In 2003, the Hainan gibbon was the rarest primate on Earth.
Not one of the rarest. The rarest. A distinction that carried almost unbearable weight: 13 individuals, surviving in a single patch of tropical rainforest in China's Hainan Province, with nowhere else to go and no margin for error. An entire species, a million years of evolutionary history, a particular way of moving through the canopy and calling to the morning — compressed into a group of animals you could count on two hands.
The numbers in the 1950s told a different story. Back then, an estimated 2,000 Hainan gibbons ranged across the island. Decades of deforestation and hunting took that down to 13. A 99.35% collapse.
Now, in early 2026, the count stands at 42 — across seven family groups.
It is still a devastatingly small number for a species. But it is also a tripling. And in conservation, a tripling from the edge is not a small thing. It is the thing people work lifetimes for.
The recovery has been slow and methodical, driven primarily by the Kadoorie Conservation China Department in partnership with local authorities and Hainan Tropical Rainforest National Park. Their approach has been unglamorous: studying gibbon behaviour, working with local communities, planting the fruit trees the gibbons prefer, and protecting the remaining forest with sustained vigilance. No single breakthrough. Two decades of showing up.
The population reached 30 individuals in 2020 across five family groups. By 2022, it had risen to 37. By 2024, to 42 — the highest count in over 40 years.
In a further surprise, recent genetic analysis has revealed that the Hainan gibbon's DNA is in better shape than scientists feared. Despite passing through such a severe population bottleneck, the species retains surprisingly healthy genetic diversity — the result, researchers believe, of having previously rebounded from another crash during the last Ice Age, and of a recent natural reconnection between two long-separated genetic lineages.
Conservationists are now focused on the next phase: building habitat corridors to connect isolated forest fragments, reducing inbreeding risk as the population expands, and giving the species room to keep growing.
Forty-two is not enough. But 42 is 29 more than 13.
And 13 is not 0. 🦧