Rhinoceros, Northern White

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Rhinoceros, northern white

Ceratotherium simum cottoni

phylum: Chordata

class: Mammalia

order: Perissodactyla

family: Rhinocerotidae

status: Near threatened (listed along with southern white rhinoceros) IUCN Endangered, ESA

range: Congo, Sudan

Description and biology

The northern white rhinoceros is also called the northern square-lipped rhinoceros. The animal derives its common name from the Afrikaans (language of white South Africans of Dutch descent) word weit, meaning "wide." The reference is to the animal's wide snout. However, the word weit was mistranslated as "white," and so the animal is now known as the white rhinoceros.

The white rhinoceros is not actually white but light gray in color. Two subspecies of white rhinoceroses exist in Africa: the southern white rhinoceros and the northern white rhinoceros. The southern white rhinoceros is found in South Africa, Swaziland, Namibia, Botswana, Zimbabwe, Mozambique,

Zambia, and Kenya. The most common of all rhinos, its population numbers about 7,500.

The northern white rhinoceros has a large, square-shaped mouth that allows it to graze on short grass. The second largest land mammal (only elephants are larger), an average northern white rhinoceros has a head and body length of 12 to 13 feet (3.7 to 4 meters) and stands 5 to 6.5 feet (1.5 to 2 meters) tall at its shoulder. Its tail measures 20 to 28 inches (51 to 71 centimeters) long. The animal may weigh between 5,000 and 8,000 pounds (2,270 and 3,630 kilograms). Despite its large size, the northern white rhinoceros can gallop as fast as 25 miles per hour (40 kilometers per hour).

Northern white rhinoceroses have short legs, broad ears, and two horns on their snout (rhinoceros means "horn- nosed"). White rhinos have the largest horns of any rhinoceros species, measuring 18 to 48 inches (46 to 122 centimeters) in length. They use their horns to fight over territory and females, to defend themselves against predators such as lions and hyenas, and to dig in the ground for mineral salt. The animals have poor vision, but highly developed senses of hearing and smell.

During the heat of the day, northern white rhinoceroses rest in shady spots. To keep cool, they often wallow in mud. When no water is available, they roll in dust to keep cool and to keep insects away. They feed in the evening and in the early morning. Average feeding territory is about 0.75 square miles (2 square kilometers). Females have larger territories than males.

Male and female northern white rhinoceroses come together only to mate. Mating can take place any time of the year, but peaks in February and June. The courtship period may last between 5 and 20 days. After a gestation (pregnancy) period of about 16 months, a female gives birth to a single calf. The mother tends to the calf for two years before chasing it away to live on its own.

Habitat and current distribution

The northern white rhinoceros prefers to inhabit open grasslands and savannas that have water available. Critically endangered, the animal is found only in Congo and southern Sudan in central Africa. Its population is extremely low. Most northern white rhinoceros live in the Garamba National Park in Congo.

History and conservation measures

The northern white rhinoceros is one of the most endangered animals in Africa. In 1980, 821 of the animals existed in the wild. Just six years later, only 17 remained in Congo (then Zaire). Intensive conservation measures were begun and by 1993, the northern white rhinoceros population had increased to 33.

The northern white rhinoceros was driven to the brink of extinction by hunting, specifically for its horns (made of keratin fibers, the same material in human fingernails). For hundreds of years, humans in Asia have used the powder of ground rhino horns in medicines and aphrodisiacs (pronounced af-row-DEEZ-ee-aks; drugs or food that stimulate sexual desire). In the Middle East, daggers with rhino-horn handles are highly valued.

Despite international treaties currently banning the sale of any rhino products, poaching (illegal hunting) of the animals continues.