Île aux Cerfs has no bridge and nobody living on it, so every visit to these eighty-seven hectares of casuarina and white sand begins in somebody's boat. It lies a few hundred metres off the east coast of Mauritius, behind a barrier reef that takes the weight of the Indian Ocean. The water it leaves is flat enough that you can wade a long way out. Boats run all morning from the mainland village of Trou d'Eau Douce, and most take you the long way first, turning up the Grand River South East to idle under a waterfall over black volcanic rock. That water is not local. The river drains the island's high centre, where the trade winds are forced upward and let go of some 4,000 millimetres of rain a year. So the fall comes down hard after the February and March storms and runs thin by winter. At the islet you swim off the sand with a mask. What holds the eye is not the open shallows but where dark basalt breaks through the pale floor and the fish gather over it.
A hotel group runs what there is ashore: restaurants behind the landing beaches, and eighteen holes of golf across the interior, so players cross the lagoon by boat with their clubs. By late morning the day boats have filled that first stretch of sand. From June to September the southeast trade wind pushes onto this coast and stirs sand through the windward lagoon; once it eases in October the surface goes glassy. Past the last restaurant the crowd is behind you within minutes, and the shore turns to bare sand and casuarina with no one on it. The deer have gone the same way. The Dutch brought Java deer to Mauritius in 1639 to keep meat alive for passing ships, and stocked this islet with them; the herd later broke out and spread across the country, where it still runs wild. There has not been a deer here for generations, and the French name, island of stags, is the only part of them that stayed.