Collaborative Research: ORCC: Trophic phenotypes as eco-evolutionary mediators of resilience to climate change

随着湖泊和其他生境因气候变暖而不断变化，重要的是确定哪些生态系统和生物最脆弱或能够持续存在。美国缅因州的13个北极木炭种群是这种冷适应物种最南端的种群，预计将面临气候变暖和物种入侵的挑战。我们推测，这些种群改变饮食和摄食特征的能力可能对它们未来的持久性特别重要。这项研究调查了四个含有木炭的湖泊，以确定它们的栖息地和食物网有何不同，以及这与特定的北极木炭行为和摄食特征有何关系。发出声音的电子标签将被用来以精细的尺度跟踪单个碳粉的运动。20年的遗传样本将有助于确定字符特征可能会从适应或其他过程中发生变化。定量模型将被用来预测饮食和栖息地的差异如何影响增长和种群生产力，以及随后北极木炭种群对持续变暖和生境变化的适应能力。研究缅因州的北极木炭不仅有助于保护和管理该物种，还将评估与其范围南部边缘的其他物种相关的理论。项目科学家将与保护组织和管理机构密切合作，确保所获得的知识迅速有效地传播，以造福于人。许多鱼类和其他类群的后缘种群生活在孤立的小型避难所栖息地，因此被认为容易受到非生物和生物因素相互作用的影响，这些因素可能会将它们的生态位压缩到崩溃的边缘。该项目测试了一个有机-生态进化框架，用于评估营养特征多样性和变化在应对气候变化方面的作用，将营养特征变化的遗传和可塑性部分与人口统计学、生境和社区环境联系起来，并最终将生态进化潜力持续。美国缅因州的内陆北极木炭是该物种在北美最南端的种群。此外，缅因州北极木炭种群中有证据表明，种群在营养上存在差异，营养特征变异可以随着资源的变化而改变。该项目将把有关北极碳素基因类型、表型(形态)、饮食和运动(声学遥测)的信息与湖沼学和食物网结构信息结合起来，以在基因、表型和群落的变化之间产生潜在的机械联系。遗传推断的家系和全基因组测序方法将与表型数据和对CHAR的长期(20年)标记重新捕获分析相结合，以估计影响当代性状不稳定和种群动态的遗传和基因组参数。基于个体的模型将模拟在不同温度、鱼类群落组成和湖泊生态系统类型下，碳在营养特征中的生物能量学和持久性。总体而言，这项研究将通过气候变化、种内和种间相互作用以及表型之间复杂的生态反馈的视角，提高预测边缘种群命运的能力。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

As lakes and other habitats continue to change in response to a warming climate, it is important to identify which ecosystems and organisms will be most vulnerable or able to persist. The thirteen populations of Arctic charr in Maine, USA, are the most southern remaining populations of this cold-adapted species and are expected to face challenges from climate warming and species invasions. We hypothesize that the ability of such populations to shift their diets and feeding traits may be especially important to their future persistence. This study investigates four of these charr-bearing lakes to determine how their habitat and food webs differ, and how this relates to specific Arctic charr behaviors and feeding traits. Electronic tags that emit sound will be used to track the movements of individual charr at fine scales. Twenty years of genetic samples will help determine how charr traits might change from adaptation or other processes. Quantitative models will be used to predict how differences in diet and habitat affect growth and population productivity, and subsequently the resilience of Arctic charr populations to continued warming and changes in habitats. Studying Arctic charr in Maine will help the conservation and management of not only this species, but also assess theory relevant to other species at the southern edge of their ranges. The project scientists will work closely with conservation groups and management agencies to ensure knowledge gained is quickly and effectively communicated for benefit. Many trailing-edge populations of fishes and other taxa inhabit small refuge habitats that are isolated and thus presumed vulnerable to interacting abiotic and biotic factors that could compress their niche to the point of collapse. This project tests an organismal-eco-evolutionary framework for assessing the role of trophic trait diversity and change in resilience to climate change, linking the genetic and plastic components of trophic trait variation to population demography, habitat and community contexts, and ultimately eco-evolutionary potential for persistence. Landlocked Arctic charr in Maine, USA, are the most southern populations of this species in North America. Moreover, there is evidence among Maine Arctic charr populations that populations are trophically divergent and that trophic trait variation can change in response to changes in resources. This project will integrate information on Arctic charr genotypes, phenotypes (morphology), diet, and movements (acoustic telemetry) with limnology and food web structure information to generate potential mechanistic links among variation in genotype, phenotype, and communities. Genetically inferred pedigrees and whole genome sequencing approaches will be integrated with phenotypic data and long-term (20 year) mark-recapture analysis of charr to estimate genetic and genomic parameters affecting trait lability and population dynamics in contemporary time. Individual-based models will simulate the bioenergetics and persistence of charr across trophic traits under a variety of temperatures, fish community compositions, and lake ecosystem types. Collectively, this research will improve the ability to predict the fate of trailing-edge populations through the lens of complex ecological feedbacks among climate change, intra- and interspecific interactions, and phenotypes.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.