Nuclear Security Infrastructure Revolutionises Fight Against Rhino Poaching in South Africa

In a groundbreaking initiative, the University of Witwatersrand in South Africa, with support from the International Atomic Energy Agency (IAEA), has launched a pioneering project leveraging nuclear security infrastructure to combat the illegal trade in endangered rhinos. This innovative approach, known as the Rhisotope Project, involves the safe introduction of radioactive isotopes into rhino horns to deter poaching and aid in the detection of contraband.

Over the past decade, more than 10,000 rhinos have been lost to poachers, making the illegal wildlife trade a critical global concern. South Africa, which is home to the world's largest rhino population, is at the forefront of this battle. The scale of the challenge is stark, with the South African Department of Forestry, Fisheries and Environment reporting 103 poaching incidents in the first quarter of 2025 alone. This grim reality has spurred the University of Witwatersrand to explore radical solutions to bolster conservation and law enforcement efforts.

Following two years of extensive initial trials, the Rhisotope Project officially commenced in 2021. Its core principle is the marking of rhino horns with radioactive material. This method allows the horns to be detected by existing radiation portal monitors (RPMs) that are already strategically installed at borders, seaports, and airports worldwide. These RPMs, typically used for identifying nuclear and other radioactive materials, are now being repurposed to intercept wildlife crime. IAEA Director General, Rafael Mariano Grossi, highlighted this innovative application, stating, "The Rhisotope Project shows how nuclear science and nuclear security infrastructure can be used in new ways to address global challenges". He further emphasised, "By building on already established nuclear security infrastructure, we can help protect one of the world's most iconic endangered species".

A critical aspect of the project was ensuring the safety and non-invasiveness of the procedure. In June last year (June 2024), radioisotopes were experimentally introduced into 20 rhinos. The Ghent University in Belgium conducted comprehensive health monitoring and cytological studies, which conclusively demonstrated that the method is non-invasive and poses no danger to the health of the rhinos. James Larkin, Director of the Radiation and Medical Physics Division at the University of Witwatersrand, underscored the collaborative spirit, stating, "This was an international collaboration of like-minded individuals who are trying to make a real difference in the poaching crisis". He added that after two years of digital modelling, safety testing, and detection simulations, they are ready to implement a solution capable of reducing poaching.

The project receives crucial technical and financial backing from the IAEA. This support aligns with the IAEA's broader mission to strengthen the global nuclear security system. Elena Buglova, Director of the IAEA's Division of Nuclear Security, explained how the project activates the entire global nuclear security network, noting, "The nuclear security infrastructure that exists in many countries across the world to detect the smuggling of nuclear and other radioactive material can be used to detect illicit rhino horn and any other smuggling that might be carried with it". The global network of approximately 10,000 RPMs, originally designed to detect unauthorised transboundary movement of nuclear materials, now serves a dual purpose in safeguarding wildlife.

Beyond rhinos, the success of this project paves the way for the future application of nuclear technologies to protect other vulnerable species. Larkin confirmed that the methodology could be adapted to protect elephants and pangolins – two other species heavily targeted by illegal wildlife trade. This adaptability underscores the potential for nuclear science and existing security frameworks to offer innovative solutions to a wider range of global environmental challenges.