Interestingly, Linckia laevigata populations found in the wild consist almost entirely of adult individuals. The adults of L. laevigata reach a maximum size of 30cm in diameter and based on the data from previous research studies, mean arm length of the blue sea stars increases with increasing depth (Thompson & Thompson 1982; Strong 1975).
With regard to the population occurring on the Heron Island Reef, size
of the adult blue sea star generally exceeds 20cm (Laxton 1974). The
central disc diameter of the Heron Island population ranges from
approximately 30mm to 40mm, and the arm length of the blue sea star
varies from about 80mm to 120mm (Laxton 1974).