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。 生物量在2007-2012年的冷期再次增加。 总的来说，在这个系统中，温和到寒冷的条件往往有利于水母。 在人口增加期间，水母可能对白令海食物网产生重大影响，包括大眼鳕渔业，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。 该项目将估计白令海主要水母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，以了解其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，并调查这种水母的增加可能成为白令海的一种经常性模式，考虑到未来的气候情景，该项目将通过支持培训研究生来促进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计划参与研究。 小学生将通过访问首席研究员介绍海洋科学？的实验室。 将为该项目开发一个网站，包括新的图像。 图象处理的公开源码将张贴在万维网上，作为广大科学界的一个资源，在评估一个物种相对于环境变化的种群动态时，必须考虑到特定年龄的丰度和年龄结构，这在渔业科学和试图了解种群随时间变化的其他学科中是公认的。 将进行严格的调查，以估计C的丰度和细尺度空间分布。包括它们的早期发育和成年阶段，以确定它们的年龄结构，并构建一个种群模型来确定招募成功和招募时间。 这项研究将研究凝胶状浮游动物种群如何应对大规模的环境变化，也将有助于理解在白令海重新出现的水母种群增加。声纳成像技术（ARIS 1800）可有效地对同类物C的成年形式进行采样。quinqueclampha和先进的光学浮游动物可视化系统（ZOOVIS）可以有效地采样小型水母。净抽样和新的年龄技术相结合，将提供急需的关于队列内年龄结构的信息，并将有助于了解招募过程，例如单个队列与多个队列。这反过来又将有助于预测水母的丰度及其对白令海生态系统的掠夺性影响。

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.