Black Rhinoceros
Scientific name: Diceros bicornisFamily: RHINOCEROTIDAE
Order: PERISSODACTYLA
Class: MAMMALIA
SWAHILI NAME: Kifaru
IN GENERAL:
Today there are 5 species and 11 subspecies of rhinos surviving on earth.
The scientific name, Diceros bicornis, originates from Greek "di" which means "two", "ceros" which means "horn", and from Latin "bi" which means "two" and "cornis" which means "horn". The name "rhinoceros" is derived from Greek, meaning "nose horn".
There are 4 subspecies of black rhinos; the Western (Diceros bicornis longipes) Eastern (Diceros bicornis michaeli), Southwestern (Diceros bicornis bicornis) and South Central (Diceros bicornis minor).
The black rhinoceros is also commonly known as the "prehensile-lipped rhinoceros" because the upper lip is adapted to browsing on trees and shrubs and this is one of its most distinguishing characteristics. It is also known as the "hook-lipped rhinoceros", once again referring to its prehensile lip.
The black rhino is close in color to the white rhino with a grayish brown color to its skin. Several explanations are given for the origin of the name "black" rhinoceros. Some say it is because it is from the dark colored mud covering its skin after wallowing. However the color of wallowing mud can vary from yellow-brown to rust to black throughout the animals range. The name might also be a result of black being opposite of white, to distinguish between the two species of African rhino. Another explanation is that it was first seen by William Burchell along the banks of Black Umfolozi River in South Africa. William J. Burchell (1782-1863) was an accomplished naturalist and one of the greatest early African explorers. His natural history collections were massive and he is credited with having described many "new" species as a result of his explorations.
PHYSICAL CHARACTERISTICS:
The black rhino, like the white rhino, is an odd-toed ungulate with three toes. The word ungulate comes from the Latin word "ungula", meaning "hoof".
Black rhinos weigh between 1,750 and 3,000 pounds (800 – 1,350kg) and stand 4.5 and 5.5 ft. (1.4 - 1.7m) tall at the shoulder. The length of the body not including the tail ranges from 10 to 12.5 ft (3.0 -3.8m). The head of the browsing black rhino is held higher than the grass grazing white rhino and therefore it does not need the massive hump of muscles above the shoulders that are needed by the white rhino to raise its head.
Their 2 horns rest on a bony plate on the rostrum of their skull. Horns are not attached to the skull as they are in antelope and will continue to grow to their maximum length, even if broken off. The front (anterior) horn measures 20-52 in. (0.5–1.3m) long and is larger than the rear (posterior) horn which measures 1–22 in. (2-55cm). The horn is made of keratin, not modified hair like fibers, even though if you look at the base of the horns you may see fibers that resemble course hair. The evolution of the horn was most likely for impressing the opposite sex. The second horn does not appear to serve any functional purpose today. The horn is used as a weapon to stab at predators, though most often it is used to fend off other rhinos. They also use the horn as a tool to push and turn over mud in a wallow, excavate soil at salt licks and remove branches and bark from trees.
Unlike the white rhino with its broad flat lip, the black rhino has a relatively narrow snout and a lip that is pointed with a prehensile tip. All rhinos have teeth; though blacks and whites do not have incisors or canine teeth. Instead they only have large pre molars and molars on the sides of their jaws which are designed for grinding up vegetation. All rhinos have three toes on each foot; the middle toe bears most of the animal’s weight. The sole of the foot is like a smooth, tough rubbery pad. Rhino skin is very thick and rough to the touch with sparse hairs that cannot be seen from a distance. The skin of a rhino is about 3/4 of an inch thick (18 – 20mm). The skin covering the hump area of the white rhino can be more than 1 3/4 inches thick (45mm) . The skin inside the folds is baby smooth, which reduces friction between skin surfaces as the animal moves. Rhinos can gallop for short distances at speeds of 25-31 mph (40 to 50kmph).
They also have tufts of hair at the end of their tails and much more hair fringing their ears than that of the white rhino. Their eyesight is poor, but they have an excellent ability to hear and smell (reportedly better than a bloodhound)
Black rhinos weigh between 1,750 and 3,000 pounds (800 – 1,350kg) and stand 4.5 and 5.5 ft. (1.4 - 1.7m) tall at the shoulder. The length of the body not including the tail ranges from 10 to 12.5 ft (3.0 -3.8m). The head of the browsing black rhino is held higher than the grass grazing white rhino and therefore it does not need the massive hump of muscles above the shoulders that are needed by the white rhino to raise its head.
Their 2 horns rest on a bony plate on the rostrum of their skull. Horns are not attached to the skull as they are in antelope and will continue to grow to their maximum length, even if broken off. The front (anterior) horn measures 20-52 in. (0.5–1.3m) long and is larger than the rear (posterior) horn which measures 1–22 in. (2-55cm). The horn is made of keratin, not modified hair like fibers, even though if you look at the base of the horns you may see fibers that resemble course hair. The evolution of the horn was most likely for impressing the opposite sex. The second horn does not appear to serve any functional purpose today. The horn is used as a weapon to stab at predators, though most often it is used to fend off other rhinos. They also use the horn as a tool to push and turn over mud in a wallow, excavate soil at salt licks and remove branches and bark from trees.
Unlike the white rhino with its broad flat lip, the black rhino has a relatively narrow snout and a lip that is pointed with a prehensile tip. All rhinos have teeth; though blacks and whites do not have incisors or canine teeth. Instead they only have large pre molars and molars on the sides of their jaws which are designed for grinding up vegetation. All rhinos have three toes on each foot; the middle toe bears most of the animal’s weight. The sole of the foot is like a smooth, tough rubbery pad. Rhino skin is very thick and rough to the touch with sparse hairs that cannot be seen from a distance. The skin of a rhino is about 3/4 of an inch thick (18 – 20mm). The skin covering the hump area of the white rhino can be more than 1 3/4 inches thick (45mm) . The skin inside the folds is baby smooth, which reduces friction between skin surfaces as the animal moves. Rhinos can gallop for short distances at speeds of 25-31 mph (40 to 50kmph).
They also have tufts of hair at the end of their tails and much more hair fringing their ears than that of the white rhino. Their eyesight is poor, but they have an excellent ability to hear and smell (reportedly better than a bloodhound)
History
The black rhino is one of the surviving representatives of a biological category that was at one time much more diverse and abundant. These were known as the mega herbivores. There were many forms of the present day rhino 50 million years ago and their range was very extensive compared to that of today. 15,000 years ago, Europe was home to the wooly rhinoceros. Approximately 5 million years ago, today’s African rhinos diverged from a common ancestor to their present day form. The Asian rhinos divergence took place millions of years earlier.
In the early 1800’s the black rhinoceros was the most numerous of the entire world’s rhino species; the estimated population was several hundred thousand. Their range was from central-western Africa all the way to southern South Africa. Early foreign settlers to Africa reported that they were widespread and common. With the growing domination of European colonists, land use changed opening up areas to trade and farmers. The result was continual unrestricted hunting of the black rhino and other species across most of central-west and eastern Africa.
By 1933 only two breeding populations of about 110 animals survived in Southern Africa. In Kenya, for example, between 1946 and 1948 about 1,000 black rhinos were shot by one group of game control employees who were preparing an area for an agricultural settlement. Even with this level of extermination, there were still estimated to be about 100,000 animals left in Africa in 1960. However, the decline continued with an estimated population of 65,000 by 1970. In 1970, Kenya had the largest population of about 18,000 animals.
Between 1970 and 1992 the black rhino populations were reduced by 96%, reaching a low of 2,410 animals in 1995. During the 1970’s and 80’s the demand for rhino horn in Asian and the Middle East grew, combined with economic and political instability in countries with rhino populations. These factors led to uncontrolled poaching pressure. Funding for adequate anti-poaching patrols was insufficient to non existent. The political and civil unrest in many countries has resulted in the free flow of weapons into Africa and this has had a significant impact on African rhinos as well as other species and has made conservation efforts difficult and often dangerous. The biggest declines since 1980 have occurred in vast unfenced areas that were historically the black rhinos’ natural range. As a result, they are now extinct or extremely close to extinction in Zambia, the Central African Republic and Tanzania. A few survivors have been moved to protected areas such as Tsavo, Chobi/Morembi, Selous Game Reserve, Zambezi Valley and the Luangwa Valley.
In recent years, the best protected areas have shown the healthiest increases in black rhino populations and other species populations have also increased that occupy the same area.
In the early 1800’s the black rhinoceros was the most numerous of the entire world’s rhino species; the estimated population was several hundred thousand. Their range was from central-western Africa all the way to southern South Africa. Early foreign settlers to Africa reported that they were widespread and common. With the growing domination of European colonists, land use changed opening up areas to trade and farmers. The result was continual unrestricted hunting of the black rhino and other species across most of central-west and eastern Africa.
By 1933 only two breeding populations of about 110 animals survived in Southern Africa. In Kenya, for example, between 1946 and 1948 about 1,000 black rhinos were shot by one group of game control employees who were preparing an area for an agricultural settlement. Even with this level of extermination, there were still estimated to be about 100,000 animals left in Africa in 1960. However, the decline continued with an estimated population of 65,000 by 1970. In 1970, Kenya had the largest population of about 18,000 animals.
Between 1970 and 1992 the black rhino populations were reduced by 96%, reaching a low of 2,410 animals in 1995. During the 1970’s and 80’s the demand for rhino horn in Asian and the Middle East grew, combined with economic and political instability in countries with rhino populations. These factors led to uncontrolled poaching pressure. Funding for adequate anti-poaching patrols was insufficient to non existent. The political and civil unrest in many countries has resulted in the free flow of weapons into Africa and this has had a significant impact on African rhinos as well as other species and has made conservation efforts difficult and often dangerous. The biggest declines since 1980 have occurred in vast unfenced areas that were historically the black rhinos’ natural range. As a result, they are now extinct or extremely close to extinction in Zambia, the Central African Republic and Tanzania. A few survivors have been moved to protected areas such as Tsavo, Chobi/Morembi, Selous Game Reserve, Zambezi Valley and the Luangwa Valley.
In recent years, the best protected areas have shown the healthiest increases in black rhino populations and other species populations have also increased that occupy the same area.
DIET:
The black rhino uses its prehensile or hooked lip to strip leaves from vegetation and they usually feed at night and the early morning. They eat over 200 plants in 50 different families.
Black rhinos are browsers favoring small acacia’s, euphorbias, Phyllanthus fisheri and other palatable woody species as well as palatable herbs and succulents. They eat very little grass, unlike the white rhino. They are unable to eat all types of the available woody browse plants because of the high levels of secondary plant chemicals. An example of this is their inability to eat many of the evergreen species that are found in their ranges. Before this was understood, carrying capacities were over-estimated in some areas.
In Kenya, on a private ranch, a six-month study was conducted on the feeding habits of the black rhino. It was found that over 100 species of plants were identified as rhino food. The study area was very similar in plant nature to that of Tsavo National Park which has been identified as ideal habitat for the black rhino (the Masai Mara in contrast is not as rich in food sources for the rhino). When they were observed eating only specific parts of a plant during the wet season, they tended with some exceptions, to eat the same parts of the plant during the dry season. Some plants were avoided completely during the dry season. An example of this exception was the ferula communis, a giant fennel, which was the most eaten plant during the early wet season, but not eaten at all during the dry season. This may be due to chemical changes in the plants that make them less palatable. During the dry season this resulted in the animals traveling further in search of food which sometimes led to them leaving the protection of certain areas and becoming easier targets for poachers. The black rhinos in the study area tended to eat all parts of the plant during the wet season rather than just the leaves or stems; this confirmed observations made in the 1970's.
Because of their hindgut fermentation they can tolerate a high fiber diet, but prefer more nutritious leafy vegetation. If available, they will eat the large woody pods or sausages of the African sausage tree (Kigelia Africana).
To support the great bulk of their bodies, they need a large amount of browse daily. They are a dependent on water and prefer to drink daily and browse in areas with access to water. They can however, survive 4 or 5 days without water, but during this time they will chew on succulents that have high water content.
Black rhinos are browsers favoring small acacia’s, euphorbias, Phyllanthus fisheri and other palatable woody species as well as palatable herbs and succulents. They eat very little grass, unlike the white rhino. They are unable to eat all types of the available woody browse plants because of the high levels of secondary plant chemicals. An example of this is their inability to eat many of the evergreen species that are found in their ranges. Before this was understood, carrying capacities were over-estimated in some areas.
In Kenya, on a private ranch, a six-month study was conducted on the feeding habits of the black rhino. It was found that over 100 species of plants were identified as rhino food. The study area was very similar in plant nature to that of Tsavo National Park which has been identified as ideal habitat for the black rhino (the Masai Mara in contrast is not as rich in food sources for the rhino). When they were observed eating only specific parts of a plant during the wet season, they tended with some exceptions, to eat the same parts of the plant during the dry season. Some plants were avoided completely during the dry season. An example of this exception was the ferula communis, a giant fennel, which was the most eaten plant during the early wet season, but not eaten at all during the dry season. This may be due to chemical changes in the plants that make them less palatable. During the dry season this resulted in the animals traveling further in search of food which sometimes led to them leaving the protection of certain areas and becoming easier targets for poachers. The black rhinos in the study area tended to eat all parts of the plant during the wet season rather than just the leaves or stems; this confirmed observations made in the 1970's.
Because of their hindgut fermentation they can tolerate a high fiber diet, but prefer more nutritious leafy vegetation. If available, they will eat the large woody pods or sausages of the African sausage tree (Kigelia Africana).
To support the great bulk of their bodies, they need a large amount of browse daily. They are a dependent on water and prefer to drink daily and browse in areas with access to water. They can however, survive 4 or 5 days without water, but during this time they will chew on succulents that have high water content.
REPRODUCTION and GROWTH:
Their longevity in the wild is between 30 – 35 years; however they can live between 40 to 50 years of age in captivity.
Sexual Maturity for females is reached between 4 to 7 years old; however males do not reach maturity until 7 to 10 years of age.
There is no particular breeding season but conceptions tend to peak during the rains so that most babies are born in the early part of the dry season. This allows the mother’s milk supply to nourish the offspring through the most difficult time of the year when food and water is scarcer. The gestation period for the black rhino is approximately 15 to 16 months with birth intervals of a single calf occurring every 2 ½ to 4 years. The calf will stay with its mother for as long as 2 years, often remaining with her after the birth of a subsequent calf.
In the wild they have the highest incidence among mammals of fatal interspecies fighting. It is estimated that up to half the males and one third of the females die from fight wounds. This is part of the reason they have earned the reputation as aggressive and ornery animals. Populations with high mortality rates recover slowly.
High mortality rates have limited the successful breeding of black rhinos in captivity. Research has found that diseases they suffer from may be related to their unique blood chemistry. An example of this is the very low level of particular enzymes in their red blood cells. It has also been found that a diet more closely related to their natural diet has made a difference in their overall health and breeding success. The International Rhino Foundation (IRF) is very active in funding research in rhino health and reproduction in captivity.
Sexual Maturity for females is reached between 4 to 7 years old; however males do not reach maturity until 7 to 10 years of age.
There is no particular breeding season but conceptions tend to peak during the rains so that most babies are born in the early part of the dry season. This allows the mother’s milk supply to nourish the offspring through the most difficult time of the year when food and water is scarcer. The gestation period for the black rhino is approximately 15 to 16 months with birth intervals of a single calf occurring every 2 ½ to 4 years. The calf will stay with its mother for as long as 2 years, often remaining with her after the birth of a subsequent calf.
In the wild they have the highest incidence among mammals of fatal interspecies fighting. It is estimated that up to half the males and one third of the females die from fight wounds. This is part of the reason they have earned the reputation as aggressive and ornery animals. Populations with high mortality rates recover slowly.
High mortality rates have limited the successful breeding of black rhinos in captivity. Research has found that diseases they suffer from may be related to their unique blood chemistry. An example of this is the very low level of particular enzymes in their red blood cells. It has also been found that a diet more closely related to their natural diet has made a difference in their overall health and breeding success. The International Rhino Foundation (IRF) is very active in funding research in rhino health and reproduction in captivity.
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