By Ed Stoddard
JOHANNESBURG, Jan 17 (Reuters) - More than 1,000 rhinos were poached for their horns in South Africa in 2013, a record number and an increase of over 50 percent from the previous year, the country's department of environmental affairs said on Friday.
Rhino hunting is driven by soaring demand in newly affluent Asian countries such as Vietnam and China, where the animal's horns are prized as a key ingredient in traditional medicine.
Rhino horn has a street value of more than $65,000 a kg in Asia, conservation groups say, making it more valuable than platinum, gold or cocaine.
The data is sure to ring conservation alarm bells about a downward population spiral in a country that is home to almost all of Africa and the world's rhinos, and it may bring renewed pressure on the government to do something to halt the slayings.
In 2013, 1,004 of the massive animals were illegally killed in South Africa, compared with 668 the previous year and 448 in 2011.
Most of the killings are taking place in South Africa's flagship Kruger National Park, which lost 606 rhinos last year and 425 in 2012.
The park service has been turning its rangers into soldiers, using drones to patrol airspace and sending out crack units by helicopter when suspected poachers are sighted.
The Kruger borders impoverished Mozambique, where most of the poachers are believed to be drawn from. Criminal syndicates promise cash to poor and unemployed rural villagers willing to take the risk of hunting down the animals.
"A total of 37 rhino have been poached since the start of 2014," the department of environmental affairs said.
South Africa's rhino population totals around 20,000.
Elsewhere in Africa, elephants are being poached at an alarming rate for their ivory, which is used for carvings and has been valued for millennia for its colour and texture.
The surging demand for ivory also mostly comes from rapidly growing Asian economies. (Editing by Hugh Lawson)