Bay of Seine, bay of St. Brieuc and the rade of Brest are the three main fisheries in France. Measurements made on spawners issued from these areas allow to consider two separate reproductive strategies, in these populations. Scallops from St Brieuc spawn during a short period, a sexual rest stage being observed in autumn and winter and recovery occurring in spring. Populations from Brest and from bay of Seine show similar reproductive cycle with a permanent annual sexual activity spawning being scattered from early spring to autumn. This reproductive strategy could explain that recruitment in these fisheries are better than in St Brieuc bay. The variations of the muscle and gonad index are opposite. The muscle acting as storage organ releasing metabolites to cover the energy requirements for growth and reproduction.