In the eastern part of the English Channel, common sole (Solea solea) has strong interests in fisheries research. Low recruitment along with a decline in spawning stock biomass have been observed for several years. According to the recruitment hypotheses, larval survival may play an important role that needs to be considered. The fish larval condition can be assessed using histology which has been recognised as the most appropriate method to provide a reliable index of the nutritional status. Based on this approach, this study aimed to identify critical periods of wild-collected sole larvae and to determine sources of variations of their condition between two periods separated by more than 20 years. In line with other studies, the transition from endogenous to exogenous feeding was identified as the most critical period with the lowest proportion of healthy larvae observed. During this first feeding stage, good larval conditions were located in sampling stations close to the coast and at the end of the spring season, in relation to higher temperature and fluorescence values. This highlights the need for sole larvae survival to cross the coastal front, which splits the central and coastal waters, to reach more stable and productive areas. This coastal migration pattern was consistent between 1995 and 2017, with however significantly lower larval abundances in the recent period. Multivariate analyses showed that the spring environmental conditions of 1995, characterised with lower temperature and higher fluorescence values were more favourable to larval condition, compared to the spring in 2017. Areas providing suitable environmental conditions in 2017 were more restricted and limited to sampling stations in front of estuaries. Since small differences in larval survival can lead to large fluctuations in recruitment, the larval condition should be studied in a more long-term approach. This would provide a better understanding of the environmental influence on larval survival and recruitment success.

在英吉利海峡的东部，常见的唯一（Solea solea）对渔业研究有浓厚兴趣。几年来观察到低的募集以及产卵生物量的下降。根据募集假说，幼虫的存活可能起着重要的作用，需要加以考虑。可以使用组织学来评估鱼的幼体状况，该组织学被认为是提供可靠营养状况指标的最合适方法。基于此方法，本研究旨在确定野生收集的唯一幼虫的关键时期，并确定相隔超过20年的两个时期之间其状况变化的原因。与其他研究一致，从内源性喂养向外源性喂养的过渡被确定为最关键的时期，观察到的健康幼虫比例最低。在第一个喂养阶段 相对于较高的温度和荧光值，良好的幼体条件位于靠近沿海的采样站和春季末。这凸显了唯一的幼体生存需要穿越沿海地区，该地区将中部和沿海水域分开，以到达更稳定和生产力更高的地区。这种沿海迁徙模式在1995年至2017年期间是一致的，但是最近时期幼虫的丰度大大降低。多因素分析表明，与2017年春季相比，1995年春季的温度较低，荧光值较高的环境条件对幼虫条件更为有利。2017年提供适宜环境条件的区域更加狭窄，仅限于前方的采样站河口。由于幼虫存活率的微小差异会导致募集的大幅度波动，因此应采用更长期的方法研究幼虫的状况。这样可以更好地了解环境对幼虫存活和募集成功的影响。