More than one rhino is being killed in South Africa by poachers each day -- with 2012 on target to be the worst year on record.

Some 159 rhinos have fallen victim to poachers since January, a death toll that looks set to surpass last year's grim figure of 449.  In 2007, only 13 were killed in the country.

Demand comes from parts of China and Vietnam, where new wealth has combined with an age-old myth that rhino horns can be used to cure cancer. 

Rhino horns are now worth an estimated $25,000 per pound, making their natural weapon worth more than gold.

Report: Poachers slaughter half of elephants in African park

Three rhinos were wounded in a single incident last month. Two died, but one -- named Thandi -- survived, though she remains seriously ill.

'Some glimmer of hope'
With little positive news from the frontline of the war with poachers, "Save Thandi" has become a rallying cry amongst those who care about the plight of the rhino in South Africa.

Bringing up baby ... elephants

"People are desperate to see something going right, some positive news, some glimmer of hope that we can actually do something that saves one," wildlife veternarian Dr William Fowlds said. "I think what has come through so strongly over the past month is how important every single animal is to us."

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