CTD Data from the toothfish fishery at Heard Island and McDonald Island

Australian vessels fishing in the Commonwealth managed fishery for Patagonian Toothfish and mackerel icefish in the Heard Island and MacDonald Island area deployed conductivity, temperature and depth (CTD) loggers attached to their fishing gear. In most cases CTDs were deployed on demersal longlines but in some cases they were attached to trawl nets and traps.
Data were collected on five fishing vessels during the fishing seasons of 2019/20 and 2020/21

The data were collected with a CTD (Conductivity, Temperature and Depth Recorder) from the Sea Mammal Research Unit (SMRU) at St Andrew’s University Scotland. Files were downloaded with their TagConfig software in text (.txt) format. Recordings were made at (typically) 1 second intervals for the duration of the fishing event, recording data throughout the water column while setting the gear, then while fishing on the sea floor and again through the water column when the gear was retrieved. Each data file has data on date/time, pressure referenced to surface pressure (dbar), absolute pressure (dbar), temperature (°C), conductivity *mS/cm) and salinity (psu). The data are currently not linked to geographical coordinates which are confidential, but these may be able to be released on contact with the data owner and subject to appropriate confidentiality arrangements.
Number of deployments:
2019/20: 25
2020/21: 27

澳大利亚籍渔船在赫德岛（Heard Island）与麦克唐纳岛（MacDonald Island）海域的英联邦共管捕捞作业区，开展巴塔哥尼亚齿鱼（Patagonian Toothfish）及南极冰鱼（mackerel icefish）的捕捞作业，期间将电导-温度-深度（Conductivity, Temperature and Depth, CTD）记录仪安装于捕捞装备之上。多数情况下，CTD记录仪被部署于底层延绳钓渔具，部分场景下则挂载于拖网与诱捕笼中。本次数据采集覆盖2019/20及2020/21两个捕捞季，共涉及5艘作业渔船。

本次采集所用CTD（电导-温度-深度记录仪）由苏格兰圣安德鲁斯大学海洋哺乳动物研究部（Sea Mammal Research Unit, SMRU）提供，数据文件通过其配套的TagConfig软件以纯文本（.txt）格式导出。数据采集频率通常为1秒1次，全程覆盖完整捕捞作业周期：包括下放渔具过程中的水体剖面监测、渔具就位海底作业阶段的连续记录，以及回收渔具过程中的水体剖面复测。每份数据文件包含以下字段：日期/时间、以表面压力为基准的压力值（单位：分巴，dbar）、绝对压力（单位：分巴，dbar）、温度（单位：摄氏度，°C）、电导率（单位：毫西门子每厘米，mS/cm）以及盐度（单位：实用盐度单位，psu）。当前数据暂未关联保密的地理坐标信息，但经与数据所有者联系并达成合规保密协议后，可申请解锁相关坐标数据。

布放次数：
2019/20捕捞季：25次
2020/21捕捞季：27次