Currently nearly 78% of the worlds surviving rhino population are located in Namibia and South Africa. Due to extreme poaching, their numbers has reached critical stages.
Rhino - Endangered wildlife of Africa

For thousands of years, Rhinos have been widely spread throughout Africa, and was a wonderful part of the natural wildlife balance of Africa. 

There are two kinds of African rhino – the white and the black rhino. There are around 20,000 white rhino and 4,800 black rhino remaining in isolated pockets in the African wilderness. These numbers are dwindling at a tremendous rate, as in 2012, about 450 rhino has been killed by poachers in South Africa alone.
 
Often people think the difference between the black and white rhino got some-thing to do with colour. Not at all! Both are grey in colour.

The Differences between a Black and White rhino.