Owned by the Conservatoire du Littoral since 1982, the Mousterlin polder is managed by the community of communes of Pays Fouesnantais.
The story of the swamp
In 1926, the Prefect of Finistère granted a dike concession to Mr. Bénac. Ten years later, the total closure is achieved and some 120 ha of marsh are removed from the direct influence of sea water.
The last work, completed in 1930, is the dyke with a large system of valves which is located in Mousterlin, at the old place of the gully.
The willows carried out a rapid conquest of the environment since in 1954, the polder was practically bare except for a barrier of poplars and tall pines at the foot of the coastal strip. Behind, the landscape was especially marked by an impressive sowing of cider apple trees.
The screen of willows gradually withers to make way for a beautiful phragmitaiia. Phragmites is a marsh reed and ditches used to make thatched roofs. Willows, Phragmites, pines and oaks quickly replaced wet meadows.
Owned by the Conservatoire du Littoral since 1982, the Mousterlin polder is managed by the community of communes of Pays Fouesnantais. This acquisition made it possible to undertake work without which the site would have become an inextricable maquis of willows.
Draining and thinning the vegetation were therefore the priority tasks to recreate the landscape. More recently, and given the damage caused by the 1987 hurricane, plantations have been carried out.
The Conservatory has chosen to let the polder operate as it did a few years ago, when seawater came in naturally due to the dilapidated state of the valves. The brackish lagoon acts as a nursery for fish and some crustaceans.