Indonesia: Javan gibbon returned to forest around West Java’s Mount Tilu

Arya Dipa The Jakarta Post 25 Apr 16;

Into the wild: Female Javan gibbon Tomtom leaves her habituation cage as she is released back into the wild by the Primate Rehabilitation Center at Mount Tilu Nature Reserve in Bandung regency, West Java.( JP/Arya Dipa )

Having spent three years at the International Animal Rescue ( IAR ) Primate Rehabilitation Center, Tomtom, an adult female Javan gibbon, has returned to the forest in the Mount Tilu Nature Reserve in Bandung regency, West Java.

Prior to the move to Mount Tilu, 6-year-old Tomtom had progressed to a habituation cage, a cage built in the forest to allow time for acclimatization to wild conditions, and when the cage door had been opened from afar, Tomtom is said to have shown no hesitation in leaving. Once Tomtom was outside the cage, she had leapt nimbly from one tree to another.

Sigit Ibrahim, an animal keeper at the rehabilitation center, explained that wild Javan gibbons were known use their arms more actively than their legs, adding that they survive in tree tops and rarely descend to the forest floor.

“They are very dependent on trees as they lead an arboreal life. So their arms are longer than legs,” said Sigit after Tomtom’s release.

The decision to release Tomtom back into the wild was based on her age as her fangs and genitals had sufficiently matured.

Sigit explained that Tomtom was not the first primate that the center had released back into the wild, having previously released six Javan gibbons and Surili Javan Leaf monkeys into the nature reserve.

Sigit said that the center had first begun to release primates at the Dewata Block in the Mount Tilu Nature Reserve in 2014.

“Tomtom was the first female gibbon released there, a male was released first. Now there is a couple” said Sigit, adding that, before she underwent rehabilitation, Tomtom had been kept as a pet by a resident until the age of three.

The International Union for Conservation of Nature categorized the Javan gibbon, a monogamous primate, as critically endangered.

Each pair usually has one or two offspring, with a gestation period of between 197 to 200 days and a pregnancy gap of three to four years between the first and second offspring.

“Before being released to the wild, the animal is required to have met certain criteria,” Sigit said.

“Firstly we need to ensure that the animal is free from contagious and deadly diseases; second, the animal must be familiar with forest surroundings and be accustomed to eating natural food as, once released, they can no longer depend on humans or animal keepers.

“A team will monitor Tomtom every day for the next six months using a radio transmitter installed underneath the skin on her back,” Sigit said.

Mount Tilu Nature Reserve head Didi Rustandi said that diversity remained quite high at the 8,000-hectare natural reserve. Based on camera traps, leopards have been observed in healthy condition, as have deer, wild boars and primates, including the Javan gibbon and Surili Javan Leaf monkey.

“Such releases are beneficial for the environment because wild animal can help preserve nature in the reserve,” said Didi.

Mekarsari village chief Atep Kurniawan agreed, saying that the reintroduction of the Javan gibbon or Javan silvery gibbon into the wild could help support the preservation of forest located in the upper part of the village.

“We villagers also depend on nature. People need water and if the forest is damaged we would be in trouble,” said Atep who issued a village regulation on the preservation of protected forest in the village in 2011.