Population ecology of arctic birds and mammals in a changing climate

气候变化下北极鸟类和哺乳动物的种群生态

• 批准号: RGPIN-2016-05898
• 负责人: Gauthier, Gilles
• 金额: $ 4.01万
• 依托单位: Université Laval
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=690608
• 关键词: Population; ecology; arctic; birds; mammals

The role of trophic interactions in controlling animal populations remains controversial, especially in Arctic ecosystems. Yet, the rapid pace of climate warming in Polar regions has a strong potential to disrupt species interactions and affect their population dynamic, especially for cyclic populations or those exploited by humans such as hunted species. The aim of my research program is to improve our fundamental understanding of the population dynamic of arctic birds and mammals and to determine how factors controlling populations, especially trophic interactions, will change with climate warming. Over the next 5 years I will study (1) the role of predation in generating population cycles in the Arctic, (2) seasonality as a potential driving force of population cycles, (3) the interaction between snow and animal demography and (4) how environmental change can affect the balance between hunting and natural mortality in exploited species. First, I will test experimentally the hypothesis that predation can generate lemming population cycles through a combination of direct (mortality from predation) and indirect effects (maternal effects on reproduction mediated by stress hormones). This will be achieved by measuring lemming demography and physiology using a large-scale manipulation (predator exclusion over a large fenced plot). Second, I will examine whether the peculiar seasonality of lemming demography (high fecundity and low mortality in winter) may be a driver of population cycles by measuring the length of the winter breeding season and modelling the effect of winter breeding on population growth. Third, a collapse of lemming cycles has been reported in areas where the winter has warmed, possibly due to changing snow condition. I will study the links between meteorological conditions, snow physical properties and winter reproduction in order to develop a model that could predict annual lemming abundance based on conditions of the snow pack. Fourth, I will assess how the interaction between human exploitation and changing environmental conditions can affect the population dynamic of migratory birds. I will examine how trophic mismatch can switch the balance between cause-specific mortalities (hunting vs natural causes) in young snow geese using a long-term capture-mark-recapture study. A mismatch occurs when plant phenology respond more quickly to climate warming than herbivores, which negatively affects herbivore reproduction. This research program will provide training for 7 graduate and 10 undergraduate students. It will contribute to a paradigm shift where predation is emerging as a dominant force controlling animal populations in a wide range of ecosystems. By combining empirical and modelling studies, I will also provide tools to generate quantitative predictions on future changes in wildlife populations in response to a rapidly changing environment.

营养相互作用在控制动物种群方面的作用仍然存在争议，特别是在北极生态系统中。然而，极地地区气候变暖的快速步伐有很大的潜力破坏物种之间的相互作用，影响它们的种群动态，特别是对于周期性种群或被人类利用的种群，如被猎杀的物种。我的研究计划的目的是提高我们对北极鸟类和哺乳动物种群动态的基本理解，并确定控制种群的因素，特别是营养相互作用，将如何随着气候变暖而变化。在接下来的5年里，我将研究（1）捕食在北极产生人口周期中的作用，（2）季节性作为人口周期的潜在驱动力，（3）雪和动物人口之间的相互作用，以及（4）环境变化如何影响狩猎和自然死亡率之间的平衡。首先，我将测试实验的假设，捕食可以产生旅鼠人口周期通过直接（捕食死亡率）和间接影响（母亲对生殖的影响介导的应激激素）的组合。这将通过测量旅鼠的人口统计学和生理学，使用大规模的操纵（捕食者排除在一个大的围栏阴谋）。其次，我将研究是否特有的季节性旅鼠人口（高繁殖力和低死亡率在冬季）可能是一个驱动程序的人口周期，通过测量冬季繁殖季节的长度和模拟冬季繁殖对人口增长的影响。第三，据报道，在冬季变暖的地区，旅鼠的周期会崩溃，这可能是由于雪况的变化。我将研究气象条件，雪的物理特性和冬季繁殖之间的联系，以开发一个模型，可以预测每年旅鼠丰富的基础上积雪的条件。第四，我将评估人类开发和不断变化的环境条件之间的相互作用如何影响候鸟的种群动态。我将研究如何营养不匹配可以切换之间的平衡的原因特异性死亡率（狩猎与自然原因）在年轻雪雁使用长期捕获标记再捕获研究。当植物物候对气候变暖的反应比食草动物更快时，就会发生不匹配，这会对食草动物的繁殖产生负面影响。该研究项目将为7名研究生和10名本科生提供培训。这将有助于一种范式转变，即捕食正在成为控制广泛生态系统中动物种群的主导力量。通过结合实证和建模研究，我还将提供工具，以产生对野生动物种群未来变化的定量预测，以应对快速变化的环境。