are extensive conservation programs for this species, including re-introductions, supplementary feeding, multiple clutching, group supplementation and artificial nest-site provisioning.

Silvery-cheeked hornbill

Bycanistes brevis

(Photo from Wikipedia)

Common name:
silvery-cheeked hornbill (en); calau-de-crista (pt); calao à joues argent (fr); cálao cariplateado (es); silberwangenhorvogel (de)

Taxonomy:
Order Coraciiformes
Family Bucerotidae

Range:
This species is patchily distributed from northern Ethiopia, through Kenya and Tanzania and into central Mozambique and Zimbabwe.

Size:
These birds are 60-75 cm long and weigh 1-1,5 kg.

Habitat:
The silvery-cheeked hornbill is found in mountain and coastal tropical forests, in gallery forests and in dry savannas with tall trees. They are present from sea level up to an altitude of 2.600 m.

Diet:
They forage on the forest canopy, mainly eating the fruits and berries of various plants including Ficus, Syzygium, Dracaena, Newtonia, Khaya and Strychnos. They sometimes also eat flowers. They also hunt animals, namely lizards, young birds and eggs, fruit bats, insects, centipedes and spiders.

Breeding:
Silvery-cheeked hornbills are monogamous, solitary nesters. They breed in September-April, nesting in a natural cavity in a trunk or large branch of a tree, 7-25 m above the ground. The same cavity is often reused in multiple breeding seasons. There the female lays 1-2 white eggs, which she incubates alone for about 40 days while the male brings her food. the female remains in the nest with the chicks until fledging, while the male brings food. The chicks fledge 77-80 days after hatching.

Conservation:
IUCN status - LC (Least Concern)
This species has a large but patchy breeding range. Although the global population size has not been quantified, the silvery-cheeked hornbill is reported to be locally common. The population is suspected to be stable in the absence of evidence for any declines or substantial threats.

Trumpeter hornbill

Bycanistes bucinator

Photo by Marco Valentini (Internet Bird Collection)

Common name:
trumpeter hornbill (en); calau-trompeteiro (pt); calao trompette (fr); cálao trompetero (es); trompeterhornvogel (de)

Taxonomy:
Order Coraciiformes
Family Bucerotidae

Range:
This species is found in East Africa, from Kenya to eastern South Africa, and west, through southern D.R. Congo and Zambia, into Angola.

Size:
This medium-sized hornbill is 58-65 cm long and has a wingspan of 60-62 cm. They weigh 450-1.000 g.

Habitat:
The trumpeter hornbill is found in both moist and dry tropical forests, as well as in dry savannas, especially along watercourses. They are present from sea level up to an altitude of 2.200 m.

Diet:
They mainly feed on fruits such as Ficus, Trichilia, Ekebergia, Diospyros, Drypetes, Rauvolfia, Berchemia, Xanthocercis, Afzelia, Rhoicissus, Antidesma, Monanthotaxis, Pterocarpus, Stychnos, but also flowers, invertebrates like woodlice, millipedes, caterpillars, spiders and crabs, the eggs and nestlings of other birds and wasp nests.

Breeding:
Trumpeter hornbills breed in September-January. The nest in natural holes in trees, or sometimes in rocky crevices. After mating the female enters the nest and seals it with mud and faeces collected by the male, staying there until the chicks are ready to fledge. The female lays 2-5 white eggs, which she incubates alone for around 24 days while receiving food from the male. The chicks are fed by the female, from food collected by the male, and fledge 50 days after hatching.

Conservation:
IUCN status - LC (Least Concern)
This species has a very large breeding range and is reported to be thinly distributed across a wide range, but locally common. The population is suspected to be stable in the absence of evidence for any declines or substantial threats.