Black rhinos and white rhinos are not named for their colours, but for the shape of their lips. The black rhino has a prehensile (or grasping) upper lip, which it uses to draw plant material into its mouth. This two-horned rhinoceros has a reputation for being unpredictable and dangerous. As a result it has suffered much more persecution than other rhinos. The total population decreased by a massive 96% between 1970 and 1992, the largest decline of any of the rhino species. Four subspecies are recognised, of which three are considered Critically Endangered.
Evolutionary Distinctiveness
Order: Perissodactyla
Family: Rhinocerotidae
Together with equids (horses, zebras and asses) and tapirs, rhinos are the only surviving members of an ancient and formerly diverse group of ungulates, which originated in the Eocene around 50 million years ago. The ancestors of the black and white rhinos reached Africa about 10 million years ago, at the end of the Miocene. The black rhino diverged from the white rhino between four and five million years ago, and is considered to be the more primitive of the two. It is the only species in the genus Diceros.
Description
Size: Head and body length: 300-375 cm
Order: Perissodactyla
Family: Rhinocerotidae
Together with equids (horses, zebras and asses) and tapirs, rhinos are the only surviving members of an ancient and formerly diverse group of ungulates, which originated in the Eocene around 50 million years ago. The ancestors of the black and white rhinos reached Africa about 10 million years ago, at the end of the Miocene. The black rhino diverged from the white rhino between four and five million years ago, and is considered to be the more primitive of the two. It is the only species in the genus Diceros.
Description
Size: Head and body length: 300-375 cm
Shoulder height: 140-180 cm
Tail length: 70 cm
Horn length: 500 mm (anterior horn)
Weight: 800-1,400 kg
The black rhino is not black at all, but a yellow-brown or grey colour. It acquired its name to separate it from confusion with the other African species, the white rhino. While it is slightly darker in colour than the white rhino, its main distinguishing feature is its prehensile, or grasping, upper lip. This hook-shaped lip sticks out beyond the lower one and is used to draw food into the mouth. The rhino has two horns made from keratin (the same protein found in human hair and nails). The longest of these horns can grow to over 50 cm in length.
Weight: 800-1,400 kg
The black rhino is not black at all, but a yellow-brown or grey colour. It acquired its name to separate it from confusion with the other African species, the white rhino. While it is slightly darker in colour than the white rhino, its main distinguishing feature is its prehensile, or grasping, upper lip. This hook-shaped lip sticks out beyond the lower one and is used to draw food into the mouth. The rhino has two horns made from keratin (the same protein found in human hair and nails). The longest of these horns can grow to over 50 cm in length.
Ecology
The species is a browser. Its diet is made up of a wide variety of plant material, such as leaves and twigs of woody plants and legumes, supplemented with minerals obtained from salt-licks. Individuals prefer to feed during the early morning and evening, and spend the day wallowing in mud or water holes to keep cool. The species is generally solitary, although small groups often congregate at wallows and salt-licks. Females often have overlapping home ranges and will sometimes form temporary groups that move and feed together. Females usually have their first calf at around 6 or 7 years old, and will give birth every 2-5 years thereafter. Life expectancy for the species is around 40-50 years.
The species is a browser. Its diet is made up of a wide variety of plant material, such as leaves and twigs of woody plants and legumes, supplemented with minerals obtained from salt-licks. Individuals prefer to feed during the early morning and evening, and spend the day wallowing in mud or water holes to keep cool. The species is generally solitary, although small groups often congregate at wallows and salt-licks. Females often have overlapping home ranges and will sometimes form temporary groups that move and feed together. Females usually have their first calf at around 6 or 7 years old, and will give birth every 2-5 years thereafter. Life expectancy for the species is around 40-50 years.
Habitat
Found in a variety of habitats, including grasslands, savannas and shrublands, although the preferred habitat is the transitional zone between grassland and forest. The species is restricted to areas within 25 km of a permanent water source.
Distribution
Black rhinos were once found throughout sub-Saharan Africa with the exception of the Congo Basin. Today the main populations live in reserves in South Africa, Namibia, Zimbabwe, Tanzania and Kenya.
Found in a variety of habitats, including grasslands, savannas and shrublands, although the preferred habitat is the transitional zone between grassland and forest. The species is restricted to areas within 25 km of a permanent water source.
Distribution
Black rhinos were once found throughout sub-Saharan Africa with the exception of the Congo Basin. Today the main populations live in reserves in South Africa, Namibia, Zimbabwe, Tanzania and Kenya.
Population Estimate
There are currently approximately 3,610 surviving black rhinos.
Population Trend
Population size collapsed during the last century, from an estimated 65,000 animals in 1970 to a mere 2,300 in the 1990s. Rhino numbers are now increasing, but recovery is slow and the western subspecies in particular is still very much in danger of becoming extinct.
Status
Classified as Critically Endangered (CR A2abc) on the 2006 IUCN Red List of Threatened Species. Listed on Appendix I of CITES.
Threats
The black rhino has a reputation for being unpredictable and dangerous, and has suffered much persecution as a result. Over the years, it has been killed for sport, and for its hide and meat. However, the main threat to the rhino has been the demand for its horn, and this remains the case today. In the 1970s there was huge demand for rhino horn from Yemen, where it was used to make handles for traditional daggers worn by the wealthy as status symbols. Rhino numbers plummeted as a result of subsequent poaching. Although this demand has now subsided, rhino horn is still being illegally exported to Asia for use in traditional medicine. Currently almost all rhino deaths are caused by poaching to obtain the horn. It has a huge market value, and as a result of civil unrest and wars, many poverty-stricken African farmers have been left with little option but to turn to poaching as a means of survival.
Conservation Underway
Several organisations are working to help save this species. Conservation efforts are concentrating on reducing demand for rhino horn, while at the same time increasing protection for wild populations. At present, all trade in rhino horn is prohibited, and the extent of illegal trade is monitored by TRAFFIC (the wildlife trade monitoring network of the IUCN and WWF). Conservation organisations are also working in consumer countries to draw attention to the link between the use of rhino horn and the suffering of wild rhinos, and to investigate suitable alternatives for use in traditional medicine. At the same time, national and international conservation groups have been working with African governments to develop and implement effective national conservation and management strategies, under the co-ordination of the African Rhino Specialist Group of the IUCN which has developed a detailed Action Plan for conservation of the African rhinos. Most key wild populations are now protected in reserves, which are patrolled regularly by anti-poaching teams, and a de-horning programme has been introduced in some areas in an attempt to deter poachers. Regular monitoring takes place, and attempts to reintroduce rhinos to areas of their former range have been largely successful. A captive breeding programme is also underway to safeguard against any unforeseen catastrophes occurring within the vulnerable wild populations.
There are currently approximately 3,610 surviving black rhinos.
Population Trend
Population size collapsed during the last century, from an estimated 65,000 animals in 1970 to a mere 2,300 in the 1990s. Rhino numbers are now increasing, but recovery is slow and the western subspecies in particular is still very much in danger of becoming extinct.
Status
Classified as Critically Endangered (CR A2abc) on the 2006 IUCN Red List of Threatened Species. Listed on Appendix I of CITES.
Threats
The black rhino has a reputation for being unpredictable and dangerous, and has suffered much persecution as a result. Over the years, it has been killed for sport, and for its hide and meat. However, the main threat to the rhino has been the demand for its horn, and this remains the case today. In the 1970s there was huge demand for rhino horn from Yemen, where it was used to make handles for traditional daggers worn by the wealthy as status symbols. Rhino numbers plummeted as a result of subsequent poaching. Although this demand has now subsided, rhino horn is still being illegally exported to Asia for use in traditional medicine. Currently almost all rhino deaths are caused by poaching to obtain the horn. It has a huge market value, and as a result of civil unrest and wars, many poverty-stricken African farmers have been left with little option but to turn to poaching as a means of survival.
Conservation Underway
Several organisations are working to help save this species. Conservation efforts are concentrating on reducing demand for rhino horn, while at the same time increasing protection for wild populations. At present, all trade in rhino horn is prohibited, and the extent of illegal trade is monitored by TRAFFIC (the wildlife trade monitoring network of the IUCN and WWF). Conservation organisations are also working in consumer countries to draw attention to the link between the use of rhino horn and the suffering of wild rhinos, and to investigate suitable alternatives for use in traditional medicine. At the same time, national and international conservation groups have been working with African governments to develop and implement effective national conservation and management strategies, under the co-ordination of the African Rhino Specialist Group of the IUCN which has developed a detailed Action Plan for conservation of the African rhinos. Most key wild populations are now protected in reserves, which are patrolled regularly by anti-poaching teams, and a de-horning programme has been introduced in some areas in an attempt to deter poachers. Regular monitoring takes place, and attempts to reintroduce rhinos to areas of their former range have been largely successful. A captive breeding programme is also underway to safeguard against any unforeseen catastrophes occurring within the vulnerable wild populations.
No comments:
Post a Comment