Rufous-necked hornbill  (Aceros nipalensis)

Classified as Vulnerable (VU) on the IUCN Red List 2006 (1) and listed on Appendices I and II of the CITES (3).

Instantly recognisable as belonging to the hornbill family, the rufous-necked hornbill is very large with an impressive downwardly curved bill and block-like casque on top of the head and bill. Males have a rufous head and underparts with black back and wings, whereas females are dark brown to black all over. There is a ring of bare, blue skin around the red eyes and the bill is yellow with black and white barcode-like stripes. Both sexes call with a soft, barking kup (2) (4).

Found in Bhutan, Myanmar, China, Thailand, Laos, Vietnam and northeast India, the rufous-necked hornbill has suffered a huge population decline, and is thought to be extinct in its historical range country, Nepal (1).

This hornbill species is found in mature, dense, evergreen and broadleaved forest, mainly in the hills up to altitudes of 1,800 metres. It searches for large trees in which to nest (1) (2).

The life of a female rufous-necked hornbill is an extraordinary one, as she spends four months of every year incarcerated within a nest in a hollow tree. With help from her mate, she seals herself into the hole, between 6 and 33 metres above the ground, using semi-digested leaves, oil globules, and regurgitated mud. A slit-shaped entrance is left through which the male feeds the female and their chicks, and the female defecates, creating a large pile of guano at the base of the tree. The female lays about two eggs in April which she incubates through the dry season so that hatching is synchronised with the onset of the rainy season. After a total of 125 days of incarceration, the female breaks the nest’s seal and leaves, the chicks following shortly afterwards (2) (4).

Searching for fruit in the canopy, the rufous-necked hornbill is thought to prefer nutmegs, pears and figs, but will rely on whichever plant species are fruiting at the time. It is also known to eat crabs, beetles, cicadas, lizards, earthworms, frogs and birds, picking these from the leaf-litter and from the trunks and branches of large trees (1) (4).

As slow-growing, long-lived birds that have few offspring each year, rufous-necked hornbills are particularly susceptible to over-hunting and unfortunately it is a continuing threat to them. Hunting is most common in China, Thailand, Laos and Vietnam where the meat is said to be good to eat and the casque is often also sold, leading to the extreme rarity of the rufous-necked hornbill in all but the most remote areas (4).

The rufous-necked hornbill is also at risk from habitat loss due to its preference for very large living trees at nest sites. It is these trees that are first selected by commercial loggers for felling. The hornbill also requires very large areas of land for foraging and so fragmentation as a result of logging and road-building can quickly reduce the viability of a population (4).

Despite the inclusion of the rufous-necked hornbill in several wildlife laws, including protective acts in China, India, Bhutan, Myanmar and Thailand, it is persistently hunted. It has proved extremely difficult to protect the species through the law or through the use of rangers, but the governments of Laos and Vietnam are now tackling the problem through controlling gun ownership (4).

Habitat loss is also a wide-ranging problem with extensive underlying political and economic influences. The government of Bhutan has committed to ensuring 60% of the country remains covered by forest and that preservation of the environment takes precedence over economic benefits resulting from its exploitation (4).

The rufous-necked hornbill is present in low numbers in a large number of reserves, sanctuaries and national parks across its range, but the majority of these areas would benefit from improved management systems (4).

View information on this species at the UNEP World Conservation Monitoring Centre.

For further information on this species see

• BirdLife International. (2001) Threatened Birds of Asia: the BirdLife International Red Data Book. BirdLife International, Cambridge, UK.