BANC D’ARGUIN NATURAL RESERVE: Since he was old enough to climb into a boat, Samata Mahmoud has been fishing the vast, dune-lined waters of Mauritania’s Banc d’Arguin bay, living a centuries-old lifestyle threatened by climate change and overfishing.

Mahmoud is a member of the Imraguen fishing-based community, a desert people who have spent centuries developing practices in harmony with nature, living in the area where the Sahara meets the Atlantic.

At the first light of dawn the village of Iwik stirs to life, white sails unfurling across the bay’s calm waters.

With motors banned, the only vessels gliding about are “lanches,” small sailboats said to have originated from ancient ties with the Spanish Canary Islands.

Banc d’Arguin National Park, which was designated a UNESCO World Heritage Site in 1989 and is located on Mauritania’s northern coast, is home to some 4,000 Imraguen people, the only population permitted to live within the reserve.