Collaborative Research: Demographic structure and recruitment patterns of the scyphozoan, Chrysaora melanaster, in the Bering Sea: the influence of climate on ecosystem function

在白令海东部，水母的生物量在1990年后急剧增加，并在2000年达到顶峰。在2007-2012年的凉爽时期，生物量再次增加。总体而言，在这个系统中，中等到寒冷的条件往往有利于水母。在种群增加期间，水母可能对白令海食物网产生重大影响，包括Walleye Pollock渔业，因为水母直接以幼鱼为食，并与鱼类争夺食物。该项目将估计白令海主要水母的年龄结构和特定年龄的丰度，并将其与成体水母的丰度联系起来，以了解它们的种群结构如何随时间变化。最终目标是估计这种水母的繁殖能力和成功与气候变化的关系，并调查这种水母在未来气候情况下增加成为白令海反复出现的模式的可能性。该项目将通过支持研究生的培训来促进STEM劳动力的发展。调查人员将参加K-12教师培训讲习班。本科生将通过现有的本科生研究体验项目参与研究。通过参观首席调查员S实验室，向小学生介绍海洋科学。将为该项目开发一个网站，包括新颖的图像。图像处理的开放源代码将作为更大的科学界的资源发布在万维网上。在渔业科学和其他试图了解种群的时间变化的学科中，将特定年龄的丰度和年龄结构纳入与环境变化有关的物种种群动态的评估中的重要性是众所周知的。我们将进行严密的调查，以估计黑腹隐翅虫的丰度和精细的空间分布，包括它们的早期浮游和成虫阶段，确定它们的年龄结构，并建立一个种群模型来确定招募成功和招募时机。这项研究将研究胶状浮游动物种群如何对大规模环境变化做出反应，并将有助于理解白令海不断出现的水母种群增长。声纳成像技术(ARIS1800)可以有效地对同类的西洋参成体进行采样，先进的浮游动物光学可视化系统(ZOOVIS)可以有效地对小型水母进行采样。净抽样和新的老龄化技术相结合，将提供关于队列内年龄结构的迫切需要的信息，并将有助于了解征聘过程，例如，单一队列与多队列。这反过来将使预测水母丰度及其对白令海生态系统的捕食影响成为可能。

In the eastern Bering Sea, jellyfish biomass increased dramatically after 1990 and peaked in 2000. Biomass increased again during the cool period of 2007-2012. Overall, moderate to cold conditions tend to favor jellyfish in this system. During times of population increase, jellyfish likely have major impacts on the Bering Sea food web, including Walleye Pollock fisheries, because the medusae directly feed on young life stages of fish and compete with fish for food. This project will estimate the age structure and age-specific abundances of the predominant jellyfish in the Bering Sea, Chrysaora melanaster, and will relate this to adult medusa abundance in order to understand how their population structure changes with time. The ultimate goal is to estimate the reproductive capacity and success of this jellyfish in relation to climate variability and to investigate the potential for increases of this jellyfish to become a recurring pattern in the Bering Sea given future climate scenarios.This project will contribute to STEM workforce development through the support for the training of a graduate student. The investigators will participate in K-12 teacher training workshops. Undergraduate students will be entrained into the research through an existing Research Experience for Undergraduates program. Elementary school students will be introduced to marine science through visits to the principal investigator?s laboratory. A website for the project, including novel imagery, will be developed. Open-source code for image processing will be posted on the World Wide Web as a resource for the larger scientific community.The importance of incorporating age-specific abundances and age structure in assessments of the population dynamics of a species in relation to environmental change is well-established in fisheries science and other disciplines that attempt to understand the temporal variation of populations. Rigorous investigations will be conducted to estimate the abundance and fine-scale spatial distribution of C. melanaster including both their early planktonic and adult stages, to determine their age structure, and to construct a population model to identify recruit success and recruitment timing. This research will examine how gelatinous zooplankton populations respond to large scale environmental changes and will also facilitate understanding of the reoccurring jellyfish population increases in the Bering Sea. The sonar imaging technologies (ARIS1800) are effective in sampling adult forms of the congener C. quinquecirrha and an advanced optical ZOOplankton VISualization (ZOOVIS) system can sample small jellyfish effectively. The combination of net sampling and new aging techniques will provide much needed information on the age-structure within cohorts and will facilitate understanding of recruitment processes, e.g. single cohort versus multiple cohorts. This will in turn enable forecasting of jellyfish abundance and their predatory impacts in the Bering Sea ecosystem.