The Pygmy Hippo: A Very Secret Life (S33E05)

The pygmy hippo is one of nature's last great mysteries. Solitary, secretive and extremely hard to find, scientists know almost nothing about this endangered animal in the wild and what it needs to survive. Now, a young Australian ecologist, Wei-Yeen Yap, is taking on what could be 'mission impossible'. In a remote West African rainforest, Wei investigates the secret life of the pygmy hippo, attempting to unravel its mysteries in the hope that with greater knowledge we will be able to save it. (BBC)