RMT Trawl catch from the 1986/87 V7 AAMBER voyage

This data were collected on the sixth Nella Dan voyage of a long term field survey project being conducted by the Australian Antarctic Division, to collect distribution, abundance and population structure data for the krill Euphausia superba in the Prydz Bay region, Antarctica. A Rectangular Midwater Trawl (RMT 1+8) was used for the collection of … larval and post larval (juvenile and adult) krill Euphausia superba, and other zooplankton. Three haul methods were used. At each station a shallow downward oblique haul was taken from the surface to 200m. At selected stations a deep downward oblique haul from 200m to 1000m was taken to collect early developmental stages of Euphausia superba. When krill swarms were located at particular depths (by a Simrad EK 120 echosounder), specific aimed horizontal tows were made.

本数据集采自澳大利亚南极局（Australian Antarctic Division）实施的长期野外调查项目的第六次“内拉丹号”（Nella Dan）科考航次，旨在采集南极普里兹湾区域南极磷虾（Euphausia superba）的分布、丰度及种群结构相关数据。本次调查采用矩形中层拖网（Rectangular Midwater Trawl，RMT 1+8）采集南极磷虾幼体、后幼体（稚虫与成体）及其他浮游动物样本。本次作业共采用三种拖网采样方式：所有采样站位均开展从海面至200米水深的浅层垂直斜向拖网；部分选定站位则开展从200米至1000米水深的深层垂直斜向拖网，以获取南极磷虾的早期发育阶段个体；当通过Simrad EK 120回声测深仪探测到磷虾群聚集于特定水层时，即开展针对性水平拖网作业。