A NUMERICAL ANALYSIS OF THE BEHAVIOR OF PLANKTONIC LARVAE OF MANILA CLAM IN HAKATA BAY

Abstract

 We studied the comparison between the floating larval behavior of Manila clam with the difference of the season in Hakata Bay by using numerical simulation. As a result, we appreciated the following. (1) The characteristics of the distribution and the characteristic of the floating larvae transferred in the bay were different by the flow around the spawning field and the surface seawater flow with the flood. In addition, many floating larvae were flown to outside of the bay at the time of flood compared with normal stage of water, and the larval numbers supplied to each habitation field were decreased. (2) The Manila clam quantity of natural resources was changed by the growth and survival of larvae, which were born in spring and fall with a few floods, after the settlement on the sea bottom. (3) The natural resources and the number of larvae which supplied to the western area of the Bay could be increased by keeping the habitation field located in the central area in good condition and increasing quantity.