Grass Rhinoceros

The white rhino is considered the most sociable of rhino species (11). Females can usually be seen with their most recent offspring, which they stay with until the next calf is born (12). Larger, temporary associations of 14 or more individuals can also occasionally be observed (5), with immature individuals typically grouping together, as do mothers without calves (12). Dominant males, however, are usually solitary and occupy smaller home ranges than females (5), marking their boundary by spreading dung, defecating on well-used dung-piles known as 'middens', spraying urine, dragging their feet and damaging plants with their horns (4). While the dominant male will tolerate females and sub-adult males within their territory, and will attempt to keep receptive females from leaving, any invading bull will quickly be confronted (5). However, fights are rare and confrontations usually consist only of slight horn butting, false charges, and other displays (4). Breeding occurs throughout the year. After the courtship and mating period, which lasts from one to three weeks, the female may leave the bull's territory. Gestation lasts around 16 months and the single calf is very active soon after birth (4). If threatened, the mother will stand guard over her young, but otherwise the infant usually runs ahead of its mother (12). Calves are weaned anywhere from one to two years after birth. The normal interval between calves is two to three years (13). Sexual maturity is reached around six years in females and 10 to 12 years in males (4). White rhinos are grazers, feeding on large quantities of grasses that they crop with their wide, square front lip (4) (5). Individuals also drink water from watering holes almost daily; although they can survive for four or five days without water when conditions are dry (12). All rhinoceroses have poor eyesight, but good hearing and a very good sense of smell, on which they depend (5) (12).

Many southern white rhino are now concentrated within protected areas such as fenced sanctuaries, conservancies, rhino conservation areas and intensive protection zones. Effective management strategies have resulted in surplus animals being translocated to set up new populations within and outside the species' former range. In a number of countries, populations are now managed by both the state and the private sector, increasing their long-term security. Selling limited sport hunting of surplus males, for example, attracts large revenues and powerful incentives for private sector conservation, and generates much needed funds to help pay the high cost of successfully monitoring, protecting and managing rhino. All rhino were listed on CITES Appendix I by 1977, prohibiting international commercial trade in the species and their products. Following the continued rise in numbers of the southern white rhinoceros subspecies, however, the South African population was downlisted in 1994 to Appendix II, but only for trade in live animals to 'approved and acceptable destinations' and for the (continued) export of hunting trophies (1). Domestic anti-trade measures and legislation were also implemented in the 1990s to help reduce illegal trade (1), and some game managers immobilise white rhinos and remove their horns to deter poachers (4). There are a number of regional and continental African rhino conservation initiatives that advise on or support effective conservation programmes. These include the IUCN SSC's African Rhino Specialist Group, the SADC Rhino Management and Rhino Recovery Groups, the Rhino and Elephant Security Group and the SADC Regional Programme for Rhino Conservation (15). Thanks to the concerted efforts of conservationists, researchers and concerned individuals, particularly in South Africa, southern white rhinos have recovered from just a single population of between 20 and 50 animals in 1895 to about 17,500 today, with an additional 750 animals in captive breeding institutions worldwide, and are now the most abundant kind of rhino in the world (1) (10) (13). Rescued from near extinction a century ago, this subspecies stands as one of the world's greatest conservation success stories (6). Nevertheless, poaching pressure remains an ever-present threat and, with 99% of all southern white rhinos occurring in only four countries, the subspecies is still vulnerable and we cannot become complacent about its conservation (8). Sadly, the outlook for the northern white rhino doesn't look so bright. The Garamba project had managed to conserve the population at about 30 rhinos from the late 1980's up to 2003, but an upsurge in poaching resulted in it declining to only 4 animals in 2006. The most recent surveys have failed to find any evidence of this subspecies in Garamba National Park. If the northern white rhino has now become extinct in the wild, its survival may now depend upon the successful breeding of the small number of rhinos held at Dvur Kralove Zoo in the Czech Republic (1).

Amongst the most charismatic and recognisable of Africa's mega-fauna (4), the white rhinoceros is the largest of the five rhinoceros species and one of the world's biggest land animals, second only to the African and Asian elephant in size (5) (6). Unlike its common name suggests, this enormous, virtually hairless mammal is not in fact white, but slate-grey to yellowish-brown in colour (5) (7). The 'white' likely comes from a mistranslation of the Afrikaner word for 'wide', referring to the animal's wide mouth (5). Indeed, this species is often called the 'square-lipped rhinoceros' because of its broad, square, rather than pointed, flexible upper lip, differentiating it from the black rhino (Diceros bicornis). The white rhinoceros can also be distinguished from its African cousin by its longer skull, less sharply defined forehead and more pronounced shoulder hump (7). Like the black rhinoceros and Sumatran rhinoceros, this species has two horns, the front being longer and averaging 60 cm in length, but occasionally reaching up to a enormous 1.5 m (5) (7).

Found in grassland and open savanna woodlands (1). White rhinos prefer flat lands with bush for cover, grass for grazing and water for drinking and wallowing in (5), and can occasionally be found in swampy regions (4).

Two geographically separated subspecies of white rhinoceros are recognised, the northern and the southern (1). Once ranging in large numbers throughout north-central Africa south of the Sahara (8), the northern subspecies is now amongst the rarest of all rhinos, occurring only in the Garamba National Park, Democratic Republic of Congo (DRC) (1), where as few as 4 animals were counted during intensive surveys in 2006 (9). Meanwhile, the southern subspecies is the most numerous of all the world's rhinos, with its stronghold in South Africa (93%) (10). Much smaller populations exist following reintroductions within the subspecies' former range in Botswana, Namibia, Swaziland and Zimbabwe and introduced outside their historical range in Zambia, Uganda and Kenya (1) (5) (11).

Classified as Near Threatened (NT) on the IUCN Red List (1). Two subspecies of the white rhinoceros are recognised: northern (C. s. cottoni), and southern (C. s. simum). The northern white rhinoceros is classified as Critically Endangered (CR) on the IUCN Red List and listed on Appendix I of CITES; the southern white rhinoceros is classified as Near Threatened (NT) on the IUCN Red List and listed on Appendix I of CITES, except in South Africa and Swaziland, where it is listed on Appendix II (1) (3).

The decline of Africa's rhinos is one of the greatest wildlife tragedies of our time (6). Like its African cousin, the black rhinoceros, the white rhinoceros has suffered from habitat loss and poaching for the international rhino horn trade (1) (5). Rhino horn has two main markets; it is sold to Asian countries, particularly China, Taiwan and South Korea, for use in traditional medicine, and it is sold to Middle Eastern countries such as Yemen and Oman, which consider horn a prized material with which to make ornately carved handles for ceremonial daggers (jamiyas) (1) (5) (6). The situation has only been exacerbated for the northern subspecies by civil war, civil unrest and poverty in both the DRC and neighbouring Sudan, which has weakened any conservation efforts (1) (6). The northern white rhino was once widespread, with an estimated 2,250 individuals across five African states in 1960. In the ensuing years, however, poaching devastated populations to the point that, by 1984, numbers had fallen to a mere 15 animals, all restricted to the DRC's Garamba National Park (14). Habitat destruction and urbanisation have also affected white rhino populations (4).