The intentional establishment of the Japanese oyster Crassostrea gigas (Thunberg) in replacement of the Portuguese oyster caused numerous biological problems. The possible introduction of some Turbellariae, oyster predators, was at the origin of the regulation concerning the "stay in freshwater" of the spat. The implantation of other microorganisms drew our attention. Our results, though fragmentary, show that some Japanese species live on our coasts (Bay of Bourgneuf and Traiet du Croisic) a year after the immersion of the original collectors: Annelida Hydroides ezoensis, Cnidarian Aiptasia pulchella, Mollusc Anomia chinensis, Cirripedes Balanus amphitrite amphitrite and Balanus albicostatus. The survival chances seem to vary according to the oyster... |