Officials said 405 rhinos had been killed for their horns so far in 2011 – 229 in the giant Kruger National Park alone – representing a 22 per cent increase on the 2010 figure.
Arrests of poachers have risen by 27 per cent to 210.
South Africa is home to 90 per cent of Africa’s white rhino population.
The South African government has banned hunting the animal and the sale of its products in an attempt to stop poaching, but with little success. Kruger National Park is one of the biggest in the world, and roughly the size of Israel. It is also part of a Great Transfrontier Park that links reserves along South Africa’s borders with Zimbabwe and Mozambique, through which poachers can pass with ease.
In recent years, rhino horn – which had a reputation as an aphrodisiac – has gained in popularity among the newly rich in Vietnam and other Asian states, where it is seen as a cure for cancer.
This has caused its price to rise to nearly £36,500 a kilo, making it far more expensive than gold, according to the International Rhino Foundation.