In the oceans of West Africa, it's a poachers' paradise. Foreign ships are illegally raiding these rich fishing grounds, leaving little for locals. Now the tide is turning, as activists help governments push back the boats.

The mighty Colorado is under threat. From the Rockies' snowy peaks to Mexico, the river is a lifeline for tens of millions of people. We journey along its waters to see places and meet people changed by a drier world.