Javan Gibbon Is Critically Endangered: Pet Trade and Habitat Loss Biggest Threats to Indonesia’s Primates
An ever increasing human population is putting pressure on Indonesia’s forests. One of the 14 species of gibbon, the Javan gibbon (Hylobates moloch) is in serious danger of becoming extinct as those forests disappear. The human fascination with exotic pets, especially primates, is another problem for Javan gibbons.
The Javan or Silvery Gibbon
The only critically endangered gibbon in Indonesia, the Javan or Silvery Gibbon, is restricted to small areas of western and central Java. These gibbons live in monogamous family groups with parents and juvenile offspring making up the social structure. They live almost entirely in the trees and can be highly aggressive to other gibbons entering their territory.
Javan Gibbons in the Pet Trade
Taking infant Javan gibbons for illegal trade as pets is a significant problem for two reasons. The obvious one is the loss of the young of the year from the population, reducing the potential future reproductive rate for the species.
But the method of capture presents an even bigger threat. Females are killed so the babies can be taken easily. Only limited numbers of wild animals survive to adulthood. Reproductive rates quickly drop if too many breeding age females are killed. Younger females may breed in this situation but they are often less able to rear their young properly.
Deforestation of Gibbon Habitat
Sadly, Indonesia has the world’s highest deforestation rate. These losses directly affect the Javan gibbons who need the fruit from the trees for food and the safety of the forest canopy for survival. As with the Hoolock gibbon, fragmentation of forest areas inhibits movement for the Javan species. This adds to the reduction in genetic diversity, as these monogamous primates are unable to join new social groups when they reach adulthood.
Efforts to Save the Javan Gibbon
Slowing the rate of deforestation, in particular reducing the fragmentation of forested areas by creating national parks and reserves and providing alternative means of employment and food production for the growing human population of Indonesia are the primary focus of Javan gibbon conservation work.
Nearly half of the wild population lives in three protected areas- Gunung Halimun National Park, Gunung Salak Protected Forest and Gunung Gede-Pangrango National Park. The areas are part of an integrated conservation management program which is attempting to maintain and increase their size and the wildlife corridors between them. As the area provides drinking water to Jakarta, the country’s capital, even those who have no interest in wildlife have a stake in maintaining the watershed.
Javan gibbons confiscated from the illegal pet trade, or voluntarily given up when awareness and outreach programs are successful, are being cared for at the Javan Gibbon Centre. While many of the confiscated gibbons will not be able to be returned to the wild, the young of those that reproduce may be used in reintroduction programs once genetic information is obtained.
This combined approach may help protect the Javan gibbon from the fate of the Chinese subspecies of White-Handed gibbon, which is now believed extinct.