Gibbons
Gibbons are acrobatic tree-dwelling primates characterized by their long limbs that allow them to swing through the trees. Their lack of tails and long, dense hair that ranges in color from cream to black also distinguish gibbons from other primates. Gibbons are very social animals that, unlike most other primates, often form long-term bonds and sometimes mate for life.
Despite being commonly referred to as monkeys, gibbons are actually classified as apes. However, they’re not considered great apes like their gorilla, orangutan, chimpanzee, and bonobo cousins. They are significantly smaller than the rest of the ape family, with most species falling between 40 to 65 centimeters (15-26 inches) in length and weighing between just over five kilograms (12 pounds) and seven and a half kilograms (17 pounds).
Gibbons are also endowed with a unique throat sac scientifically known as a symphalangus syndactyly, which allows them to modulate their vocalizations—or ‘sing’. Gibbons typically start each day by singing at sunrise, and they’re known to sing alone and in duets with the others in their family.
These lesser apes are most commonly found in the subtropical and tropical rainforests throughout southern Asia. The gibbon has long been celebrated in Chinese culture as a symbol of good fortune. In Doaist lore, the gibbon is considered the ‘superior life spirit’ as it’s regarded as a noble wanderer and poet with an elevated spirit of solitude.
However, this venerated species is among the most endangered of the ape family. It’s also among the most critically endangered of all primates in the world.
What is a gibbon’s scientific name?
Gibbons are scientifically of the family Hylobatidae. However, there are approximately 20 species of gibbons, which are divided into four genera:
- Hoolock
- Hylobates
- Nomascus
- Symphalangus
Molecular data indicates that these four genera groups are as distinct from one another as chimpanzees are from human beings. The primary factor that distinguishes them is their karyotypes (complete set of chromosomes).
Are gibbons endangered?
According to the International Union for Conservation of Nature (IUCN), gibbons’ status ranges from vulnerable to critically endangered, depending on the species—but most species are endangered or critically endangered.
While the Hainan gibbon (Nomascus hainanus) is listed as stable, the only surviving population of Hainan gibbons is restricted to a small stretch of forest in the Bawangling Nation Nature Reserve on Hainan Island, China. The rest of the island’s population of these gibbons is said to have been extinct for over 20 years.
Where do gibbons live?
Native gibbon habitats can be found throughout the rainforests of East, South, and Southeast Asia. You’ll find gibbons in China, Thailand, Cambodia, Laos, Vietnam, Myanmar, Bangladesh, India, Malaysia, and Indonesia—which includes the islands of Sumatra, Borneo, and Java.
More specifically, gibbons are arboreal primates. They spend most of their time in the upper and middle levels of the canopy of the trees. However, when they do make their way to the ground, they’ll typically walk or run on two feet while raising their long arms over their heads for balance.
Threats
While gibbons have a few natural predators—leopards, large snakes, and birds of prey—they aren’t actively hunted by these animals as they are quick and quite elusive. They are, however, under immense threat from both habitat destruction and hunting for traditional medicine and the pet trade.
Habitat destruction
Gibbons are incredibly vulnerable to human activities. Their rainforest habitats are currently facing total destruction and a complete loss of biodiversity due to deforestation. The current rate of habitat loss in Southeast Asia is among the highest in the world, with a 1.2% loss of rainforest annually.
The biggest drivers of habitat loss for gibbons are palm oil production and tree logging. As of today, approximately 84% of global palm oil production takes place in Indonesia and Malaysia—57% and 27%, respectively.
It should be noted that much of the land clearing carried out for palm oil plantations and agricultural purposes is done by intentionally setting fire to the forests. Not only do land clearing and logging destroy the precious gibbon habitat, but much of it is also carried out illegally.
Hunting
Poaching and capturing also pose a great threat to the gibbon populations as the illegal pet trade throughout Southeast Asia is very much alive and well. Young gibbons are often torn away from their mothers to be sold in wildlife markets as pets. Of course, the mother gibbon is often killed in order to separate the infant gibbon and both end up killed as a result of these attempts.
The same goes for using these animals to make traditional medicines. The flesh of hoolock gibbons has been used for centuries to combat anemia by cooking and consuming it. A paste is also made of the gibbon’s brain tissue, which is used to ease toothaches and headaches, while the blood is used to treat certain ailments, such as asthma, tuberculosis, and liver cirrhosis.
Hunting threats to gibbons also often extend to protected populations within national parks and wildlife reserves. This is due to the ongoing construction of roadways through protected areas, which causes fragmentation of gibbon habitats and makes them easily accessible to poachers.
FAQs
What do gibbons eat?
The gibbon diet consists mostly of fruit. However, when fruit is scarce, gibbons will scour the trees and rainforest floors for leaves, flowers, shoots, and insects.
They’ve also been known to eat young birds and bird’s eggs.
How many gibbons are left in the world?
It’s difficult to know for sure the exact number of gibbons left in the world as there are so many species of gibbons spread throughout the Asian rainforests. Plus, they can be very elusive, as they tend to hide high up in the tree canopies, making them difficult to count.
However, researchers have determined that all species of gibbons are declining in numbers. Some species are said to have as little as 30 individuals left in the wild. With conservation efforts in place, there is hope for the recovery of these species.
How much does a gibbon weigh?
The specific weight of a gibbon will depend on its species, as some are larger or smaller than others. However, the average weight of a gibbon is six to nine kilograms (13 to 20 pounds).
Smaller species of gibbon are known to weigh from five to eight kilograms (12 to 17 pounds).
How big are gibbons?
Gibbons are among the smallest of the apes. Of course, different species grow to different sizes.
Most gibbon species measure 40 to 65 centimeters (16 to 26 inches) from head to toe. The siamang (Symphalangus syndactylus) typically grows up to 90 centimeters (35 inches), making them one of the largest gibbons.
How long do gibbons live?
The average gibbon has a lifespan of up to 25 years in the wild. In captivity, gibbons can live up to 50 years.
The ongoing poaching and land clearing have significantly shortened the lifespan of most wild gibbons.
Are gibbons apes?
While commonly called a gibbon monkey, these special primates are, in fact, apes. They are not monkeys.
Gibbons are considered lesser apes as opposed to great apes, like their chimpanzee, gorilla, and bonobo cousins. This is due to their short stature and physiological makeup, which includes longer arms, denser hair, and a unique throat sac to amplify vocalizations.
Like great apes, however, gibbons do have a humanlike build and no tail. They also seem to lack the higher cognitive abilities and self-awareness of their great ape cousins—but that doesn’t mean they aren’t intelligent animals.
Do gibbons have tails?
No, gibbons do not have tails. This is part of what defines them as apes rather than monkeys, as all monkeys have noticeable tails (except for the barbary macaque monkey, which is a tailless ground-swelling species of monkey found in northern Africa).
How are gibbons affected by climate change?
Human-led climate change is directly impacting gibbons as habitat destruction and degradation due to land clearing and agriculture continues to worsen.
In the wake of climate change, regular seasonal occurrences have been thrown out of sync. This has caused a shift in the balance of the ecosystems, environment, and usual activities of the animals living among gibbons.
For example, the dry season that the Asian rainforests typically experience during the year has had more rainfall than usual. This directly impacts vegetation lifecycles, such as the typical fruiting season.
Instead of fruit, leaves begin to grow, and the flower that’s supposed to eventually turn into the fruit tends to die and fall off. This is causing gibbons—who are naturally frugivores—to seek out other sources of food, which means competing with other species in the rainforests and potentially starving to death.
Our work
In an effort to combat declining gibbon populations, IFAW has been hard at work stopping poachers and campaigning against gibbon trafficking.
Just recently, IFAW and partners Jakarta Animal Aid Network (JAAN) and the Wildlife Trust of India (WTI) came together to conduct an undercover investigation on the wildlife trafficking networks throughout Indonesia. We worked around the clock to find both physical and online traffickers across several time zones to monitor individuals on social media channels and messaging apps contributing to the illegal sales of gibbons and other precious species.
Acting as potential buyers, we contacted wildlife brokers and gained their trust in order to be invited to the sites where these animals were kept. From there, we collaborated with a special police unit to plan and execute a raid, during which arrests were made and the animals were rescued by JAAN for safety and rehabilitation.
Our work is incredibly risky and far from over. While the recent arrests have given us deeper insight into the criminal web of wildlife trafficking in Indonesia, wildlife trafficking is still an incredibly large and global business. The US Immigration and Customs Enforcement Agency estimates that wildlife trafficking is worth more than $10 billion (USD) annually—and criminal networks that have collectively amassed that kind of wealth will stop at nothing to keep individuals from investigating and outing them to the authorities.
IFAW and our partners will remain on the frontline of combatting online wildlife trafficking. We have been actively campaigning for over a decade via our Coalition to End Wildlife Trafficking Online, which works closely with law enforcement agencies, governments, online marketplaces, and social media platforms to gather information and monitor these online traffickers.
After launching the Coalition in 2018, we found nearly 12,000 protected wildlife species for sale online, through over 5,000 advertisements and listings on 106 marketplaces and four social media platforms. Since 2008, we’ve been partnering with online tech companies to shine a light on wildlife cybercrime and make it more difficult for these criminals to hide in plain sight.
From supporting enforcement of wildlife trade regulations to pushing for global public policy and creating consumer awareness, IFAW is working tirelessly to put an end to the illegal wildlife trade. Learn more about how we’re fighting wildlife cybercrime and how you can get involved.
How can you help?
Gibbons are experiencing population decline due to human activity and wildlife crime. IFAW is working to combat these issues affecting gibbons and other threatened species.