Salmon length, weight, sex, stomach data from F/V Great Pacific, R/V Miller Freeman multiple cruises in the Coastal Gulf of Alaska, NE Pacific from 2001-2004 (NEP project)

<p><strong>GLOBEC 2000: Factors Affecting the Distribution of Juvenile Salmon in the Gulf of Alaska</strong><br /> <em>J. Helle (NMFS/AFSC, Auke Bay Laboratory)</em><br /> <em>E. D. Cokelet (Pacific Marine Environmentla Laboratory),<br /> E. V. Farley, Jr. (NMFS/AFSC, Auke Bay Laboratory),<br /> A. B. Hollowed (NMFS/AFSC),<br /> P. J. Stabeno (Pacific Marine Environmental Laboratory)</em></p> <p>\"Remarkable changes in atmospheric, oceanic and biological conditions have occurred in recent decades in the North Pacific Ocean including declines in the marine survival of some salmon stocks. Fishery scientists generally agree that in the first few months after leaving freshwater, salmon survival and growth are linked to oceanic variability. The purpose of this research is to focus National Marine Fisheries Service studies on the GLOBEC region, augment oceanographic measurements and determine what biological and physical factors influence the distribution of juvenile salmon. Three general hypotheses are explored in this proposal: (1) juvenile salmon prefer the buoyancy-driven Alaska Coastal Current (ACC) at the head of the Gulf of Alaska, (2) they associate with oceanic temperature, salinity, current and prey fields, and (3) they migrate landward of Kodiak Island in the ACC rather than seaward in the Alaskan Stream. Annual, summer cruises aboard a chartered fishing vessel will catch juvenile salmon on 10 transects between Yakutat Bay and Kodiak Island. The vessel will be outfitted with a thermosalinograph to measure sea-surface temperature and salinity, and with an Acoustic Doppler Current Profiler (ADCP) - each operating continuously for fine-scale resolution. Modeled tidal currents will be removed from ADCP measurements to reveal the mean flow fields. At each trawl site, temperature and salinity profiles will provide water-column properties, and bongo-net hauls will give zooplankton distributions. Stomach samples from juvenile salmonids will be analyzed in the laboratory for diet composition and compared with zooplankton distributions. Analysis of salmon otoliths for hatchery thermal marks and Genetic Stock Identification techniques will be used to determine the home stream of hatchery and wild stocks in the Gulf of Alaska and their distribution with respect to oceanographic regimes. Retrospective analysis of catch per unit effort versus oceanographic and prey factors will reveal what affects the distribution of pink, chum, coho and sockeye salmon in the study region. Proxies for bio-physical factors will be developed and compared with salmon-run size.\"<em>(project proposal)</em></p> <p><strong>Data Collection Details:</strong><br /> Types: CTD profiles, ADCP profiles of ocean current, juvenile salmonid catch statistics from trawls, salmonid stomach samples analyzed for diet composition, salmonid otolith analyses, Genetic Stock Identification, zooplankton distributions from bongo-net hauls<br /> Platform: Chartered fishing vessel<br /> Spatial extent: 10 transects perpendicular to the coast between Yakutat Bay and Kodiak Island<br /> Temporal extent: ~2 weeks each July-August of 2001-2004.</p> <p><img alt=\"\" src=\"https://datadocs.bco-dmo.org/static/globec.whoi.edu/images/nep/salmon_spp_photo.jpg\" /></p>**GLOBEC 2000：阿拉斯加湾幼鲑分布的影响因素** *J. Helle（美国国家海洋渔业局/阿拉斯加渔业科学中心，奥克湾实验室）* *E. D. Cokelet（太平洋海洋环境实验室）， 小E. V. Farley（美国国家海洋渔业局/阿拉斯加渔业科学中心，奥克湾实验室）， A. B. Hollowed（美国国家海洋渔业局/阿拉斯加渔业科学中心）， P. J. Stabeno（太平洋海洋环境实验室）* “近数十年来，北太平洋海域的大气、海洋与生物环境发生了显著变化，部分鲑鱼种群的海洋存活率随之下降。渔业科学家普遍认为，鲑鱼在离开淡水后的最初数月内，其存活与生长与海洋环境变率密切相关。本研究旨在将美国国家海洋渔业局的研究聚焦于GLOBEC研究区域，扩充海洋观测手段，并明确影响幼鲑分布的生物与物理因素。本提案探讨了三项核心假说：其一，阿拉斯加湾头部区域的浮力驱动型阿拉斯加沿岸流（Alaska Coastal Current, ACC）为幼鲑的偏好栖息环境；其二，幼鲑的分布与海洋温度、盐度、流场及饵料场相关联；其三，幼鲑会通过阿拉斯加沿岸流（ACC）向科迪亚克岛近岸洄游，而非沿阿拉斯加海流向外海移动。 本研究将在每年夏季租用渔船开展巡航调查，在雅库塔特湾与科迪亚克岛之间的10条断面上采集幼鲑样本。调查船将配备热盐深仪（thermosalinograph）以连续测量海表温度与盐度，并搭载声学多普勒流速剖面仪（Acoustic Doppler Current Profiler, ADCP）实现高精度的连续观测。研究将从ADCP观测数据中移除模拟潮汐流分量，以提取平均流场信息。在每个拖网采样站位，将通过温盐剖面获取水体垂直结构特征，并使用邦戈网（bongo-net）拖捕采集浮游动物样本以分析其分布情况。实验室将对幼鲑的胃含物样本进行分析，明确其饵料组成，并与浮游动物分布数据进行比对。此外，将通过分析鲑鱼耳石的孵化热标记特征，结合遗传种群识别（Genetic Stock Identification, GSI）技术，确定阿拉斯加湾内养殖种群与野生种群的起源溪流，并明确其与海洋环境格局的分布关联。本研究还将通过单位捕捞努力量渔获量（catch per unit effort, CPUE）的回顾性分析，结合海洋环境与饵料因子数据，明确研究区域内粉鲑、大麻哈鱼、银鲑与红鲑的分布影响因素。最终将构建生物-物理因子的替代指标，并与鲑鱼洄游种群规模进行对比分析。”（项目提案） **数据采集详情** 数据类型：CTD剖面、海洋流场ADCP剖面、拖网采集的幼鲑捕捞统计数据、用于饵料组成分析的鲑鱼胃含物样本、鲑鱼耳石分析、遗传种群识别（GSI）、邦戈网拖捕获取的浮游动物分布数据 观测平台：租用渔船 空间范围：雅库塔特湾至科迪亚克岛之间的10条垂直于海岸的断面 时间范围：2001-2004年每年7-8月，每次巡航时长约2周 <img alt="" src="https://datadocs.bco-dmo.org/static/globec.whoi.edu/images/nep/salmon_spp_photo.jpg" />