Southern Ground-hornbill

*For the Abyssinian ground hornbill, click here*

## About

A male southern ground-hornbill carrying prey in it's bill.

The southern ground-hornbill ***(Bucorvis leadbeateri)*** or cafer is a large species of hornbill which occurs in much of east and central sub-Saharan Africa. Southern ground-hornbills have mostly black plumage with white or pale grey flight feathers. The face, area around the eyes and the front of the neck are characteristically bare and a bright red in colour. Female ground-hornbills have additionally greyish, dark violet or deep blue throats. On both sexes the fleshy parts of the face are bumpy and the neck in particular swells outward. The bill is long, slightly curved and a dark grey colour. It also comprises a casque, a characteristic feature of species in the suborder Buceroti. The hornbill has relatively stout legs and four digits on each foot, with three facing forward and one facing backward. Southern ground-hornbills are large birds that grow to a height/length of 1m (3.2ft) and can weigh up to 2.2-4.2kg (4.8-9.2lbs). Additionally, the ground-hornbill possesses a wingspan of 1.2-1.8m (3.9-5.9ft). Despite the species' appearance, the ground-hornbill is well-flighted.

## Diet

Southern ground-hornbills are carnivorous birds that consume a variety of terrestrial animal species including small mammals, amphibians and reptiles, though they have been known to mainly hunt and eat insects. In times of severe food unavailability, the ground-hornbill will feed on carrion. The large bill of the hornbill allows it to pick at carrion but also attack larger prey items in order to subdue them. Uniquely, ground-hornbills have been known to collect prey for safe keeping, ordering prey stores in lines. As apex predators, ground-hornbills are ecologically important species and

## Conservation Status

The southern ground-hornbill is threatened by a variety of factors, resulting in the species' vulnerable status assigned by the IUCN. The species is threatened by naturally occurring threats like forest fires and violent storms but is mostly put at risk by agricultural developments and land clearing. Livestock grazing as a direct result of agricultural expansion has also limited the species' range, particularly in Kenya, where only 10% of the country is still inhabited by the ground-hornbill. Poison lures placed for livestock predators have also caused deaths. In the past, cultural beliefs offered the species protection in Kenya however, recent generations have not upheld these beliefs and do not care for the protection of the species. Adversely, in South Africa and Zimbabwe, the species is still regarded as culturally important and is protected under these regards. In South Africa electrocution is more of a threat to the southern ground-hornbill, as powerlines have resulted in one casualty and step-down electrical transformers have caused multiple, due to the birds congregating around insect nests built on and around them. Southern ground-hornbills may also be threatened by Newcastle's Disease, a highly infectious avian virus that can cause mass casualties and increase mortality in population.

## Range and Population

The southern ground-hornbill occurs throughout east and central sub-Saharan Africa in a vast and widespread range stretching as north as Kenya and as far south as the southern coast of South Africa. They inhabit open arid environments such as savannas, grasslands and shrublands however, they have also been known to exist in inland wetlands, woodlands and forests, as long as the foliage cover in these areas is not too thick. They inhabit lusher areas when compared to the closely related Abyssinian ground-hornbill ***(bucorvis leadbeateri)***. Southern ground-hornbills can be found at altitudes of up to 4,250m (13,943.6ft) in mountainous regions however, they are most frequently found in lowland environments. the current global population of the species has not yet been quantified however, during 1992, the South African population was estimated at 1,400 mature individuals. Southern ground-hornbills throughout Africa have been regarded as being commonly sighted and abundant.

## Behaviour

The southern ground-hornbill is a social bird that is usually found in familial groups of 2-11 individuals. These groups or flocks establish a hierarchy based upon age and size, with the dominant breeding pair being appointed as group alphas. The other "worker" individuals will forage for the group and juveniles may also join the group whilst still inhabiting their original home range. A flock will establish their own range and workers will guard this territory, establishing its borders by producing loud chorus calls which can be heard by other bird species from up to 2km (1.2mi) away. The territory is comprised upwards of around 50-100km² (31-62mi²) of open grassland, savanna or woodland. In warmer regions, ground-hornbills have displayed heat-avoidance behaviours in temperatures above 26oC (78.8oF). They spend 70% of their time on the ground and spend this time slowly patrolling their territory and foraging. Southern ground-hornbills mate during late summer, though not yearly and a male will attract a female based on his large size and will not fight other males over a female. Very little courtship is displayed however, male hornbills will emit a deep booing call and will inflate their neck pouch during "courting". A nest is constructed from leaves by the male in or around trees and cliffs in large crevasses or cavities. Copulation occurs here and the male will protect the eggs from small egg-eating predators while the female incubates. Together with the male worker hornbills, the male will provide the incubating female with food while she can't hunt. As a monogamous species, the pair will both take care of the chicks by feeding and protecting them. Two eggs are typically laid and hatch after 37-43 days, before the chicks fledge at around 86 days of age. A 3-7 day resting period is taken between the laying of the first and second eggs and so one chick is typically weaker and younger than the other, resulting in only the survival of the first laid chick. It is said that a southern ground-hornbill pair will only produce one successful fledgling once every nine years however, a subpopulation in the Okavango River Delta in Botswana have been noted to breed more frequently with greater success. After approximately four weeks since the first chick hatches, the female will leave the nest, really on the self-sufficiency of the now fledgling. The parents will continue to provide for the juvenile until it reaches sexual maturity however, some hornbills remain dependent on their parents for up to nine years. At around three years of age, ground-hornbills reach sexual maturity, as indicated by the transition of the juvenile bare skin from warm grey to bright red and dark violet beneath the neck in males and females respectively.

### Relationship with Humans

Ground-hornbills are culturally valued as an important species and is believed to be not only an omen of death but a protector. It is said to ward off evil spirits, witchcraft and evil magic such as lightening spells. If an individual lands on the roof of a house, it is said that someone will die in that building. Due to this cultural importance, individuals are often sacrificed in ceremonies to summon drought relief. The remains of those sacrificed are often used for traditional medicinal purposes. A very specific issue which has arisen between humans and the species, in which southern ground-hornbills have ben known to accidently destroy window panes while fighting their own reflection. This has unfortunately caused the species a bad reputation in areas where this is common-place. Yet another specific issue is that ground-hornbills have been known to accidently step on active land-mines in areas of war and conflict.

## In Captivity

The southern ground-hornbill is housed in over 40 zoos and institutes across Eurasia and North America. Some notable zoos which house the species include the San Diego Zoo, the Beijing Zoo and the Berlin Zoo in the USA, China and Germany respectively.

## Sources

* IUCN Red List of Threatened Species - https://www.iucnredlist.org/species/22682638/92955067
* Southern Ground Hornbill | Wikipedia - https://en.wikipedia.org/wiki/Southern\_ground\_hornbill
* Southern Ground Hornbill | Animal Diversity Web, University of Michigan Museum of Zoology - https://animaldiversity.org/accounts/Bucorvus\_leadbeateri/
* Southern Ground Hornbill | SANBI - https://www.sanbi.org/animal-of-the-week/southern-ground-hornbill/
* African Ground Hornbill | ZOOINSTITUTES - https://zooinstitutes.com/animals/african-ground-hornbill-253/