The White Rhinoceros or square-lipped rhinoceros (Ceratotherium simum) is the largest and most numerous species of rhinoceros that exists. It has a wide mouth used for grazing and is the most social of all rhino species. The white rhinoceros consists of two subspecies: the southern white rhinoceros, with an estimated 17,460 wild-living animals at the end of 2007 (IUCN 2008), and the much rarer northern white rhinoceros. The northern subspecies has very few remaining, with seven confirmed individuals left, with only four still able to reproduce (Including those in captivity).
The white rhinoceros is the largest of the five species of rhinoceros and the world's largest land mammal after the three species of elephant. It has a massive body and large head, a short neck and broad chest. The head and body length is 3.7 to 4 m (12 to 13 ft) in males and 3.4 to 3.65 m (11.2 to 12.0 ft) in females, with the tail adding another 70 cm (28 in) and the shoulder height is 1.7 to 1.85 m (5 ft 7 in to 6 ft 1 in) in the male and 1.6 to 1.77 m (5 ft 3 in to 5 ft 10 in) in the female. Weight in this animal typically ranges from 1,360 to 3,630 kg (3,000 to 8,000 lb). The male, averaging 2,300 kg (5,100 lb) is heavier than the female, at an average of 1,700 kg (3,700 lb). The largest recorded white rhinoceros was about 4,500 kg (9,900 lb). On its snout it has two horn-like growths, one behind the other. These are made of solid keratin, in which they differ from the horns of bovids (cattle and their relatives), which are keratin with a bony core, and deer antlers, which are solid bone. The front horn is larger and averages 90 cm (35 in) in length, reaching as much as 150 cm (59 in). The white rhinoceros also has a noticeable hump on the back of its neck. Each of the four stumpy feet has three toes. The color of the body ranges from yellowish brown to slate grey. Its only hair is the ear fringes and tail bristles. White rhinos have a distinctive broad, straight mouth which is used for grazing. Its ears can move independently to pick up sounds but it depends most of all on smell. The olfactory passages which are responsible for smell are larger than their entire brain. The white rhinoceros has the widest set nostrils of any land based animal.
The southern subspecies or majority of White rhino live in southern Africa. About 98.5% of white rhino occur in just five countries (South Africa, Namibia, Zimbabwe, Kenya and Uganda). Almost at the edge of extinction in the early 20th century, the southern subspecies has made a tremendous comeback. In 2001 it was estimated that there were 11,670 white rhinos in the wild with a further 777 in captivity worldwide, making it the most common Rhino in the world. By the end of 2007 wild-living southern white rhino had increased to an estimated 17,480 animals (IUCN 2008).
White rhinoceroses live in crashes or herds of up to 14 animals (usually mostly female). Sub-adult males will congregate, often in association with an adult female. Most adult bulls are solitary. Dominant bulls mark their territory with excrement and urine. The dung is laid in well defined piles. It may have 20 to 30 of these piles to alert passing rhinoceroses that it is his territory. Another way of marking their territory is wiping their horns on bushes or the ground and scrapes with its feet before urine spraying. They do this around 10 times an hour while patrolling territory. The same ritual as urine marking except without spraying is also commonly used. The territorial male will scrape-mark every 30 m (98 ft) or so around its territory boundary. Subordinate males do not mark territory. The most serious fights break out over mating rights to do with a female. Female territory is overlapped extensively and they do not defend it.
- Shelter: Grass Umbrella, Large Stable, Small Stable
- Enrichment: Elephant Tree, Salt Lick
- Animal Food: Grass, Hay