LTREB: Pace of life and differential migration in changing environments

几千年来，人类一直对许多动物为寻找食物、繁殖和生存而进行的长途迁徙着迷。近几十年来，科学家们观察到，越来越多的动物没有像它们的祖先那样迁徙得那么远。为什么有些人突然停止迁徙，而另一些人继续采用传统的长途迁徙？这些变化的行为对迁徙物种的后果是什么，这对人类社会有什么影响？通过对雏鹅进行的一项独特的长期研究，研究人员将通过研究气候变化和个体生殖史(迄今为止他们养育了多少婴儿)对迁徙距离的双重影响，以及迁徙决定对未来生存和繁殖机会的影响来解决这些问题。然后，研究小组将量化每种类型的迁徙行为对整体雏鹅数量的贡献。布兰特鹅是太平洋沿岸鳗草的主要食草者，它们通过影响沿海经济，该栖息地是无数鱼类和贝类物种的养殖地。如果没有丰富的淡水来维持健康的鳗草床，并且对影响淡水丰度的因素有坚实的了解，依赖鳗草河口的渔业可能会受到影响。在进行这项研究的同时，该团队将在STEM领域培训一批非常多样化的学生，包括阿拉斯加原住民学生。该团队还将为K-12学生开发涵盖野生动物采样技术和模型的开放教育材料。与其他分类群一样，随着气候变暖和更南边的栖息地被人类破坏，许多海燕停止季节性迁徙，在高纬度越冬。但许多人继续投资于传统的长途迁徙到南纬地区，随着时间的推移，在未出生的人口中创造了一种不同的迁徙策略模式。通过利用阿拉斯加对Brant的长期研究，研究人员将测试环境变化是否允许Brant个体从广泛的迁徙策略中进行平等选择，或者环境变化是否从方向上有利于与生活史节奏(快与慢生殖投资和寿命)相关的特定迁徙策略(长距离与短距离)，这是通过终生进化适应度来衡量的。建模还将揭示个体迁徙策略对幼崽种群生存能力的贡献，以及幼崽种群对它们放牧的生态系统的影响。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。

For millennia, humans have been fascinated by the long-distance migrations that many animals undergo to find food, reproduce, and survive. In recent decades, scientists have observed that more and more animals are not migrating as far as their ancestors did. Why is it that some individuals stop their migration short while others continue to adopt traditional, long-distance migrations? What are the consequences of these changing behaviors for migratory species, and how does this impact human societies? Using a unique long-term study of brant geese, the researchers will address these questions by studying the dual influence of climate change and an individual’s reproductive history (how many babies they have reared to date) on migration distance, and the impact of migratory decisions on future chances of survival and reproduction. The team will then quantify the contribution of each type of migration behavior to the overall abundance of brant geese. Brant geese affect coastal economies via their role as primary grazers of eelgrass along the Pacific Coast, the same habitat that serves as the rearing ground for a myriad of fish and shellfish species. Without an abundance of brant to maintain healthy beds of eelgrass, and a solid understanding of the factors affecting brant abundance, the fishing industries that rely on eelgrass estuaries could suffer. While carrying out the study, the team will train a highly diverse group of students, including Alaska Native students, in STEM fields. The team will also develop open educational materials covering wildlife sampling techniques and models for K-12 students.Like other taxa, many brant are stopping their seasonal migration short and wintering at high latitudes as the climate warms and as habitats further south are damaged by humans. But many individuals continue to invest in traditional long-distance migrations to southern latitudes, creating a divergent pattern of migration tactics within brant populations over time. By leveraging a long-term study of brant in Alaska, the researchers will test whether environmental change is allowing individual brant to choose equally from a broad range of migration strategies, or if environmental change is directionally favoring a particular migration strategy (long- vs. short-distance) associated with life-history tempo (fast vs. slow reproductive investment and lifespans), as measured via the currency of lifetime evolutionary fitness. Modeling will also reveal the contributions of individual migration tactics to brant population viability, and the impact of brant populations on the ecosystems they graze.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.