JAVA — Indonesia. Throughout the misty mountains of central Java, the call of the Javan gibbon (Hylobates moloch) once echoed throughout the forest. Today, their voices are fading. Java is one of the most densely populated regions on Earth, and decades of logging, agriculture and infrastructure development have fragmented the forest, while rampant hunting and the illegal pet trade have also taken their toll.
With only an estimated 4,000 Javan gibbons left in the wild, they are now listed as endangered on the IUCN Red List. Many of the remaining populations have been left stranded in disconnected patches of forest, unable to move without uninterrupted canopy cover. Conservationists warn this isolation makes them vulnerable to disease and limits their ability to find mates, leading to inbreeding.
To address this, local NGO SwaraOwa has been working with local communities to reconnect these isolated areas of forest. By planting “forest corridors,” stretches of native trees that link up isolated forest blocks, they hope to provide a green pathway for gibbons to find their way back into larger areas of forest, and the other gibbons that live there. The corridors not only allow the gibbons to move, but also support countless other species that depend on Java’s forest ecosystems.
SwaraOwa believes working with the local community is the key to success. Young farmers in Medolo village have taken the lead in growing native seedlings and restoring key areas between forests. As trees begin to take root and corridors expand, conservationists and locals alike hope the gibbon’s call will once again ring across Java’s forests.
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Banner image: Javan gibbon (Hylobates moloch). Image ©Nanang Sujana.
Transcript
Notice: Transcripts are machine and human generated and lightly edited for accuracy. They may contain errors.Every morning the gibbons do their routine
“great call” to mark their territory.
You can usually hear it from 5 a.m.
to around 9 or 10 a.m.
That’s the Javan gibbon, if we’re here we have to be quiet,
because they’re very sensitive when
they see the monitoring team.
There are five members in this group of Javan gibbons
and there are indications that they’re isolated
and can’t cross [to the big forest].
So where we are now is the
tropical lowland forest of Java.
In the central part of Java,
this is the last one remaining.
Elsewhere the forest has disappeared;
there are lots of people, lots of development.
Across all of Java, there are about
4,000 individual Javan gibbons left
and they’re found only on Java.
From the results of our research, there is indeed
a group of Javan gibbons behind the hill there,
they cannot go anywhere else because they are
surrounded by anthropogenic activities,
there are farms, rice fields and settlements.
From about 2000 until the end of 2010,
hunting of primates was still massive,
especially gibbons and langurs.
Sometimes people hunted them to sell their meat, sometimes to sell their offspring.
But then SwaraOwa informed us that in the village
of Mendolo there lived five endemic primates of Java.
That was a point of pride for us, we were like,
“Wow, we have to protect them.”
We have created a map that illustrates the condition
of habitat fragmentation in this village.
There are at least two forest blocks that are no longer
connected to the large area of forest here.
This main forest is still quite large,
but this one is almost 100% isolated.
There are two groups of gibbons here,
one group has four individuals
and the other has five individuals.
And this is in a forest of just 4-5 hectares.
That is actually a pretty critical condition.
After we agreed that there was a problem
in the habitat of the Javan gibbon,
we created a community-based conservation scheme,
which prioritized the involvement or
participation of the community.
Some of the village youths were also recently concerned about the decline in quality of the forest,
so we carried out tree planting.
So the young Mendolo farmers took the initiative
to protect the ecosystem in Mendolo village.
In 2023 we started cultivating
pucung trees (Pangium edule) in a nursery,
and by the grace of God they’ve all been planted.
And last year we started cultivating timber trees
that are native to the Mendolo village forest.
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.
As of this second year of planting we’ve
already planted about 500 trees,
and our target is to reach 800 at the end of the two years.
Up here you can see that the habitat has been opened,
on both sides of the river.
We prioritize planting in habitats like this,
because besides being a corridor for gibbons,
it also helps with water conservation
and preventing landslides.
For the population in this mountainous landscape
that we surveyed, around 1,000 individuals,
that was our last survey in 2023.
The population in this landscape
10 years ago was around 800.
So there has been a 20% increase in
population over the past decade.
That’s given us optimism that the future
for the gibbons in this area looks bright.
But we also have to look ahead to how we can
continue to strengthen its protection,
because this is not a conservation area.
So how can we involve residents around this forest
so that they have a sense of ownership,
<b>that this is a source of wealth for the future?</b>