Collaborative Research: Investigating Holocene Shifts in the Diets and Paleohistory of Antarctic Krill Predators

合作研究：调查全新世南极磷虾捕食者饮食和古历史的变化

• 批准号: 1826712
• 负责人: Kelton McMahon
• 金额: $ 13.98万
• 依托单位: University of Rhode Island
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-11-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1826712&HistoricalAwards=false
• 关键词: Collaborative; Research; Investigating; Holocene; Shifts

The Antarctic marine ecosystem is highly productive and supports a diverse range of ecologically and commercially important species. A key species in this ecosystem is Antarctic krill, which in addition to being commercially harvested, is the principle prey of a wide range of marine organisms including penguins, seals and whales. The aim of this study is to use penguins and other krill predators as sensitive indicators of past changes in the Antarctic marine food web resulting from climate variability and the historic harvesting of seals and whales by humans. Specifically this study will recover and analyze modern (20 year old), historic (20-200 year old) and ancient (200-10,000 year old) penguin and other krill predator tissues to track their past diets and population movements relative to shifts in climate and the availability of Antarctic krill. Understanding how krill predators were affected by these factors in the past will allow us to better understand how these predators, the krill they depend on, and the Antarctic marine ecosystem as a whole will respond to current challenges such as global climate change and an expanding commercial fishery for Antarctic krill. The project will further the NSF goals of training new generations of scientists and of making scientific discoveries available to the general public. This project will support the cross-institutional training of undergraduate and graduate students in advanced analytical techniques in the fields of ecology and biogeochemistry. In addition, this project includes educational outreach aimed encouraging participation in science careers by engaging K-12 students in scientific issues related to Antarctica, penguins, marine ecology, biogeochemistry, and global climate change.This research will help place recent ecological changes in the Southern Ocean into a larger historical context by examining decadal and millennial-scale shifts in the diets and population movements of Antarctic krill predators (penguins, seals, and squid) in concert with climate variability and commercial harvesting. This will be achieved by coupling advanced stable and radio isotope techniques, particularly compound-specific stable isotope analysis, with unprecedented access to modern, historical, and well-preserved paleo-archives of Antarctic predator tissues dating throughout the Holocene. This approach will allow the project to empirically test if observed shifts in Antarctic predator bulk tissue stable isotope values over the past millennia were caused by climate-driven shifts at the base of the food web in addition to, or rather than, shifts in predator diets due to a competitive release following the historic harvesting of krill eating whale and seals. In addition, this project will track the large-scale abandonment and reoccupation of penguin colonies around Antarctica in response to changes in climate and sea ice conditions over the past several millennia. These integrated field studies and laboratory analyses will provide new insights into the underlying mechanisms that influenced past shifts in the diets and population movements of charismatic krill predators such as penguins. This will allow for improved projections of the ecosystem consequences of future climate change and anthropogenic harvesting scenarios in the Antarctica that are likely to affect the availability of Antarctic krill.

南极海洋生态系统生产力很高，支持多种具有生态和商业重要性的物种。 这个生态系统中的一个关键物种是南极磷虾，它除了进行商业捕捞外，还是包括企鹅、海豹和鲸鱼在内的多种海洋生物的主要猎物。 这项研究的目的是利用企鹅和其他磷虾捕食者作为过去由于气候变化以及人类对海豹和鲸鱼的捕捞而导致的南极海洋食物网变化的敏感指标。具体来说，这项研究将恢复并分析现代（20岁）、历史（20-200岁）和古代（200-10,000岁）企鹅和其他磷虾捕食者组织，以跟踪它们过去的饮食和相对于气候变化的种群运动以及南极磷虾的供应情况。了解磷虾捕食者过去如何受到这些因素的影响，将使我们能够更好地了解这些捕食者、它们所依赖的磷虾以及整个南极海洋生态系统将如何应对当前的挑战，例如全球气候变化和不断扩大的商业活动南极磷虾渔业。 该项目将进一步实现国家科学基金会培养新一代科学家和向公众提供科学发现的目标。该项目将支持本科生和研究生在生态学和生物地球化学领域的先进分析技术的跨机构培训。 此外，该项目还包括教育推广活动，旨在通过让 K-12 学生参与与南极洲、企鹅、海洋生态学、生物地球化学和全球气候变化相关的科学问题，鼓励参与科学职业。这项研究将有助于了解南部地区最近的生态变化通过研究南极磷虾捕食者（企鹅、海豹和鱿鱼）的饮食和人口流动的十年和千年规模的变化，与气候变化和商业相结合，将海洋纳入更大的历史背景收获。 这将通过结合先进的稳定和放射性同位素技术，特别是特定化合物的稳定同位素分析，以及前所未有地获得现代、历史和保存完好的南极捕食者组织古档案来实现，这些档案可追溯到整个全新世。 这种方法将使该项目能够凭经验测试过去几千年来观察到的南极捕食者大块组织稳定同位素值的变化是否是由气候驱动的食物网基础变化引起的，或者是由于捕食者饮食的变化造成的由于历史性捕捞吃磷虾的鲸鱼和海豹后的竞争性释放。此外，该项目还将追踪南极洲周围企鹅群落的大规模废弃和重新占领，以应对过去几千年来气候和海冰条件的变化。这些综合的实地研究和实验室分析将为影响企鹅等魅力磷虾捕食者过去的饮食和种群流动的潜在机制提供新的见解。这将有助于更好地预测未来气候变化和南极洲人为捕捞情景可能影响南极磷虾供应的生态系统后果。