evidence: Tromelin Island, once called the Isle of Sand, is a low, flat island in the Indian Ocean about 500 km north of Réunion and about 450 km east of Madagascar. Tromelin is administered as part of the French Southern and Antarctic Lands, a French Overseas Territory, but Mauritius claims sovereignty over the island. Tromelin has facilities for scientific expeditions and a weather station. It is a nesting site for birds and green sea turtles.