There are four subspecies of black rhinos: South-central black rhino, South-western black rhino, East African black rhino & the West African Black Rhino. In the 1960s 70,000 black rhinos were in Africa, in 1981 numbers dropped to 15,000, 12 years later, around 2000 remain. Cause of decline is poaching & demand for its horn. The horn is used as dagger handles & worth over $20,000 in the black market. It is a symbol of wealth in many countries. In Asia is it a valuable source of medicine.