Abstract Pachygrapsus marmoratus is a common coastal crab occurring in rocky shores of the northeastern Atlantic. The species presents a planktonic larval phase, constituting an interesting subject for dispersal studies, given the larval release in intertidal areas, followed by the exportation to shelf waters where larval development takes place. Onshore migration to the adult habitats is thought to be performed by the megalopa stage. Observations obtained during a summer zooplankton survey showed P. marmoratus larvae gradually farther from the coast throughout larval development, with early larval stages found in surface layers and megalopae occurring closer to the coast. The vertical migration mechanisms for larval dispersal and the return to settlement habitats were tested through physical-ecological models where the vertical distributions changed through the larval development. Ecological data, such as the ontogenetic vertical distribution of each larval stage, larval duration, and time and sites of spawning, were integrated in an oceanic model. Simulations tested different vertical distributions and periods, covering the entire larval development from intertidal areas to shelf and back to shore. The distribution of the early stages in surface layers promoted cross- and alongshore transport. Differences in the initial advection determined the positions where the more advanced stages were found later in the development. The subsurface distribution of advanced stages facilitated the transport to the inner shelf, limiting the cross-shore upwelling transport and promoting higher return to the adult habitats. Different periods of larval release resulted in contrasting dispersal patterns that could influence larval survival and recruitment to adult populations.

中文翻译：

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“来来回回” - 十足目巨蜥如何找到回家的路：Pachygrapsus marmoratus 的建模练习

摘要 Pachygrapsus marmoratus 是一种常见的沿海螃蟹，生活在大西洋东北部的岩石海岸。考虑到幼虫在潮间带区域释放，然后出口到发生幼虫发育的陆架水域，该物种呈现出一个浮游幼虫阶段，构成了一个有趣的扩散研究主题。陆上迁移到成虫栖息地被认为是由巨蜥阶段进行的。在夏季浮游动物调查期间获得的观察结果显示，在整个幼虫发育过程中，长尾鲽幼虫逐渐远离海岸，在表层发现早期幼虫阶段，而巨蜥则发生在更靠近海岸的地方。通过物理生态模型测试幼虫扩散和返回定居栖息地的垂直迁移机制，其中垂直分布随着幼虫发育而变化。生态数据，例如每个幼虫阶段的个体发育垂直分布、幼虫持续时间以及产卵时间和地点，都被整合到海洋模型中。模拟测试了不同的垂直分布和时期，涵盖了从潮间带区域到陆架再到海岸的整个幼虫发育。表层早期阶段的分布促进了跨岸和沿海运输。初始平流的差异决定了在发展后期发现更高级阶段的位置。高级阶段的地下分布促进了运输到内架，限制跨岸上升流运输并促进对成年栖息地的更高回报。不同时期的幼虫释放导致不同的散布模式，可能会影响幼虫的存活和向成年种群的招募。