The Sundarbans Estuarine System (SES) is a mangrove dominated monsoonal, macrotidal estuarine system in the east coast of India and is one of the best nursery grounds for shellfish populations in this region. The early developmental stages of penaeid prawns prefer the estuaries to complete their bipartite lifecycle. The present study, conducted within the extremely difficult and challenging environment of the SES, is a pioneering attempt to decipher the probable diel and selective tidal variation patterns of different stages (mysis, decapodite and juvenile) of Metapenaeus dobsoni in the SES, India. The observations were conducted by selecting a time series sampling protocol of 72 hours each, during the spring and neap phases of the tidal cycle in the peak monsoon month of August 2014. During the spring and neap tides, the total population was observed to be dominated by juveniles (83%) and mysis larva (61%) respectively. The maximum abundance was observed to occur during the night time of the neap phase irrespective of tidal amplitude. During the spring phase the maximum abundance was recorded at low tide conditions irrespective of the diel variations. The increase in the abundance of mysis stages always synchronized with low tides during the neap phase whereas, the peak increase of juvenile abundance synchronized with the ebb currents (low tides) during the spring phase. M. dobsoni utilize the tidal currents for their ingress and egress mechanisms in order to travel horizontal distances or remain in their preferred habitats. Our study corroborated the significant importance of ontogenetic diel and a tidal variation of larval and juvenile’s abundance in the water column at SES. Such studies of the larval dynamics are very essential in the SES for estimating the fishery potential and sustainable management of wild seed collections by the local fishermen community.

孙德尔本斯河口系统 (SES) 是印度东海岸一个以红树林为主的季风大潮河口系统，是该地区贝类种群的最佳育苗地之一。对虾的早期发育阶段更喜欢在河口完成它们的两部分生命周期。本研究是在 SES 极其困难和具有挑战性的环境中进行的，是破译Metapenaeus dobsoni不同阶段（糠虾、十足目和幼鱼）可能的昼夜和选择性潮汐变化模式的开创性尝试。在印度 SES。在 2014 年 8 月季风高峰期的潮汐周期的春季和小潮阶段，通过选择每个 72 小时的时间序列采样协议进行观察。在春季和小潮期间，观察到总人口占主导地位分别由幼虫 (83%) 和糠虾幼虫 (61%) 产生。观察到最大丰度发生在小潮阶段的夜间，而与潮汐幅度无关。在春季阶段，无论昼夜变化如何，在低潮条件下都记录了最大丰度。在小波阶段，糠虾阶段丰度的增加总是与低潮同步，而在春季阶段，幼鱼丰度的峰值增加与退潮（低潮）同步。M. dobsoni利用潮汐流作为它们的进出机制，以便在水平方向上移动或留在它们喜欢的栖息地。我们的研究证实了个体发育的重要性以及 SES 水体中幼虫和幼虫丰度的潮汐变化。此类幼虫动态研究在 SES 中对于估计当地渔民社区对野生种子收集的渔业潜力和可持续管理非常重要。