Allowing seized and farmed rhino horn to be traded to fund conservation measures will simply encourage more poaching, says Richard Schiffman

Avalon/Photoshot License / Alamy Stock Photo

A battle is brewing over rhino horn in South Africa. This week, the Convention on Trade In Endangered Species (CITES) shines a spotlight on the alarming decline in rhino numbers.

From half a million animals at the beginning of the 20th century, there are 29,000 surviving today, most in southern Africa and in fragmented enclaves in Asia. Three of the five remaining rhino species are critically endangered due to increased poaching, fuelled by a doubling in the illicit horn trade since 2013.

As the 181 nations that make up CITES meet in Johannesburg, …