A comparison of growth and biochemical composition Mytilus galloprovincialis (Lmk.) and Mytilus edulis (L.) on the West coast of Cotentin, Normandy, France 1999-2000

The blue mussel, Mytilus edulis has been reared along the Normandy coast line since the 1960s. The gonadal cycle of this mussel species shows a sharp decrease in meat quality during the winter period after spawning. This decline in meat quality is so severe that sales have to be suspended from December to July. Another species of mussel, Mytilus galloprovincialis, which is reared in the lagoons along the French shore of the Mediterranean Sea has a different spawning cycle. An experiment was undertaken to study the meat quality of M. Galloprovincialis throughout the year after the spat were transferred from the Mediterranean Sea to the Normandy coast. This species showed an immediate adaptation to the gonadal cycle of M. edulis. Despite suggestions from researchers, no interest was expressed to consider such transfers of M. galloprovincialis in the future.