U.S.-GLOBEC: NWA Georges Bank. Factors determining early-life-stage survival & recruitment variability in N. Atlantic cod: a comparison bewteen NW Atlantic & Norwegian Sea

这项研究通过与海洋研究所（卑尔根）的挪威同事合作，比较了乔治海岸和挪威大陆架/巴伦支海的生态系统。目的是更好地了解鱼类种群和浮游动物之间的相互作用，以及这些相互作用如何受到气候变异和变化的影响。这种理解将被纳入一个模型的鳕鱼招聘通过成人stages.The总体假设是，鳕鱼和黑线鳕的招聘是由在鸡蛋和幼虫阶段，这是由密度和栖息地的依赖性因素的限制生存的变化。两个子假设断言，（Ho 1）平流的斯科舍陆架水到缅因州和（Ho 2）平流的zoobaston-rich水从挪威海到巴伦支海陆架增加幼鳕鱼/黑线鳕的生长和生存在每个系统。该方法包括：1）计算流域尺度上的物理和生物场，以评估两个系统中局部效应与平流/上游效应的相对重要性。(2)在区域范围内实施拉格朗日模型，以量化两个系统中的滞留和运输及其变异性;（3）实施空间明确的基于个体的幼鱼和早期幼鱼生长模型，当与观察到的猎物数据相结合时，将提供两个系统中的生长率。(4)发展一套指数或替代指标，以反映影响生命早期的保存/运输、生长和存活的因素和过程。(5)建立模型，将成年人口的动态与影响补充的物理和生物因素联系起来：通过对西北大西洋/乔治海岸与挪威海系统进行相互比较，可以概括各种方法及其对其他地点的相关性。根据详细的过程研究制定的指数将用于制定、参数化和评价与重要商业鱼种成鱼种群动态有关的混合补充模型。所有结果都将在网上公布，以便感兴趣的学生、教师、科学家或资源管理人员能够加以利用。

This study compares the ecosystems on Georges Bank and the Norwegian shelf/Barents Sea via a collaboration with Norwegian colleagues at the Institute of Marine Research (Bergen). The objective is to develop a better understanding of the interactions between fish populations and zooplankton and how these interactions are influenced by climate variability and change. This understanding will be incorporated into a model of cod recruitment through the adult stages.The overarching hypothesis is that recruitment of cod and haddock is determined by variability in survival during the egg and larval stages, which is constrained by density- and habitat-dependent factors. Two sub-hypotheses assert that (Ho1) advection of Scotian shelf water into the Gulf of Maine and (Ho2) advection of zooplankton-rich water from the Norwegian Sea into the Barents shelf increases larval cod/haddock growth and survival in each system. The approach includes: 1) Computation of physical and biological fields on a basin-scale to evaluate the relative importance of local vs. advective/upstream effects in the two systems. (2) Implementation of Lagrangian models within the regional domains to quantify retention and transport and their variability in the two systems; (3) Implementation of spatially-explicit individual-based models for larval and early juvenile fish growth which, when coupled with the observed prey data will provide growth rates in the two systems. (4) Development of asuite of indices or proxies for factors and processes affecting early-life retention/transport, growth and survival.(5) Development of models linking the dynamics of adult populations with physical and biotic factors affecting recruitment.The inter-comparison of the NW Atlantic/Georges Bank with the Norwegian Sea system, allows for a generalization of the approaches and their relevance to other locations. The development of indices based on the detailed process studies will be used to develop, parameterize and evaluate hybrid recruitment models linked to the dynamics of adult stocks of commercially important species. All results will be made publicly available on the web so that interested students, teachers, scientists or resource managers can make use of them.