Determining age is an important step when assessing growth, mortality, and yield of
cultivated and wild populations, but studies linking shell growth marks in the pearl
oyster Pteria sterna with the age of individuals are lacking. Thirty
juveniles (20.0 ± 1.2 mm shell height), collected from a winter spatfall, were marked with
the fluorochrome calcein and kept in the field in culture containers. After day 16, the
juveniles were cleaned and their shells cut along the sagittal axis to determine
periodicity of micro growth bands formed in the inner shell layers and to estimate age.
During this trial, fluorescent calcein marking succeeded in individuals larger than 20 mm
shell height; these formed an average of 15 micro growth bands over the 16 days,
representing 1 band per day. The marker created a wide fluorescent band containing three
micro growth marks, suggesting that calcein was incorporated into the shell over the first
three days. The use of calcein was found to be an accurate method for validating the micro
growth band frequency of formation in P. sterna juveniles, which in turn
can help to estimate age.