Rhinoceros Hornbill

By Rani Iyer

Scientific Name: Buceros rhinoceros

Deep in the rainforest of Borneo, high up in the canopy, lives a giant who is seldom seem. If you are careful, you can hear the giant woosh, woosh, woosh of flapping wings. Have no fear, this is a gentle giant.

The Rhinoceros hornbill is one of the largest birds in rainforests of Asia. They spend their entire lives on treetops. You might get giddy living up on a 70 m Dipterocarpus tree, but it is home for the rhinoceros hornbill. To nest however, they look for old or dead trees with cavity. To find food, they fly between fruiting trees occasionally stopping to grab small animals, like squirrels, in between. Can you imagine what logging will do to these birds?

At first glance, both male and female hornbills look alike. They have large wing span--- with white feathers for their tail. Their gleaming black feathers are maintained by spreading the orange colored preening oil all over their body. Hornbills can grow to be about 127 cm (50 in) long and weigh about 3 kg (about 6.6 lbs). But, look closer around the eyes and you will see the difference. The male birds have an orange or red ring around their eyes, while the ring remains white in female.

Rhinoceros Hornbill. Photo by Rhett A. Butler
Their beak is a marvel of nature. Lightweight and versatile, the beak can perform variety of jobs such as harvesting food, building the nest, sealing the nest, and feeding the chicks. On top of the beak is a casque, a hollow helmet-like structure, which helps to amplify their calls. Now you know how it gets its name. You can distinguish the deep, forceful hok, hok notes of the male from the female’s hak, hak notes. Sometimes, they have a duet. Usually, they call only when they defend their territories from other breeding pairs.

Rhinoceros hornbill usually pair for life. The couples choose a tree hollow or cavity and begin to build a nest. We never know how they decorate the interior because the pair seals the entrance of the hollow, leaving a small vertical slit. They use food and droppings to seal the entrance.

Wait, did you say that you saw a bird in the cavity? You are right. The female incubates the egg in the cavity for the next 50 days. She keeps the nest clean by throwing out uneaten food and the poop. The male bird brings food for the female and chicks.

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Rhinoceros Hornbill. Photo by Rhett A. Butler
Three months or 90 days after the chicks hatch, the female bird breaks out of the nest. The chicks then rebuild the covering and receive food from their parents for the next three months. When the chicks grow, they break the nesting hole and fly free.

The pair seals the entrance, except for a narrow vertical slit, with droppings and food. She lays one or two eggs, which are incubated for 37-to-47 days and the chicks fledge 86-to-97 days after the eggs are laid. The male feeds the female and chicks regurgitated, but not digested, fruit through the nest slit. The nest is kept clean and dry with feces forcibly ejected.

Now that the chicks are flying free, let us find out how to save them. The Rhinoceros hornbill is not threatened. Their tail feathers are used for decoration even today!

For teachers - here are some ideas to incorporate hornbills in lessons:


nnovativeclassroom.com - hornbill

You can watch a movie based on hornbill


  • May I use graphics from mongabay.com for my projects? Yes, you may provided that you don't remove the mongabay label from the images. You may use information from the site for class projects and can cite mongabay as the source.
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