White Rhinoceros

The white rhinoceros is the second-largest land animal on Earth, after the elephant, and its recent history is a warning about how quickly conservation gains can be lost. It was brought back from the very edge of extinction, then driven partway back toward it by demand for its horn.

Overview

There are two subspecies. The southern white rhino grazes the grasslands and savannas of South Africa, Namibia, Zimbabwe, and neighbouring countries. The northern white rhino, once found in Central Africa, is down to two elderly females living under armed guard in Kenya — the last of their kind.

White rhinos are the most sociable of the five rhino species, forming loose groups (“crashes”) of females and young, while adult bulls hold and mark territories.

Physical characteristics

A big bull white rhino weighs 2–2.5 tonnes and can approach 3.6. The body is grey (see the FAQ on the name), nearly hairless, with a pronounced hump of muscle on the neck to support the huge head. The defining feature is the wide, straight, squared-off upper lip, an adaptation for mowing short grass — the black rhino, by contrast, has a hooked lip for pulling leaves off branches.

Both horns are made of tightly packed keratin, the same material as hair and nails, growing continuously from the skin. Eyesight is poor — a rhino may not recognise a person standing still at 30 m — but hearing and smell are excellent, and the ears swivel independently.

Diet and behaviour

White rhinos are bulk grazers, spending about half the day eating and much of the rest resting or wallowing in mud, which cools the skin and deters biting insects. Oxpecker birds ride on their backs, eating ticks and giving an alarm call at danger.

Communication runs on scent. Bulls create communal dung heaps called middens; every rhino in the area visits them, reading who has passed through, and adds its own contribution.

Reproduction and life cycle

After a pregnancy of around 16 months, a female gives birth to a single calf weighing about 40–65 kg. The calf runs in front of its mother (black rhino calves run behind), staying with her for two to three years until the next calf is born. Females breed every two to five years, so the population grows slowly.

Threats and conservation

The white rhino is Near Threatened, and its story has two halves:

• The recovery. From under 100 animals in 1900 to more than 20,000 by 2012 — the result of decades of protection and active management.
• The poaching crisis. From around 2008, organised criminal networks drove a sharp rise in rhino killing to supply horn to markets in Vietnam and China, where it is used as a status symbol and a supposed medicine. South Africa alone lost over 1,000 rhinos a year at the peak.

Anti-poaching patrols, dehorning, moving rhinos to safer sites, and demand-reduction campaigns have slowed the losses, and the southern white rhino is once again edging upward. The northern subspecies, though, is beyond saving by conventional means.