Gibbons, commonly called lesser apes, aren’t as well-known as some of their great ape cousins like chimpanzees or gorillas. But the lives of these highly arboreal primates are no less fascinating. They reside in the canopy of the tropical forests of South and Southeast Asia, living in small family groups, each patrolling its own territory, and communicating through highly musical, haunting songs. Their diet, consisting predominantly of fruits, makes them key seed dispersers.
Yet gibbons are among the most threatened primate groups in the world: of the 20 known species, five are listed as critically endangered on the IUCN Red List, and 14 are endangered. All gibbon species are targeted by the international wildlife trade.
Today, on International Gibbon Day, we present some recent Mongabay stories about these agile, long-limbed apes.
Signs of hope
The endangered Javan gibbons (Hylobates moloch), found only on the Indonesian island of Java, are mostly confined to small forest patches today. Two such groups have become isolated from a larger forest area by farms and settlements in Central Java province.
A local NGO, SwaraOwa, is working with farmers in the region to cultivate native trees and plant them to build forest corridors, Mongabay reported in a video published in June. The gibbon population there has increased from about 800 individuals 10 years ago to 1,000 in 2023.
“Our motivation as young people is that future generations will not just hear stories about the gibbons, they’ll be able to see them from their backyards if they want,” said Rohim, a Mendolo farmer.
Meanwhile, in the remote forests of northern Vietnam, a community conservation team saw two baby Cao-vit gibbons (Nomascus nasutus), one of the world’s rarest apes, Kristine Sabillo reported in March. This critically endangered species survives only in a fragmented forest patch bordering Vietnam and China, and female gibbons give birth only once every four years or so, making this sighting a rare one.
Increase in gibbon trafficking
There’s growing demand for gibbons as pets. India, for instance, has seen an increase in seizures of gibbons at its airports and border areas, Mongabay’s Spoorthy Raman reported in January. Most of these gibbons, such as the siamang (Symphalangus syndactylus) and the agile gibbon (Hylobates agilis), come from the forests of Southeast Asia.
The gibbons in the pet trade are usually caught when they’re young, said primatologist Susan Cheyne. “The only way to get a young gibbon from a species that lives 30-40 meters [100-130 feet] up in the tree is to kill the mum.”
The siamang in particular has become one of the most trafficked apes globally, conservationist Sinan Serhadli wrote in a commentary. Found in the forests of Indonesia, Malaysia and Thailand, it’s the largest of all gibbon species, slower moving, and easier to catch.
“The crisis is a huge conservation issue that is undermining healthy and viable populations,” Serhadli wrote, “while also being a crisis of immense cruelty and suffering.”
Banner image: White-handed gibbon in Thailand by JJ Harrison via Wikimedia Commons (CCBY3.0).
Credits
