Saving the mysterious African manatee at Cameroon hotspot

African manatees are found in fresh water along the coast of western Africa, such as in Cameroon's vast Lake Ossa where the researcher first saw them more than 10 years ago. But they are shy creatures -- spotting them requires setting out before dawn when the lake is glassy and tranquil, all the better for following the trails of bubbles and, maybe just maybe, catching two big nostrils taking a quick breath. "I was expecting to see them like on YouTube: in clear water, jumping like dolphins......