Interpopulation variation and temperature mediation of the impacts of biological invasions

生物入侵影响的种群间变异和温度调节

• 批准号: RGPIN-2022-03235
• 负责人: Ricciardi, Anthony
• 金额: $ 4.01万
• 依托单位: McGill University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=764497
• 关键词: Interpopulation; variation; temperature; mediation; impacts

Ecologists have made substantial progress in understanding how nonnative species invade ecosystems, but have been less successful at predicting when and where such species will have significant impacts. A major challenge for prediction is context dependence, in which a nonnative species can have considerably different effects in different ecosystems and at different times. The long-term goals of my work are to i) identify environmental factors that drive spatiotemporal variation in the impact of nonnative species, and ii) integrate these factors into general predictive models. Over the next five years, I will investigate the causes of spatiotemporal variation in rates of prey consumption by nonnative freshwater animals. My lab will conduct experiments to test three overarching hypotheses. The first hypothesis predicts that individuals at the front of a spreading population exert greater impacts on food webs because such individuals are selected to be more voracious and competitive than those from the high-density core of the population. Differences in animal behavior and body size at invasion fronts have been recognized for several years, and our lab has found evidence that predation is amplified at invasion fronts. We will build on our previous work by testing the effect of time-since-invasion on the functional response (feeding efficiency) of individuals within and between populations of aquatic invasive species. Second, in these experiments we will manipulate ambient temperature to test the hypothesis that warming enhances an invasive predator's functional response such that it increases the likelihood of prey population decline. Third, we will investigate latitudinal patterns by comparing functional responses of nonnative populations of fish and crustaceans distributed across the Great Lakes-St. Lawrence River basin. We hypothesize that individuals from higher-latitude populations have stronger functional responses (owing to more rapid growth rates) than those from lower-latitude populations. Overall, this research will inform theory and aid risk assessment by identifying environmental drivers of variation in an invader's impacts across space and time. In particular, it should reveal predictive information on how the impacts of nonnative species in aquatic ecosystems are affected by climate change.

生态学家在了解外来物种如何入侵生态系统方面取得了重大进展，但在预测这些物种何时何地将产生重大影响方面却不太成功。预测的一个主要挑战是环境依赖性，其中一个非本地物种可以在不同的生态系统和不同的时间有相当不同的影响。我的工作的长期目标是i）确定驱动非本地物种影响的时空变化的环境因素，ii）将这些因素整合到通用预测模型中。在接下来的五年里，我将研究非本地淡水动物捕食率时空变化的原因。我的实验室将进行实验来验证三个首要假设。第一个假设预测，在一个扩散的人口前端的个人施加更大的影响，食物网，因为这样的个人被选择更贪婪和竞争比那些从人口的高密度核心。动物行为和身体大小在入侵前沿的差异已经被认识了好几年，我们的实验室已经发现了捕食在入侵前沿被放大的证据。我们将建立在我们以前的工作，通过测试的影响，因为入侵的功能反应（摄食效率）的个人内和之间的水生入侵物种的种群。第二，在这些实验中，我们将操纵环境温度来测试的假设，即变暖增强了入侵捕食者的功能反应，使它增加了猎物种群下降的可能性。第三，我们将调查纬度模式，通过比较分布在大湖-圣劳伦斯河流域的鱼类和甲壳类动物的非本地种群的功能反应。我们假设来自高纬度人群的个体比来自低纬度人群的个体具有更强的功能反应（由于更快的生长速率）。总的来说，这项研究将通过确定入侵者在空间和时间上的影响变化的环境驱动因素，为理论和风险评估提供信息。特别是，它应该揭示预测信息，说明气候变化如何影响水生生态系统中的非本地物种的影响。