Commercial clam hatcheries require a method of labeling or "tagging" clams so that they can be identified as hatchery reared. This is a requirement of the Queensland Department of Primary Industry, aimed at the prevention of the sale of clams collected illegally from the Great Barrier Reef Marine Park. Methods used for tagging to date have been labor intensive, therefore expensive, and suitable only for sales of small numbers of animals.
This study developed a cheap and relatively easy method of labelling commercially reared clams using a dye which stained the organic matrix of the shells. This dye, Erythrosine B, colours the organic matrix of the shell periphery a bright pink which remains in a band as new shell is laid down. The new shell is not discoloured. The dye meets all the criteria which the project identified as desirable for a chemical tag.