An Xiaoyu, Zhang Ting, Niu Xin, Li Yupei, Yu Yangfei, Jiang Yongkang, Wang Jichao, Shi Haitao, Ding Li, Lin Liu
Ministry of Education Key Laboratory for Ecology of Tropical Islands, Key Laboratory of Tropical Animal and Plant Ecology of Hainan Province, College of Life Sciences, Hainan Normal University, Haikou, China.
Hainan Sansha Provincial Observation and Research Station of Sea Turtle Ecology, Sansha, China.
Appl Environ Microbiol. 2025 Aug 20;91(8):e0052725. doi: 10.1128/aem.00527-25. Epub 2025 Jul 23.
Sea turtles are renowned "living fossils" and ideal flagship marine conservation species. Sea turtles display high fidelity to their nesting grounds, and the quality of nesting grounds is related to the survival of sea turtles, in which microbial diversity, abundance, and potential pathogens are important indicators for assessing the quality of nesting grounds. The Xisha Islands are the largest nesting grounds for green turtles () in China. Protecting the security and sustainability of the nesting grounds is of significant importance. This study compared and analyzed the bacterial community composition and characteristics of the nests of green turtles using high-throughput Illumina sequencing technology. The results showed that the sand of nests before hatching showed higher bacterial diversity and richness than that after hatching ( < 0.001). Additionally, the bacterial diversity and richness of the hatched eggshells were significantly higher than those of unhatched egg contents and the gastrointestinal tracts of deceased hatchlings ( < 0.001). The relative abundance of , in the sand of nests after hatching was significantly decreased compared to that in the sand of nests before hatching ( < 0.05); however, the relative abundance of , , increased significantly ( < 0.001). Most of the bacteria identified in our study are opportunistic pathogens that cause infections in plants and animals. The unhatched egg contents had a larger amount of opportunistic pathogens than hatched eggshells and the gastrointestinal tracts of deceased hatchlings. The presence and long-term accumulation of these pathogens may disrupt the ecological balance of the microbial community in nesting grounds, increase the susceptibility of sea turtle eggs, and pose a threat to the hatching and hatchling survival of sea turtle eggs, thereby posing a certain level of safety risk. The outcomes of this study could offer scientific support for the management and restoration of the nesting grounds in the Xisha Islands.IMPORTANCEMany studies have shown that microorganisms influence the reproduction and hatching of sea turtles. The quality of nesting grounds is critically important for the successful reproduction of sea turtles, determining success in egg laying and influencing factors that affect the health of sea turtle populations. The Xisha Islands are the largest nesting grounds for green turtles in China. Regular and preventive monitoring of the microbial community composition in the sand and nests of nesting sites can contribute to the management and conservation of the nests.
海龟是著名的“活化石”和理想的旗舰海洋保护物种。海龟对其筑巢地表现出高度的忠诚度，筑巢地的质量与海龟的生存相关，其中微生物多样性、丰度和潜在病原体是评估筑巢地质量的重要指标。西沙群岛是中国绿海龟最大的筑巢地。保护筑巢地的安全和可持续性至关重要。本研究利用高通量Illumina测序技术对绿海龟巢穴的细菌群落组成和特征进行了比较和分析。结果表明，孵化前巢穴的沙子比孵化后显示出更高的细菌多样性和丰富度（<0.001）。此外，孵化后的蛋壳细菌多样性和丰富度显著高于未孵化的卵内容物和死亡幼龟的胃肠道（<0.001）。孵化后巢穴沙子中 、 的相对丰度与孵化前巢穴沙子相比显著降低（<0.05）；然而， 、 、 的相对丰度显著增加（<0.001）。我们研究中鉴定出的大多数细菌是引起动植物感染的机会性病原体。未孵化的卵内容物中机会性病原体的数量比孵化后的蛋壳和死亡幼龟的胃肠道更多。这些病原体的存在和长期积累可能会破坏筑巢地微生物群落的生态平衡，增加海龟卵的易感性，并对海龟卵的孵化和幼龟生存构成威胁，从而带来一定程度的安全风险。本研究结果可为西沙群岛筑巢地的管理和恢复提供科学支持。重要性许多研究表明，微生物会影响海龟的繁殖和孵化。筑巢地的质量对于海龟的成功繁殖至关重要，决定了产卵的成功率，并影响着影响海龟种群健康的因素。西沙群岛是中国绿海龟最大的筑巢地。对筑巢地点的沙子和巢穴中的微生物群落组成进行定期和预防性监测有助于巢穴的管理和保护。
