Populations at the edge: range dynamics and conservation of the Great Crested Newt under global change.

边缘种群：全球变化下大凤头蝾螈的分布范围动态和保护。

• 批准号: 2888979
• 金额: --
• 依托单位: University of Aberdeen
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2023
• 资助国家: 英国
• 起止时间: 2023 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2888979
• 关键词: Populations; edge; range; dynamics; conservation

Under anthropogenic exploitation and rapid environmental changes, many species are challenged with novel conditions, some are shifting their ranges moving to new suitable areas, and many are now threatened or extinct.Populations at the edges of species' range are key and often the most vulnerable: they are small, fragmented and less connected; harbour low genetic diversity and occupy suboptimal habitat; often face multiple anthropogenic stressors such as habitat loss and deterioration. However, populations that are at the range leading margin (the edge towards the direction of climate change) are key for successful species' range shifting: they already occupy locations where suitability will improve and thus could potentially readily expand, and might possess unique and locally favourable genetic variants. Understanding how these populations will respond to environmental change, both ecologically and evolutionarily, whether they will be able to persist under multiple natural and anthropogenic stressors, and how better we can assist them in this process, is crucial for effective species' conservation under global change.Predictive process-based models, that integrate the fundamental processes shaping species' ecology and adaptive responses, such as genetic variation, demography and dispersal, together with assessing impacts of multiple environmental stressors, are a powerful tool to both better understanding species' range dynamics and making better predictions of likely species' responses to future environmental change. These models are being developed, and they are now ripe for testing and for applications of conservation relevance.Amphibians are declining globally and are a high priority for biodiversity conservation. They are particularly vulnerable to multiple stressors as they rely on wetlands, an ecosystem particularly challenged by climate change and habitat loss, and are threatened by invasive species, diseases and pollution. The great crested newt Triturus cristatus is a declining species in Europe. In Britain it is an important wetland flagship species and has shown the highest rate of decline in recent years amongst native amphibians. In Scotland, T. cristatus is uncommon, with a restricted and fragmented range and, importantly, Scotland represents the north-west range of the species' world range. Critically, the species has a disjoint distribution in Scotland with an 80 km gap between the most northerly site in Fife and the most southerly Highland site. Much suitable unoccupied habitat has been identified and more is predicted to become suitable with climate change, creating potential for these edge populations to expand their range. However, multiple threats such has increasing habitat fragmentation, due to urbanization, agricultural changes and industrial developments, increasing drought, reduced genetic diversity, and increasing risk of predation from non-native species such as the signal crayfish and American mink, make it extremely uncertain whether this expansion and persistence will be at all possible.T. cristatus is thus an excellent and important species for investigating ecological and adaptive responses to environmental changes of populations at the warming range margins, and for applying new integrated process-based methods to predict these responses and guide conservation interventions.The overall aim of this project is to understand and predict the persistence of T. cristatus in Scotland under ongoing climate change and multiple stressors, and its potential expansion from marginal populations, to inform conservation management, moving towards a pro-active, rather than reactive, management of declining amphibians under global change.

在人类开发和环境迅速变化的情况下，许多物种面临新的挑战，有些物种正在迁移到新的适宜地区，许多物种现在受到威胁或灭绝。经常面临多种人为压力，如栖息地丧失和退化。然而，处于范围领先边缘（朝向气候变化方向的边缘）的种群是物种成功转移范围的关键：它们已经占据了适宜性将得到改善的位置，因此可能很容易扩展，并且可能拥有独特的和当地有利的遗传变异。了解这些种群将如何在生态和进化上对环境变化做出反应，它们是否能够在多种自然和人为压力下持续生存，以及我们如何更好地帮助它们在这一过程中，对于在全球变化下有效保护物种至关重要。基于预测过程的模型，整合了塑造物种生态和适应性反应的基本过程，如遗传变异、人口统计学和扩散，以及评估多种环境压力的影响，是更好地了解物种分布动态和更好地预测物种对未来环境变化的可能反应的有力工具。这些模型正在开发中，现在已经成熟，可以测试和应用于保护相关性。两栖动物在全球范围内正在减少，是生物多样性保护的高度优先事项。他们特别容易受到多重压力，因为他们依赖湿地，而湿地生态系统特别受到气候变化和栖息地丧失的挑战，并受到入侵物种，疾病和污染的威胁。大冠蝾螈Triturus cristatus在欧洲是一个下降的物种。在英国，它是一种重要的湿地旗舰物种，近年来在本土两栖动物中下降速度最快。在苏格兰，T.鸡冠是罕见的，具有有限和分散的范围，重要的是，苏格兰代表了该物种的世界范围的西北范围。至关重要的是，该物种在苏格兰有一个不相交的分布，在法夫最北端的网站和最南端的高地网站之间有80公里的差距。已经确定了许多合适的未被占用的栖息地，预计随着气候变化，更多的栖息地将变得合适，为这些边缘种群扩大其范围创造了潜力。然而，由于城市化、农业变化和工业发展、干旱增加、遗传多样性减少以及信号小龙虾和美国貂等非本地物种捕食风险增加，栖息地破碎化加剧等多重威胁使得这种扩张和持久性是否完全可能变得非常不确定。因此，鸡冠花是研究暖区边缘种群对环境变化的生态和适应性反应，以及应用新的基于过程的综合方法预测这些反应和指导保护措施的一个优秀和重要的物种。cristatus在苏格兰持续的气候变化和多重压力下，其潜在的扩张，从边缘人口，通知保护管理，走向积极主动，而不是反应，在全球变化下的两栖动物下降的管理。