The recent killing of a rhino in a Paris zoo marks a shocking new development in this ruthless global trade but rhino experts remain optimistic that the situation can be reversed

A mutilated corpse of a pregnant poached black rhino in the Lewa wildlife conservancy in northern Kenya
A mutilated corpse of a pregnant poached black rhino in the Lewa wildlife conservancy in northern Kenya. Photograph: Dai Kurokawa/EPA