Cutting off rhinos' horns is a contentious last resort to stop poaching. A new study found it works

FILE -- In this file photo taken Feb. 15, 2016, a de-horned rhino and her calf rest in their corral at a rhino orphanage in the Hluhluwe-iMfolozi Game Reserve in the KwaZulu Natal province South Africa. (AP Photo/Denis Farrell-File) The Associated Press

CAPE TOWN, South Africa -- Cutting off the horns of sedated rhinos with a chainsaw has been viewed by wildlife conservationists in Africa for more than 30 years as a necessary evil to save the iconic endangered species from poaching.

They hoped the drastic action was working, but evidence was scarce.

Now, a study published Thursday in the academic journal Science has found that dehorning rhinos has led to a large reduction in poaching in game reserves in and around the Kruger National Park in northern South Africa — an area that's