A pilot study regarding the transplantation of 100 specimens of the critically endangered Pinna nobilis took place in summer of 2019 in Maliakos Gulf (Central Aegean, Greece). In this study we present the relationships between total height (HT, in cm), unburied length (UL, in cm), and shell width (SW, in cm) for P. nobilis and the relationship between HT and net weight (W, in g). Length-length relationships were all linear for all cases: r2 > 0.900), whereas the relationship between HT and W was exponential with the value of the exponent b being allometric. "Ecology, Conservation and Restoration of Threatened Animal"