Black Rhinoceros
Tagged: animal, animals, cat, mammalDiceros bicornis
( image )
Formerly abundant and widespread in Africa, the black rhinoceros has been drastically reduced in numbers since the 1970s. The main culprit is the expanding international trade in rhino horn. Although the black rhinoceros is able, if necessary, to go for five days without water, it is generally found in relatively moist areas of lush vegetation. Throughout Africa these regions are under pressure for development into farm and grazing land, effectively excluding the rhinos, which are too large and unpredictable to be tolerated close to human settlements. Yet the main threat to the animals comes not so much from habitat loss as from hunting, principally for their horns for use in oriental medicine. For centuries rhino horn, composed of densely compressed hair, has been powdered and swallowed as a remedy for fevers and other disorders. It is made of keratin (a fibrous substance that occurs in skin, hair, nails, and hooves) and cannot be absorbed into the body, so any supposed medicinal benefits will only be imaginary. Yet the horns continue to fetch high prices, often earning more than their weight in gold. In recent years a new factor has further complicated the situation. In Yemen in southwestern Asia there has long been a tradition of using rhino horn to make carved dagger handles. As oil money brought new prosperity to the region, the demand for these prestigious status symbols increased; in 1999 more than 100 craftsmen were employed in making and repairing such artifacts. Old and new horns were used; at the time, new horns were said to be fetching $615 per pound ($1,350 per kg), 20 percent more than they had only two years earlier. Before hunting reduced their numbers, black rhinos could be found in the bush and savanna regions of most of Africa south of the Sahara. By the 1960s they were already becoming rare, but were still 110 widely distributed, with substantial numbers in Kenya, Tanzania, and Zimbabwe. Although the animals enjoyed legal protection, the lucrative trade in horns could not be controlled, and the rhino died out in one area after another as hunting took its lethal toll.
Slow Breeders
The black rhino has one of the slowest reproductive rates of any large mammal, making it ill equipped to cope with population loss. Young animals first breed at five or even 10 years, but in practice many are killed long before they reach that age. Calves are not born annually, but at intervals of up to five years. In the past this was not a disadvantage; the slow breeding rate was probably a natural adaptation to avoid producing more young than the available resources could support. Excessive hunting has, however, overwhelmed the animal’s capacity to maintain its numbers, which have fallen by more than 90 percent since 1970. The total figure now seems to have stabilized, but several countries where the species was once common now have fewer than 50 black rhinos, most of them confined to national parks and reserves. Thanks to the high cash value of the horns, the killing continues; a poacher can earn more from one dead rhino than from a year’s farmwork. One possible solution might be to remove the horns, which contain no nerve endings and can be painlessly cut away without disrupting the rhino’s life. However, the horns grow back, so the process would have to be repeated. Even so, such a program would remove the incentive for poaching and might prove more practicable in the long run than captive breeding, which is the only other way of ensuring the rhino’s long-term survival.
Statistic
Black rhinoceros
Diceros bicornis
- Family: Rhinocerotidae
- World population: About 2,550 (1994 estimate)
- Form: Large, thick-skinned animal; grayish in color but often coated with dust or mud. Two horns on the snout and a pointed, mobile upper lip, used like a miniature trunk to gather food
- Distribution: Africa south of the Sahara, in widely scattered localities
- Habitat: Bush and savanna; rarely found more than a day’s walk from water
- Size: Length head/body: 9.5-12.3 ft (2.9-3.7 m); tail: 24-28 in (60-70 cm); height at shoulder: 4.5-5.9 ft (1.4-1.8 m). Weight: 1,500-3,000 lb (700-1,400 kg)
- Diet: Leaves, twigs, and branches browsed from more than 200 species of low-growing shrub
- Breeding: Single calf born after 15month gestation; suckled for up to 1 year. Life span may exceed 40 years
- Related endangered species: White rhinoceros (Ceratotherium simum); great Indian rhinoceros (Rhinoceros unicornis); Javan rhinoceros (R. sondaicus); Sumatran rhinoceros (Dicerorhinus sumarrensis
Comments
Got something to say?