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Stage 19 – Embrun > Salon-de-Provence

The Crau sites

The plain of Crau lies in Provence, between Alpilles and Camargue. It is the last, incredibly fragile, Mediterranean steppe of Europe, and it is the cradle of significant pastoral activity.

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The Crau is the fossil delta of the Durance which has been depositing pebbles taken from the Alpine massifs for 4 million years. When the Durance retreated 75,000 years ago, it left behind this vast expanse of pebbles. This semi-arid steppe is called “Coussoul” locally, which comes from the Latin cur-sorium meaning “route”.

In 1559, the state engineer Adam de Craponne began construction works for canals that would bring water from the Durance to Crau. The canals also transported fertile silt which made the soil suitable for planting quality grassland, which now has a “foin de Crau” (“Crau hay”) controlled designation of origin (AOC) label.

Unrivalled wildlife richness

As an outpost of the steppes of North Africa, the Crau shelters a great original biological richness. The figures speak for themselves: out of 470 bird species observed in France, 300 are found in Crau. The site is also the only French station of the pin-tailed sandgrouse!

It also hosts a large part of the French population of certain species of birds such as the little bustard, the lesser kestrel, the calandra lark and the Eurasian stone-curlew.The Crau does not lack insects with its 500 species of butterflies and 40 species of grasshoppers and locusts.

Among these species, the Crau plain grasshopper, which is in critical danger of extinction, is an endemic species of the Crau: it is not found anywhere else in the world! Even though it is the biggest cricket in France, it is a camouflage master: on average, it takes an observer two hours to spot it on a 9 m² surface!

Moreover, the Vergière canal is internationally renowned for the 49 species of dragonflies (out of 80 species in France) that gather there.

A plain under pressure that justifies the protective measures

Of the original 60,000 ha of the Crau plain, only 8,500 ha of virgin Coussouls remain, the last vestiges of a steppe that cannot regenerate due to a disturbance of the soil as a result of crops and development. However, this strong decline has led to a strong desire to preserve this high-quality area.

  • Natura 2000 sites: this Crau preservation perimeter extends over more than 43,000 ha of Crau's Coussouls and hay meadows. It aims at maintaining the habitats and species of the Crau in a good state of conservation, while taking into account the social, economic and cultural aspects of the territory;
  • a national nature reserve called “Coussouls de Crau”: it was created in 2001, and this protection area with a large regulatory scope covers nearly 7,500 ha of virgin or degraded Coussouls. It has been co-managed since 2004 by the Conservatory of Natural Areas of the Provence-Alpes-Côte d'Azur region and the Chamber of Agriculture of the Bouches du Rhône. In addition to being a protection zone, the reserve is also a territory of experiments, inventories and scientific monitoring to improve knowledge and adapt the management of the territory.