Formerly, during the 19th century, in two separate regions of Africa: 1) Southern Chad, Central African Republic, southwest Sudan, northeast Zaire, and northwest Uganda; 2) southeast Angola, portions of Mozambique, Zimbabwe, Botswana, eastern Namibia, and northeast South Africa. Current range a mere fragment of this and restricted to game preserves and national parks.
Biogeographic Regions: ethiopian (Native )
Two subspecies of White Rhinoceros are currently recognized, the northern and the southern, each having a strikingly discontinuous range. The Northern White Rhino used to range over parts of north-western Uganda, southern Chad, south-western Sudan, the eastern part of Central African Republic, and north-eastern Democratic Republic of the Congo (Sydney 1965). The previous only confirmed population in Garamba National Park in north-eastern Democratic Republic of the Congo is now considered probably extinct as despite systematic ground surveys over probable range and additional foot patrols and aerial reconnaissance no live rhinos have been seen since 2006 and no fresh sign since 2007. There have been unconfirmed reports of rhino in southern Sudan, and surveys are planned. The last four potential breeding Northern White Rhino in captivity in Dvur Kralove Zoo in the Czech Republic have been translocated to a private conservancy in Kenya in the hope this will stimulate their breeding. These animals form the only current confirmed population.
While Kenya has not been a White Rhino range state in the last two hundred years; evidence from fossils and cave paintings in Kenya and northern Tanzania suggests that the White Rhinoceros, presumably similar to the northern race (C. s. cottoni), was widespread and a part of the East African savanna fauna until 3,000 years ago or less (M. Leakey pers. comm.), when it was probably displaced by pastoralists who could easily kill such tame animals (Brett RA [ed] 1993). This is based on the White Rhino subfossil documented by Maeve Leakey from 3,000 year from Rift Valley (Lake Nakuru area). Thus at one stage Kenya was once a White Rhino range state (subspecies unknown) and hence the White Rhino as a species but not C. s. simum as a subspecies has probably been reintroduced to Kenya (with the latter being an introduction of a probable out of range subspecies). A recent report of a white rhino hunting trophy from Kenya in an Austrian Museum still has to be confirmed but merits further investigation.
Note: At the request of certain members and countries, the IUCN SSC African Rhino Specialist Group (AfRSG) has a policy of not releasing detailed information on the whereabouts of all rhino populations for security reasons. For this reason, only whole countries are shaded on the map.
Head and body length= 335-420 cm with a tail of 50-70 cm. Shoulder height= 150-185 cm. Males are larger than females. White rhinos are among the largest living land animals. They are usually light gray to dark yellow. They have very little hair, with a small amount being found on the tips of their tails and ears and intermittently scattered on their bodies. They have two horns; the front horn is longer and often attains a length of 150 cm. The head is very long and there may be a large hump on the neck. The ears are long, and they seem to pivot freely. White rhinos lack canines and incisors and have a wide (20 cm) flexible front lip.
Range mass: 1440 to 3600 kg.
Other Physical Features: endothermic ; bilateral symmetry
Primarily open woodland with nearby open grassland, thick brush, and water. White rhinos prefer flat lands and can occasionally be found in swampy regions.
Terrestrial Biomes: savanna or grassland ; chaparral ; forest
Habitat and Ecology
White rhinos are grazers, feeding on grasses that they crop with their wide front lip. Their short legs, long head reaching almost to the ground, and wide mouth are used in combination with a side to side head movement to eat massive quantities of grass.
Life History and Behavior
Perception Channels: tactile ; chemical
Status: wild: 45.0 years.
Status: wild: 50.0 years.
Status: wild: 36.0 years.
Lifespan, longevity, and ageing
Breeding occurs throughout the year with two peak periods in summer and fall. During breeding, the dominant, usually solitary, males stay with a receptive female from 1-3 weeks. During this courtship, the pair often chases, clash horns, and vocalize with each other. After mating, the female leaves the bull's territory. The gestation period is around 16 months. The single young weighs around 50 kg and is very active soon after birth. Calves are weaned anywhere from 1-2 years after birth. After about 2-3 years, the female drives the calf away and mates again. Sexual maturity is reached around 6 years in females and 10-12 years in males.
Key Reproductive Features: gonochoric/gonochoristic/dioecious (sexes separate); sexual
Average birth mass: 52500 g.
Average gestation period: 515 days.
Average number of offspring: 1.
Average age at sexual or reproductive maturity (male)
Sex: male: 1643 days.
Average age at sexual or reproductive maturity (female)
Sex: female: 1643 days.
Molecular Biology and Genetics
Barcode data: Ceratotherium simum
Below is a sequence of the barcode region Cytochrome oxidase subunit 1 (COI or COX1) from a member of the species.
See the BOLD taxonomy browser for more complete information about this specimen and other sequences.
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Download FASTA File
Statistics of barcoding coverage: Ceratotherium simum
Public Records: 2
Specimens with Barcodes: 4
Species With Barcodes: 1
The white rhino is one of the most charismatic, recognizable, and widely studied endangered animals. Poachers have long sought the white rhino for its horn, which in some cultures is thought to have medicinal affects. Recent habitat destruction and urbanization have also affected white rhino populations. Droughts affect their numbers by killing the plants on which they browse. Since white rhinos do not have a large home range, a widescale drought can be devastating. Political disruptions in some African countries have weakened many conservation efforts. The white rhino is listed by the IUCN and all other conservation groups as endangered. Many game wardens and researchers routinely risk their lives to help protect this species from poachers. New and innovative management programs are being developed to help save this magnificent creature. Just over 4000 white rhinos exist in the wild today.
IUCN Red List of Threatened Species: near threatened
IUCN Red List Assessment
Red List Category
Red List Criteria
- 2011Near Threatened
- 2003Near Threatened(IUCN 2003)
- 2003Near Threatened
- 2002Near Threatened
- 1994Vulnerable(Groombridge 1994)
As of 31 December 2010, there were an estimated 20,170 White Rhino in the wild (see Table 1 in the attached pdf). As of Dec 2008 there were an estimated 750 in captivity worldwide. The majority (98.8%) of White Rhino occur in just four countries (South Africa, Namibia, Zimbabwe and Kenya) (AfRSG data 2011).
Once widespread in the bushveld areas of southern Africa south of the Zambezi river, the Southern White Rhino was on the brink of extinction by the end of the 19th century having been reduced to just one small population of approximately 20-50 animals in KwaZulu-Natal, South Africa. However, by the end of 2010, after years of protection and many translocations, the subspecies has grown to 20,160 wild animals. South Africa remains the stronghold for this subspecies (93.2%) conserving 18,800 individuals in 2010. Smaller reintroduced populations occur within former range states in Botswana, Namibia, Swaziland, and Zimbabwe; populations of free-ranging Southern White Rhino have also been established outside their historical range in Kenya, Zambia (Emslie and Brooks 1999) and more recently Uganda although Uganda is a former C. s. cottoni range state and an ~3,500 year old White Rhino subfossil indicates at one stage Kenya was also once a white rhino range state. Numbers of White Rhino under private ownership continue to increase, numbering at least 5,500 in 429+ populations by the end of 2010. The bulk of White Rhino (14,529 or 72.1%) continue to be conserved on state land. In 2007 Namibia, Zimbabwe and Kenya were the only other countries with over 300 wild Southern White Rhino, but following increased poaching numbers in Zimbabwe had dropped to 290 by the end of 2010. Together these three countries conserve 82.1% of the subspecies outside of South Africa.
In the only confirmed surviving wild population in Garamba National Park, Democratic Republic of the Congo, Northern White Rhino (C. s. cottoni) numbers declined rapidly from 30 in April 2003 due to an upsurge in poaching, and surveys in 2006 confirmed the presence of only four rhinos (Emslie et al. 2006). Numbers are believed to have stood at around 2,360 in 1960 (Emslie and Brooks 1999). However based largely on extensive and systematic foot surveys which failed to sight live rhino and find any signs (spoor and dung) this population is now considered probably extinct. Reports of a few possible Northern White Rhino surviving in a remote part of Southern Sudan have yet to be confirmed although surveys are planned. The last four potential breeding Northern White Rhino in captivity have been moved to a private conservancy in Kenya in the hope that a move to more wild conditions will stimulate them to breed.
One of the main threats to the population is illegal hunting (poaching) for the international rhino horn trade. Rhino horn has two main uses: traditional use in Chinese medicine, and ornamental use (for example, rhino horn is a highly prized material for making ornately carved handles for ceremonial daggers (jambiyas) worn in some Middle East countries). Until recently, at the continental species level, poaching of White Rhinos has not had a serious impact on overall numbers of White Rhinos in Africa, with poaching losses in parts of the range being surpassed by encouraging growth rates in others. From detected and reported figures, the annual average poaching incidents during 2003 to 2005 represented just 0.2 % of the total number of White Rhinos at the end of 2005 (Emslie et al. 2007). However poaching levels have increased dramatically in recent years (Milliken et al. 2009).
However poaching has escalatated dramatically in recent years in South Africa, Zimbabwe and Kenya in response to significant increases in black market prices for horn. For example the total numbers of rhinos poached annually in the major range state South Africa has increased from 13, to 83, 122, 333 and 448 over the period 2007-2011. At the time of writing the rate of poached has continued to increase in 2012 with projections of the numbers poached in South Africa could reach 600 by the end of 2012. While still less than the net growth in numbers due to breeding the continued escalation in poaching threatens to soon reverse the gains achieved if it cannot be stalled or reversed. If current trends continue numbers in South Africa could start to decline by 2016. As a proportion of total numbers poaching levels in the major range states have been highest in Zimbabwe. As described above the significantly increased and escalating poaching, increased protection costs, declining live sale prices and reduced incentives are leading to increasing numbers of private owners in South Africa seeking to get rid of their rhino. If this worrying trend continues this threatens to reverse the expansion of range and has the potential to also significantly reduce conservation budgets (due to declining live sales).
Poaching and civil wars in both Democratic Republic of the Congo and neighbouring Sudan have had a devastating impact on Northern White Rhino. Whilst poaching pressure initially increased during civil unrest and war in the late 1990s, good reproduction enabled the population to remain relatively stable. However, since 2003, poaching escalated and the population declined rapidly with 11 carcasses found in a three-month period between March and May 2004. Confirmed numbers of Northern White Rhino fell from 30 individuals in April 2003 to just four in August 2005. No live rhino have been seen since 2006 or signs of live rhino (spoor or dung) reported since 2007 despite intensive systematic foot surveys. It is believed that the Northern White Rhino has probably gone extinct in the Democratic Republic of the Congo.
Effective field protection of rhino populations has been critical. Many remaining rhino are now concentrated in fenced sanctuaries, conservancies, rhino conservation areas and intensive protection zones where law enforcement effort can be concentrated at effective levels. Monitoring has also provided information to guide biological management decision-making aimed at managing rhino populations for rapid population growth. This has resulted in surplus animals being translocated to set up new populations both within and outside the species’ former ranger. However increasing black market prices for rhino horn, and increased poaching of rhino and involvement of criminal syndicates in recent years pose a significant threat to rhino populations. Increasing efforts are also being made to integrate local communities into conservation efforts. Strategically, White Rhinos are now managed by a range of different stakeholders (private sector and state) in a number of countries increasing their long-term security. In Southern Africa live sale of White Rhinos on auction (and limited sport hunting of surplus males) has also created incentives for private sector conservation and generated much needed funds which can help pay the high cost of successfully monitoring, protecting and managing rhino. Over 5,500 White Rhino across Africa are now managed by the private sector throughout Africa with the majority in South Africa (AfRSG 2011). However as discussed above incentives are declining while protection costs and risks have increased resulting in increased numbers of South African owners looking to get rid of their white rhino.
By 1977, all African rhino species were listed on CITES Appendix I, and all international commercial trade in rhinos and their products was prohibited. However, following a continued increase in numbers, the South African population of Southern White Rhino 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. Numbers have almost trebled since then. In 2004, Swaziland’s Southern White Rhino were also downlisted to CITES Appendix II, but only for live export and for limited export of hunting trophies according to specified annual quotas. To help reduce illegal trade, and complement CITES international trade bans, domestic anti-trade measures and legislation were implemented in the 1990s by a number of the major consumer states and law enforcement effort has been stepped up in many consumer countries. In addition to local, national, international and continental initiatives, there are a number of regional African rhino conservation initiatives: the South African Development Community (SADC) Rhino Management Group , recently formed East African Rhino Management Group and the Southern African Rhino and Elephant Security Group/Interpol Environmental Crime Working Group. IUCN SSC African Rhino Specialist Group is the continental coordinating body for rhino conservation in Africa.
Relevance to Humans and Ecosystems
Although not beneficial, white rhino horns are valued at thousands of dollars on the black market. The white rhino also is a very large draw at zoos across the world and for tourists who come to many poor African countries just to get a glimpse to this animal.
The white rhinoceros or square-lipped rhinoceros (Ceratotherium simum) is the largest 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 five confirmed individuals left, with only four still able to reproduce (Including those in captivity).
A popular theory of the origins of the name "white rhinoceros" is a mistranslation from Dutch to English. The English word "white" is said to have been derived by mistranslation of the Dutch word "wijd", which means "wide" in English. The word "wide" refers to the width of the rhinoceros' mouth. So early English-speaking settlers in South Africa misinterpreted the "wijd" for "white" and the rhino with the wide mouth ended up being called the white rhino and the other one, with the narrow pointed mouth, was called the black rhinoceros. Ironically, Dutch (and Afrikaans) later used a calque of the English word, and now also call it a white rhino. This suggests the origin of the word was before codification by Dutch writers. A review of Dutch and Afrikaans literature about the rhinoceros has failed to produce any evidence that the word wijd was ever used to describe the rhino outside of oral use. Other popular theories suggest the name comes from its wide appearance throughout Africa, its color due to wallowing in calcareous soil or bird droppings or because of the lighter colour of its horn.
An alternative name for the white rhinoceros, more accurate but rarely used, is the square-lipped rhinoceros. The white rhinoceros' generic name, Ceratotherium, given by the zoologist John Edward Gray in 1868, is derived from the Greek terms keras (κερας) "horn" and therion (θηριον) "beast". Simum, is derived from the Greek term simus (σιμος), meaning "flat nosed".
Taxonomy and evolution
The white rhinoceros of today was said to be likely descended from Ceratotherium praecox which lived around 7 million years ago. Remains of this white rhino have been found at Langebaanweg near Cape Town. A review of fossil rhinos in Africa by Denis Geraads has however suggested that the species from Langebaanweg is of the genus Ceratotherium, but not Ceratotherium praecox as the type specimen of Ceratotherium praecox should, in fact, be Diceros praecox, as it shows closer affinities with the black rhinoceros Diceros bicornis. It has been suggested that the modern white rhino has a longer skull than Ceratotherium praecox to facilitate consumption of shorter grasses which resulted from the long term trend to drier conditions in Africa. However, if Ceratotherium praecox is in fact Diceros praecox, then the shorter skull could indicate a browsing species. Teeth of fossils assigned to Ceratotherium found at Makapansgat in South Africa were analysed for carbon isotopes and the researchers concluded that these animals consumed more than 30% browse in their diet, suggesting that these are not the fossils of the extant Ceratotherium simum which only eats grass. It is suggested that the real lineage of the white rhino should be; Ceratotherium neumayri → Ceratotherium mauritanicum → C. simum with the Langebaanweg rhinos being Ceratotherium sp. (as yet unnamed), with black rhinos being descended from C. neumayri via Diceros praecox.
Recently, an alternative scenario has been proposed under which the earliest African Ceratotherium is considered to be Ceratotherium efficax, known from the Late Pliocene of Ethiopia and the Early Pleistocene of Tanzania. This species is proposed to have been diversified into the Middle Pleistocene species C. mauritanicum in northern Africa, C. germanoafricanum in East Africa, and the extant C. simum. The first two of these are extinct, however, C. germanoafricanum is very similar to C. simum and has often been considered a fossil and ancestral subspecies to the latter. The study also doubts the ancestry of C. neumayri from the Miocene of southern Europe to the African species. It is likely that the ancestor of both the Black and the White rhinos was a mixed feeder, with the two lineages then specialising in browse and graze, respectively.
Southern white rhinoceros
There are two subspecies of white rhinos; the southern white rhinoceros (Ceratotherium simum simum) and the northern white rhinoceros. As of 31 December 2007, there were an estimated 17,460 southern white rhino in the wild (IUCN 2008), making them by far the most abundant subspecies of rhino in the world; the number of southern white rhinos outnumbers all other rhino species combined. South Africa is the stronghold for this subspecies (93.0%), conserving 16,255 individuals in the wild in 2007 (IUCN 2008). There are smaller reintroduced populations within the historical range of the species in Namibia, Botswana, Zimbabwe and Swaziland, while a small population survives in Mozambique. Populations have also been introduced outside of the former range of the species to Kenya, Uganda and Zambia.
Wild-caught southern whites will readily breed in captivity given appropriate amounts of space and food, as well as the presence of other female rhinos of breeding age. For instance, 91 calves have been born at the San Diego Zoo Safari Park since 1972. However, for reasons that are not currently understood, the rate of reproduction is extremely low among captive-born southern white females.
Northern white rhinoceros
The northern white rhinoceros, or northern square-lipped rhinoceros (Ceratotherium simum cottoni) is considered Critically Endangered or Extinct in the Wild. Formerly found in several countries in East and Central Africa south of the Sahara, this subspecies is a grazer in grasslands and savanna woodlands. In the world, there are currently only three rhinos of this subspecies left in captivity and three have been returned to a conservancy in Kenya.
Initially, six northern white rhinoceros lived in the Dvůr Králové Zoo in the Czech Republic. Four of the six rhinos (which are also the only reproductive animals of this subspecies) were transported to Ol Pejeta Conservancy in Kenya, Africa, where scientists hope they will successfully breed and save this subspecies from extinction. One of two remaining in the Czech Republic died in late May 2011. The two other rhinos presently live at the San Diego Zoo's Safari Park in California. One of the last two males capable of natural mating died on October 18, 2014.
Following the phylogenetic species concept, recent research has suggested the northern white rhinoceros may be an altogether different species, rather than a subspecies of white rhinoceros, in which case the correct scientific name for the former is Ceratotherium cottoni. Distinct morphological and genetic differences suggest the two proposed species have been separated for at least a million years.
The white rhinoceros is generally considered the largest land mammal after the elephants. Their bodies are massive and they have large heads, short necks and broad chests. The head and body length is 3.7 to 4 m (12.1 to 13.1 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 170 to 186 cm (5.58 to 6.10 ft) in the male and 160 to 177 cm (5.25 to 5.81 ft) in the female. 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 is usually around 60 cm (24 in) in length, sometimes reaching 150 cm (59 in) but only in females. 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.
Behavior and ecology
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White rhinoceroses are found in grassland and savannah habitat. Herbivore grazers that eat grass, preferring the shortest grains, the white rhinoceros is one of the largest pure grazers. It drinks twice a day if water is available, but if conditions are dry it can live four or five days without water. It spends about half of the day eating, one third resting, and the rest of the day doing various other things. White rhinoceroses, like all species of rhinoceros, love wallowing in mudholes to cool down. The white Rhinoceros is thought to have changed the structure and ecology of the savanna’s grasslands. Comparatively based on studies of the African elephant, scientist believe the white Rhino is a driving factor in the ecosystem it resides. The destruction of the megaherbivore could have serious cascading effects on the ecosystem and harm other animals.
White rhinoceroses produce sounds which include a panting contact call, grunts and snorts during courtship, squeals of distress, and deep bellows or growls when threatened. Threat displays (in males mostly) include wiping its horn on the ground and a head-low posture with ears back, combined with snarl threats and shrieking if attacked. The white rhinoceros is quick and agile and can run 50 km/h (31 mph).
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.
Females reach sexual maturity at 6–7 years of age while males reach sexual maturity between 10–12 years of age. Courtship is often a difficult affair. The male stays beyond the point where the female acts aggressively and will give out a call when approaching her. The male chases and or blocks the way of the female while squealing or wailing loudly if the female tries to leave his territory. When ready to mate the female curls her tail and gets into a stiff stance during the half hour copulation. Breeding pairs stay together between 5–20 days before they part their separate ways. Gestation occurs around 16–18 months. A single calf is born and usually weighs between 40 and 65 kg (88 and 143 lb). Calves are unsteady for their first 2 to 3 days of life. When threatened the baby will run in front of the mother, who is very protective of her calf and will fight for it vigorously. Weaning starts at 2 months, but the calf may continue suckling for over 12 months. The birth interval for the white rhino is between 2 and 3 years. Before giving birth the mother will chase off her current calf. White rhinos can live to be up to 40–50 years old. Adult white rhinos have no natural predators (other than humans) due to their size, and even young rhinos are rarely attacked or preyed on due to the mother's presence and their tough skin.
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).
The northern white rhino (Ceratotherium simum cottoni) formerly ranged over parts of north-western Uganda, southern Chad, south-western Sudan, the eastern part of Central African Republic, and north-eastern Democratic Republic of the Congo (DRC). The last surviving population of wild northern white rhinos are located in Garamba National Park, Democratic Republic of the Congo (DRC) but in August 2005, ground and aerial surveys conducted under the direction of African Parks Foundation and the African Rhino Specialist Group (ARSG) have only found four animals: a solitary adult male and a group of one adult male and two adult females. In June 2008 it was reported that the subspecies may have gone extinct in the wild.
Like the black rhino, the white rhino is under threat from habitat loss and poaching, most recently by Janjaweed. The horn is mostly used for traditional medicine although there are no health benefits from the horn; the horn is also used for traditional necklaces.
Rhino poaching has been occurring for well over four centuries, as hunters have driven the Indian rhinoceros to near-extinction ever since the colonial era. Millions of years before this, however, there were species of rhinoceros that grew up to twenty feet long. These exotic creatures were believed to become extinct due to human cause, citing the enormous impact people can have on the natural world. The 19th-century concept of hunting for sport nearly eradicated the white rhino from the planet, until anti-poaching laws in India and Nepal helped the species recover to a considerable extent. “Operation Rhino,” initiated in 1961, was a program designed to save the rhino from extinction. Remaining members of the species were moved to reserves in South Africa, but in 1970 it was revealed that the rhinoceros population has decreased by about 90% since historic times.
Historically the major factor in the decline of white rhinos was uncontrolled hunting in the colonial era, but now poaching for their horn is the primary threat. The white rhino is particularly vulnerable to hunting, because it is a large and relatively unaggressive animal and generally occurs in herds.
Despite the lack of scientific evidence, the rhino horn is highly prized in traditional Asian medicine, where it is ground into a fine powder or manufactured into tablets to be used as a treatment for a variety of illnesses such as nosebleeds, strokes, convulsions, and fevers. Due to this demand, several highly organized and very profitable international poaching syndicates came into being and would carry out their poaching missions with advanced technologies ranging from night vision scopes, silenced weapons, darting equipment and even helicopters. The ongoing civil war in the Democratic Republic of Congo and incursions by poachers primarily coming from Sudan have further disrupted efforts to protect the few remaining northern rhino.
In 2013, poaching rates for white rhinos nearly doubled from the previous year. As a result, the white rhino has now received Near Threatened status as its total population tops out at 20,000 members. Hunting of the animal has gone virtually unchecked in most of Africa, and the non-violent nature of the rhinoceros makes it susceptible to poaching. Mozambique, one of the four main countries the white rhino occupies, is used by poachers as a passageway to South Africa, which holds a fairly large number of white rhinos. Here, rhinos are regularly killed and their horns are smuggled out of the country. As of 2014, Mozambique labels white rhino poaching as a misdemeanor. 
Modern Conservation Tactics
The Northern White Rhino is critically endangered to the point that there are only three of these rhinos remaining in the world. To keep peace, several conservation tactics have been taken to prevent this species from disappearing from the earth. Perhaps the most notable type of conservation these Rhinos have received is having moved to Kenya’s Ol Pejeta Conservancy from Dvur Kralove Zoo in Czech Republic on December 20, 2009 where they have been under constant watch every day, and have been given favorable climate and diet, both of which they have adapted to well, in order to boost their chances of reproducing.
In order to save the Northern White Rhino from extinction, Ol Pejeta Conservancy announced that they will introduce a fertile Southern White Rhino from Lewa Wildlife Conservancy, In February of 2014. Here they have this Rhino in an enclosure with both female Northern White Rhinos in hopes to cross-breed the species. Having the male rhino with two female rhinos will increase competition for the female rhinos and in theory should result in more mating experiences. Till now Ol Pejeta Conservancy hasn’t announced any news of the rhino mating. 
Most white rhinos in zoos are southern white rhinos; in 2001 it was estimated that there were 777 white rhinos in captivity worldwide.
The fully captive northern white rhino population consists of only three animals, and is maintained in two zoological institutions in the U.S.A. and the Czech Republic. The San Diego Zoo Safari Park in San Diego, California, has two northern white rhinos, both of which were wild-caught. They are a female named Nola (b. 1974, on loan from 1989 from ZOO Dvůr Králové) and a male named Angalifu (b. 1974, on loan from 1990 from Khartoum Zoo in Khartoum). As of 2012, in Dvůr Králové Zoo, Dvůr Králové nad Labem, Czech Republic there is one hybrid female Nabire, born at Dvůr Králové Zoo on 15 November 1983. Her mother was a northern white rhino (C. s. cottoni), but her father was a southern white rhino (C. s. simum) named Arthur.
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