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A hydrodynamic model was coupled to a particle tracking model to examine physical factors that influence transport of the white croaker larvae in the Ariake Sea, Kyushu, Japan. The idealized particles that mimic the larvae of white croaker are tracked under various physical and biological conditions. Freshet reduces the possibility of particles that reach the nursery ground around the head of the bay by 7 % on average. Spring tide has a positive impact on the feeding migration of particles. Selective tidal stream transport (STST) mechanism dramatically changed particle trajectories. Particles tend to reach the shallower nursery ground easier during ebb or low tide rather than high or flood tide, depending on whether the STST is considered during the particle tracking experiment. In particular, the ratio of the number of particles that reach the nursery ground increases by approximately 24 % from flood tide to low tide. When the sinking velocities of particles, ranging from 10-5 to 10-3 m/s, are considered during the particle tracking experiment, majority of the particles stayed in the releasing area., 海洋数値シミュレーションモデルと粒子追跡モデルを用いて，物理的要因が有明海の仔魚輸送に及ぼす影 響について調べた。モデルにおいて仔魚は仮想的流体粒子として表現される。河川水の出水は生育場へ輸送 される粒子数を７%減少させる。大潮時に潮流流速が増すことによって，生育場へ輸送される粒子数は増加 する。稚魚の鉛直移動の効果（Selective tidal stream transport）によって，粒子の輸送過程は大幅に変化 する。干潮時や下げ潮時に投入された粒子は，より生育場へ到達しやすくなる傾向がある。10-5から10-3m/s の範囲で粒子の沈降速度を加味した場合，粒子は放流地点付近にとどまる傾向が強くなる。, 長崎大学水産学部研究報告, 93, pp.19-32; 2012