OCE-RIG: Novel approaches to better understanding the trophic role of small pelagic fishes and their critical link between the plankton and higher trophic levels

概述：小型的、成群结队的远洋鱼类通常是浮游生物生产达到海洋食物网上层营养水平的关键环节。尽管它们在生态和经济上具有重要意义，但我们对这些鱼类作为浮游动物的消费者所扮演的角色的理解存在明显的差距。为了更好地了解美国东北大陆架大型海洋生态系统中六种小型远洋鱼类的摄食动态，本研究采用了多方面的方法，采用了四种类型的分析。分析技术包括对肠道内容物的详细目视检查，散装和化合物特异性（氨基酸）稳定同位素分析，以及用于识别其他无法识别的猎物的DNA条形码技术。知识价值：由于它们在经济上的重要性，小型远洋鱼类受到了渔业机构（如NOAA）的极大兴趣和研究关注。然而，这项工作主要集中在监测种群规模或检查小型远洋鱼类作为其他重要自然资源猎物的性质。但是，小型远洋鱼类本身作为消费者，在决定浮游生物生产何时、何地以及有多少流向鱼类和营养上层，或可用于其他工序，包括因下沉而出口方面发挥着重要作用。在这个项目中，研究者将使用新的方法来研究小型远洋鱼类，而不是作为渔业资源，而是浮游食物网中的主要消费者。通过使用将应用于每个标本的技术收集与营养有关的数据，小型远洋鱼类对所有或特定浮游动物分类群自上而下影响的更大图景应该会出现。使用特定化合物的稳定同位素分析是特别值得注意的，因为这种强大的技术将能够检查食物网底部的变异性，从而深入了解影响这些重要物种的自下而上的力量。更广泛的影响：这个项目很大程度上是为了让来自代表性不足群体的许多年轻和未来的科学家参与研究活动。至少有八名本科生将参加研究巡航，以协助抽样工作。两名本科生暑期研究员将协助实验室数据收集工作，并将在伍兹霍尔度过一个夏天，以获得研究经验，并了解海洋学职业可能需要什么。一个早期的实验室助理将通过在实验室中领导样品处理活动获得宝贵的研究经验。参加全国会议的旅费支持将允许暑期学生或实验室助理与科学界分享这项研究的结果。为了培养当地学校的科学好奇心，调查员将接待来自东波士顿高中的学生，让他们在伍兹霍尔花一天时间参观各种实验室、设施，并参加调查员和其他科学家关于海洋学职业的演讲。学生的老师也将参加其中一次研究巡航，使她能够与许多其他学生分享她的经验。

Overview: Small, schooling pelagic fishes often represents a critical link in how planktonic production reaches the upper trophic levels of ocean food webs. Despite their ecological and economic importance, distinct gaps exist in our understanding of the role these fishes play as consumers of zooplankton. This study takes a multifaceted approach, employing four types of analyses in order to better understand the feeding dynamics of six species of small pelagic fishes in the Large Marine Ecosystem of the Northeast U.S. continental shelf. Analytical techniques include detailed visual inspection of gut contents, bulk and compound-specific (amino acid) stable isotope analyses, and DNA barcoding techniques for identifying the otherwise unidentifiable prey. Intellectual Merit: Because of their economic importance, small pelagic fishes have received substantial interest and research attention from fisheries agencies such as NOAA. This work, however, has largely focused on either monitoring population sizes or examining the nature of small pelagic fishes as prey for other important natural resources. But, being consumers themselves, small pelagic fishes play a major role in determining when, where, and how much planktonic production flows either towards fish and upper trophic levels or is available for other processes, including export due to sinking. In this project, the investigator will use novel approaches to study small pelagic fishes not as a fishery resource, but as major consumers within planktonic food webs. By gathering trophic-related data using techniques that will be applied to each specimen, a larger picture of the top-down impact that small pelagic fishes have on all or particular zooplankton taxa should emerge. The use of compound-specific stable isotope analyses is of particular note, as this powerful technique will afford the ability to examine variability at the base of the food web, thereby providing insight into the bottom-up forces that influence these important species. Broader Impacts: This project is heavily geared toward involving many young and future scientists from underrepresented groups in research activities. At least eight undergraduates will participate on research cruises, to assist with sampling efforts. Two undergraduate summer student fellows will assist in laboratory-based data collection efforts, and will spend the summer in Woods Hole gaining research experience and a sense of what a career in oceanography might entail. An early-career lab assistant will gain valuable research experience by leading the sample processing activities in the laboratory. Travel support to a national meeting will allow one of the summer students or lab assistant to share results from this study with the scientific community. In an effort to foster scientific curiosity in local schools, the investigator will host students from East Boston High School as they spend a day in Woods Hole visiting various labs, facilities and attend presentations by the investigator and other scientists on careers in oceanography. The students' teacher will also participate on one of the research cruises, enabling her to share her experience with many other students.