Sumatran Rhinoceros - Distribution and Habitat

Distribution and Habitat

The Sumatran rhinoceros lives in both lowland and highland secondary rainforest, swamps and cloud forests. It inhabits hilly areas close to water, particularly steep upper valleys with a lot of undergrowth. The Sumatran rhinoceros once inhabited a continuous range as far north as Burma, eastern India and Bangladesh. Unconfirmed reports also placed it in Cambodia, Laos and Vietnam. All known living animals occur in Peninsular Malaysia, the island of Sumatra and Sabah, Borneo. Some conservationists hope Sumatran rhinos may still survive in Burma, though it is considered unlikely. Political turmoil in Burma has prevented any assessment or study of possible survivors. The last reports of stray animals from Indian limits were in 1990s.

The Sumatran rhino is widely scattered across its range, much more so than the other Asian rhinos, which has made it difficult for conservationists to protect members of the species effectively. Only six areas are known to contain communities of more than a handful of Sumatran rhinoceros: Bukit Barisan Selatan National Park, Gunung Leuser National Park, and Way Kambas National Park on Sumatra; Taman Negara National Park in Peninsular Malaysia; and the Tabin Wildlife Reserve in Sabah, Malaysia on the island of Borneo.

The Kerinci Seblat National Park, Sumatra's largest, was estimated to contain a population of around 500 rhinos in the 1980s, but due to poaching, this population is now considered extinct. The survival of any animals in Peninsula Malaysia is also in doubt.

Genetic analysis of Sumatran rhino populations has identified three distinct genetic lineages. The channel between Sumatra and Malaysia was not as significant a barrier for the rhinos as the Barisan Mountains along the length of Sumatra, for rhinos in eastern Sumatra and Peninsular Malaysia are more closely related than the rhinos on the other side of the mountains in western Sumatra. In fact, the eastern Sumatra and Malaysia rhinos show so little genetic variance that the populations were likely not separate during the Pleistocene, when sea levels were much lower and Sumatra formed part of the mainland. Both populations of Sumatra and Malaysia, however, are close enough genetically that interbreeding would not be problematic. The rhinos of Borneo are sufficiently distinct that conservation geneticists have advised against crossing their lineages with the other populations. Conservation geneticists have recently begun to study the diversity of the gene pool within these populations by identifying microsatellite loci. The results of initial testing found levels of variability within Sumatran rhino populations comparable to those in the population of the less endangered African rhinos, but the genetic diversity of Sumatran rhinos is an area of continuing study.