Dehorning reduces rhino poaching.
Kuiper T., Haussmann S., Whitfield S., Polakow D., Dreyer C., Ferreira S., Hofmeyr M., Shaw J., Bird J., Bourn M., Boyd W., Greeff Z., Hartman Z., Lester K., Nowak I., Olivier I., Pierce E., Rowles C., Snelling S., van Tonder M., Worth E., Zowitsky H., Milner-Gulland EJ., Altwegg R.
Across 11 southern African reserves protecting the world's largest rhino population, we documented the poaching of 1985 rhinos (2017-2023, ~6.5% of the population annually) despite approximately USD 74 million spent on antipoaching. Most investment focused on reactive law enforcement-rangers, tracking dogs, access controls, and detection cameras-which helped achieve >700 poacher arrests. Yet we found no statistical evidence that these interventions reduced poaching (horn demand, wealth inequality, embedded criminal syndicates, and corruption likely combine to drive even high-risk poaching). By contrast, reducing poacher reward through dehorning (2284 rhinos across eight reserves) achieved large (~78%) and abrupt reductions in poaching using 1.2% of the budget. Some poaching of dehorned rhinos continued because poachers targeted horn stumps and regrowth, signaling the need for regular dehorning alongside judicious use of law enforcement.