The Javan Rhino Is the Rarest Living Rhinoceros Species

Little is known about the Javan rhinoceros (Rhinoceros sondaicus). It is approximately 6 to 11 feet (2 to 3.2 meters) long and weighs about 2,000 to 5,100 pounds (900 to 2,300 kilograms), making it about the size of a black rhino.

Despite its imposing size, pointy horn and tusk-like lower incisors (which it uses to fight other rhinos), Javan rhinos, like other rhino species, are grazers, eating fallen fruit and other plant material.

Javan rhinos are one of three Asian rhino species; there are five rhino species total. The other Asian rhinos are the Indian rhino (Rhinoceros sunicornis) and the Sumatran rhino (Dicerorhinus sumatrensis).

Both Indian and Javan rhinos possess a single horn, but the Indian rhinoceros is larger. The Sumatran rhino is easily distinguishable from the other two Asian rhinos because it has two horns, like the two African rhino species.

The Javan rhino was previously found throughout South and Southeast Asia but is now found in just one national park in Java, Indonesia. Hunting (for its horn) and habitat loss due to human encroachment nearly wiped out the entire species.

Two Javan rhino subspecies are now extinct — Rhinoceros sondaicus inermis of Bangladesh, Myanmar and northeast India, and Rhinoceros sondaicus annamiticus of Cambodia, eastern Thailand, Laos and Vietnam.

The International Union for Conservation of Nature declared the Javan rhino critically endangered in 1996.

Javan Rhino Threats

Today, the main threats are low genetic diversity, loss of food plants and lack of captive breeding.

Arenga palms, or langkap, are fast-growing trees that dominate the forest canopy, preventing other plants — including the plants the Javan rhino eats — from growing. In 2011, conservationists began removing Arenga palms from Ujung Kulon National Park to increase the amount of viable habitat for the rhinos.

Another challenge in Javan rhino conservation is that this rhinoceros has never been bred in captivity. The last captive Javan rhino died in 1907. Without a successful captive breeding program, it will be impossible to increase this critically endangered species' population beyond Ujung Kulon National Park.

With the entire Javan rhino population in one area, the last of the species could be wiped out by a natural disaster or disease.

How Many Javan Rhinos Are There?

The remaining Javan rhino population totals less than 100; it is one of the rarest large mammals in the world. In October 2023, a Javan rhino calf was born in Ujung Kulon National Park, bringing the population total to an estimated 81 individuals as reported by NBC News.