Department of Biology and Biotechnologies ''Charles Darwin'', Sapienza University of Rome, Viale Dell'Università 32, 00185, Rome, Italy.
Marine Turtle Research Group, Department of Marine Animal Conservation and Public Engagement, Stazione Zoologica Anton Dohrn, Napoli, Italy.
Sci Rep. 2023 Dec 7;13(1):19906. doi: 10.1038/s41598-023-46958-4.
Climate change is reshaping global ecosystems at an unprecedented rate, with major impacts on biodiversity. Therefore, understanding how organisms can withstand change is key to identify priority conservation objectives. Marine ectotherms are being extremely impacted because their biology and phenology are directly related to temperature. Among these species, sea turtles are particularly problematic because they roam over both marine and terrestrial habitats throughout their life cycles. Focusing on green turtles (Chelonia mydas) in the Mediterranean Sea, we investigated the future potential changes of nesting grounds through time, assuming that marine turtles would shift their nesting locations. We modeled the current distribution of nesting grounds including both terrestrial and marine variables, and we projected the potential nesting distribution across the Mediterranean basin under alternative future greenhouse gas emission scenario (2000-2100). Our models show an increase in nesting probability in the western Mediterranean Sea, irrespective of the climate scenario we consider. Contrary to what is found in most global change studies, the worse the climate change scenario, the more suitable areas for green turtles will potentially increase. The most important predictors were anthropogenic variables, which negatively affect nesting probability, and sea surface temperature, positively linked to nesting probability, up to a maximum of 24-25 °C. The importance of the western Mediterranean beaches as potential nesting areas for sea turtles in the near future clearly call for a proactive conservation and management effort, focusing on monitoring actions (to document the potential range expansion) and threat detection.
气候变化正在以前所未有的速度重塑全球生态系统，对生物多样性产生重大影响。因此，了解生物体如何承受变化是确定优先保护目标的关键。海洋外温动物受到的影响极其严重，因为它们的生物学和物候学与温度直接相关。在这些物种中，海龟特别成问题，因为它们在整个生命周期中都会在海洋和陆地栖息地之间漫游。我们以地中海的绿海龟（Chelonia mydas）为例，通过假设海龟会改变它们的筑巢地点，来研究未来筑巢地随时间的潜在变化。我们对包括陆地和海洋变量在内的当前筑巢地分布进行建模，并在替代未来温室气体排放情景（2000-2100 年）下预测地中海盆地的潜在筑巢分布。我们的模型显示，无论我们考虑哪种气候情景，地中海西部的筑巢概率都会增加。与大多数全球变化研究的结果相反，气候变化情景越差，绿海龟潜在的适宜区域就会越多。最重要的预测因子是人为变量，它们会降低筑巢概率，而海面温度则与筑巢概率呈正相关，最高可达 24-25°C。未来不久，西地中海海滩作为海龟潜在筑巢区的重要性显然需要积极的保护和管理努力，重点是监测行动（记录潜在的范围扩展）和威胁检测。
