KRUGERSDORP, South Africa — An anti-poaching event went tragically wrong today when a rhino died during an operation to insert poison into its horn.
Spencer the rhino was shot with a tranquilizer dart and then treated under an experimental procedure developed by conservationists to deter poachers from killing rhinos for their horns.
In front of dozens of journalists and wildlife experts, veterinarians drilled into the sedated rhino's horn, inserting a microchip and a tracking device, as well as pink indelible dye and a toxic compound that would make a human sick if ingested. The idea is to render the horn valueless, and undesirable to poachers.
The procedure at the Rhino and Lion Nature Reserve, near Johannesburg, went smoothly, but the sedated rhino failed to wake up from the anesthesia. Instead the animal went into convulsions and died.
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Veterinarian Charles van Niekerk, who performed the procedure, said he has been involved in hundreds of rhino dartings, and 10 or 20 of the horn treatments, and had never lost an animal.
The animal likely had underlying heart complications, and had a bad reaction to the anesthetic, he said. An autopsy will determine the exact cause of death.
"I don't think our procedure, our technique, contributed in any way to its demise," van Niekerk said. "Look, this just happens. From our point of view, if we stop now then the poachers have won."
Lorinda Hern, spokeswoman for the Rhino Rescue Project and whose family owns the rhino reserve, said Spencer was in his early 20s, relatively old for a rhino.
"With every sedation there is a risk," she said, tears streaming down her face.
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South Afica has seen a dramatic rise in rhino poaching over the last few years. The country is home to an estimated 90 percent of Africa's rhino population.
A record 448 rhinos were killed by poachers last year in South Africa, an increase over 333 rhinos slaughtered in 2010. In 2007, only 13 rhinos were lost to poachers.
Rhino horns are sent to Asia, in particular Vietnam, where they are ground up and used to treat headaches or as a cancer cure, although experts say the horns have absolutely no medicinal value.
Joseph Okori, head of the WWF's African rhino program, said he attended the rhino horn procedure to learn more about this new method of fighting poaching.
"We must recognize that we are dealing with a crisis on our hands," Okori said.
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