Last year, radioactive boars frustrated hunters in Germany. This year poisonous rhinoceroses are discouraging poachers in South Africa.

Like the boars, the rhinos are not a product of nature, but a result of human actions. In this case though, the toxic treatment was intentional.

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The Rhino and Lion Nature Reserve in Krugersdorp, north of Johannesburg, South Africa, discovered that a medical mixture used to kill parasites on the rhinos also made their horns toxic to humans. The AFP recently reported on this new tool in the fight to protect wildlife.

The treatment helps the health of the horn-heads by preventing parasites, but causes convulsions and headaches in any human who partakes in a rhino horn home remedy. Rhino horn is made of keratin, the same material as fingernails and hair, and prized in parts of Asia an an aphrodisiac and for other medicines.

The mixture also contains a dye that makes the horns glow neon pink in an airport scanner, even when ground into powder.

“The chemicals have the dual threat of keeping away both natural and human parasites… and last for three to four years,” said Lorinda Hern in an interview with the news agency SAPA.

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“A permanent solution would be to eliminate the demand for rhino horn altogether,” said Hern.

But that doesn’t seem likely to happen anytime soon.

The South African national parks agency reports that 279 rhinos have been killed in South Africa so far in 2011. Poaching has soared in recent years, from just 13 cases in 2007. This increase has been fueled by increasing wealth in East Asia and with it more people with money to buy rhino horn for traditional medicines and sex drugs.

“Education would go a long way towards teaching consumers that rhino horn contains no nutritional or medicinal value,” said Hern.

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Just as with shark fins, a creative marketing campaign by Viagra might go a long way to slow demand for animal based aphrodisiacs. In the mean time, poisonous rhinos may make poachers and consumers think twice about the illegal trade in rhino horn.

Tim Wall reports from Siguatepeque, Honduras, where he teaches journalism to fifth and sixth grade public school students.

IMAGE: A rhinoceros in South Africa (Wikimedia Commons)