![Denis Farrell A rhino, front, recovers from a tranquilizer, after a hole was drilled into its horn and isotopes carefully inserted, at a rhino orphanage in the country's northern province of Limpopo, Tuesday, June 25, 2024. Researchers have started the final phase of a research project aimed at reducing rhino poaching by inserting radioisotopes into rhino horns to devalue one of the most highly trafficked wildlife commodities. (AP Photo/Denis Farrell)](https://mapi.associatedpress.com/v2/items/c7f94c5a609644dbae6dce20e18de72d/preview/preview.jpg?s=680x&wm=false)
A rhino, front, recovers from a tranquilizer, after a hole was drilled into its horn and isotopes carefully inserted, at a rhino orphanage in the country's northern province of Limpopo, Tuesday, June 25, 2024. Researchers have started the final phase of a research project aimed at reducing rhino poaching by inserting radioisotopes into rhino horns to devalue one of the most highly trafficked wildlife commodities. (AP Photo/Denis Farrell)
![Denis Farrell A rhino recovers from a tranquilizer, after a hole was drilled into its horn and isotopes carefully inserted, at a rhino orphanage in the country's northern province of Limpopo, Tuesday, June 25, 2024. Researchers have started the final phase of a research project aimed at reducing rhino poaching by inserting radioisotopes into rhino horns to devalue one of the most highly trafficked wildlife commodities. (AP Photo/Denis Farrell)](https://mapi.associatedpress.com/v2/items/a34775f256ac48fb926783f467d19b75/preview/preview.jpg?s=680x&wm=false)
A rhino recovers from a tranquilizer, after a hole was drilled into its horn and isotopes carefully inserted, at a rhino orphanage in the country's northern province of Limpopo, Tuesday, June 25, 2024. Researchers have started the final phase of a research project aimed at reducing rhino poaching by inserting radioisotopes into rhino horns to devalue one of the most highly trafficked wildlife commodities. (AP Photo/Denis Farrell)
![Denis Farrell A sedated rhino is prepared to be tranquilized, before a hole is drilled into its horn and isotopes carefully inserted, at a rhino orphanage in the country's northern province of Limpopo, Tuesday, June 25, 2024. Researchers have started the final phase of a research project aimed at reducing rhino poaching by inserting radioisotopes into rhino horns to devalue one of the most highly trafficked wildlife commodities. (AP Photo/Denis Farrell)](https://mapi.associatedpress.com/v2/items/44b457995853433ca61132fe4529c565/preview/preview.jpg?s=680x&wm=false)
A sedated rhino is prepared to be tranquilized, before a hole is drilled into its horn and isotopes carefully inserted, at a rhino orphanage in the country's northern province of Limpopo, Tuesday, June 25, 2024. Researchers have started the final phase of a research project aimed at reducing rhino poaching by inserting radioisotopes into rhino horns to devalue one of the most highly trafficked wildlife commodities. (AP Photo/Denis Farrell)
![Denis Farrell Professor James Larkin drills a hole into a rhinos horn to insert isotopes at a rhino orphanage in the country's northern province of Limpopo, Tuesday, June 25, 2024. Researchers have started the final phase of a research project aimed at reducing rhino poaching by inserting radioisotopes into rhino horns to devalue one of the most highly trafficked wildlife commodities. (AP Photo/Denis Farrell)](https://mapi.associatedpress.com/v2/items/3ef6d5c2d0874a26beb48b8681d904f4/preview/preview.jpg?s=680x&wm=false)
Professor James Larkin drills a hole into a rhinos horn to insert isotopes at a rhino orphanage in the country's northern province of Limpopo, Tuesday, June 25, 2024. Researchers have started the final phase of a research project aimed at reducing rhino poaching by inserting radioisotopes into rhino horns to devalue one of the most highly trafficked wildlife commodities. (AP Photo/Denis Farrell)
![Denis Farrell Professor James Larkin performs a procedure where isotopes are placed into a rhino's at a rhino orphanage in the country's northern province of Limpopo, Tuesday, June 25, 2024. Researchers have started the final phase of a research project aimed at reducing rhino poaching by inserting radioisotopes into rhino horns to devalue one of the most highly trafficked wildlife commodities. (AP Photo/Denis Farrell)](https://mapi.associatedpress.com/v2/items/4bf922e3408242c7b04f0a66f8b4909f/preview/preview.jpg?s=680x&wm=false)
Professor James Larkin performs a procedure where isotopes are placed into a rhino's at a rhino orphanage in the country's northern province of Limpopo, Tuesday, June 25, 2024. Researchers have started the final phase of a research project aimed at reducing rhino poaching by inserting radioisotopes into rhino horns to devalue one of the most highly trafficked wildlife commodities. (AP Photo/Denis Farrell)
![Denis Farrell A sedated rhino is prepared to be tranquilized, before a hole is drilled into its horn and isotopes carefully inserted, at a rhino orphanage in the country's northern province of Limpopo, Tuesday, June 25, 2024. Researchers have started the final phase of a research project aimed at reducing rhino poaching by inserting radioisotopes into rhino horns to devalue one of the most highly trafficked wildlife commodities. (AP Photo/Denis Farrell)](https://mapi.associatedpress.com/v2/items/4c6299f65fca47a69f6de2b6b8e9e0b2/preview/preview.jpg?s=680x&wm=false)
A sedated rhino is prepared to be tranquilized, before a hole is drilled into its horn and isotopes carefully inserted, at a rhino orphanage in the country's northern province of Limpopo, Tuesday, June 25, 2024. Researchers have started the final phase of a research project aimed at reducing rhino poaching by inserting radioisotopes into rhino horns to devalue one of the most highly trafficked wildlife commodities. (AP Photo/Denis Farrell)
![Denis Farrell Professor James Larkin performs a procedure where isotopes are placed into a rhino's at a rhino orphanage in the country's northern province of Limpopo, Tuesday, June 25, 2024. Researchers have started the final phase of a research project aimed at reducing rhino poaching by inserting radioisotopes into rhino horns to devalue one of the most highly trafficked wildlife commodities. (AP Photo/Denis Farrell)](https://mapi.associatedpress.com/v2/items/ca1f06568ea348b18985b600fa3a15f3/preview/preview.jpg?s=680x&wm=false)
Professor James Larkin performs a procedure where isotopes are placed into a rhino's at a rhino orphanage in the country's northern province of Limpopo, Tuesday, June 25, 2024. Researchers have started the final phase of a research project aimed at reducing rhino poaching by inserting radioisotopes into rhino horns to devalue one of the most highly trafficked wildlife commodities. (AP Photo/Denis Farrell)
![Denis Farrell Professor James Larkin drills a hole into a rhinos horn to insert isotopes at a rhino orphanage in the country's northern province of Limpopo, Tuesday, June 25, 2024. Researchers have started the final phase of a research project aimed at reducing rhino poaching by inserting radioisotopes into rhino horns to devalue one of the most highly trafficked wildlife commodities. (AP Photo/Denis Farrell)](https://mapi.associatedpress.com/v2/items/ba2c4d469ad24fd297c3817eb6cffa2c/preview/preview.jpg?s=680x&wm=false)
Professor James Larkin drills a hole into a rhinos horn to insert isotopes at a rhino orphanage in the country's northern province of Limpopo, Tuesday, June 25, 2024. Researchers have started the final phase of a research project aimed at reducing rhino poaching by inserting radioisotopes into rhino horns to devalue one of the most highly trafficked wildlife commodities. (AP Photo/Denis Farrell)
![Denis Farrell A sedated rhino is prepared to be tranquilized, before a hole is drilled into its horn and isotopes carefully inserted, at a rhino orphanage in the country's northern province of Limpopo, Tuesday, June 25, 2024. Researchers have started the final phase of a research project aimed at reducing rhino poaching by inserting radioisotopes into rhino horns to devalue one of the most highly trafficked wildlife commodities. (AP Photo/Denis Farrell)](https://mapi.associatedpress.com/v2/items/574a6fea7b594821874354e96ac11a2d/preview/preview.jpg?s=680x&wm=false)
A sedated rhino is prepared to be tranquilized, before a hole is drilled into its horn and isotopes carefully inserted, at a rhino orphanage in the country's northern province of Limpopo, Tuesday, June 25, 2024. Researchers have started the final phase of a research project aimed at reducing rhino poaching by inserting radioisotopes into rhino horns to devalue one of the most highly trafficked wildlife commodities. (AP Photo/Denis Farrell)