. >> daljit: tom de meulenaer is the coordinator of the united nations programme to monitor the illegal killing of elephants. >> tom: we are losing the battle of african elephants in central africa. >> daljit: the elephant tusks are smuggled out of gabon as part of a vast international network of traffickers. the ivory is headed largely to asia where it's used for decorative and other purposes. the thirst for these products globally is so great that the illegal trade of ivory products reached record levels in 2011 with an annual value of some 100 million us dollars according to un estimates. it is feared that as many as 12 thousand african elephants may be slaughtered every year for their ivory. and although a protected species, in the last three decades, the elephant population in africa has been more than halved - something joseph cannot accept, no matter the personal cost. >> joseph: it's a thankless task, not well paid - a very difficult work, but i don't think there's any alternative. >> daljit: and now, the "elephant man" is travelling 4 hours up the river ivindo to a remote corne