As long as it is illegal to farm rhinos for their horns and to sell the stuff on the open market, poaching will continue until extinction. Rhino horn can be harvested completely benignly (with the administration of a little tranquiliser), just like shearing a sheep.

When rhinos go extinct, it will be entirely the fault of the conservationists who are wittingly or unwittingly supporting the cartels in their highly lucrative illicit dealings.