The presently living rhinoceros are a well-defined group of animals
whose members closely resemble each other, in spite of the fact that two
of the species live on the African continent and three in Asia. The African
rhinoceros are from a separate branch (subfamily Dicerotinae) which includes
the present-day Black Rhinoceros (Diceros bicornis), which originally
fed on foliage, and the Square-Lipped Rhinoceros (Ceratotherium simum),
also know as the White Rhino, which has become adapted for feeding on grass.
|Name: White and Black Rhinoceros|
|Range: Africa, Mostly in Kenya and Zimbabwe.|
|Habitat: White Rhinos are savanna dwelling grazers, while the Black Rhino is a browser living in forest and thorn scrub.|
|Status: Black Rhino is endangered, White Rhino is Vulnerable.|
|Diet in the wild: Water grass and leaves|
|Diet in the zoo: Hay, Lucerne chaff, horse cubes, carrots and bananas as a treat.|
|Location in the zoo: African Savannah|
Rhinos; Height 1.5 - 1.75 meters at center of back, average weight
4,500 pounds. Body length up to 3.75 meters. Their color is brown;
the tail is short. Although their eyesight is poor, both hearing and sense
of smell are excellent. They have two large horns, the front one being
the largest. These horns can measure up to 50 inches in length. The
horn of all rhinos is formed of hair-like keratin fibers pressed together.
The horns are found in both sexes. The upper lip is prehensile and
helps the rhino browse through and manipulate foliage as it feeds.
Black rhino at Fort Worth Zoo
showing pointed upper lip
White Rhinos; Height 1.75 - 2.05 meters, weight between 3000 - 4000kg, head and body length 3.6 - 4.2 meters. Hips are lower than the shoulders.Their color is light gray; the tail is short and tasseled. There are two horns on the snout; the front one is usually longer. The upper lip is very broad and squared-off -- in fact the "weit" upper lip was the original basis for mistakenly calling this animal a "white" rhinoceros!
White rhino close up, showing longer front
Black rhinos are solitary animals, only coming together to mate. By contrast, the more gregarious white rhino only breeds successfully when there are small groups. The most lasting bond is between females and young, the calf staying with the mother for about five years. The black rhino is the more aggressive of the two species. It can move at speeds up to 40 miles per hour for short distances -- the speed of a race horse!
Rhinos have poor eyesight and are likely to charge any suspicious moving object without provocation. Their hearing and sense of smell, on the other hand, are very good.
White rhino males mate with any estrous female within their territory
after a long courtship session. Mating lasts 20 to 30 minutes. The female
bears a single calf; the calf suckles for at least one year but can eat
grass at two months. The calf lives with the cow for around 3 years until
the next calf is born.
Black rhino with calf "Little One."
|Special anatomical, physiological
or behavioral adaptations:
Black Rhinos Courting
Rhinos are often accompanied by oxpeckers, tick birds and cattle egrets, which feed on insects stirred up by the rhino's feet, or living in the mud on their skin.
White rhino with oxpecker
courtesy of Africam
the rhinoceros exhibit at the zoo I saw that there were several white
and black rhinos, including a calf. I noticed that unlike in the wild
they would often have more than one white rhino male in an area and
interestingly they did not seem to have a problem sharing the same territory.
White rhinos face off in courtship display
Sexual maturity: Female: 4-5 years; first calf at 6-8 years. Males 7-8 years; first territory at 10 years. Gestation 16 mouths. Life span up to 40 years.
|Page author: Obi Ibeto.|
Asian Rhinos at the Fort Worth Zoo
|Sources and Links
Black Rhino at the Smithsonian
Britannia Encyclopedia (on animals), Section R, 47-53.