The smaller of the two African species, its population has declined by an estimated 98% since 1960 and there are now less than 5,000 in the wild.
The two subspecies of white rhino are faring very differently - the northern white rhino is close to extinction but conservation has restored Africa's southern white rhino population to around 20,000.
Also known as the Indian rhino, successful conservation efforts have seen this species increase in number to around 3,000.
Once found throughout south-east Asia, the species is now confined to one small population of less than 50 individuals in Java, Indonesia.
A population of around 200 of the smallest living rhino now clings to survival in forests on the islands of Sumatra and Borneo.
Jessica Aldred
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