Population dynamics and metabolism of Aequipecten opercularis (L.) from the western English Channel (Roscoff, France)

Population dynamics of the queen scallop, Aequipecten opercularis, was investigated in the western English Channel off Roscoff. Annual formation of natural growth rings on the shell surface was validated by stable isotope (δ18O and δ13C) analysis. A von Bertalanffy growth function (Ht = 58.9 mm • (1-e−0.604• (t +0.235))) was fitted to size-at-age data of 249 individuals. Annual somatic and gonad production amounted to 19.74 kJ m−2 and 0.98 kJ m−2 y−1, respectively. Total mortality rate Z was estimated to be 1.716 y−1. Net growth efficiencies (ranging from 45% in 1-y-old to 11% in 6-y-old individuals) were in the same range as in other short-lived scallops. Individual growth, however, was distinctly slower in this population than in other A. opercularis populations from similar latitudes, most likely due to a more stressful environment.