For over a century, the salt workers of Camargue have been creating vast basins to extract salt from seawater. These basins, first developed in the 19th century, were originally built for industrial purposes. However, they have unintentionally become a vital habitat for water birds, including the iconic pink flamingos that gather in the Fangassier pond. This area has become a symbol of the Rhône delta’s unique natural beauty. The color of these salt basins ranges from green to intense red, depending on their salinity. The more saline the water, the redder it becomes, due to the presence of a microscopic algae called Dunaliella salina, which produces beta-carotene, a red pigment. Pink flamingos get their distinctive pink color by feeding on tiny shrimp called Artemia salina, which live in the saltiest parts of the basins and accumulate this red pigment. The saltworks of Salins-de-Giraud were established in 1855 in the western part of what would become the largest salt production area in Camargue. Starting in the late 1950s, the company undertook major construction projects to convert natural lagoons and marshes in areas such as Vaisseau, Beauduc, Rascaillan, and Fangassier into evaporative basins. The goal was to reach an annual salt production of one million tons. The process is simple in principle: seawater is pumped into the first basins, called partènements, where the salinity is around 38 grams per liter. As the water moves through a series of basins—sometimes over dozens of kilometers—its salt concentration gradually increases. Eventually, the water reaches the salting tables, or crystallizers, where the salinity reaches 260 grams per liter, just before salt begins to crystallize on the surface. The salt is never pumped; it is left to dry naturally. The colorful palette of the basins, ranging from green to red, is not just a scenic backdrop—it is a clear indicator of salinity. Basins with lower salinity appear green due to the presence of green algae. As the water becomes saltier, the color shifts from pale green to intense red, thanks to the algae Dunaliella salina. This algae produces beta-carotene, a pigment that protects its DNA from the harsh summer sun. The same pigment is found in carrots and is passed up the food chain to the tiny shrimp Artemia salina, which thrive in the saltiest basins. Pink flamingos feed on these shrimp, and the red pigment accumulates in their feathers, giving them their characteristic pink color. However, young flamingos are born white, and their pink color only develops through this process. Without the salt basins, the algae and shrimp would not exist, and the flamingos would never develop their iconic pink plumage. Between 2008 and 2012, the Conservatoire du littoral, a French public body dedicated to protecting coastal areas, purchased 65 km² of land from the salt company—equivalent to over 9,000 football fields. In partnership with local organizations and NGOs, the Conservatoire has worked to restore and renaturalize the salt basins. Major hydraulic projects have reconnected ponds to the sea and sub-basins, while artificial islands have been created to support the nesting of various bird species. Today, the Camargue salt site is home to a wide range of natural environments, including coastal habitats, lagoons, salt marshes, and dunes. The high dunes of Beauduc and the Fangassier pond remain key nesting areas for pink flamingos. The Camargue Regional Natural Park’s charter ensures that salt farming continues in a way that preserves the diversity of these basins, which are crucial for birdlife. Flexible dikes and central rafts—structures originally designed for salt production—are maintained to provide resting and nesting areas for birds. Without this industrial knowledge, the basins might dry up or reconnect to the sea, which would jeopardize the habitat of the pink flamingos.