2024 Volume 80 Issue 17 Article ID: 24-17245
Hard clams (Merterix lamarckii) are an important fishery resource fished in Japan. However, the catch amount fluctuates widely from year to year, and in some areas the amount is zero. Therefore, the relationship between the physical environment during the spawning and floating periods, which are important for the survival of hard clams, and the catch amount was examined using the FORA and results of long-term wave hindcast based on JRA-55.
For the spawning of hard clams, low water temperatures and the occurrence of coastal upwelling are important factores, and a flow environment that allows the larvae to settle on the bottom is necessary. The favorable water temperature and current environment must continue for several years in order to increase the catch amount of the hard clams. The low catch on the Miyazaki and Ishikawa coasts may be due to high water temperatures, low occurrence of coastal upwelling, and a lack of suitable flow environments during spawning season.
