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

Calanoid桡足类是加利福尼亚海流（CC）地区的关键生物，以高速率消耗初级和次级产品，并成为幼虫，幼鱼，小型远洋鱼类，其他无脊椎动物和某些海鸟的猎物。一些类calanoid物种生命中的一个关键时期是它们的越冬期，在此期间，它们在仲夏离开贫瘠的地表水，然后在春季上升到水面，通常与春季开花同时发生。然而，CC内几个关键的桡足类物种的休眠阶段的启动和终止的物理和生物线索尚不清楚。本研究的目的是验证一种假设，即两种主要的类Calanus pacificus和Calanus marshallae的休眠阶段在一定程度上受温度和猎物丰度的变化控制。这一假设将通过两种方法来检验。首先，将对北美西海岸四个不同地点的两种目标物种的相对阶段丰度和垂直分布的现有数据进行汇编，并与观测生物物理数据集进行比较，其中许多数据集是作为GLOBEC NEP计划的一部分收集的。其次，将基于温度和猎物可用性如何控制休眠反应的几个不同概念模型，为这两个物种开发一个基于个体的模型（IBM）。然后，这个模型将与气候数据进行比较，并与对野外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，以及预期的气候变化水平。最后，将讨论这两种物种在当地种群丰度的变化，这是由于对当地气候的响应，而不是由于物理运输的大规模变化而导致的种群平流。这项研究的结果对于了解影响主要浮游生物群体季节性生产的一些基本过程将是重要的。这些知识对于理解气候变化对海洋食物网的整体营养影响至关重要。这项研究涉及一名博士后，从这项工作中获得的信息应该对小型远洋动物和其他受管理的无脊椎动物物种的渔业管理有价值。这项研究的结果也将通过基于网络的实时访问服务器系统向公众提供，从而使其易于广泛使用。

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.