Description: The head, back, breast and wings of the rhinoceros hornbill are black; thighs and vent are white. The white tail has a broad black band. Feet are grayish-green. The large bill and casque are yellow and orange-red (black at the base in males); bill is slightly recurved with upturned casque atop the base of the bill. Eyes of the male are red with black rims. The natural color of the casque and bill is creamy white but they become cosmetically colored by rubbing them against a gland beneath the tail, which exudes an orangish- red oil. In addition to being smaller in size, female Rhinoceros hornbills have smaller casques with no black base and their red-rimmed eyes are white.
Size: Rhinoceros hornbills are very large birds. Males are between 37.5-41.5 inches (95-105 cm) long and 5.7-7.5 pounds (2.6-3.4 kg) in weight. Females weigh 4.5-5.1 pounds (2-2.3 kg).
Behavior: During non-breeding seasons, rhinoceros hornbills can be seen foraging in pairs or small flocks. Males often feed females, even during non-breeding seasons. They are fairly easy to locate due to their habits, size and sounds.
Diet: Rhinoceros hornbills mainly feed on fruits (preferably figs) but also eat arthropods, lizards, tree frogs, and bird eggs.
Communication: The large, bony, light-weight casque amplifies the honking squawk Rhinoceros hornbills use to communicate. This loud, harsh vocalization can often be heard between pairs and often have a sharper note used for flight take- offs. Rounded wings make flight more difficult and extremely noisy (“whooshing” wing-beats sound like an overloaded locomotive).
Reproduction: The female nests in natural cavities 30- 49 feet (9-15 m) up in tall trees. Together the pair “wall” the female in the nest with mud; the male leaves a small hole through which he uses his long beak to pass food to the female (and hatchlings). This protects the female and eggs from predators. One or two eggs are usually incubated 37-46 days. Chicks emerge after 39-51 days and fledge in 78-80 days. The female will molt during this time period in the nest.
Habitat/range: Rhinoceros hornbills live in extensive areas of primary evergreen and tall secondary forest (up to 4,593 feet or 1,400 m) in Thailand, Malaysia and Sumatra.
Status: Currently a CITES Appendix II species, and categorized as near threatened on the IUCN Red List. Reduction in numbers in many areas is due to the cutting of forests for agriculture and timber. It is also hunted for its bill and tail feathers, which are used in ceremonial dress, and is captured for trade and food.
