We're lucky enough to care for two gibbon species at the Zoo, the endangered Javan Gibbon and critically endangered Northern White-cheeked Gibbon.

Gibbon calls are among the loudest in the primate world.
 
But while both Javan and Northern White-cheeked Gibbons are known for their impressive vocalisations, they’re distinctly different. 
 
Northern White-Cheeked Gibbons are famous for their perfectly coordinated duets.
 
Most mornings, the female and male pair come together to perform what is known as a true duet used to mark their territory, strengthen pair bond and attract a mate.
 
This is a highly coordinated acoustic performance, where the males sings an introduction phase that sets the rhythm, followed with the female singing her great call. The female call is the acoustic centrepiece of the entire duet.
 
At the Zoo you can hear the duets of Zoo pairs, Kayak and Jermei and Lulani and Nakai echoing throughout the entire Zoo, as they reside at opposite ends of the Zoo grounds.
 
The delightful duet make for a memorable arrival for visitors and mark the start of the day for Zoo staff and volunteers.




On the other side of the lake the Javan Gibbons have a different approach.
 
Rather than coming together in unity they sing sex-specific solo songs.
 
Unlike their white-cheeked gibbon neighbours, these apes don’t always call every day but instead call sex specific solo songs, for example the female may be alerting the group to danger and the male will patrol the territory and if required will join in.
 
Gibbons have large home ranges in the wild, so their complex vocalisations and songs are important for group cohesion and defending territories.
 
The resident Javan Gibbons, Sunda who is mother to Asta, will sing together however due to Sunda not currently having a mate this does impact her vocal repertoire. But with Asta growing into his role as an adult male, Sunda is helping him learn all there is to know about singing.

With no danger to worry about, our resident Javan Gibbons, Asta and Sunda, rarely sing together.



The next time you hear the calls of the gibbons, take a moment to listen.

Because while their voices carry across the Zoo every day, they're becoming increasingly rare in the wild.

Sadly, wild populations of both gibbon species are steadily declining due to significant threats including the illegal wildlife trade and habitat loss.

That’s why we proudly partner with Fauna & Flora Vietnam, supporting critical field work in Pu Mat National Park to protect the largest wild population of White-cheeked Gibbons from poachers and wildlife traffickers. 

Our support helps to upskill their rangers and local community conservation team members with specialisted training on accoustic surveys to track the voices of gibbon species and population locations. 

You can hear the voices of our Northern White-cheeked Gibbons and Javan Gibbons every day from 9am-5pm with the best time at the Free Gibbon Keeper Talk from 10:15 AM and 1:45 PM.