The Seudre marshes, which thus form a structuring component of the communal landscape, have a unique appearance, made up of mudflats with grey-blue reflections, punctuated by reed hedges and wild grasses. In the commune, they are delimited by the Seudre itself, with the Mouillelande bank which forms the boundary with Le Gua, its tributary the Liman, but also by the channels of Coulonges (administrative boundary with Chaillevette), Téger, Mornac (along which is the port), Plordonnier, Agnoux and Fontbedeau. Mornac being part of the Marennes-Oléron oyster basin, they are home to numerous oyster beds, or "claires", refining basins where the oysters acquire a particular flavour and colour under the action of a pigment (marennine) produced by a microscopic algae called blue navicula. From Roman times to the 18th century, the Seudre estuary and the outlet of the Liman were occupied by saltworks. The commune has rehabilitated this tradition and now preserves a small salt marsh, where salt is harvested in an artisanal way. The marshes are crisscrossed with small picturesque paths and observation posts that allow you to better understand this very rich natural space, where many birds come to stop and nest. Here more than anywhere else, you become aware of the almost island character of the commune, with this subtle interweaving of land and water and an infinite sky, often blue because swept by sea breezes where human activity tries to preserve the existing fauna and flora for the greatest pleasure of all.