US-GLOBEC NEP Phase IIIa: Efffects of Climate Variability on Calanus Dormancy Patterns and Population Dynamics within the California Current

哲水蚤桡足类是加州海流区的重要生物，以高速率消耗初级和次级生产物，并作为幼体、幼体和小型中上层鱼类、其他无脊椎动物和某些海鸟的猎物。 几种哲水蚤生活中的一个关键时期是它们的越冬期，在此期间，它们在仲夏离开非生产性的表面沃茨，然后在春天上升到表面，通常与春天的水华相一致。然而，物理和生物的线索，都启动和终止休眠期的几个关键桡足类物种在CC知之甚少。 本研究的目的是检验两种主要的哲水蚤物种，哲水蚤太平洋哲水蚤和哲水蚤marshallae的休眠期，在一定程度上是由温度和猎物丰度的变化控制的假设。这一假设将通过两种方法进行检验。首先，现有的相对阶段丰富和垂直分布的两个目标物种的四个不同的位置沿着北美西海岸的数据将被编译和比较观测生物物理数据集，其中许多收集的GLOBEC NEP计划的一部分。第二，基于个人的模型（IBM）的两个物种将开发，基于几个不同的概念模型的温度和猎物的可用性如何控制休眠反应。然后，这个模型将与气候数据相结合，并与实地数据的分析进行比较。此外，该模型将用于测试每个物种的种群动态对初始条件的敏感性，与春季开花时间的相互作用，以及气候变化的预期水平。最后，这两个物种的本地人口丰度的变化，由于当地气候与人口平流的反应，由于大规模的物理运输的变化将得到解决。 这项研究的结果对于了解影响浮游生物主要群体季节性生产的一些基本过程将是重要的。这方面的知识对于了解气候变化对气候变化框架内海洋食物网的总体营养影响至关重要。 这项研究涉及一名博士后学生，从这项工作中获得的信息应证明对小型中上层鱼类和其他受管理的无脊椎物种的渔业管理很有价值。这项研究的结果还将通过一个基于网络的实时访问服务器系统向公众提供，从而使其易于广泛获得。

Calanoid copepods are key organisms in the California Current (CC) region, consuming primary and secondary production at high rates and serving as prey for larval, juvenile, and small pelagic fish, other invertebrates and certain seabirds. A critical period in the life of several calanoid species is their overwintering period, during which they leave the unproductive surface waters in mid-summer to fall and then ascend to the surface in the springtime, usually coincident with the spring bloom. However, the physical and biological cues that both initiate and terminate the dormant phase of several key copepod species within the CC are poorly known. The goal of this research is to test the hypothesis that the dormant phase of two major calanoid species, Calanus pacificus and Calanus marshallae, are in part controlled by changes in temperature and prey abundance. This hypothesis will be tested by two means. First, the existing data on relative stage abundance and vertical distribution of the two target species for four distinct locations along the west coast of North America will be compiled and compared to observational bio-physical datasets, many of which were collected as part of the GLOBEC NEP program. Second, an Individual-Based Model (IBM) for each of the two species will be developed, based on several different conceptual models of how temperature and prey availability control the dormancy response. This model will then be forced with climatological data and compared with the analysis of the field data. Further, this model will be used to test the sensitivity of each species' population dynamics to initial conditions, interaction with the timing of the spring bloom, and expected levels of climate variability. Finally, variability in the local population abundance of these two species due to responses to local climate versus population advection due to large-scale changes in physical transport will be addressed. The results of the research will be important for understanding some of the basic processes that influence the seasonal production of a major group of plankton. This knowledge is critical for understanding the overall trophic impact of climate change on marine food webs within the CC. This research involves a postdoctoral student and the information gained from this work should prove valuable to fisheries management for small pelagics and other managed invertebrate species. The results of this research will also be served to the public through a web-based Live Access Server system, thus making it readily and broadly available.