The Aldabra Atoll is the second largest atoll in the world behind the Kiritimati atoll. It stretches 21.1 miles long and 9 miles wide. The Aldabra atoll is 26.2 feet above sea level and has a land area of 96.5 miles. The lagoon stretches 139.1 miles across; much of the lagoon will be exposed during low tide. The Aldabra Atoll includes a ring of four larger islands: Grand Terre, Malabar, Polymnie, and Picard, and a few smaller islands. The islands have no inhabitants apart from a small staff of rangers. The atoll accounts for the largest population of giant tortoises. Additional wildlife includes: hammerhead sharks, barracuda, green turtles, hawksbill turtles, mantarays, and various birds.