Hainan gibbon: the song of the world's rarest primate

Meet the Hainan gibbon

The Hainan gibbon is a small, tailless ape built for life in the trees. With long, powerful arms and elongated fingers, it swings from branch to branch — a way of moving called brachiation. Active by day, it almost never comes down to the ground.

Males and females look nothing alike. The male is jet black, with a small crest on his head and sometimes golden cheeks. The female wears a golden or cream coat with a black cap on top of her head. Oddly enough, every baby is born very pale and then turns black; females only regain their light colour once they reach adulthood.

It feeds mainly on fruit, such as figs and wild lychees, along with seeds and the occasional insect. It lives in families made up of one male, two females and their young. Females usually stay in the family they were born into.

Every morning, shortly before or after sunrise, the families sing. Their powerful songs, which carry up to two kilometres, help attract a mate, strengthen family bonds and mark out territory. Scientists also use them to count the gibbons.

Did you know? In 2016, researchers described “juggling” behaviour in Hainan gibbons — something never reported before in any non-human primate. This shy ape is still full of surprises.

Why it is endangered

In the 1950s, around 2,000 gibbons lived on Hainan Island. Hunting and logging then devastated the species. By the early 1980s, it survived only in Bawangling, one of the island’s last tropical primary forests. By 2003, just two families — 13 animals — were left.

Hunting is now under control, but a population this small faces other dangers:

• A tiny home. All the gibbons live in a single forest of about 15 km². The surrounding forests are damaged and fragmented, which makes them hard to settle.
• Inbreeding. According to the 2025 study, genetic diversity is far lower than it once was, and new pairs are increasingly closely related. The researchers sequenced the genomes of 18 of the 21 adults. They warn against capturing wild gibbons for captive breeding, which could reduce that diversity even further.
• Extreme events. A typhoon, a disease outbreak or a poor breeding season could be enough to tip a population of a few dozen animals over the edge.

What is being done to save it

Since 2003, the Hong Kong organisation Kadoorie Farm and Botanic Garden has worked with the Bawangling reserve. It trains and funds gibbon monitoring teams, supports anti-poaching patrols and runs annual censuses. It is also replanting the fruit trees gibbons feed on, to restore degraded lowland forest. In the nearby village of Qingsong, it helps residents develop livelihoods that spare the forest, such as eco-friendly beekeeping.

In 2014, a typhoon triggered a landslide that tore a wide gap in the canopy, right in the middle of gibbon territory. In 2015, professional tree climbers strung a 15.8-metre rope bridge across it. The gibbons ignored it at first, then started using it after 176 days — especially females and youngsters.

In October 2020, China created the Hainan Tropical Rainforest National Park, with the gibbon as its flagship species. Teams from the Zoological Society of London listen to the forest with automatic recorders, and artificial intelligence then analyses the songs.

The work is paying off: from 13 gibbons in 2003, numbers rose to 33 in 2020, then to 42 in 2025. To understand them better, researchers got two families used to their presence between 2021 and 2022 — the largest set of observations ever gathered on the species. The 2025 study brings more good news — the gibbons find enough food and breed well. Compared with other gibbons, females give birth at shorter intervals and young males leave home earlier: both signs of a healthy population. The priority now is to give them more room by creating forest corridors to neighbouring forests, so young gibbons can start families away from their relatives.

How you can help

Sauvons les animaux does not collect donations. These recognised organisations work for the Hainan gibbon:

• Kadoorie Farm and Botanic Garden has run the field programme on Hainan since 2003. Its donation form is general. Donate to KFBG
• Zoological Society of London supports reconnecting the forest and acoustic monitoring of the gibbons. Donate to ZSL

And in everyday life:

1. Help its story be heard. The Hainan gibbon is rarer than the giant panda, yet almost nobody knows it exists.
2. Never share videos of monkeys kept as pets. They fuel the illegal primate trade.
3. Support tropical forests by choosing wood and paper from sustainably managed forests.