Sumatran Rhinoceros

Sumatran Rhinoceros

Sumatran rhino, Hairy rhinoceros, Asian two-horned rhinoceros

Dicerorhinus sumatrensis
Population size
Bnelow 80
Life Span
30-45 years
Top speed
km/h mph 
kg lbs 
cm inch 
m ft 

The Sumatran rhinoceros (Dicerorhinus sumatrensis) is a rare member of the family Rhinocerotidae and one of five extant species of rhinoceros. It is now critically endangered, with only five substantial populations in the wild. Sumatran rhinos, along with the Javan rhino, are the most threatened rhino species. Sumatran rhinos outnumber Javan rhinos but are more under threat by poaching. They were declared extinct in Malaysia in the wild in 2015.


A Sumatran rhinoceros is the smallest among the living rhinos. Its shaggy appearance is its best-known feature, due to the long, coarse hair covering much of its body. As it grows older, this hair falls out, meaning that its age can, to a certain extent, be determined by how hairy it is. Underneath, its hide has a red undertone, making this rhino unique in appearance. Its hairiness suggests to many scientists that it may be a direct descendant of the woolly rhinoceros, extinct for about 10,000 years. Like the two African species, it has two horns. The larger is the nasal horn, typically only 15-25 cm (5.9-9.8 in). The posterior horn is much smaller, usually less than 10 cm (3.9 in) long, and often little more than a knob. The larger nasal horn is also known as the anterior horn; the smaller posterior horn is known as the frontal horn. The horns are dark grey or black in color. The bulls have larger horns than the cows. Sumatran rhinos have a patch of long hair around their ears and a thick clump of hair at the end of their tail. Like all rhinos, they have very poor vision.




Biogeographical realms

The Sumatran rhinoceros once enjoyed a continuous range north to Burma, Bangladesh, and eastern India. It may also have lived in Cambodia, Vietnam, and Laos. It is now only reported to occur in Peninsular Malaysia, Sabah, Borneo, and the island of Sumatra. Some conservationists hope they still survive in Burma, though this is considered unlikely. It lives in lowland and highland secondary rainforests, cloud forests, and swamps, in hilly areas with water nearby, particularly steep upper valleys that have copious undergrowth.

Sumatran Rhinoceros habitat map

Climate zones

Sumatran Rhinoceros habitat map
Sumatran Rhinoceros
Public Domain Dedication (CC0)

Habits and Lifestyle

Sumatran rhinos are solitary animals. Males and females both maintain home ranges, which overlap. Males have larger territories than females. When rhinos do meet on occasion, they do not remain together for very long. These animals are well-known for their marking behavior, marking their trails with urine, feces, and soil scraps, which act as olfactory and visual signals for passing rhinos. Sumatran rhinos are inexhaustible walkers. They are fast and agile; they climb mountains easily and comfortably traverse steep slopes and riverbanks. They eat before dawn and again before sunset, moving mostly by night. In the daytime, they are often found in ponds of rainwater or wallows dug out near streams. Sumatran rhinos also make patterned seasonal movements, traveling along hills at the time when the lowlands are flooded, and descending during times of cool and relatively dry weather, returning to the high ground to avoid summer insects, in particular, horse flies.

Seasonal behavior

Diet and Nutrition

Sumatran rhinos are herbivores (folivore, lignivore), eating leaves, young saplings, twigs, shoots, and plants in secondary growth. They also visit salt licks, very important to the nutrition of rhinos. These licks can be small hot springs, seepages of salty water, or mud-volcanoes.

Mating Habits

15-16 months
1 calf
2-3 years

Sumatran rhinos are polygynous, with each male mating with multiple females during a breeding season. The breeding period is not known. However, most births take place between October and May, which is when the heaviest rainfall occurs. Gestation is thought to be between 15 to 16 months, with the interval between births being at least 3-4 years. A single calf is born, and during the first few days is hidden amongst dense vegetation near a salt lick while its mother browses. When it is about 2 months old, it wanders near its mother. During the first stages of development, calves may associate with each other, but later they become solitary. Weaning occurs at 16-17 months old and calves stay with their mother until they are 2 or 3 years old. Young females become reproductively mature at the age of 6 to 7 years, while males start to breed when they are about 10 years old.


Population threats

Hunting has been a primary factor in the decline of this species. Rhino horn and other body parts have been used for centuries in traditional Asian medicine to treat fevers, strokes, and other ailments. Hunting is now illegal, but poaching continues, with these animals still being killed for their horns. The other main threat is the loss of habitat due to logging and the conversion of land for other uses. As suitable habitats become fewer, rhino populations are forced into small, fragmented subpopulations, possibly too small to form a viable group. Left in the remaining pockets of forest, these animals become even more vulnerable to disease, poaching, and environmental disasters.

Population number

According to the IUCN Red List, the total Sumatran rhino population size is fewer than 80 individuals. Currently, the species is classified as Critically Endangered (CR) and its numbers today continue to decrease.

Fun Facts for Kids

  • Sumatran rhinos like mud. Wallowing cools them and the mud prevents their skin from drying and cracking.
  • Sumatran rhinos can swim well.
  • This species is the most vocal out of the rhinoceros species. Rhino makes three distinct types of noises: eeps, whistle blows, and whales.
  • The first rhinoceroses were on Earth around 50 million years ago. Some of them, like the woolly rhino, with a thick coat of curls, looked somewhat different than today’s rhinos.
  • The horns of the majority of animals are mainly bone inside a thin envelope made of keratin. A rhino's horn is made completely of keratin, the same protein substance that human hair and fingernails are made of.
  • Sumatran rhinos can eat over 50 kg (110 lb) of food every day.

Coloring Pages


1. Sumatran Rhinoceros Wikipedia article -
2. Sumatran Rhinoceros on The IUCN Red List site -

More Fascinating Animals to Learn About