Our oyster nurseries

Our nurseries play a crucial role in the continuation of breeding. They receive the spat from the micro-nursery. From this point on, the breeding takes place in outdoor basins with seawater that is no longer filtered or heated. Growth becomes dependent on weather conditions.

Similar to their natural habitat, the growth of oysters is subject to weather conditions. In our nurseries, oyster spat is placed in sieves within concrete basins, which are filled with water (raceways). Operating in a closed system, seawater passes through the sieves before being pumped back to the reservoir and recirculated through the sieves again. Our teams provide daily doses of natural phytoplankton (Skeletonema costatum), cultivated to supply the necessary food for the oysters' growth. Partial seawater renewal occurs weekly through channels in the Polder.

The spat is regularly washed in sieves and sieved every two weeks to make the batches more uniform. Due to the growth differences within the same spawn, it's essential to separate the larger oysters from the smaller ones to limit competition: the larger ones filter much more phytoplankton, disadvantaging the smaller ones.

The spat gradually grows from a size of 1 mm to that of T8 (retained on a grid with square meshes of 8 mm on each side). As they grow, the oysters take up more space, requiring more sieves for the same quantity. At this stage, a portion of our production is shipped to our clients, while the rest is placed in bags for pre-growing on tidal flats in Normandy, Brittany, and on the island of Jersey, or in lantern nets (pearlnet) in the Étang de Thau.