Abstract
In this paper, by analysis of generation structure of population of created from observation results of larvae of the clam Ruditapes Philippinarum in Tokyo Bay, average growth rate and the spawning date of larvae was estimated in a rational manner. We could create a simplified growth model taking into account the individual differences of the larvae of clam Ruditapes Philippinarum in Tokyo Bay, and prove the validity of the growth model reproducing the results of the observations shown in distribution of frequency of appearance of larvae of different shell lengths. Also, we created a vertical movement model taking into account the individual differences with the difference of density between the sea water and the larvae serving as the impetus and proved the validity of this model by conducting a basic vertical reproduction simulation.
