More than 60 per cent of the world’s elephants were killed by poachers in the 1970s and 80s. Since then an international ban on the ivory trade has helped herds recover. But new evidence is emerging that poaching is again on the rise. Now investigators are using a new DNA technique to identify the killing fields. Earth Report follows the trail from Africa to the US and Japan. Duration: 22 Minutes Formats available : DVD Read Less