Pacific salmon survey from research vessel Hokko Maru in the North Pacific from 2023-07-18 to 2023-07-31, cancelled science program (NCEI Accession 0281868)

This cruise was dedicated to salmon survey in the North Pacific, but its scientific program was cancelled due to COVID-19 outbreak on board of the ship on the way to the Bering Sea. No data are expected.

Original cruise plans are as follows. Pacific salmon (Oncorhynchus spp.) is one of the most important fishery resources in the North Pacific. Japanese research vessels have monitored the condition of Pacific salmon stocks since 1952. The current R/V Hokko maru was launched in 2004 and the salmon research cruise using a surface trawl in the summer Bering Sea has been carried out since 2007. The main objective for this cruise is to conduct the annual monitoring survey for Japanese chum salmon (O. keta) stocks in the Bering Sea known as their major feeding ground. A positive correlation between annual CPUE of immature chum salmon in each research cruise and a subsequent harvest along Japanese coasts of the corresponding blood-year stocks has found in most cases to date, suggesting the possibility to predict future resource conditions. The annual monitoring survey includes the collection of data on physical oceanography, trophic interactions among zooplankton, salmonids, and organisms at higher trophic levels, and genetic analysis of stock composition of chum salmon.

This dataset is U.S. State Department MSR U2023-004 as part of the World Data Service for Oceanography. Cruise reports are in PDF.

本航次原计划于北太平洋开展鲑鱼调查，但在前往白令海途中因船上暴发新冠肺炎疫情，其科学计划被迫取消，预计无有效观测数据产出。
航次原定计划如下：太平洋鲑鱼（*Oncorhynchus* spp.）是北太平洋最重要的渔业资源之一。自1952年起，日本研究船便持续监测北太平洋鲑鱼种群的资源状况。现役的R/V Hokko Maru号研究船于2004年下水，自2007年起，该船每年夏季均在白令海开展使用表层拖网的鲑鱼研究航次。本次航次的核心目标为在白令海——日本狗鲑（*O. keta*）的主要索饵场——开展针对该种群的年度监测调查。截至目前，多数研究案例均已证实：各航次中未成熟狗鲑的年度单位捕捞努力量渔获量（Catch Per Unit Effort, CPUE），与对应同生年种群在日本沿岸的后续捕捞产量之间存在显著正相关，这表明可通过本次监测预测未来的渔业资源状况。本次年度监测调查内容涵盖物理海洋学数据采集、浮游动物、鲑形目鱼类及更高营养级生物间的营养级互作研究，以及狗鲑种群组成的遗传学分析。
本数据集隶属于美国国务院MSR U2023-004项目，为世界海洋学数据服务（World Data Service for Oceanography）的组成部分。航次报告以PDF格式存储。