Site details

Marennes-Oleron Bay
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              Candidate Reference Site

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Synoptic description of site:

Located half way along the French Atlantic coast, this is a macrotidal embayment of ca 200 km² dominated by large intertidal mudflats and protected from the direct oceanic influence by the Oléron Island.


Habitat description:

The area contains large intertidal mudflats of which lower parts are devoted to oyster and mussel farming activities. Very few sandy beaches or rocky shores exist.


The Marennes-Oléron bay is pristine with respect to industrial waste inputs. Results from IFREMER water quality network (RNO) can be consulted on the IFREMER web site (


Researchs on marine biodiversity are facilitated by the occurrence of several laboratory around the bay i.e. CREMA (CNRS-IFREMER) laboratory and the LBEM (Laboratoire de Biologie Marine) since 1995 at the University of La Rochelle.

Available database and website:

Available macrofauna biodiversity information have been recently reviewed by de Montaudouin & Sauriau (2000). Biodiversity studies were foccussed on zooplankton, macrofauna and fish species. Most recent studies are involved in nematods assemblages in collaboration with MNHN (Guy Boucher).


Additional Information:

Web site of CREMA : A web site on marine biodiversity at CREMA is under construction. The most up-to-date information about marine biodiversity in the area concerns the occurrence of the Japanese drill Ocinebrellus inornatus (Recluz, 1851) in the bay since 1995 (Pigeot et al., 2000). This was the first record of the species in Europe and its occurrence could be linked to shellfish activities. Reference : de Montaudouin & Sauriau (2000) Contribution to a synopsis of marine species richness in the Pertuis Charentais Sea with new insights in soft-bottom macrofauna of the Marennes-Oléron Bay. - Cahiers de Biologie marine, 41 : 181-222. Pigeot J., Miramand P., Garcia-Meunier P., Guyot T. & Séguignes M., (2000). Présence d'un nouveau prédateur de l’huître creuse, Ocinebrellus inornatus (Récluz, 1851), dans le bassin conchylicole de Marennes-Oléron. Comptes Rendus de l’Académie des Sciences Paris, 323 : 697-703.