A sclerochronological analysis on the Mediterranean bivalve Ostrea edulis (Linnaeus, 1758): a quick age determination method

Valves of the ostreid bivalve Ostrea edulis (Linnaeus, 1758) were analyzed by visual sclerochronology based on umbonal ridges and internal growth lines, along with the calcitic chalky lenses deposited below the adductor muscle scars. The lenses are herein proposed for the first time as a tool for a quick age determination. The analysis revealed ages of 5 to 7.5 years, consistent with shells’ dimension. A Von Bertalanffy growth curve, markedly different from published analogous ones, showed that shell height alone is not a valid proxy for age determination. The adopted sclerochronological method is advised for age assessment of oyster settlement on human artifacts on the seafloor