DIZANGUE – Ever since his first hard-won sightings of African manatees, award-winning marine biologist Aristide Takoukam Kamla has been devoted to protecting the little known and atrisk aquatic mammals.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…