JOHANNESBURG (AP) -- An attempt to protect a rhinoceros from poachers in South Africa by sedating it to treat its horn ended with the animal's death Thursday in front of journalists and others who had been invited to learn more about anti-poaching efforts, conservationists said.
"It's sad for us; it's the loss of another animal. It's a death that I still chalk up to poaching," said Lorinda Hern, spokeswoman for the Rhino & Lion Nature Reserve, saying extreme measures are necessary because of a poaching crisis in South Africa.
The private reserve near the capital, Pretoria, calls in veterinarians to sedate rhinos so their horns can be treated with a dye and an insecticide, and tracking and identification devices can be inserted. A male in his mid to late 20s, fairly old for such an animal, could not be revived after being sedated Thursday, Hern said.
Last year, a record 448 rhinos were poached in South Africa. Demand for rhino horn among a growing Asian middle class is believed to be driving the poaching spike in South Africa and elsewhere in Africa. Some Asians believe a rhino horn has medicinal properties, though science does not support that.
Joseph Okori, a wildlife veterinarian and a World Wildlife Fund rhino expert, was an independent observer of Thursday's procedure as part of WWF's research into anti-poaching techniques. Okori said WWF did not support infusing horns with insecticides, which can be dangerous to humans who might eat powdered rhino horn. But he said the dye, which did not affect the outward appearance of the horn, could help law enforcement officials trace horn shipments. Airport security devices can detect the dye, Okori said.
Okori said he had sedated about 50 rhinos for various reasons, including to relocate animals, in the last 15 years. He said one animal under his care had died.
"There is always a potential risk" that a sedated animal will die, Okori said. But "the whole issue is, we are facing a serious rhino poaching crisis. This is a war. The desperation is quite high for rhino owners, to do whatever it takes to protect their rhinos."
Hern said the reserve began treating horns to make them unattractive to poachers after losing a pregnant rhino and her calf to poachers in 2010. She said Thursday's death was the first among up to 20 rhinos that have undergone the procedure, and that the death would not stop the reserve from performing the procedure.
The dye permeates the horn's interior with a neon pink dye similar to that banks use to mark bills during robberies. The insecticide, which protects rhinos against ticks, can cause vomiting and other symptoms in humans. Hern said her reserve's intention was not to hurt humans, but to deter poachers from killing animals to take their horns.
Hern said tests are under way to determine the cause of death, initially attributed to complications from either the sedative or the drug intended to revive the animal.