Black Rhinoceros

The black rhinoceros (Diceros bicornis), also known as hook-lipped rhinoceros, is the smaller of two species of rhinoceros in Africa. The other being the white or square-lipped rhinoceros (Ceratotherium simum). The black rhinoceros is actually not black in coloration, and all species of rhinoceros are typically greyish in color. The name comes from the misinterpretation of the Dutch word used to describe the white rhinoceros, “wijd”, which means “wide” and describes the wide lip of the white rhinoceros. The word “wijd” was interpreted by the British to mean “white”, and the black rhinoceros, being the other rhinoceros species, was then simply referred to as black. Hook-lipped rhinoceros is a more descriptive name for the species and makes it easier to distinguish it from the white or square lipped rhinoceros.

An adult black rhinoceros will get to a height of 132-180 cm (52-72 in) at the shoulder and can reach lengths of 3.8 m (12.5 feet). Males are typically larger than females and a normal weight for an adult is between 800-1,400 kg (1,800-3,100 lb.), though unusually large males have reached twice that size. Both sexes have two horns growing from their skull, which are made of keratin, the same as our hair and fingernails. The front horn is typically larger, though some specimens have exceptionally large second horns. Average horn length is 50 cm (20 in), but there are records of horns up 140 cm (55 in).

The black rhinoceros is generally a solitary animal, except when females have calves. Young adults will sometimes seek out older individuals upon reaching independence. They have home ranges that change in size depending on available resources, but they are not very territorial, and they commonly share a range with other rhinoceroses. They are browsers, which means they will feed on leaves, branches, bushes and fruit and will use their prehensile hooked lip to grab the food while feeding. They are very shy animals and are noticeably rarer than their larger cousin, the white rhinoceros. This is mostly because black rhinoceroses tend to prefer thick bush, shrubland and dense woodlands. Their thick skin protects them against these often quite thorny habitats.

Because of their solitary lives, males only know if a female is ready to mate by smelling her dung and urine. Dung is often deposited in special areas called middens, which are shared by all rhinoceroses in the area, even white rhinoceroses. This makes it possible for rhinoceroses to communicate with each other and to know which other individuals are present in the area. When a female ready to mate is found, a male might have to fend off other males through sparring. If he wins, he will stay with the female for a few days to a few weeks, while copulating several times as day. The gestation period is 15-16 months, and after a calf is born it will stay with its mother for 2-3 years, until she gets a second calf. Sexual maturity is reached at the age of 5-7 for females and 7-8 for males. In undisturbed habitats a black rhinoceros can live to become 35-50 years old.

The black rhinoceros used to be the most common species of rhinoceros, with probably several hundred thousand individuals on continental Africa around the year 1900. During the 20th century the numbers drastically dropped due to hunting and poaching, and in 2008, only 4,200 individuals were left, although this was an increase from an expected 2,400 individuals from four years prior. The numbers have continued to rise due to conservation efforts and reintroduction programs. The population is now believed to hold around 6,200 individuals. It is still listed as critically endangered on the IUCN Red List and continues to face the great threat of poaching. The subspecies Western black rhinoceros (D. bicornis longipes) was declared extinct in 2011.