Green and hawksbill sea turtle nesting in the Gulf of Guinea: A 9-year survey

Sea turtles are critical components of marine ecosystems, and their conservation is important for Ocean Governance and Global Planet Health. However, there is limited knowledge of their ecology in the Gulf of Guinea. To fill this knowledge gap, this study presents the first integrative assessment of green and hawksbill turtles in the region, combining nesting area surveys over 9 years, and telemetry data, to offer insights into these population dynamics, and behaviours including nesting preferences, morphological and reproductive parameters, diving patterns and inter-nesting core-use areas. Green turtles are likely making a recovery in São Tomé, potentially driven by sustained conservation efforts. In contrast, the status of the hawksbill turtle remains less clear. There are preliminary indications of recovery, but we interpret this cautiously. Coupled with satellite tracking, this study estimated that 482 to 736 green turtles, and 135 to 217 hawksbills, nest on the beaches of São Tomé. Their movements overlap significantly with a proposed Marine Protected Area (MPA), which suggests they may be well placed for conservation if managed appropriately. However, the presence of artisanal fisheries and emerging threats, such as sand mining and unregulated tourism, highlight the urgent need for robust management strategies that align global conservation objectives with local socioeconomic realities. This study significantly enhances our understanding of the ecology and conservation needs of the green and hawksbill turtles in the Gulf of Guinea. The insights gleaned here can contribute to the development of tailored conservation strategies that benefit these populations and the ecosystem services upon which they depend.海龟是海洋生态系统的关键组成部分，其保护工作对于海洋治理（Ocean Governance）与全球行星健康（Global Planet Health）均具有重要意义。然而，目前学界对几内亚湾（Gulf of Guinea）海域海龟的生态特征认知仍较为有限。为填补这一认知空白，本研究针对该区域的绿海龟（green turtle）和玳瑁（hawksbill turtle）开展了首次综合性评估，整合为期9年的筑巢区域调查数据与遥测（telemetry）数据，以深入解析该种群的动态变化与行为特征，涵盖筑巢偏好、形态学与繁殖参数、潜水模式以及筑巢间期核心活动区域。圣多美（São Tomé）海域的绿海龟种群大概率正处于恢复阶段，这一趋势或得益于持续推进的保护工作。与之形成鲜明对比的是，玳瑁种群的现状仍不甚明朗。目前虽有初步迹象显示其种群有所恢复，但研究团队对此持谨慎解读态度。结合卫星追踪数据，本研究估算得出，圣多美沿岸海滩的筑巢绿海龟数量约为482至736只，玳瑁则为135至217只。这些海龟的活动范围与一处拟建的海洋保护区（Marine Protected Area, MPA）高度重叠，这意味着若能开展合理管理，该区域将为海龟保护提供绝佳契机。然而，当地存在的手工渔业以及采砂、无管制旅游等新兴威胁，凸显了制定完善管理策略的迫切性——此类策略需兼顾全球保护目标与当地社会经济实际情况。本研究极大地深化了学界对几内亚湾海域绿海龟与玳瑁的生态特征及保护需求的认知。本研究获取的核心见解，可为制定针对性保护策略提供参考，从而惠及这些海龟种群及其赖以生存的生态系统服务。