3-Dimensional trajectories and positioning of individuals within an Antarctic krill swarm in the Southern Ocean - data from the TEMPO voyage of the RV Investigator

This metadata record describes the 3-Dimensional coordinates of individual krill obtained from the ‘Swarm study’ at-sea deployment of stereo-cameras. An array of 10 Gopro Hero-8 cameras (2 cameras on each lateral side of a cubic frame, and a pair on the bottom) was deployed into a krill swarm during the 2021 TEMPO (Trends in Euphausiids off Mawson, Predators, and Oceanography) voyage onboard the RV Investigator (see Kelly et al. 2021 for more details on the voyage). The primary goal of TEMPO was to collect data to estimate krill biomass with a view to update the precautionary catch limit for krill in CCAMLR’s Division 58.4.2-East. The aim of the Swarm study was to replicate the methods of Burns et al., 2023, in order to examine the individual level behaviour of krill in swarms in natural conditions. The TEMPO voyage ran from February to March 2021. The Swarm study system was deployed when a krill swarm was identified from the ships echosounder and weather and sea conditions allowed for filming (i.e. minimal to no wind or swell, full sun).

This data product contains coordinates of individual krill in three dimensions from a pair of stereo cameras. There are 2 datasheets: TEMPO_Orientation TEMPO_Tracks TEMPO_Orientation: this dataset contains the head and tail coordinate of 305 individual krill obtained from videos deployed into a krill swarm date: date video obtained deployment: deployment no. of swarm study panel: panel cameras attached to (for video ID) left/rightcam: for ID camera_dist: horizontal distance between the two cameras left/rightvid: video filename framediff: difference in frames between left and right camera still: still photo reference number that orientation data was obtained from frame (leftvid): corresponding frame for still pointref: point of krill where coordinate (head or tail) id: individual krill x1/y1: xy coordinates from left camera x2/y2: xy coordinates from right camera convertedXYZ: converted coordinates into 3Dimensional TEMPO_Tracks date: date video obtained deployment: deployment no. of swarm study panel: panel cameras attached to (for video ID) left/rightcam: for ID camera_dist: horizontal distance between the two cameras left/rightvid: video filename framediff: difference in frames between left and right camera fps: video frame rate per second clip: clip reference number frame: clip frame reference pointref: point of krill where coordinate (head or tail) x1/y1: xy coordinates from left camera x2/y2: xy coordinates from right camera on separate tabs: clip#: matched pairs of XY coordinates from the 2 cameras clip#XYZ: corresponding converted XYZ coordinates

References
Burns, A.L., Schaerf, T.M., Lizier, J., Kawaguchi, S., Cox, M., King, R., Krause, J. and Ward, A.J., 2022. Self-organization and information transfer in Antarctic krill swarms. Proceedings of the Royal Society B, 289(1969), p.20212361.

Kelly, N., Bestley, S., Burns, A., Clarke, L., Collins, K., Cox, M., Hamer, D., King, R., Kitchener, J., Macaulay, G., Maschette, D., Melvin, J., Miller, B., Smith, A., Suter, L., Westwood, K., Wotherspoon, S. and Kawaguchi, S. (2021). An overview of the ecosystem survey to quantify krill abundance for krill monitoring and management in Eastern Sector of CCAMLR Division 58.4.2: Trends in Euphausiids off Mawson, Predators, and Oceanography “TEMPO”, Working Group on Ecosystem Monitoring and Management, CCAMLR, WG-EMM-2021/07, 26pp.

本元数据记录描述了"Swarm study（群体研究）采用立体相机海上部署所获取的南极磷虾个体三维坐标。本次部署了10台GoPro Hero-8相机：在立方框架的每个侧面各安装2台相机，底部安装1对相机，于2021年TEMPO航次（全称Trends in Euphausiids off Mawson, Predators, and Oceanography，即莫森海域磷虾、捕食者与海洋学趋势）期间，搭载于RV Investigator（调查者号）科考船投放至磷虾群体中，相关航次细节详见Kelly等2021年的研究成果。

该航次的核心目标为收集数据以估算磷虾生物量，以期更新CCAMLR（南极海洋生物资源养护委员会）58.4.2-East区域内磷虾的预防性捕捞限额。本次"Swarm study（群体研究）旨在复刻Burns等2023年的研究方法，以探究自然环境下磷虾群体中个体的行为特征。TEMPO航次的执行时间为2021年2月至3月。当科考船回声探测仪识别到磷虾群体，且天气与海况满足拍摄条件（即无风或涌浪极小、日照充足）时，部署本次群体研究系统。

本数据产品包含来自一对立体相机的三维空间内的单个磷虾坐标。本次数据集包含2个数据表：TEMPO_Orientation与TEMPO_Tracks。

### TEMPO_Orientation数据表：该数据集包含从投放至磷虾群体的视频中获取的305只个体磷虾的头部与尾部坐标。各字段含义如下：
date：视频获取日期；
deployment：群体研究面板的部署编号；
panel：所连接的相机面板（用于视频ID标识）；
left/rightcam：用于标识相机的编号；
camera_dist：两台相机之间的水平间距；
left/rightvid：视频文件名；
framediff：左右相机之间的帧差；
still：获取定向数据所参考的静态照片编号；
frame (leftvid)：静态参考点对应的左相机视频帧；
pointref：对应坐标的磷虾身体部位（头部或尾部）；
id：单个磷虾的唯一标识编号；
x1/y1：左相机采集的xy平面坐标；
x2/y2：右相机采集的xy平面坐标；
convertedXYZ：转换得到的三维空间坐标。

### TEMPO_Tracks数据表：各字段含义如下：
date：视频获取日期；
deployment：群体研究面板的部署编号；
panel：所连接的相机面板（用于视频ID标识）；
left/rightcam：用于标识相机的编号；
camera_dist：两台相机之间的水平间距；
left/rightvid：视频文件名；
framediff：左右相机之间的帧差；
fps：每秒视频帧率；
clip：剪辑片段的参考编号；
frame：剪辑片段的帧参考编号；
pointref：对应坐标的磷虾身体部位（头部或尾部）；
x1/y1：左相机采集的xy平面坐标；
x2/y2：右相机采集的xy平面坐标。
在单独的标签页中：
clip#：两台相机匹配得到的XY坐标配对数据；
clip#XYZ：对应的转换后三维空间坐标。

参考文献
1. Burns, A.L., Schaerf, T.M., Lizier, J., Kawaguchi, S., Cox, M., King, R., Krause, J. 及 Ward, A.J.，2022年。《南极磷虾群体中的自组织与信息传递》，发表于《英国皇家学会学报B辑》，289(1969)，文章编号20212361。
2. Kelly, N., Bestley, S., Burns, A., Clarke, L., Collins, K., Cox, M., Hamer, D., King, R., Kitchener, J., Macaulay, G., Maschette, D., Melvin, J., Miller, B., Smith, A., Suter, L., Westwood, K., Wotherspoon, S. 及 Kawaguchi, S.，2021年。《CCAMLR 58.4.2东部区域磷虾监测与管理的磷虾丰度量化生态调查概述：莫森海域磷虾、捕食者与海洋学趋势（TEMPO）》，载于南极海洋生物资源养护委员会生态监测与管理工作组报告，WG-EMM-2021/07，共26页。