U.S.-GLOBEC NEP Phase IIIb-CGOA: Environmental influences on Growth and Survival of Southeast Alaska Coho Salmon in Contrast with Other Northeast Pacific Regions

尽管GLOBEC NEP在1999/2000年进行了实地抽样、回顾性分析和建模、强有力的比较成分和对环境变化的观察，但仍然缺乏对鲑鱼丰度的预测性了解。尽管与(1)鱼类存活的年变异性和(2)幼鱼的空间分布相关的物理/生物条件是可以描述的，但解释它们的潜在机制以及两者之间的联系都不为人所知。本提案旨在通过使用一种比较的方法来实现理解和可预测性，同时综合了几种银鲑的数据集。GLOBEC在阿拉斯加东南部（SEAK）和加州洋流系统（CCS）对该物种进行了研究，其丰度在两个系统中呈负相关变化。本报告将描述在SEAK进行的GLOBEC nep资助的研究中发现幼鲑的生物/物理条件，以及在一个地点8年和在另一个地点4年期间幼鲑栖息地的变化。一个基于个体的模型将被用来评估这些栖息地对幼鲑生长和死亡的优势，并描述个体鲑鱼如何与这种空间分布相互作用。GLOBEC-NEP资助的一项关于潜在捕食者缓冲效应的回顾性研究的结果将在时间和空间上得到扩展。将根据当地的风和一般环流，拟订具有重要生物学意义的当地物理条件指标，以研究西风流分岔以北海岸个别鱼类的反应。跨越两个系统的编码线标签数据集将与NEP中的GLOBEC观测数据一起使用，以得出在两个系统中一致的coho salmon早期生活史模型，但每个系统可能有不同的物理强迫。这个项目的最终产品是一个每年海洋状况的指标，影响鲑鱼的生存和产卵年龄。这一指标将在短期内直接用于渔业管理，而在长期内则可减少对影响鲑鱼生命周期淡水阶段的因素进行管理的不确定性和争议性。该项目包括一名研究生和一名博士后。

A predictive understanding of salmon abundance is still lacking despite GLOBEC NEP's program of field sampling, retrospective analysis and modeling, a strong comparative component and observation of an environmental shift in 1999/2000. Although the physical/biological conditions associated with (1) annual variability in fish survival, and (2) the spatial distribution of juveniles, are amenable to description, neither the underlying mechanisms to explain them nor the link between two are known. This proposal aims to achieve both understanding and predictability by using a comparative approach while synthesizing several data sets for coho salmon. This species was studied by GLOBEC in both Southeast Alaska (SEAK) and the California Current System (CCS), and its abundance covaries inversely in the two systems. The biological/physical conditions under which juvenile coho salmon were found in GLOBEC NEP-funded studies in SEAK and the variation of the juvenile salmon habitat over 8 years at one location and 4 years at another will be described. An individual-based model will be employed to assess the advantages of these habitats to growth and mortality of juvenile coho salmon, and to describe how individual salmon could interact with such spatial distributions. The findings of a GLOBEC-NEP funded retrospective study regarding potential predator buffering effects will be extended in time and space. Local indicators of biologically important physical conditions, based on local winds and general circulation, will be developed to study the response of individual stocks along the coast north of the bifurcation of the West Wind Drift (WWD). The coded wire tag data set, which spans both systems, will be used together with GLOBEC observations in the NEP to derive a model of coho salmon early life history that is consistent across the two systems, but can have different physical forcing in each.The ultimate product of this project is an indicator of annual ocean conditions that affect salmon survival and age of spawning. This indicator will be directly useful in the short term in fishery management and in the long term by reducing the uncertainty and contentiousness surrounding management of factors influencing the freshwater phase of the salmon lifecycle. This project includes a graduate student and a postdoc.