Javan rhinoceros  (Rhinoceros sondaicus)

Classified as Critically Endangered (CR) by the IUCN Red List 2007 (1), and listed under Appendix I of CITES (3). Subspecies: the Vietnamese Javan rhinoceros (Rhinoceros sondaicus annamiticus) and the Indonesian Javan rhinoceros (R. s. sondaicus) are both classified as Critically Endangered (CR) (1).

The prehistoric-looking Javan rhinoceros is one of the world’s rarest large mammals (2). The name rhinoceros derives from the Greek for 'nose horn', and the Javan rhinoceros has a single horn on the snout that, like all rhinoceros horns, does not have a bony core but is composed of keratin fibres (4). Adults are grey in colour, and have an armour-plated appearance caused by the deep folds of hairless skin (5).

Once widespread in south-east Asia, the Javan rhinoceros is now found only in two small areas. The Indonesian Javan rhinoceros subspecies, (Rhinoceros sondaicus sondaicus), is found in a single population within the Ujung Kulon National Park in Java (6). The Vietnamese Javan rhinoceros, (R. s. annamiticus), is perched on the very brink of extinction, as it is thought that only around ten individuals persist in the Cat Tien National Park in the Dong Nai region of Vietnam (6).

The Javan rhinoceros inhabits dense rainforests with mud wallows and plenty of water, showing a preference for low-lying sites (2).

Little is known of this exceptionally rare mammal. It is mainly a browser of leaves, twigs, fruits and shoots and often breaks saplings down to access food (4). Females reach sexual maturity at about five to seven years of age, whereas males become mature later, typically at about ten years of age (5). The rate of reproduction in this species is relatively slow; females give birth to a single young every one to three years, after a presumed gestation of 15 to 16 months, as in other rhinos. With the exception of mothers with their offspring and mating pairs, the Javan rhinoceros is a largely solitary species (5).

The devastating decline the Javan rhinoceros has been largely attributed to hunting for its horn, and for other body parts which are used in traditional Chinese medicine (6). In addition, habitat loss resulting from logging activities and development has impacted the species, and the two critically small populations are also exceptionally vulnerable to disease and natural disasters, both of which could wipe out an entire population (6).

In Indonesia, the Javan rhino has been legally protected since 1931, and Ujung Kulon National Park was set aside for the conservation of this species. The protected area in which the Vietnamese Javan rhinoceros occurs, (previously known as the Cat Loc Nature Reserve), was, for many years, ineffectively protected (6), but since the Cat Loc area was integrated into the Cat Tien National Park in 1998, more forest guards have been deployed, and the conservation organisation WWF has been supporting these teams with better equipment and allowances (7).

In 1998, WWF also launched the Asian Rhino and Elephant Action Strategy (AREAS), which specifically tackles the issue of habitat loss (7).

A Status Survey and Conservation Action Plan for Asian rhinos, published in 1997 by the World Conservation Union (IUCN) Asian Rhino Specialist Group, suggests that the possibility of moving some of the rhinos into another area should be looked into (6). This would help lessen the chance of disease or a natural disaster affecting all individuals simultaneously. The action plan also suggests that bringing some of the rhinos into a managed, breeding sanctuary should be considered (6).

With so few Javan rhinoceros remaining however, some conservationists are worried that these measures may be too late to save this rare species, teetering on the brink of extinction.

View information on this species at the UNEP World Conservation Monitoring Centre.

For further information on the Javan rhinoceros see: 

• International Rhino Foundation:
  www.rhinos-irf.org
• EDGE of Existence:
  http://www.edgeofexistence.org/mammals/species_info.php?id=11