Bay of Marennes-Oléron (French Atlantic Coast)
The Bay of Marennes-Oléron is located on the Charentes Maritimes Atlantic coast of France, slightly north to the Gironde Estuary, within the so-called Pertuis Charentais.
The bay is limited in the north by a line linking the Fort Boyard, Aix Island and the Charentes Estuary, in the west by the Pertuis d'Antioche, at the South by the Oléron Island and the Pertuis de Maumusson and on the east by the French coast. The Charente River and the Seudre River flow in the bay which is shallow with sandy, silty and/or muddy bottom coverage. The sea bed has a gentle and regular slope. The bay experiences a strong dynamic of barotropic currents which are tide driven. The spring tide amplitude is 5.4 m. The tide amplitude and the tidal currents may be affected to a certain extent by meteorological factors such as wind and pressure (storm surge). The many mouths of the bay as described above render the current pattern in the bay quite complex.
The coast is very low and in several places protected by dykes which may be threatened by a possible coincidence of spring tides and storm surges.
The intertidal flats are extensive and these shallow seas are a fragile ecosystem. These areas are particularly sensitive to the nutrients which are brought by the inland rivers flowing into the bay. These intertidal flats are used for intensive oyster and mussel culture.
In addition to aquaculture, the economic activity of the bay includes the industrial harbour of Rochefort, the fishing activities of the bay and the tourism which is highly developed in summer in particular on the Oléron Island which is now linked to the coast by a bridge.
Special emphasis within OPCOM will be laid on questions concerning the impact of natural and anthropogeneous changes on the ecosystem of the bay, in particular management of the nutrient situation for a sustainable oyster farming activity.
For further information please contact Cedric Bacher (Cedric.Bacher@ifremer.fr) or Catherine Freissinet (catherine.freissinet@sogreah.fr).
Other OPCOM investigation areas: