Underneath

Most photographs of a hawksbill are of its back. This is its underside, the plastron, the plate a turtle spends its whole life keeping between itself and the sea floor and shows to almost nobody.

The hawksbill is the reef's sponge eater. The narrow beak that names it reaches into crevices no other turtle can, and a diet of sponges leaves its flesh faintly toxic, which is one reason it has few predators once grown.

On this dive at Bunaken the photographer counted twenty-six turtles, and it was this one, rising off the wall on its way to breathe, that passed directly over the camera. The sky behind it is the surface. Bunaken National Park, north Sulawesi.