A propos des problèmes de captage de naissain de moules (Mytilus edulis L.) dans le Pertuis Breton de 1989 à 1991 : observations préliminaires

A retrospective study has been carried out on the possible relationships between the spat recruitment of mussels from the Pertuis Breton (France) and some environmental factors at different periods of the year. A significant negative correlation between recruitment and temperature has been found at two periods of the reproductive cycle; the first one coinciding with gametogenesis and the second one taking place just before spawning. But, no relation was noticed with temperature or salinity during the plantonic stage. These results are discussed. An interesting relationship was found between recruitment and "E.T.P.", an index expressing the drying power of air, taking into account temperature, wind, sunshine and moistness. Dessication appears to be important when the larvae collectors are submitted to long periods of emersion, during spring tides. Nevertheless, specific studies might be undertaken in order to precise the resistance of mussel spats to drying, according to their age and the importance of this process (intensity and duration).