Ichthyoplankton survey in Oshoro-maru cruise (C040) 2017

Ichthyoplankton survey was conducted in the northern Bering Sea adjacent to the Bering Strait and St. Laurence Island, on July 9-22, 2017, onboard the T/S Oshoro-maru (Hokkaido University). Ichthyoplankton was collected by bongo net (0.7 m diameter, 0.505 mm mesh), MOHT (Matsuda-Oozeki-Hu-Trawl net; 2 m2 mouth opening, 1.4 mm mesh), and ring larvae net (1.3 m diameter, 2.0 and 0.33mm mesh). Of these, bongo and MOHT nets were towed obliquely from surface to 15 m and 10 m above the sea floor, respectively. The ring net was towed sea surface horizontally for 10 min.2017年7月9日至22日，研究团队在毗邻白令海峡与圣劳伦斯岛的白令海北部海域，搭乘北海道大学所属的“大朝丸”号（T/S Oshoro-maru）调查船开展了鱼类浮游幼体（Ichthyoplankton）调查。本次调查采用三类网具采集样本：邦戈网（bongo net，直径0.7米，网目尺寸0.505毫米）、松田-大関-胡拖网（MOHT，口开度2平方米，网目尺寸1.4毫米）以及环形幼体网（ring larvae net，直径1.3米，网目尺寸分别为2.0毫米与0.33毫米）。其中，邦戈网与MOHT拖网分别以斜拖方式作业，前者从海面表层拖至距海底15米处，后者从海面表层拖至距海底10米处；环形幼体网则在海面以水平方式拖曳10分钟。