U.S.-GLOBEC: NEP Phase IIIb-CGOA: Habitat effects on feeding, condition, growth and survival of juvenile pink salmon in the northern Gulf of Alaska

U.S.-GLOBEC：NEP IIIb-CGOA：栖息地对阿拉斯加湾北部粉红鲑鱼幼鱼的摄食、状况、生长和生存的影响

• 批准号: 0535393
• 负责人: Lewis Haldorson
• 金额: $ 64.33万
• 依托单位: University of Alaska Fairbanks Campus
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-01-01 至 2009-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0535393&HistoricalAwards=false
• 关键词: U.S.; GLOBEC; NEP; Phase; IIIb

The northeast Pacific Ocean is of increasing oceanographic interest as observations of decadal-scale fluctuations in salmon abundance appear linked to basin-wide changes in meteorological forcing and oceanographic conditions. These regime shifts indicate that climate changes are quickly expressed in biological productivity, although the mechanisms that alter ecosystem structure and function are not well documented. Pink salmon are particularly suited to serve as indicators of marine conditions, as they are abundant and have a short, two-year life cycle with non-overlapping generations. Juvenile pink salmon from Prince William Sound (PWS) hatcheries carry thermal otolith marks that allow estimates of both growth in their early marine phase and of overall cohort survival, thus providing an exceptional opportunity to study the effects of habitat quality. Thus project uses data from four programs that sampled juvenile pink salmon in the northern GOA to estimate feeding intensity, condition, and growth for each hatchery cohort by time and habitat. The occurrence of favorable habitats (i.e. where juvenile pink salmon were feeding well, were in good condition, and exhibited fastest growth) will be identified, allowing description of their characteristics.Since mortality of juvenile salmon is reduced in larger individuals, feeding, condition and growth is determined in upper size-based quantiles as characteristics of larger, faster-growing individuals may present better indicators of habitat quality than overall means or medians. This synthesis strategy is a top-down approach, as it is the fish that decide where and when favorable habitats occurred. Mechanistic understanding of the processes by which climate and oceanographic conditions affect marine ecosystems and salmon production is still lacking. The OptimalStability Hypothesis (OSH) suggests that, in the northern GOA, increased water column stability during summer enhances primary production and zooplankton abundance; leading to enhanced feeding, growth and survival of juvenile salmon. Water column stability, depth distribution of chlorophyll, light availability at depth, zooplankton abundance and salmon response variables (feeding, condition and growth) are examined to determine significant inter-relationships among them, and their bearing on the OSH.This project will lead to the development of a comprehensive database for pink salmon juveniles, compiled from four projects. A Ph.D. student and a post-doctoral fellow are supported by this work. Scientists at the Alaska Dept. of Fish and Game are providing a data set for the database will benefit from estimates of early marine survival to improve forecasting. The project maintains a strong interaction with an alliance of stakeholders in the PWS salmon fishery. A website developed by that group is used to communicate results of our synthesis research to the broader resource-dependent community of PWS and the northern GOA.

东北太平洋的海洋学兴趣日益浓厚，因为对鲑鱼丰度十年尺度波动的观测似乎与全盆地气象强迫和海洋条件的变化有关。这些格局的转变表明，气候变化很快就体现在生物生产力上，尽管改变生态系统结构和功能的机制还没有得到很好的记录。粉红鲑鱼特别适合作为海洋状况的指标，因为它们数量丰富，生命周期短，为两年，且世代不重叠。来自威廉王子湾 (PWS) 孵化场的幼年粉红鲑鱼带有热耳石标记，可以估计其早期海洋阶段的生长情况和总体存活率，从而为研究栖息地质量的影响提供了绝佳的机会。因此，该项目使用了四个项目的数据，这些项目在果阿北部对幼年粉红鲑鱼进行了采样，以按时间和栖息地估计每个孵化场群体的饲养强度、状况和生长情况。将确定有利的栖息地（即幼年粉红鲑鱼摄食良好、状况良好且生长最快的地方），从而描述其特征。由于个体较大的幼年鲑鱼的死亡率降低，摄食、状况和生长是根据基于体型的上限分位数确定的，因为较大、生长较快的个体的特征可能比总体平均值或中位数更好地反映栖息地质量。这种综合策略是一种自上而下的方法，因为是鱼决定了有利栖息地出现的地点和时间。对于气候和海洋条件影响海洋生态系统和鲑鱼生产的过程的机制仍然缺乏了解。最佳稳定性假说 (OSH) 表明，在 GOA 北部，夏季水体稳定性的增加可提高初级生产力和浮游动物丰度；从而提高幼鲑鱼的摄食、生长和存活率。检查水柱稳定性、叶绿素的深度分布、深度的光可用性、浮游动物丰度和鲑鱼响应变量（摄食、状况和生长），以确定它们之间的重要相互关系及其对职业安全与健康的影响。该项目将导致开发粉红鲑鱼幼鱼综合数据库，由四个项目汇编而成。博士学位学生和博士后研究员受到这项工作的支持。阿拉斯加渔猎部的科学家正在为该数据库提供一个数据集，该数据库将受益于早期海洋生存的估计，以改进预测。 该项目与 PWS 鲑鱼渔业的利益相关者联盟保持着密切的互动。该小组开发的一个网站用于向 PWS 和北部 GOA 更广泛的资源依赖社区传达我们的综合研究结果。