ABSTRACT: Sea turtles exhibit complex life histories, encompassing intermittent use of multiple spatially separated habitats throughout long lifespans. This broad scope presents challenges for collecting comprehensive biological and ecological data, yet absence of such information complicates evaluation of management strategies for populations at risk of extinction. Hawksbill sea turtles Eretmochelys imbricata are endangered worldwide, primarily due to long-term, directed harvest. However, available information regarding life stage durations, somatic growth patterns, and maturation attributes to enhance understanding of anthropogenic impacts and recovery potential remains constrained. To address these data gaps in the western North Atlantic, we conducted skeletochronological analysis for hawksbills stranded along US coastlines to generate straight-line carapace length (SCL)-at-age and somatic growth data. Generalized additive mixed models and bootstrapped von Bertalanffy growth curves were used to characterize age at maturation and covariate influence on somatic growth. For a subset of turtles, annual bone growth increment-specific stable isotope and trace element analyses were incorporated to evaluate habitat use relative to age. Integration of these data sources indicated that juveniles transitioned from oceanic to neritic habitat at 1-3 yr old and mean SCLs of 23-24 cm (range 15.7-35.0 cm). Initial ages at maturation for this population at minimum nesting female SCLs were estimated at 15-25 yr. Somatic growth varied significantly relative to size, age, and stranding location, while no association with sex or calendar year was observed. Our results demonstrate the utility of these complementary analytical approaches for generating baseline data fundamental to characterizing hawksbill sea turtle population attributes.

中文翻译：

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玳瑁海龟的生命阶段持续时间、体细胞生长模式和成熟年龄

摘要：海龟表现出复杂的生活史，包括在整个漫长的生命周期中间歇性地使用多个空间分离的栖息地。这种广泛的范围给收集全面的生物和生态数据带来了挑战，但缺乏此类信息会使对濒临灭绝的种群的管理策略的评估变得复杂。玳瑁海龟Eretmochelys imbricata在世界范围内濒临灭绝，主要是由于长期定向采伐。然而，关于生命阶段持续时间、体细胞生长模式和成熟属性的可用信息仍然有限，以增强对人为影响和恢复潜力的理解。为了解决北大西洋西部的这些数据空白，我们对搁浅在美国海岸线的玳瑁进行了骨骼年代学分析，以生成直线甲壳长度 (SCL)-年龄和体细胞生长数据。广义加性混合模型和自举 von Bertalanffy 生长曲线用于表征成熟年龄和对体细胞生长的协变量影响。对于一部分海龟，结合年度骨骼生长增量特定的稳定同位素和微量元素分析来评估栖息地利用与年龄的关系。这些数据来源的整合表明，幼鱼在 1-3 岁时从海洋过渡到浅海栖息地，平均 SCL 为 23-24 厘米（范围 15.7-35.0 厘米）。该种群在最低筑巢雌性 SCL 时的初始成熟年龄估计为 15-25 岁。相对于大小、年龄和搁浅位置，体细胞生长有显着差异，而没有观察到与性别或日历年的关联。我们的结果证明了这些补充分析方法在生成基线数据方面的效用，这些基线数据是表征玳瑁种群属性的基础。相对于大小、年龄和搁浅位置，体细胞生长有显着差异，而没有观察到与性别或日历年的关联。我们的结果证明了这些补充分析方法在生成基线数据方面的效用，这些基线数据是表征玳瑁种群属性的基础。相对于大小、年龄和搁浅位置，体细胞生长有显着差异，而没有观察到与性别或日历年的关联。我们的结果证明了这些补充分析方法在生成基线数据方面的效用，这些基线数据是表征玳瑁种群属性的基础。