The white rhino (Ceratotherium simum), represents the largest extant species of rhinoceros in Africa today and is a part of the Ceratotherium genus and a member of the Rhinocerotidae family.
Being a large grazer, the white rhino lives today in Africa’s grassland and savannah habitats in countries like South Africa, Namibia, Kenya, Zimbabwe and Uganda.
Brief History of the White Rhino
The fossils found by now are showing that the white rhinoceros have evolved from a descendant (Ceratotherium praecox), which lived on Earth about 7 million years ago.
The white rhinos of today have a longer skull compared to the Ceratotherium praecox, which helps them to consume shorter grasses resulted due to the dry climate conditions specific to Africa.
However, further searches have discovered that white rhinos may have been evolved from Ceratotherium neumayri, then Ceratotherium mauritanicum and finally Ceratotherium simum.
More recently, an alternative scenario has been proposed and shows that the white rhinoceros evolved from Ceratotherium mauritanicum in Northern Africa, Ceratotherium germanoafricanum in East Africa, and from the extant Ceratotherium simum.
White Rhino Taxonomy
There are two subspecies of white rhino known today.
1. Northern White Rhinoceros
The Northern White Rhino (Ceratotherium simum cottoni) also known as the Northern Square-lipped Rhino it is considered Critically Endangered by thr UCN Red List because in the wild is more-likely extinct.
In the past, the Northern white rhino lived in the grasslands and savanna woodlands of East and Central Africa, but today we can find them mostly in captivity.
Sadly, today there are only two females of Northern white rhino in captivity (Ol Pejeta Conservancy in Kenya) and no male because the last one (Sudan), being an older male died in captivity on 19 March 2018.
2. Southern White Rhinoceros
The Southern White Rhino (Ceratotherium simum simum) is considered Near Threatened by the IUCN Red List because due to the efforts to save the species in the last decades, their number is estimated at about 17,460 individuals in the wild.
Smaller populations of southern white rhinos have been introduced within the former historical range of the species, in countries like Namibia, Zimbabwe, Botswana, Uganda and Swaziland, but also outside of their former range of countries such as Kenya and Zambia.
In Mozambique, a small population of southern white rhino has survived.
White Rhino Characteristics
The white rhino is the largest rhino among all the five species of rhino on the planet today, and has a very massive body with large head, short neck and a wide chest.
Males can reach a shoulder height between 5.60 and 6.10 ft (170 to 186 cm), while the females are slightly smaller, reaching a height between 5.25 and 5.81 ft (160 to 177 cm).
The body length of the white rhino males is between 12 and 14.8 ft (3.7 and 4.5 meters), while females are slightly shorter 11.2 to 12 ft (3.4 to 3.65 meters).
The weight of the males averages about 5,070 lbs (2,300 kg), while the females being smaller can reach a body weight of 3,750 lbs (1,700 kg).
On the head, the rhino has two ears that move independently, and on the snout, the white rhino has two horn-like growths made of solid keratin (the horns are located one behind the other).
The tail has a length of 28 in (70 cm), and helps the rhino to mark its territory.
The first horn is longer than the other and reaches on average 24 in (60 cm), while females can have a longer horn of up to 59 in (150 cm).
On the back of its neck, the white rhino has a noticeable hump and on each of its four stumpy legs has three toes.
The tail is 28 in (70 cm) in length and helps the rhinos to mark their territory.
The color of the skin varies from slate grey (the most common one) to yellowish brown.
The mouth oft he white rhino is straight and wide and is mostly used for grazing.
The olfactory passages are very large (even larger than the brain of the rhino), which shows that the animal relies most of its sense of smell.
White Rhino Behavior and Social Organization
Even being so massive and impressive, white rhinoceros are very social animals.
White rhinoceros live in herds of up to 14 individuals (mostly females), but adult males live solitary.
Adult bulls are marking their territory using urine and excrement to alert the passing rhinoceros that the territory is already occupied.
Another way of marking their territory is to wipe their horns on bushes or on the ground before spraying urine.
Bulls are marking their territory very often while while patrolling.
Subordinate males (younger males) are not marking the territory (because they don’t have one), and will congregate, often in association with an adult female in the herd.
The fights are very rare, and are not taking place for territory, bulls usually fight for the mating right over a female.
White Rhino Reproduction
White rhino females reach sexual maturity at the age of 6 or 7 years, which is way earlier than the males, which are ready to mate only at the age of 10 to 12 years.
Being large and very heavy animals, courtship is usually a difficult task for the male because he needs to give out a call when approaching the female.
If the female tries to leave the territory, the male will chase and block her while squealing or wailing loudly.
When the female is ready to mate, it enters into a stiff stance and will curl her tail to show the bull that she’s ready.
The entire act will take about half an hour, and the breeding pair will stay together between 5 and 20 days before moving on separate ways.
Gestation period will take around 16 months, and the female will give birth to only one calf.
The newborn calf weighs between 88 and 143 lbs (40 – 65 kg) and will be unsteady for the first two to three days of its life.
When threatened by predators or other rhinos, the small calf will run in front of its mother.
The mother is very protective with her calf, and will fight for him vigorously if needed.
Weaning starts pretty soon (at two months of age), but the calf can continue suckling for a period of more than one year.
A female white rhino gives birth to a new calf every two or three years, and before giving birth to a new calf, she will chase off her current calf.
Due to their size and power, adult white rhinos have no natural predators and even the younger rhino are rarely attacked due to the presence of their mother and due to their thick and tough skin.
White rhinos can live in the wild between 40 and 50 years.
White Rhino Conservation
The Northern white rhino is already extinct in the wild, and only two females live in captivity today.
The Southern white rhino instead can be found today in Southern Africa, in countries such as South Africa, Kenya, Zimbabwe, Namibia, Uganda and Mozambique.
The Southern white rhinoceros is the most common rhino on the planet today because about 777 individuals live in captivity and more than 11,670 individuals live in the wild.
The white rhino is still threatened today due to hunting and poaching, and due to habitat loss.
In the past, rhinos were hunted for their meat, but in the colonial era, they were hunted in an uncontrolled manner, which lead to a severe decline of the white rhino population.
Today hunting and poaching are mostly made for their horn even if the horn is only made from keratin (like our fingernails).