Rarest Animals in the World: Species With the Fewest Survivors

How do scientists count rare animals?

Counting animals that are rare, shy and spread across forests or oceans is difficult, so every figure below is an estimate with a year attached. Researchers use camera traps, underwater microphones that pick up clicks, DNA from dung, footprint surveys and, for the very rarest, a name and radio tag for every animal. The IUCN Red List focuses on “mature individuals”, meaning adults able to breed, so the number of breeding animals can be far smaller than the total.

Rarest animals at a glance

1. Northern white rhino: 2 left

Only two northern white rhinos remain, a mother named Najin, born in 1989, and her daughter Fatu, born in 2000. They live under 24-hour armed guard at Ol Pejeta Conservancy in Kenya. The last male, Sudan, died in March 2018, so the subspecies of the white rhino is functionally extinct. Scientists have collected eggs from Fatu, made embryos with frozen sperm and plan to transfer them into southern white rhino surrogate mothers. In 2024 the team reported the first rhino pregnancy achieved by embryo transfer, an important step toward that goal.

2. Vaquita: about 7–10 left

The vaquita (Phocoena sinus) is the smallest living whale or dolphin, reaching only about 1.5 m (5 ft). The first full survey, in 1997, estimated 567 animals; by 2018 fewer than 19 remained. The cause is gillnets, especially illegal nets set for the totoaba, a large fish whose swim bladder is smuggled to Asia. A 2024 survey saw at least 6–8 vaquitas, and monitoring in 2025 identified 7–10, including new calves, which gives some hope. Read more in why is the vaquita almost extinct?

3. Hainan gibbon: about 42 left

The Hainan gibbon (Nomascus hainanus) lives only in the Bawangling area of Hainan Tropical Rainforest National Park on China’s Hainan Island. More than 2,000 lived across the island in the 1950s, but logging, rubber plantations and hunting cut the population to about 13 animals in two groups by 2003. Patrols and forest restoration have helped it grow slowly, and park officials counted about 42 gibbons in seven family groups in 2024, making it the rarest ape on Earth.

4. Sumatran rhino: fewer than 50 to 80

The Sumatran rhino (Dicerorhinus sumatrensis) is the smallest and hairiest living rhino and the closest living relative of the extinct woolly rhinoceros. The IUCN estimates fewer than 80 mature animals in scattered pockets of Sumatra and Indonesian Borneo, and the International Rhino Foundation puts the total at only about 34–47. The species died out in Malaysia in 2019. A breeding center at Way Kambas National Park in Sumatra has produced several calves, including births in 2022 and two in 2023.

5. Javan rhino: fewer than 100

All Javan rhinos (Rhinoceros sondaicus) live in a single place, Ujung Kulon National Park at the western tip of Java. The last one in Vietnam was poached in 2010. Indonesian officials gave a range of 87–100 rhinos in 2025, but the number is contested: in 2024, arrested poachers confessed to killing 26 rhinos for their horns between 2019 and 2023. Calves are still being born, and at least four were recorded between 2023 and 2024.

6. Saola: possibly a few dozen, or none

The saola (Pseudoryx nghetinhensis), sometimes called the Asian unicorn, is a forest ox discovered by scientists only in 1992, in Vietnam’s Vu Quang area. Trained biologists have never seen one alive in the wild, and the most recent confirmed record is a camera-trap photo from 2013. A 2015 estimate suggested 50–300 might survive in the mountains between Laos and Vietnam, but no one knows. Wire snares set for other animals are the main threat.

7. Amur leopard: about 130 left

The Amur leopard is a subspecies of the leopard that lives in the cold forests where Russia, China and North Korea meet. In 2007 only 19–26 were thought to survive. Protection in Russia’s Land of the Leopard National Park and cooperation with China have raised the count to about 128–130 sub-adults and adults in 2023, one of the strongest recoveries of any big cat.

8. Cross River gorilla: about 250–300 left

The Cross River gorilla is the rarest subspecies of western gorilla. Roughly 250–300 live in rugged hill forest along the border of Nigeria and Cameroon, split into about ten small groups that rarely meet. A 2014 survey estimated fewer than 250 mature animals. Forest loss isolates the groups, hunting remains a threat, and because females have a baby only every four years or so, recovery is slow.

9. Kakapo: 325 birds

The kakapo (Strigops habroptilus) of New Zealand is a flightless, nocturnal parrot and the heaviest parrot in the world, with males reaching about 4 kg (9 lb). Introduced cats, rats and stoats nearly wiped it out, and only 51 were known in 1995. Every bird now has a name and a radio transmitter and lives on predator-free islands. Kakapo breed only in years when rimu trees fruit heavily, and a bumper 2026 season with 90 fledged chicks lifted the population to 325.

10. California condor: about 600

North America’s largest land bird, with a wingspan of up to about 3 m (9.8 ft), became extinct in the wild in 1987, when the last 27 California condors were taken into captivity. Releases began in 1991, and in December 2025 the US Fish and Wildlife Service counted 607 birds, more than half of them flying free in California, Arizona, Utah and Baja California. Lead poisoning from eating contaminated carcasses is still the biggest threat.

11. Tapanuli orangutan: fewer than 800

Scientists described the Tapanuli orangutan as a new species only in 2017. Fewer than 800 live in about 1,000 km² (390 sq mi) of the Batang Toru forest in North Sumatra, making it the rarest great ape species. Roads, a hydropower project and forest clearing threaten to split its small range further.

Beyond mammals and birds: the Yangtze giant softshell turtle

Rare animals are not only mammals and birds. The Yangtze giant softshell turtle (Rafetus swinhoei), one of the largest freshwater turtles, is down to one or two known animals. The last known female in captivity died at Suzhou Zoo in 2019, and a wild female found in Vietnam in 2020 was found dead in 2023, leaving the species functionally extinct. Many rare insects, snails and plants have even fewer survivors but get far less attention.

Why are these animals so rare?

Most of the animals above were once far more common. Common causes include:

• Accidental capture: gillnets for the vaquita, wire snares for the saola.
• Poaching: rhino horn is still smuggled to illegal markets.
• Habitat loss: forest clearing for farms, plantations, roads and dams.
• Introduced predators: cats, rats and stoats on islands that had no ground-hunting mammals.
• Slow breeding: rhinos are pregnant for about 15–16 months, and kakapo breed only every two to four years.

Can the rarest animals recover?

Yes, if the main threat is removed. The kakapo has grown more than sixfold since 1995, the California condor more than twentyfold since 1987, and the Mauritius kestrel recovered from just four known wild birds in 1974. Recovery is expensive and slow, and once a species falls to a handful of animals, chance events such as disease or a storm can still finish it. For the full picture of Red List categories, see endangered animals, and for species already lost, recently extinct animals.