Sumatran rhinoceros
- Female Sumatran rhinos in captivity often die due to male aggression, unlike in the wild, where they can escape. In captivity, male aggression usually leads to fatal outcomes.
- The Sumatran rhinoceros (badak) is the smallest and hairiest rhino, the only Asian with two horns.
- The Sumatran rhino is the smallest rhinoceros among rhinoceroses, standing 112–145 cm at the shoulder, with an adult weight of 600–950 kg. Its nasal horn reaches 15–25 cm in length, while the second horn is underdeveloped.
- The Sumatran rhino is fast and agile, easily overcoming mountain slopes and riverbanks. Its lifespan in the wild is 30–45 years.
- A female northern Sumatran rhino lived 32 years and 8 months in captivity, a record age. She died in the London Zoo in 1900.
- Sumatran rhino calves always stay close to their mother to avoid attacks. Tigers and dogs can kill young individuals, but this occurs very rarely.
- The female is an induced ovulator: without mating she becomes infertile.
- Female Sumatran rhinos reach sexual maturity at 6–7 years, males at 20 years. Their pregnancy lasts about 15–16 months.
- Solitary and mainly nocturnal.
- Feeds on leaves and shoots of more than 100 plant species.
Age
The Sumatran rhinoceros, also known as the Asiatic two-horned rhinoceros or hairy rhino, has a typical lifespan of from 30 to 45 years, although the maximum recorded lifespan was 32 years and 10 months, with a theoretical lifespan ranging from 23 years and 5 months to 30 years and 1 month. The species reaches sexual maturity at an age between 5 and 12 years. A Sumatran rhino’s young are born with their eyes open and begin walking immediately. The embryo develops inside the mother for approximately 16 months. The young lives with its mother, drinks milk, and gradually begins to eat plants. An adult animal lives independently and can produce offspring, a stage lasting from 7 to 45 years.
Phenotype
Calf: Hair color—Thick reddish fur covers almost the entire body and protects from insects. Calf: Number of horns—Two small horns begin to grow shortly after birth. Adult: Number of anterior horns—The anterior horn helps in defense and breaking branches for food. Adult: Hair color—Sparse, coarse fur remains only on the ears and tail. Adult: Number of posterior horns—The posterior horn is small and almost invisible. Adult: Skin color—Thick skin with deep folds protects the body.
Physiology
The Sumatran rhinoceros, also known as the Asiatic two-horned rhinoceros or hairy rhino, has a body height ranging from 17.8 centimeters to 4.5 meters and a body length varying from 2.5 to 3.2 meters; its mass ranges from 1.74 to 1.75 metric tons. The embryo stage has a body mass from 0 grams to 40 kilograms, while the young have a body mass from 40 to 200 kilograms and a body length from 80 centimeters to 1.4 meters. An adult individual's body mass is from 0.5 to 0.8 metric tons, with a body length also ranging from 2.5 to 3.2 meters.
Habitat
The Sumatran rhinoceros inhabits tropical moist forests, always hot and humid, with large trees and vines, and lives on land and within forested areas. The species’ elevation ranges from 200 meters to 2 kilometers above sea level. The climate is consistently hot and wet throughout the year, with frequent rainfall and high humidity; it is also consistently very wet with rain occurring almost constantly and a very humid environment, although periods of dryness can occur.
Shelter
The badger inhabits forests near water and does not have a permanent or long-term shelter; the species uses branches and bark for protection from insects, resting, and sun protection.
Geography
The Sumatran rhinoceros occupies the Indomalaya, Neotropical, and Palearctic biogeographical realms. The species is found in subtropical evergreen forests of the Yunnan Plateau ecosystem.
Feeding
The Sumatran rhinoceros feeds exclusively on plants, consuming leaves, young shoots, fruits, and tree bark. The species obtains food by plucking vegetation with its lips and breaking branches with its horn, utilizing leaves, shoots, fruits, bark, branches, young shoots, sprouts, fruits, and wood as nourishment. The feeding strategy involves searching for and acquiring food. Young Sumatran rhinoceroses consume milk. Daily food intake ranges from 20 kilograms to 50 kilograms.
Reproduction
The Sumatran rhinoceros, also known as the Asiatic two-horned rhinoceros or hairy rhino, inhabits terrestrial environments and does not live near bodies of water. The species reproduces through viviparity, meaning the young are born alive on land, rather than hatching from eggs or larvae. Gestation lasts 15–16 months, and the female gives birth to a single offspring. The young remains with its mother for two or three years. The female reaches maturity between 7 and 12 years of age and has one offspring per litter. The interval between reproductive events is from 3 to 5 years. Embryonic development takes 8 months, and the size of a litter is 1. Reproduction always occurs through homogamy, involving fertilization without generational changes.