University of Oxford researchers have contributed to an international study which found that dehorning rhinos resulted in a drastic reduction in poaching of these endangered animals. The findings have been published this week in the prestigious journal Science.
This collaboration is a brilliant example of how the effectiveness of conservation interventions can be assessed quantitatively, even in challenging and complex situations, and how important the participation of on-the-ground practitioners is in initiating, and interpreting, such research.
The study analysed data from 11 reserves in the Greater Kruger region of South Africa between 2017 and 2023. This landscape is a critical global stronghold that conserves around 25% of all Africa’s rhinos. During the seven-year period, 1,985 rhinos (about 6,5% of the Greater Kruger area population annually) were poached for their horns.
Lead author, Dr Tim Kuiper of Nelson Mandela University (George campus) said: ‘Dehorning rhinos to reduce incentives for poaching (2,284 rhinos were dehorned across eight reserves) was found to achieve a 78% reduction in poaching using just 1.2% of the overall rhino protection budget.’ This was based on comparison between sites with and without dehorning as well as changes in poaching before and after dehorning.
The study did show, however, that some poaching of dehorned rhinos for horn stumps and regrowth continued, while more recent evidence (2024-2025) since the conclusion of the study in 2023 suggests this is a growing challenge. Dehorning may also shift the focus of poachers to horned populations elsewhere.
Dame E.J. Milner-Gulland, Professor of Biodiversity for the University of Oxford’s Department of Biology, supported the study through providing expert advice on bioeconomics, impact evaluation, and wider assessment of the conservation context of the work.She said: ‘This study has important implications, not just for rhino management, but also more broadly for conservationists planning and implementing interventions. It also suggests that it is worth thinking of ways to reduce the expected profitability of poaching (in this case through dehorning), rather than only focusing on increasing the expected risks and costs.’
Reserves included in the study’s assessment invested $74 million (R1 billion) in anti-poaching interventions from 2017-2021. Most of the investment focused on reactive law enforcement — rangers, tracking dogs, helicopters, access controls, and detection cameras — helping achieve over 700 poacher arrests. Yet the authors found no statistical evidence that these interventions significantly reduced poaching.
Interventions that work to aid poacher detection and arrest, while a necessary element of the anti-poaching toolkit, are compromised by systemic factors, such as local poverty (driving people to take risks) and corruption. Ineffective criminal justice systems can also mean that arrested offenders often escape punishment.In a shining example of science-policy collaboration, this project was first conceived by reserve managers at the frontline of rhino conservation who recognised the need to critically evaluate their investments into anti-poaching interventions (from tracking dogs to AI cameras). The Greater Kruger Environmental Protection Foundation (GKEPF) led the initiative by convening manager workshops and gathering data for the evaluation.
Professor Milner-Gulland added: ‘This collaboration is a brilliant example of how the effectiveness of conservation interventions can be assessed quantitatively, even in challenging and complex situations, and how important the participation of on-the-ground practitioners is in initiating, and interpreting, such research.’
Sharon Hausmann, CEO of GKEPF, was the intermediary between the managers and scientists. She said, ‘The true value of this innovative study, conceived by GKEPF operational managers, lies in its collective critical thinking. Ensuring not only that operations are guided by science, but also that science is grounded in real experience from the frontline.’
From a donor perspective this study has given excellent insight where conservation donor funding can be spent and where to avoid funding.
Dr Markus Hofmeyr, Rhino Recovery Fund
The research results present an opportunity for government, funders, the private sector, and NGOs to re-reassess their strategic approaches to wildlife crime in general and rhino poaching in particular.
The study ‘Dehorning reduces rhino poaching’ has been published in Science.
The project was a collaboration between reserve managers under the banner of the GKEPF and scientists from the University of Oxford, the University of Cape Town (UCT), Nelson Mandela University, and the University of Stellenbosch. Other partners included South African National Parks, the World Wildlife Fund South Africa, and the Rhino Recovery Fund.
