After seven years' study, visiting islands scattered over more than a million square miles of the western Indian Ocean, where once hundreds of thousands of green turtles nested every year, the author?'s “optimistic estimate” of the number of females nesting today is 5500. Only eighty years ago 12,000 were taken in one year on Aldabra alone. Over-exploitation by man for food – both of nesting females and eggs – and destruction of nesting habitat, i.e. disturbance of the beaches, are the two factors that are destroying this immensely valuable resource. The author's study was assisted by FPS.