The coastline
The sandy coastline of the Camargue stretches for about 95 km from the Grau du Roi to Fos sur Mer. Its sinuosity and variable width are witness to a strong erosion caused by both the mistral and the Mediterranean Sea. The dunes of Beauduc in the east and those of l'Espiguette in the west offer large beaches of fine sand whose width can reach up to 1 km. Between these two points, the beaches of Saintes-Maries-de-la-Mer and Salins de Giraud tend to recede, subject to attacks from the Mediterranean Sea. Marine incursions have created in places «graus»: narrow waterways connecting the inner lagoon to the sea.
The famous Espiguette beach
The Espiguette beach is undoubtedly one of the most beautiful beaches in the Mediterranean. It extends over 18 kms and remains a completely wild natural space. It consists of white dunes that are characteristic of deserts and can reach a height of 12 m in some places. It is home to a fauna and flora that can withstand this sandy, very dry and salty environment. However the rise in sea level weakens these dunes, which man tries to consolidate and protect thanks to «ganivelles»: palisade of wooden stakes. The beach of Espiguette is appreciated by all, tourists and locals, for its dimensions that make you dream and its wild side. It is like a piece of desert lost at the end of the world.
Lagoons and salt marshes
The Camargue lagoons are made up of many shallow salt water ponds that naturally communicate with each other but also with the sea by graus. They are mainly located south of the Vaccarès pond. Lagoons are subject to many variations in water level and salinity under the influence of the wind. The mistral (northerly wind) causes the Vaccarès pond to have little salt water in the lagoons, thus reducing the salinity of the lagoons. Conversely, when the sailor (south wind) blows, he favours the incursions of seawater in the ponds, whose salinity increases. In summer, some lagoons dry up partially, leaving room for the European on the edge of the ponds. These glowing steppes in autumn remain poor in flora. Only a few plants that enjoy salt can grow here, such as salihorn or salad (sea lavender). The shallow lagoons have contributed to the development of important biodiversity. They play the role of nursery for many marine fish such as sea bream or eel but also serve as feeding areas for wading birds such as the flamingo.
The production of sea salt
Since ancient times, the lagoons have been gradually transformed. Today these are totally artificialized environments: the water bodies have been geometrically redesigned and their water function is regulated for the production of sea salt. There are two types of pools: salt pans and saunas. The salines are shallow (30 to 50 cm) pre-concentration basins, which are supplied with seawater by pumping. They are dried in the spring and fall. Aquatic plants are rare, unlike algae, which abound and thus provide an abundance of food for many birds and waders. As a follow-up to the salt pans, the salt tables are basins in which crystallization and salt harvesting take place. It is deposited during the dry season thanks to the combined action of wind and heat. These highly saline seawater basins limit the flora to a single species, the red algae Dunadiella salina, and the aquatic fauna to a small crustacean, Artemia salina. The proliferation of these two species colours the water in dark pink. The high carotene content of their pigments is also responsible for the pink colouration of the plumage of the flamingos, the crustacean Artemia salina being the basis of its diet.
Ponds and reed beds
The ponds occupy 25% of the territory of the Camargue, the largest of them being that of Vaccarès with its 6,500 ha. They are supplied with fresh water or very little salt thanks to the «roubines»: irrigation canals of the Rhône, and are shallow (maximum 2 m for the Vaccarès pond). The ponds play a major role for the Camargue ecosystem, in fact they are both a place of reproduction and rest for many migratory birds and a place of life for flamingos. Thousands of ducks come here to rest during the winter and many birds, like the purple heron, come to breed.
Freshwater marshes benefit from dense vegetation. They are mainly invaded by reeds, which develop spontaneously on the outskirts of the ponds, sometimes covering them entirely. They are thus called reed beds. One of the largest reed beds in Europe is located on the banks of the Scamandre ponds where it has been present for centuries on nearly 3,000 ha. The cutting of the reed or «sagne», operated for the roofs of traditional houses, allows the maintenance and rejuvenation of the reed bed.