Rhinos are the second largest land mammal on earth. At the beginning of the 20th century, 500,000 roamed Africa and Asia, but today, very few survive outside national parks and reserves due to persistent poaching and habitat loss.
The different species of rhinos
There are five living species of rhinos in the world; white, black, Indian, Javan, and Sumatran. There are two subspecies of white rhinos; the northern and the southern white rhino, and four sub-species of black rhino; western, eastern, south-western, and south-central rhino.
Rhinos can be solitary or social
For the most part, rhinoceroses are solitary animals and like to avoid each other. Some species, particularly the white rhino, may live in small groups known as a ‘crash’. These crashes are usually made up of a female and her calves, although sometimes adult females can be seen together too. Males on the other hand, like to be left alone, unless in search of a female to breed with.
Rhinos can tell a lot from a call
The more social rhino species; the southern and northern white rhinos, use a call to communicate to one another. This is called a contact call pant, and can be heard over long-distances. Researchers have found that these calls say a lot about the caller
In one study, scientists played calls from different individual rhinos to a group of ten wild southern white rhinos. They included calls made by both familiar and unfamiliar southern white rhinos, both males and females, and calls from northern white rhinos. They then monitored the behaviour of the rhinos, to see how they responded.
The researchers found that the rhinos responded differently depending on who the caller was. They found that the rhinos could tell whether the caller was familiar or unfamiliar to them, whether they were a male or a female, and whether they were a fellow southern white rhino, or a northern white rhino. They also analysed the calls and found that they differed in structure depending on whether they were performed by a male or female rhino. They found that the male rhinos tended to respond more strongly to female calls than to other males. This suggests that male to male communication is less important for rhinos than male to female communication.
In another study, researchers found that each call could be linked to an individual, in the same way that our voices are unique to us.
Rhinos have very poor eyesight, and so being able to communicate vocally with one another over long distances is crucial. This research is important because it helps us to understand more about these amazing animals. Understanding how they communicate with one another may also be critical for improving conservation efforts.
Rhinos really are amazing animals
The Javan and Sumatran rhinos in Asia are critically endangered. There are thought to be less than 80 Sumatran rhinos in the wild. A subspecies of the Javan rhino was declared extinct in Vietnam in 2011. A small population of around 70 Javan rhinos still clings to survival on the Indonesian island of Java. Successful conservation efforts have helped the third Asian species; the greater one-horned (or Indian) rhino, to increase in number. Their status was changed from Endangered to Vulnerable, and they survive in northern India and southern Nepal. A recent count suggested that there are now 3,500 of these rhinos in India and Nepal, but the species is still threatened due to poaching for their horns.
In Africa, southern white rhinos, once thought to be extinct, are another conservation success as they have been brought back to sustainable numbers. In fact, there are thought to be just under 19,000 in the wild. Like the Asian rhinos however, they too are being increasingly poached for their horns, and their numbers are now crashing. Once again risking the conservation status of these animals.
Black rhinos have doubled in number over the past two decades from their low point of fewer than 2,500 individuals, and there are now thought to be around 5000 in the wild. This is still a fraction of the estimated 100,000 that existed in the early part of the 20th century.
The western black rhino and northern white rhinos have recently gone extinct in the wild, and there are only two remaining female northern white rhinos left. They are being kept under 24-hour guard in Ol Pejeta Conservancy in Kenya.
The main threat to these beautiful animals is illegal hunting, largely because their horns are used in traditional folk medicine, particularly in Asia.
To save the remaining rhinos, countries must work together to protect conservation sites and, crucially, to stop the illegal trade in rhino horns. That means stopping the poachers who kill the rhinos, but it also means tackling a vast network of organised crime that ships the horns to China and other Asian countries.
It is also important to end the demand. Rhino horns are status symbols in China, and so people pay lots of money for them. If demand could be stopped, then at least some of the rhino species could start to recover. It may well be too late for some of the species and subspecies whose populations are now so small they could never recover, but it is not too late for them all.
For more information on how you can help to protect rhino’s in the wild see;
Save the Rhino
World Wildlife Fund
International Rhino Foundation