response to the government program in Selangor, the national cockle production decreased and has stagnated at a low level (DoF Malaysia 2001. The reason for this collapse is still unknown. Therefore, to improve aquaculture efficiency, biologically suitable culture plots should be chosen for the species to concentrate cockle spats and human efforts. If the cockles signal about a place suitable for their growth and survival, this information could be used to design culture plots more efficiently.Our previous study proposed two indices to assess the long-and short-term growth of blood cockles, which are the adjusted sharpness index (SI adj ) and the estimated condition factor (CF), respectively (Saito & Teoh 2020). The biggest advantage of the new indices is that they can