Oceanic dispersal characterizes the early juvenile life‐stages of numerous marine species of conservation concern. This early stage may be a ‘critical period’ for many species, playing an overriding role in population dynamics. Often, relatively little information is available on their distribution during this period, limiting the effectiveness of efforts to understand environmental and anthropogenic impacts on these species. Here we present a simple model to predict annual variation in the distribution and abundance of oceanic‐stage juvenile sea turtles based on species’ reproductive output, movement and mortality. We simulated dispersal of 25 cohorts (1993–2017) of oceanic‐stage juveniles by tracking the movements of virtual hatchling sea turtles released in a hindcast ocean circulation model. We then used estimates of annual hatchling production from Kemp's ridley Lepidochelys kempii (n = 3), green Chelonia mydas (n = 8) and loggerhead Caretta caretta (n = 5) nesting areas in the northwestern Atlantic (inclusive of the Gulf of Mexico, Caribbean Sea and eastern seaboard of the U.S.) and their stage‐specific mortality rates to weight dispersal predictions. The model's predictions indicate spatial heterogeneity in turtle distribution across their marine range, identify locations of increasing turtle abundance (notably along the U.S. coast), and provide valuable context for temporal variation in the stranding of young sea turtles across the Gulf of Mexico. Further effort to collect demographic, distribution and behavioral data that refine, complement and extend the utility of this modeling approach for sea turtles and other dispersive marine taxa is warranted. Finally, generating these spatially‐explicit predictions of turtle abundance required extensive international collaboration among scientists; our findings indicate that continued conservation of these sea turtle populations and the management of the numerous anthropogenic activities that operate in the northwestern Atlantic Ocean will require similar international coordination.

中文翻译：

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北大西洋西部海龟“失去的岁月”的预测分布和丰度

海洋扩散是许多受保护的海洋物种的早期幼年生命阶段的特征。这个早期阶段可能是许多物种的“关键时期”，在种群动态中发挥着压倒一切的作用。通常，在此期间，关于其分布的信息相对较少，限制了了解环境和人为对这些物种的影响的努力的有效性。在这里，我们提出了一个简单的模型，可以根据物种的繁殖输出、运动和死亡率来预测海洋阶段幼年海龟的分布和丰度的年度变化。我们通过跟踪后报海洋环流模型中释放的虚拟孵化海龟的运动，模拟了 25 组（1993-2017 年）海洋阶段幼龟的扩散。然后，我们使用了来自 Kemp'sridley Lepidochelys kempii (n = 3)、green Chelonia mydas (n = 8) 和 loggerhead Caretta caretta (n = 5) 在大西洋西北部（包括墨西哥湾，加勒比海和美国东海岸）及其特定阶段死亡率对权重扩散预测。该模型的预测表明海龟分布在其海洋范围内的空间异质性，确定海龟丰度增加的位置（特别是沿美国海岸），并为墨西哥湾幼海龟搁浅的时间变化提供有价值的背景。进一步努力收集完善的人口统计、分布和行为数据，补充和扩展这种建模方法对海龟和其他分散海洋类群的效用是有必要的。最后，生成这些海龟丰度的空间明确预测需要科学家之间广泛的国际合作；我们的研究结果表明，对这些海龟种群的持续保护和对在大西洋西北部开展的众多人为活动的管理将需要类似的国际协调。