Black Rhinoceros

About the black rhinoceros

The black rhinoceros, also called the hooked-lip rhinoceros, is native to East and Southern Africa, found in Angola, Botswana, Eswatini, Kenya, Lesotho, Malawi, Mozambique, Namibia, South Africa, Tanzania, Zambia, and Zimbabwe. Despite the name, its color actually ranges from brown to grey rather than true black; it's the only living species in the genus Diceros. Africa's other rhino, the white rhinoceros, is a separate species, and the two are now often distinguished by lip shape instead of color — square-lipped for the white rhino, which grazes on grass, and hook-lipped for the black rhino, which browses leaves and twigs.

An adult black rhino stands 1.32 to 1.8 m (4.3–5.9 ft) at the shoulder and runs 2.8 to 3.75 m (9.2–12.3 ft) in length, typically weighing 800 to 1,400 kg (1,800–3,100 lb), though unusually large males have reached up to 2.9 metric tons. Cows are smaller than bulls. Two horns made of keratin sit on the skull, with the larger front horn usually about 50 cm (1.6 ft) long and, exceptionally, up to 135.9 cm (4.5 ft) — the longest ever recorded measured nearly 1.5 m (4.9 ft). A third, smaller horn sometimes develops. The horns serve for defense, intimidation, and digging up roots or breaking branches while feeding. The species also carries a pointed, prehensile upper lip used to grasp leaves and twigs, in contrast to the white rhino's square grazing lip, and it holds its head higher than the white rhino as a result of its browsing posture.

Thick, layered skin protects black rhinos from thorns and sharp grasses, but it also hosts external parasites like mites and ticks, which oxpeckers and egrets pick off — though recent evidence suggests oxpeckers may actually feed on the rhino's blood rather than purely benefiting it. Despite a long-standing assumption that rhinos have poor eyesight, studies show black rhino vision is comparable to a rabbit's, and their wide-rotating ears and strong sense of smell add further defenses against predators.

Behavior and diet

Black rhinos are generally solitary, with the strongest bond in their social lives being between a mother and her calf; bulls and cows form only a temporary consort relationship during mating, and young adults sometimes form loose associations with older individuals. They aren't strongly territorial and often move through overlapping ranges. Home range size depends heavily on food and water availability — in the Serengeti, ranges run about 70 to 100 km2 (27–39 sq mi), while in the more resource-rich Ngorongoro Crater, ranges shrink to 2.6 to 58.0 km2 (1.0–22.4 sq mi). Black rhinos also return repeatedly to preferred resting spots on high ground, sometimes called "houses."

As browsers, black rhinos use their prehensile upper lip to grasp leaves and twigs rather than grazing on grass. They're known for a reputation of extreme aggression, charging readily at perceived threats — even inanimate ones like tree trunks and termite mounds — and they have the highest recorded rate of mortal combat of any mammal: about 50% of males and 30% of females die from combat-related injuries. Despite that, adult rhinos have essentially no natural predators thanks to their size, thick skin, and horns, though crocodiles have taken adults in rare cases and lions occasionally prey on calves. They can run up to 55 km/h (34 mph) on their toes, and they follow the same trails elephants use between foraging grounds and water holes.

Captive black rhinos have been studied for sleep patterns, with males sleeping nearly twice as long on average as females; sleep timing, though not overall duration, also varies with location within a captive setting.

Range and habitat

The black rhino's historic range covered most of southern and eastern Africa, excluding the Congo Basin, the tropical rainforest along the Bight of Benin, the Ethiopian Highlands, and the Horn of Africa; its presence in the driest parts of the Kalahari Desert is uncertain. It was once abundant from Eritrea and Sudan through South Sudan to southeastern Niger, particularly around Lake Chad, though its range further west is questioned by more recent research.

Today the species survives only in protected nature reserves, having vanished from many countries where it once thrived, especially in the west and north of its former range. Reintroduction programs have restored black rhinos to areas where they had gone extinct, including Malawi (extinct in 1990, reintroduced in 1993), Zambia's North Luangwa National Park (extinct 1998, reintroduced 2008), and Botswana (extinct 1992, reintroduced 2003). In May 2017, 18 eastern black rhinos were moved from South Africa to Rwanda's Akagera National Park, where the population had dropped to zero by 2007; a calf born there in September 2017 brought the total to 19, and the park now runs dedicated rhino monitoring teams against poaching.

Conservation status

The black rhinoceros is listed as Critically Endangered on the IUCN Red List, based on a 2020 assessment, though one subspecies — the south-western black rhinoceros — is separately assessed as Near Threatened. The IUCN estimates about 3,142 mature individuals remain in the wild. Poaching and habitat reduction are its two primary threats. Three subspecies have already been declared extinct, including the western black rhinoceros, which the IUCN formally declared extinct on 10 November 2011 after an intensive 2006 survey of its last known Cameroon range failed to find any survivors.

Conservation efforts now center on reintroduction and translocation between protected areas and, in some cases, across national borders. In October 2017, the governments of Chad and South Africa agreed to transfer six black rhinos to Zakouma National Park in Chad, which would become the species' northernmost population once established; the agreement called for South African experts to first assess habitat, security, and infrastructure in Chad before any transfer took place.