Scientists are turning rhinos radioactive to help beat poachers

There are five species of rhinoceros in the world – black, white, Indian, Javan and Sumatran. All are under threat from poaching, with some critically endangered.

Why?

Their horns. The rhinos’ most distinctive feature is also sought after in Asian medicine, where it is ground up and used to treat everything from hangovers to cancer – with no scientific proof to suggest it works at all.

Nevertheless, poaching of the magnificent animals, alongside habitat destruction, has led to plummeting populations across Africa, India and southeast Asia.

Now however, scientists in South Africa have come up with a radical new solution – radioactive rhinos.

A team from the University of Witwatersrand has begun implanting tiny radioactive chips in the animals’ horns – a move described by one conservationist as ‘the best idea I’ve ever seen’. 

Professor Nithaya Chetty, dean of science at the university, said the radioactive material would ‘render the horn useless… essentially poisonous for human consumption’.

However, the dose will not pose any risk to the rhinos themselves or the environment around them, according to James Larkin, director of the university’s radiation and health physics unit. He added that the animals did not feel any pain from the chips.

In total, 20 rhinos will be part of the pilot ‘Rhisotope’ project, and will be administered a dose ‘strong enough to set off detectors that are installed globally’ at international border posts, originally installed to thwart nuclear terrorism, Mr Larkin said.

In addition to radiation detectors installed at ports and airports, border agents often have handheld radiation detectors that can pick up contraband, the team added.

The pioneering project has been launched at The Rhino Orphanage in Limpopo, South Africa’s northernmost province. The country, alongside neighbouring Zimbabwe and Namibia, is home to a large proportion of the world’s surviving rhinos.

In February, the South African environment ministry said that, despite its efforts to tackle the illegal trade in rhino horn, 499 individuals were killed in 2023, mostly in state-run parks – an 11% increase on 2022.

Arrie Van Deventer, who founded the orphanage, said previous efforts to deter poachers, such as dehorning rhinos and poisoning the horns, have failed.

‘Maybe this is the thing that will stop poaching,’ he said. ‘This is the best idea I’ve ever heard.’

To implant the radioisotope, Mr Larkin drills a small hole in the horn while the rhino is under anaesthetic, then hammers in the chip.   

The last phase of the project will ensure the animals’ aftercare, said the project’s COO, Jessica Babich, following ‘proper scientific protocol and ethical protocol’. The team will take follow-up blood samples to ensure the rhinos were effectively protected.

The material should last five years in the horns, which Larkin said was a cheaper method than dehorning the animals every 18 months.

Despite the fact their horns continually grow, poachers continue to kill rhinos to cut them off, rather than sedating them.

Rhino poaching surged across Africa during the pandemic, as a lack of funding caused security shortages in conservation areas. 

Earlier this month, authorities in Indonesia announced six poaching suspects were arrested, accused of being part of a network that used homemade firearms to kill more than two dozen critically endangered Javan rhinos since 2018 to get their horns.

Last year, a Malaysian man known as the ‘Godfather’, who sold a dozen black rhino and white rhino horns to a confidential source, was sentenced to a year and a half in a US prison.

There are only two northern white rhinos, a subspecies of the white rhino, left on the planet. Najin and Fatu, a mother and daughter pair, are unable to reproduce naturally, even if there was a male alive to breed with.

However, scientists are racing to develop an IVF technique that may be able to save their kind.