The dugong is the only living marine mammal to feed almost exclusively on plants (3), a trait that leads to its other common name of 'sea cow'. These large, rotund animals have short front flippers and a fluke-like tail that is used for propulsion (4). The thick skin is a grey-bronze colour and there are short, coarse hairs sparsely distributed over the body but concentrated as bristles on the muzzle (3). All dugongs grow tusks but these only break the skin, and therefore become visible, in mature males and old females (3). The large, rounded snout ends in a cleft, muscular upper lip that hangs over the down-turned mouth (4).