The rhinoceros hornbill (Buceros rhinoceros) is one of the largest hornbills, adults being approximately the size of a swan, 91–122 cm (36–48 in) long and weighing 2–3 kg (4.4–6.6 lb). In captivity it can live for up to 90 years. It is found in lowland and montane, tropical and subtropical climates and in mountain rain forests up to 1,400 metres altitude in Borneo, Sumatra, Java, the Malay Peninsula, Singapore, and southern Thailand.
The rhinoceros hornbill is the state bird of the Malaysian state of Sarawak and the country’s National Bird. Some Dayak people, especially the Ibanic groups, believe it to be the chief of worldly birds or the supreme worldly bird, and its statue is used to welcome the god of the augural birds, Sengalang Burong, to the feasts and celebrations of humankind. Contrary to some misunderstandings, the rhinoceros hornbill does not represent their war god, Sengalang Burong, who is represented in this world by the brahminy kite.
Like most other hornbills, the male has orange or red irises, and the female has whitish irises. This bird has a mainly white beak and casque, but there are orange places here and there. The tip of the casque curves markedly upward. The bird has white underparts, especially to the tail.
The courtship and bonding of these birds are critical, as the female must trust the male to provide her with everything when she is incubating and raising chicks. These hornbills make their nests inside tree trunks, and the female stays inside with the eggs and then with the chicks, while the male brings them food. After the eggs are laid, the male collects mud, and the pair pack that mud, along with food and feces, to wall up the entrance to the tree cavity. They leave a very small hole, just large enough for the male to feed the female, and later the chicks, and for the female to defecate through the hole. Once the chicks are fully feathered and old enough to leave the nest, the parents chip away the dry mud to let the chicks out.
The rhinoceros hornbill eats fruit, insects, small reptiles, rodents, and smaller birds.
The rhinoceros hornbill faces a number of threats, including loss of habitat and hunting for its meat, its feathers and its casque, which can be carved into ornaments and jewellery, and is as dense as ivory.