South African activists turn to radioactivity to stop rhino poaching

Igor the rhinoceros stands in the Buffalo Kloof Game Reserve in South Africa before he's due to be injected with an amino acid containing special, non-radioactive isotopes of carbon and nitrogen. Photos: Jessica Shuttleworth/University of the Witwatersrand/dpa

To combat the poaching of rhinoceroses, South African animal preservationists are turning to radioactive substances: By injecting a small amount into the animals' horns, they seek to deter and detect smugglers.

If the animals' horns are taken through customs at a port or airport, alarms should sound when the substance is detected – a move activists hope will dramatically reduce smuggling.