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，水母生物量在1990年后急剧增加，并在2000年达到峰值。在2007-2012年的凉爽期，生物量再次增加。总的来说，在这个系统中，中等到寒冷的条件往往有利于水母。在数量增加的时期，水母可能会对白令海的食物网产生重大影响，包括瓦利眼鳕鱼渔业，因为水母直接以鱼类的年轻生命阶段为食，并与鱼类竞争食物。该项目将估算白令海主要水母Chrysaora melanaster的年龄结构和年龄特异性丰度，并将其与成年水母丰度联系起来，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，并调查在未来的气候情景下，这种水母的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经验项目参与研究。通过访问首席研究员，向小学生介绍海洋科学。s实验室。将为该项目建立一个网站，其中包括一些新颖的图像。图像处理的开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时间变化的学科中，在评估与环境变化有关的物种种群动态时纳入特定年龄丰度和年龄结构的重要性已得到证实。本文将对黑藻的早期浮游和成虫阶段的丰度和精细空间分布进行研究，确定其年龄结构，并建立种群模型来确定招募成功率和招募时间。这项研究将研究凝胶状浮游动物种群对大规模环境变化的反应，也将有助于理解白令海中反复出现的水母种群增加。声纳成像技术（ARIS1800）可以有效地采集同类海蜇的成虫，先进的光学浮游动物可视化（ZOOVIS）系统可以有效地采集小型海蜇的样本。净抽样和新的老龄化技术的结合将提供关于队列内年龄结构的急需信息，并将促进对招募过程的理解，例如单队列与多队列。这将有助于预测水母的数量及其对白令海生态系统的捕食影响。

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.