Sea turtles are globally threatened due to short- and long-term exposure to anthropogenic activities. Many life-history traits make it difficult to study these species in the wild. Stranding events provide invaluable data to infer key aspects of sea turtle ecology, such as regional occurrence, health status, mortality rates, and potential threats. In this study, we investigate spatial and temporal patterns of sea turtle occurrence and mortality in the southwestern Atlantic Ocean based on a systematic, large-scale survey programme covering 1040 km of coastline during 732 d of two consecutive years. From the 12 571 animals recovered, juvenile green turtles were the most common (90.4%), but four other species were also recorded. A significant non-linear effect of time and space in the number of stranding events was observed. The most parsimonious mixed linear model further indicated that stranding events were influenced by individual (sex, size), health (body condition, pathologies, decomposition), and oceanographic factors (chlorophyll-a, sea surface temperature, salinity, wave height). More than simply describing the spatiotemporal occurrence and aspects of sea turtles’ life history in an otherwise understudied area, this intensive field study provides evidence for relatively high mortality rates—an essential baseline information for guiding conservation efforts.

中文翻译：

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西南大西洋海龟搁浅的高发率

由于人类活动的短期和长期暴露，海龟在全球受到威胁。许多生活史特征使在野外研究这些物种变得困难。搁浅事件提供了宝贵的数据，可推断海龟生态学的关键方面，例如区域发生情况，健康状况，死亡率和潜在威胁。在这项研究中，我们基于连续两年732 d涵盖海岸线1040 km的系统，大规模调查程序，调查了西南大西洋海龟发生和死亡的时空格局。从恢复的12571只动物中，最常见的是绿海龟（90.4％），但也记录了其他4种。观察到时间和空间对搁浅事件数量的显着非线性影响。最简约的混合线性模型还表明，搁浅事件受个人（性别，大小），健康（身体状况，病理，分解）和海洋学因素（叶绿素a，海面温度，盐度，波高）的影响。这项深入的现场研究不仅简单地描述了在未被充分研究的区域中海龟的时空发生和生活史方面，还提供了相对较高死亡率的证据，这是指导保护工作的重要基础信息。