With such a small population of Javan rhinoceros left, the species’ survival is threatened by low genetic diversity, the likelihood of inbreeding, and the potential of natural disasters.
There are still major gaps in our knowledge about Javan rhinoceroses because they are extremely difficult to study and there’s a remote possibility that remnant, undiscovered populations exist.
The Javan rhinoceros is generally solitary, except for mating pairs and mothers with their young.
There is little sexual dimorphism in the Javan rhinoceros, however females have shorter, less prominent horns or may lack a horn, entirely.
The Javan rhinoceros’ gestation and inter-birth intervals are unknown, but are presumed to be similar to other rhinos, with a single calf being born after a gestation of 15-16 months every 2-3 years.
60% of Eastern Asian doctors stock rhino horn, with Asian horns, like that of the Javan rhinoceros, preferred over those of African species.
The Javan rhinoceros has a unique, prehensile, pointed, upper lip that functions as an aid for feasting and grasping onto leaves.
Although the Javan rhinoceros’ habitat was once protected in Vietnam, it has now lost most of its forest habitat due to habitat loss, degredation, agricultural purposes, and other human activities.
The Javan rhinoceros has poor eyesight, but keen senses of smell and hearing despite having smaller ears than other rhinoceroses.
A young Javan rhinoceros will be active shortly after birth and will be suckled by its mother for 1-2 years.
During colonial times, Javan rhinoceroses were killed by trophy hunters, but now, they’re relentlessly poached for their horns and meat as rhino horn can sell for $60,000/kg.
The Javan rhinoceros is threatened by the invasive Arenga palm, which is having a devastating impact on the plants the rhino relies on for food.
The Javan rhinoceros population in Ujung Julon National Park has been increasing over the past 5 years and the feasibility of establishing a second population in another suitable, secure habitat is being considered.
Although there’s historically been 22 captive Javan rhinoceroses, none are currently captive and the species has never bred in captivity.
Following the Vietnam war in 1975, the Javan rhinoceros was thought to be extinct in Vietnam, but was later spotted in the area in 1999.
The Javan rhinoceros is a pure, herbivorous browser but was historically a mixed feeder, a more adaptable feeder than other rhinos.
The Javan rhinoceros mates between July and November and females become sexually mature earlier than males.
The Javan rhinoceros’ scientific name, Rhinoceros sondaicus, comes from Greek and Latin referring to its horned nosed and locality in the Sunda islands of Indonesia.
For decades, Javan rhino populations have hovered around 50 animals, the effective carrying capacity of the area which they reside, with an estimated 46-67 alive today.
The Javan rhinoceros is one of 5 extant rhino species within the Rhinocerotidae family and has 3 recognized subspecies, though 2 are now extinct.
Although the Javan rhinoceros used to roam across a vast portion of Asia, it can now only be found in west Java, Indonesia.
The Javan rhinoceros is smaller than most other rhinos as average adults stand 5-6 ft at the shoulder and span 11-12 ft in lenth.
As in other ungulates, the Javan rhinoceros’ teeth are lophodont, having transverse ridges on the grinding surfaces.
The Javan rhinoceros is an odd-toed terrestrial ungulate as each of its feet ends in three hooved toes.
The Javan rhinoceros’ single horn is the smallest of all rhinos, growing to a length of 25cm (10in).
The Javan rhinoceros’ hairless skin is a dusky, hazy grey and contains tough folds that create an armor-like plating.
The Javan rhinoceros subspecies, Rhinoceros sondaicus annamiticus, used to reside in Cat Tien National Park in Vietnam, but became extinct in 2011 due to poaching.
The Javan rhinoceros looks similar to the Indian rhinoceros, but is slightly smaller with a much smaller head and looser, less apparent skin folds.
Do you think you know the Javan rhinoceros? Test your knowledge of Javan rhinoceros FaunaFacts with this trivia quiz!
Indonesia’s remote Ujung Kulon National Park on the island of Java holds the only viable population of the Javan rhinoceros, guarded from poaching by IRF Rhino Protection Units.
The Javan rhinoceros is a lowland species that resides in incredibly dense, low-lying tropical rainforests and prefers areas with abundant water and mud wallows.
The Javan rhinoceros’ range extends between 3-20 sq m, with various groups having overlapping ranges and males wandering over larger areas than females.