Javan Rhinos

Less than 100 Javan Rhinos survive in a single national park in Indonesia. Learn about this Critically Endangered species and how Re:wild and partners are working to recover it.

There are fewer than 100 Javan Rhinos left on Earth.

Among the most reclusive animals on Earth, Javan Rhinos roam the dense forest of Ujung Kulon National Park largely unseen — even by the rangers who dedicate their lives to protecting them.

Most of what we know about them comes from camera traps.

Every individual has a name. Every birth matters.

This is what it looks like to protect a species at the very edge of survival.

Javan Rhino Facts at a Glance

Scientific Name
Rhinoceros sondaicus
IUCN Status
Critically Endangered
Population
Less than 100 individuals

Weight
2,000 to 5,100 pounds (900 to 2,300 kg)
Height
5 to 5.5 feet at the shoulder (1.5 to 1.7 m)
Lifespan
35 to 40 years

Diet
Browser; feeds on leaves, shoots, twigs, and fallen fruit across more than 300 plant species
Habitat
Dense tropical rainforest with access to water and mud wallows
Range
Ujung Kulon National Park, Java, Indonesia

The Javan Rhino is one of the rarest large mammals on the planet.

Less than 100 individuals survive. There is no captive backup anywhere in the world. What exists in the wild is everything the species has left.

The Javan Rhino is a large, heavily built browser with grey skin that folds into plates around the body, giving it a distinctive armored appearance. Only males carry a visible horn. Females have a very small horn or none at all. They are solitary animals, moving quietly through dense rainforest and feeding on more than 300 recorded plant species. Mothers raise calves alone, with females giving birth to a single calf roughly every three to five years after a gestation of around 16 months.

They are also a keystone species. As they move through the forest foraging and disturbing vegetation, they create conditions that benefit other species and help the ecosystem maintain its health and structure.

The Javan Rhino was not always confined to a single peninsula.

Historically, the species ranged from the foothills of the Himalayas through India, Bangladesh, Myanmar, Thailand, Laos, Cambodia, Vietnam, Malaysia, and across the Indonesian islands of Sumatra and Java.

Hunting and habitat loss compressed that range over centuries. By the mid-twentieth century, only a remnant population remained in Ujung Kulon and one in Vietnam, however the last Javan Rhino on mainland Southeast Asia was shot by poachers in Vietnam in 2010.

No Javan Rhinos exist in captivity anywhere in the world.

This small population is threatened by poaching, disease, volcanic eruptions, and tsunamis.

Poaching
Demand for rhino horn persists and all rhino species require constant protection from poaching.
Disease
Domestic livestock near the park carry diseases that can spread to wildlife through biting flies.
Volcanic Eruption
Anak Krakatau, an active volcano 55km from the park, poses a direct threat to the entire population.
Tsunami
A major eruption or undersea earthquake could trigger a tsunami capable of overwhelming Ujung Kulon's low-lying coastal habitat.
Small Population
The small number of individuals combined with the social structure, ranging patterns of the species, and the long time the population has been isolated means that the levels of inbreeding are likely very high.
Habitat Pressure
The Arenga palm, Arenga (Arenga obtusifolia), is spreading through core rhino habitat, crowding out the plants rhinos depend on for food.

Re:wild and partners have a plan to protect this species and put it on the path to recovery.

Re:wild, Edge Group Conservation, and partners are supporting the Government of Indonesia and local conservation partners to protect every animal in Ujung Kulon, grow the population, with the goal to establish a second population at a separate site.

Every part of the plan is connected. Stronger protection reduces poaching risk. Better monitoring means faster response to threats. Habitat improvement means more food, more calves, and a healthier population. And advanced science means that even the genetic diversity of animals that cannot breed naturally can be preserved and used.

Protecting every animal
Anti-poaching patrols, AI-enabled camera traps, and a digital radio system keep rangers connected and threats visible in near real time.
Monitoring the population
Every individual is tracked. Camera trap data tells us how many calves are born each year, which females are breeding, and how the population is changing.
Improving habitat
Controlling the invasive Arenga palm inside Ujung Kulon restores browse for rhinos and increases the park's capacity to support a growing population.
Advanced science
Working with Bogor Agricultural University with support from the Colossal Foundation the genetic diversity of the remaining population is being banked and we are exploring cloning and advanced reproductive technologies to grow the population.
A second population
Establishing a second Javan Rhino population at a separate site is the long-term goal. Planning is underway.