Rhinoceros Hornbill
Conservation Story
Nesting Behavior
The rhinoceros hornbill and the great hornbill have very similar nesting behaviors, though they are different species. Check it out!
NATURAL HISTORY
About the Rhinoceros Hornbill
Rhinoceros hornbills are one of more than 50 species of hornbills.
They live in dense old-growth forests in southeast Asia.
Their long bill helps them reach fruit and small animals.
They are important because they disperse seeds around the forest.
Both males and females have a large horn-like 'casque' on their bill.
Casques are made of keratin and are thought to amplify sound.
Males have red eyes and females have blue eyes.
Mated pairs will often stay together for life and nest in the same tree.
Bizarre Breeding
Rhinoceros hornbill reproduction is a very intense process that requires very specific environmental conditions.
Rhinoceros hornbills will lay their eggs hundreds of feet above the ground in cavities of old-growth trees. These cavities are often formed when an old branch falls off. The female will lay her eggs inside the cavity and then seal herself inside to incubate the egg using mud, food, and feces, leaving a small opening for the male to pass her food. She will remain inside the cavity with the chick for several months during which time she and the chick are entirely dependent on the male's success and survival. After roughly three months in the nest, the female will break out and reseal the chick inside the cavity. Both the male and female will collect food for the chick allowing it to grow rapidly. When the chick is about 80 days old, it will break out of the nest.
Conditions have to be favorable and tree cavities available for rhinoceros hornbill reproduction to be successful.
So, What's the Problem?
Because of the very specific conditions required and the high-risk strategy of reproduction utilized by the rhinoceros hornbill, changes to their ecosystem have made it hard for their populations to remain stable.
1
Deforestation
Across many parts of Southeast Asia, forests are rapidly being destroyed for lumber and agriculture. One of the largest threats to these forests is clearing to convert the land to palm oil plantations. Forests are cleared with massive, uncontrolled fires that destroy entire ecosystems in the blink of an eye and engulf native wildlife. As these forests are cleared, hornbills have fewer and fewer places to nest and trees that they have used for years are no longer available. Without the ability to reproduce, rhinoceros hornbill populations have dramatically declined.
2
Poaching
Though poaching does not pose as large of a threat as deforestation, it has certainly impacted their populations in many regions. Hunted for food, the bird trade, and their body parts, hornbills are a highly sought after target for some. Their feathers, beaks, and casques are often used in ceremonial dress and rituals and some body parts have commonly been used in traditional Chinese medicine. The rhinoceros hornbill shares its range with the helmeted hornbill, which is heavily poached for its ivory casque, and is often shot in confusion.
It is estimated that 43% of the rhinoceros hornbill's native range has been destroyed in the past 55 years.
Their population is listed as vulnerable by the International Union for Conservation of Nature.
Conservationists Take Action
Protecting rhinoceros hornbills means protecting so much more, including other species of hornbills and animals who require old-growth forests to thrive.
HUTAN is a conservation organization in Borneo, an island off the coast of SE Asia, that has worked to protect the primary forests and its inhabitants since the mid-1990s.
In 2013, HUTAN began working on artificial nest boxes that would be tied to old-growth trees in Kinabatangan in an effort to provide more nest sites to the 8 species of hornbills living in Borneo.
Through trial and error, nest boxes were modified to replicate natural cavities. Biologists monitored temperature and humidity and designed boxes to blend in with the natural environment.
With the help of many international zoos, several artificial nest boxes have been installed and monitored to continue making improvements.
How Are Hornbills Today?
Nest Boxes
Since the artificial nest box project began in 2013, more than 20 boxes have been installed in the forests of Kinabatangan. Nest boxes are monitored with camera traps.
Boxes in Use
In the past few years, several artificial nest boxes have been used by a variety of hornbill species. The first rhinoceros hornbill chick fledged from an artificial nest box in July 2017. Squirrels, civets, and bees have also been observed using the boxes, which are suspended more than 60-feet off the ground.
Still Learning
Through observing the boxes, biologists are learning which nest boxes are used the most and continue to make improvements. It seems hornbills like the plastic drums better than the wooden barrels!
How You Can Help Hornbills
Shop Palm Oil Friendly
Buying items made with sustainable palm oil ensures that you are not contributing to deforestation! Look for the RSPO sticker on food, cosmetics, and so much more or scan products with the Cheyenne Mountain Zoo app!
Be an Advocate
As one person, you make a difference. As a team, we can make an even bigger difference. Now that you know supporting sustainable palm oil will help save tons of species and forests, tell your friends so they can decide to help hornbills, too.
Financial Support
Hornbill research, monitoring, nest building, forest restoration, and everything else that comes with hornbill conservation can be quite expensive. Donations to BirdLife or the Hornbill Research Foundation will support continued conservation!
