Rhinoceroses are the second largest land mammal on the earth and are widely described as a ‘keystone species’, meaning those which hold a disproportionately significant role within certain ecosystems. At the start of the 20th century, approximately 500,000 rhinoceroses roamed across Africa and Asia, shaping and interacting with the vast savannah and forest landscapes they inhabited. Yet, by 1970 rhino numbers were down to approximately 70,000, dwindling further with each passing year. Today, rhino population estimates stand at approximately 27,000.
Although widespread conservation efforts have prevented the complete extinction of all Asian and African rhino species, rampant poaching, habitat loss, climate change and disengaged communities continue to threaten the existence of these remarkable animals. Several subspecies have suffered extensive population declines, resulting in some being declared ‘Critically Endangered’, ‘Extinct in the Wild’ and even ‘Extinct’ under the IUCN Red List. Nevertheless, intensive protections awarded to remaining rhino strongholds have already made a significant impact on the population trends of some.
At present, there are five species of rhino that continue to roam the earth, some comprised of several different subspecies. The two species native to Africa are the black rhino and the white rhino, whilst the greater one-horned rhino, the Javan rhino, and the Sumatran rhino are all native to Asia. Although there is no exact population count for most of the remaining rhino subspecies, informed estimates have provided conservationists with a relative understanding of whether current strategies have been successful and what actions to take next.
Native to Africa, there are two genetically distinct subspecies of white rhinoceros: the northern white rhino and the southern white rhino.
The habitat range of northern white rhinos previously included Uganda, Chad, Sudan, South Sudan, the Central African Republic, and the Democratic Republic of the Congo. After decades of civil war and growing demands for rhino horn, the subspecies was declared ‘Extinct in the Wild’ in 2008 as only eight northern white rhinos remained in the world, all residing in two zoos.
In 2009, four northern white rhinos who were located at Dv?r Králové Zoo in the Czech Republic, two males and two females, were flown to Ol Pejeta Conservancy in Kenya in an effort to facilitate natural breeding between the rhinos. However, after unsuccessful attempts at mating, the two last male northern white rhinos unfortunately passed away, Suni in 2014 and Sudan in 2018, both of natural causes. Now, only two female northern white rhinos remain, Najin and Fatu, both living at Helping Rhinos’ partner project, Ol Pejeta Conservancy and they are heavily protected by armed guards. Listed as ‘Critically Endangered (Possibly Extinct in the Wild)’ by the IUCN, the northern white rhino is widely regarded as ‘functionally extinct’; although promising advancements have been made with conservationists successfully creating northern white rhino embryos to be implanted into surrogate southern white rhinos through in vitro fertilisation in the future.
In contrast, the southern white rhino is currently the most populous rhino subspecies with approximately 16,000 individuals roaming the savannahs of Kenya, Namibia, Zimbabwe and South Africa. At the end of the 19th century, the subpopulation was considered to be extinct until a small group of 20 to 50 individuals was located at the Hluluwe-iMfolozi Wildlife Park in Kwazulu-Natal, South Africa. In one of the most successful collective conservation efforts of the century, the southern white rhino now flourishes in the protected areas and game reserves dedicated to its preservation with an IUCN status of ‘Near Threatened’. Nevertheless, increasing levels of rhino poaching in recent years, compounded by decreasing state budgets for conservation, continue to pose a risk of extinction to the subpopulation.
The second native African rhino species is the black rhino, which includes four subspecies: the Southern-Central black rhino; the Eastern black rhino; the South-western black rhino; and the Western black rhino. With a habitat range that once spanned sub-Saharan Africa, black rhinos suffered the most drastic population decline of all rhinoceros species, losing 96% of their numbers between 1970 and 1993. Left with a population of just 2,300, the implementation of concentrated anti-poaching efforts and strategic translocations to protected areas and private game reserves in historic rhino habitats has allowed black rhino populations to gradually recover over time. The total black rhino population estimate now stands at approximately 6,487.
Once distributed across southern Sudan, Ethiopia, Somalia, Kenya, northern-central Tanzania and Rwanda, the Eastern black rhino population is now estimated at 583, with a stronghold in Kenya and growing subpopulations in South Africa and northern Tanzania. The subspecies has been classified as ‘Critically Endangered’ since 2000 due to the continued threat posed by poachers, yet increased protections awarded to subpopulations and a strong focus on biological management to ensure productive breeding has made conservationists hopeful of their recovery.
The Southern-Central black rhino (or South-Eastern black rhino) once roamed across Tanzania, Zambia, Zimbabwe, Mozambique, northern South Africa, southern Democratic Republic of the Congo, northern Angola, eastern Botswana, Malawi, and Eswatini (formerly Swaziland). Today, with a population of approximately 1,225 rhino, strongholds exist in South Africa, Zimbabwe, and southern Tanzania. The subspecies has also been reintroduced to several historic ranges, contributing to the 80% population increase they experienced from 1994 to 2018. However, given the scale of past population declines, as well as a comparatively delayed underlying population growth rate, the South-eastern black rhino has retained its classification of ‘Critically Endangered’ since 2000.
Due to the successful conservation strategies implemented by Namibia, the main range state of South-western black rhino, the subspecies has been classified as ‘Near Threatened’ by the IUCN after sustaining a population of over 1,000 for five consecutive years. Despite having a similar population estimate to the South-eastern black rhino, the South-western black rhino was afforded better protections against poachers in the 1990s, allowing the subspecies to build its population over a longer span of time; whereas the other two extant subspecies were both subject to rampant poaching-induced populations declines until the mid-1990s. Nevertheless, as the conservation of South-western black rhinos depends primarily on the continued expenditure of high-level security and conservation efforts, any reductions could lead to an increase in poaching and thus threaten the subspecies with extinction.
Unfortunately for the Western black rhino, intense anthropogenic pressures in their last known range state of Cameroon proved fatal to the subpopulation. Extensive surveys in 2006 failed to uncover any sightings or traces of rhino, but rather exposed extensive evidence of poaching and falsified reports of rhino spoor by local monitors. Given the extent of wildlife poaching, the lack of political commitment to conservation in Cameroon, and the increasing demand for rhino horn, the subspecies was declared extinct in 2011 by the IUCN.
The Javan rhino is one of the three rhino species found in Asia and is amongst the most endangered of all five rhino species with a population of approximately 76 rhino. There are three valid taxa of Javan rhinoceros subspecies: the Indonesian Javan rhino, the Indian Javan rhino, and the Vietnamese Javan rhino.
The Indian Javan rhino was historically found across north eastern India, Bangladesh, and Myanmar. However, the subspecies was likely hunted to extinction in the early 20th century.
The Vietnamese Javan rhino once roamed the forests of Vietnam, Lao PDR, Cambodia and eastern Thailand. After decades of poaching and habitat loss, due largely to the inadequacy of security measures within protected areas, extensive surveys of Cat Tien National Park in 2009 determined the existence of only one Vietnamese Javan rhino in the area. In April 2010, the last Vietnamese Javan rhino was hunted by poachers, having been found with her horn removed, thus rendering the subspecies extinct.
The Indonesian Javan rhino is the sole extant subspecies of Javan rhinoceros, with a population of 76 rhino in the Ujung Kulon National Park, on the western tip of Java. The subspecies has been confined to the national park since the 1930s, prior to which they could be located from Thailand to Malaysia, to the islands of Java and Sumatra. As such, the subspecies is categorised as ‘Critically Endangered’ under the ICUN Red List; although protection of the last remaining population at Ujung Kulon National Park in Indonesia is having a good degree of success with no poaching incidents reported since 2005.
Similarly to the Javan Rhino, the Sumatran rhino is one of the most endangered rhino species with a population of approximately 34 to 47 individuals. There are three subspecies of Sumatran rhino: the Northern Sumatran rhino, the Eastern Sumatran rhino (or Bornean rhino), and the Western Sumatran rhino.
The Northern Sumatran rhino was once found in India, Bhutan, Bangladesh, and Myanmar. Although the subspecies was declared ‘Extinct in the Wild’ numerous times by authorities in India, Bhutan and Bangladesh in the early 20th century, there remains a slight chance that a small population still exists in northern Myanmar - however this is highly doubted by scientists due to the political instability and inadequacy of conservation measures within the country.
The Eastern Sumatran rhino is native to the island of Borneo. In March 2016 a young female Eastern Sumatran rhino was captured in East Kalimantan (Indonesian Borneo), thus proving the subspecies’ continued existence in the wild in the Indonesian side of Borneo - although scientists estimate a mere 10 rhino exist in the region. In 2019, the government of Malaysia declared the subspecies to be ‘Extinct in the Wild’ in Sabah (Malaysian Borneo), with just one captive, non-reproductively viable female Sumatran rhino remaining at the Tabin Wildlife Reserve.
The Western Sumatran rhino once roamed across Peninsular Malaysia, Sumatra, and Thailand. After decades of poaching, habitat loss and human disturbance, the subspecies is now believed to exist solely within in three protected areas across Sumatra - Bukit Barisan, Gunung Leuser, and Way Kambas National Parks - with the largest population located within the Leuser Ecosystem of northern Sumatra. However, the existence of a subpopulation in Bukit Barisan Selatan National Park has been questioned recently due to a lack of sightings and an increase in habitat loss in the region.
Despite the fact that Sumatran rhino populations remain in existence (mainly on the island of Sumatra, with a few scattered in Kalimantan), these remaining rhino live in small, fragmented, non-viable populations with limited breeding opportunities. Due to their geographical proximity to China and Vietnam, two key rhino horn consumer countries, the Sumatran rhino has been a primary target of the illegal wildlife trade for decades. Habitat loss due to human encroachment, agriculture, palm oil plantations, infrastructure development, and catastrophic natural events has placed further pressure on the survival of the species, and as a result they have been classified as ‘Critically Endangered’ by the IUCN since 1996.
GREATER ONE HORNED Rhino
Also known as the Indian rhino, the greater one-horned rhino once inhabited the entire northern region of the Indian subcontinent, from Pakistan to the Indian-Burmese border, including sections of Nepal, Bangladesh, and Bhutan. The species suffered a drastic population decline from 1600 to 1900, reaching the brink of extinction at the start of the 20th century with a population of approximately 200 rhino. However, due to concentrated conservation efforts in key range states, the current population stands at around 4,014 rhino with subpopulations across eight protected areas in India and four in Nepal. Nevertheless, these subpopulations are considered fragmented and at risk of extinction from unpredictable catastrophic events, especially since 70% of the remaining greater one-horned rhino population is located at Assam's Kaziranga National Park, an area prone to severe annual flooding.