In 2002 a highway was paved between the capital of Maranhão, São Luís, and Barreirinhas, a rapidly growing country town that now promotes itself as the entry point to the park. Since then, tourism has also increased, with more than 60,000 park visitors a year now, and joyriding on the dunes on all-terrain vehicles has become a big concern for park officials.
"Vehicles are forbidden on the dunes," says Alvite, who worries that such reckless activities pose a threat to migratory sandpipers and terns as well as the birds that nest there. In an effort to promote a more sustainable kind of tourism, she led a group in 2009 on a 40-mile hike from one side of the park to the other to look for signs of dune creatures, including the Brazilian slider turtle (Trachemys adiutrix), the yellow armadillo (Euphractus sexcinctus), and the white-eared opossum (Didelphis albiventris).
It's no wonder that outsiders want to visit this otherworldly place, the largest coastal dune field in Brazil. Even those who know it best are surprised by its constantly shifting beauty. Manoel Brito, the late patriarch of Queimada dos Britos, used to keep a herd of 500 or so goats that roamed freely through the sands. Wandering over the dunes with his herd, he would marvel at the way the sands kept on the move. "Everything here always looks the same," he once told me. "But every day, if you look carefully, you'll see that the sand is in a different place. God created these white mountains and made the wind play with them forever."