Collaborative Research: Using Multiple Stable Isotopes to Investigate Middle to Late Holocene Ecological Responses by Adelie Penguins in the Ross Sea

阿德利企鹅(Pygocelis Adeliae)是南极洲数量最多的企鹅，尽管其种群目前面临着气候变化、海冰栖息地丧失和食物供应的威胁。在罗斯海地区，寒冷干燥的环境使阿德利企鹅的骨骼、羽毛、蛋壳甚至木乃伊遗骸得以保存在活跃的和被遗弃的群体中，这些群体可以追溯到最后一次冰盛期(45000多年前)之前到现在。4,000-2,000年前的一段升温时期，被称为企鹅的“最佳”时期，减少了海冰面积，使企鹅得以进入并在罗斯海南部繁殖。随着海洋状况随着当前变暖趋势的变化，这条海岸线可能会在未来重新被占领。该项目将使用保存完好的骨骼和其他组织来研究阿德利企鹅在饮食和觅食行为中的生态反应，这些骨骼和组织可以追溯到企鹅的最佳状态之前、期间和之后。首席调查人员将收集和分析罗斯海殖民地的骨骼、羽毛和蛋壳，以确定数千年来种群数量和觅食地点的变化。这些殖民地中的大多数与被海冰包围的开阔水域的高生产力区域有关。目前的变暖趋势正在导致该物种相对快速的生态反应，罗斯海中一些最大的殖民地可能会在未来50年内因海平面上升而被抛弃。最近建立的罗斯海海洋保护区旨在保护阿德利企鹅及其在该地区的觅食地免受人类影响，了解该物种过去如何应对气候变化将支持这一目标。该项目有利于美国国家科学基金会扩大南极系统、生物群和过程的基础知识。与他们的研究计划相结合，首席调查员将为研究驱动的课程创造本科生机会，将设计K-12课程并评估这些活动的有效性。两名研究生将得到该项目的支持，与K-12教师一起更新和完善课程。还包括一名博士、两名硕士和八名本科生的培训和部分支持。公众将通过社交媒体和YouTube频道的作品接触到公众。一套由三种稳定同位素(碳、氮和硫)组成的分析将在阿德利企鹅的骨骼和羽毛中进行分析，这些企鹅来自活跃的和被遗弃的企鹅群体，以评估生态随时间的变化。碳和氮的稳定同位素分析(δ13C和δ15N)通常用于研究动物的迁徙、觅食地点和饮食，特别是在可以远距离旅行的海洋物种中。硫磺(δ34S)并不常用，但越来越多地被用于提炼和证实碳和氮分析获得的数据。胶原蛋白是进行这些分析的最佳组织之一，因为它在骨骼中含量丰富，保存良好，而且很容易提取进行分析。利用这三种胶原蛋白的同位素，将对罗斯海南部、中部和北部的古代和现代企鹅群体进行调查，以确定数千年来企鹅种群和觅食地点的变化。这些殖民地中的大多数与罗斯海的三个多尼雅中的一个有关。这项研究将是第一次应用多个稳定同位素分析来调查数千年来活着的海鸟物种，该地区至今仍有海鸟存在。该项目的结果还将向管理层通报受气候变化影响的阿德利企鹅保护的最佳实践。该奖项反映了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。

The Adélie penguin (Pygoscelis adeliae) is the most abundant penguin in Antarctica, though its populations are currently facing threats from climate change, loss of sea ice habitat and food supplies. In the Ross Sea region, the cold, dry environment has allowed preservation of Adélie penguin bones, feathers, eggshell and even mummified remains, at active and abandoned colonies that date from before the Last Glacial Maximum (more than 45,000 years ago) to the present. A warming period at 4,000-2,000 years ago, known as the penguin ‘optimum’, reduced sea ice extent and allowed this species to access and reproduce in the southern Ross Sea. This coastline likely will be reoccupied in the future as marine conditions change with current warming trends. This project will investigate ecological responses in diet and foraging behavior of the Adélie penguin using well-preserved bones and other tissues that date from before, during and after the penguin ‘optimum’. The Principal investigators will collect and analyze bones, feathers and eggshells from colonies in the Ross Sea to determine changes in population size and feeding locations over millennia. Most of these colonies are associated with highly productive areas of open water surrounded by sea ice. Current warming trends are causing relatively rapid ecological responses by this species and some of the largest colonies in the Ross Sea are likely to be abandoned in the next 50 years from rising sea level. The recently established Ross Sea Marine Protected Area aims to protect Adélie penguins and their foraging grounds in this region from human impacts and knowledge on how this species has responded to climate change in the past will support this goal. This project benefits NSF’s mission to expand fundamental knowledge of Antarctic systems, biota, and processes. In association with their research program, the Principal Investigators will create undergraduate opportunities for research-driven coursework, will design K-12 curriculum and assess the effectiveness of these activities. Two graduate students will be supported by this project to update and refine the curricula working with K-12 teachers. There is also training and partial support included for one doctorate, two master and eight undergraduate students. General public will be reached through social media and YouTube channel productions.A suite of three stable isotopes (carbon, nitrogen, and sulfur) will be analyzed in Adelie penguin bones and feathers from active and abandoned colonies to assess ecological shifts through time. Stable isotope analyses of carbon and nitrogen (δ13C and δ15N) are commonly used to investigate animal migration, foraging locations and diet, especially in marine species that can travel over great distances. Sulfur (δ34S) is not as commonly used but is increasingly being applied to refine and corroborate data obtained from carbon and nitrogen analyses. Collagen is one of the best tissues for these analyses as it is abundant in bone, preserves well, and can be easily extracted for analysis. Using these three isotopes from collagen, ancient and modern penguin colonies will be investigated in the southern, central and northern Ross Sea to determine changes in populations and foraging locations over millennia. Most of these colonies are associated with one of three polynyas in the Ross Sea. This study will be the first of its kind to apply multiple stable isotope analyses to investigate a living species of seabird over millennia in a region where it still exists today. Results from this project will also inform management on best practices for Adelie penguin conservation affected by climate change.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.