Mine disaster threatens small dolphins

Conservationists and engineers in Brazil are battling to save marine wildlife from contamination following the collapse of a dam, which has led to the waters in the Rio Doce estuary to turn brown with toxic mud.  

After the dam’s collapse, water containing iron-ore residue from the nearby Samarco mine entered the delicate ecosystem of the river, which flows out in to the Atlantic. The area is rich in marine life, including humpback whales and one of the world’s smallest dolphins, the franciscana.