The Sumatran rhinoceros once inhabited rainforests, swamps and cloud forests in India, Bhutan, Bangladesh, Myanmar, Laos, Thailand, Malaysia, Indonesia and southwestern China, particularly in Sichuan.

It is the most vocal rhino species and also communicates through marking soil with its feet, twisting saplings into patterns, and leaving excrement.

[11] The Indonesian ministry of Environment, began an official counting of the Sumatran rhino in February 2019, planned to be completed in three years.

[13] The first documented Sumatran rhinoceros was shot 16 km (9.9 mi) outside Fort Marlborough, near the west coast of Sumatra, in 1793.

Drawings of the animal, and a written description, were sent to the naturalist Joseph Banks, then president of the Royal Society of London, who published a paper on the specimen that year.

Unconfirmed reports suggest a small population may still survive in Myanmar, but the political situation in that country has prevented verification.

[35] Pairwise sequential Markovian coalescent (PSMC) analysis of a complete nuclear genome of a Sumatran specimen suggested strong fluctuations in population size, with a general trend of decline over the course of the Middle to Late Pleistocene with an estimated peak effective population size of 57,800 individuals 950,000 years ago, declining to around 500–1,300 individuals at the start of the Holocene, with a slight rebound during the Eemian Interglacial.

The Sumatran rhinoceros is fast and agile; it climbs mountains easily and comfortably traverses steep slopes and riverbanks.

[42] Remains of Sumatran rhinoceros have been found in Chinese Neolithic sites of Zhejiang, Henan, Fujian,[43] and the northeastern Tibetan Plateau.

[16] Conservation geneticists have recently begun to study the diversity of the gene pool within these populations by identifying microsatellite loci.

[49] On 2 October 2013, video images made with camera traps showing the Sumatran rhino in Kutai Barat, Kalimantan, were released by the World Wildlife Fund.

In the rainy season, they move to higher elevations; in the cooler months, they return to lower areas in their range.

The whistle-blow is the loudest of the vocalizations, loud enough to make the iron bars in the zoo enclosure where the rhinos were studied vibrate.

[2][7] The species is classed as critically endangered (primarily due to illegal poaching) while the last survey in 2008 estimated that around 250 individuals survived.

[2] The rainforests of Indonesia and Malaysia, which the Sumatran rhino inhabits, are also targets for legal and illegal logging because of the desirability of their hardwoods.

Although the hardwoods in the rainforests of the Sumatran rhino are destined for international markets and not widely used in domestic construction, the number of logging permits for these woods has increased dramatically because of the tsunami.

[45] However, while this species has been suggested to be highly sensitive to habitat disturbance, apparently it is of little importance compared to hunting, as it can withstand more or less any forest condition.

[39] Despite the species' persistent lack of reproductive success, in the early 1980s, some conservation organizations began a captive-breeding program for the Sumatran rhinoceros.

After years of failed attempts, the cow from Los Angeles, Emi, became pregnant for the sixth time, with the zoo's bull Ipuh.

Reproductive physiologist at the Cincinnati Zoo, Terri Roth, had learned from previous failures, though, and with the aid of special hormone treatments, Emi gave birth to a healthy male calf named Andalas (an Indonesian literary word for Sumatra) in September 2001.

[82] On 29 April 2007, Emi gave birth a third time, to her second male calf, named Harapan (Indonesian for "hope") or Harry.

[66][83] In 2007, Andalas, who had been living at the Los Angeles Zoo, was returned to Sumatra to take part in breeding programs with healthy females,[64][84] leading to the siring and 23 June 2012 birth of male calf Andatu, the fourth captive-born calf of the era; Andalas had been mated with Ratu, a wild-born cow living in the Rhino Sanctuary at Way Kambas National Park.

[98] In Indonesian East Kalimantan, only one old (estimated to be 35 to 40 years old) female named Pahu lives in Sumatran Rhino Sanctuary (SRS) Kelian, West Kutai after being captured in 2018, another identified is Pari, a female who lives in the wild in Sungai Ratah-Sungai Nyuatan-Sungai Lawa protected forest.

[99] Aside from those few individuals kept in zoos and pictured in books, the Sumatran rhinoceros has remained little known, overshadowed by the more common Indian, black and white rhinos.

Recently, however, video footage of the Sumatran rhinoceros in its native habitat and in breeding centers has been featured in several nature documentaries.

[100][101] Though they were documented by droppings and tracks, pictures of the Bornean rhinoceros were first taken and widely distributed by modern conservationists in April 2006, when camera traps photographed a healthy adult in the jungles of Sabah in Malaysian Borneo.

The night-time footage showed the rhino eating, peering through jungle foliage, and sniffing the film equipment.

The World Wildlife Fund, which took the video, has used it in efforts to convince local governments to turn the area into a rhino conservation zone.

There was also a Burmese belief that the best time to hunt was every July, when the Sumatran rhinos would congregate beneath the full moon.

In Borneo, the rhino was said to have a strange carnivorous practice: after defecating in a stream, it would turn around and eat fish that had been stupefied by the excrement.