Animation of tagged southern right whale and vessel traffic

This animation, embedded in the html, shows the satellite tag derived movements of the southern right whale (black track) and the Automatic Identification System (AIS) derived movements of vessels in the region (red tracks; Australian Marine Safety Authority Craft Tracking System). The whale track was interpolated to match the hourly time stamp of the AIS data (see Methods and Materials: Satellite sensor, track and ship movement analysis). The date and time for each frame (top, centre) is 'year-month-day hour:min:sec' in UTC.As part of a multi-year study of inshore movements and offshore foraging ground locations, we biopsied and satellite tagged southern right whales in Flinders Bay, Augusta, Western Australia in September 2022. Here we focus on a female with calf tagged on 9 September 2022. A transdermal Wildlife Computer SPOT-372 satellite tag that provides data on location and water temperature was deployed. To account for the spatial error associated with satellite tag derived Argos locations, we fitted a correlated random walk model using the fit_ssm function from the R package aniMotum (Jonsen et al., 2023) and estimated new locations at each of the original observed Argos location times. Travel speed was calculated using the distance (distanceTrack function from the argosfilter package; Freitas et al., 2008) and the time difference (difftime function in base R) between two consecutive locations. Vessel tracking data were downloaded from the Australian Marine Safety Authority (AMSA) Craft Tracking System (CTS). CTS collects vessel traffic data from a variety of sources, including terrestrial and satellite shipborne Automatic Identification System (AIS) data sources. We extracted vessel traffic data for the months from May to November 2022. The dataset covers the extent of Australia’s Search and Rescue Region. The southern right whale track was interpolated to match the hourly time stamp of the AIS data using the align_move function (package: moveVis (version: 0.10.5; Schwalb-Willmann et al., 2020)) and the distance between the whale and vessel locations calculated using the pointDistance function (package: raster (Hijmans R, 2023)) in R. Jonsen, I.D., Grecian, W.J., Phillips, L., Carroll, G., McMahon, C., Harcourt, R.G., Hindell, M.A., and Patterson, T.A. (2023). aniMotum, an R package for animal movement data: Rapid quality control, behavioural estimation and simulation. Methods Ecol. Evol. 14(3): 806-816. [Available at: https://doi.org/10.1111/2041-210X.14060] Freitas, C., Lydersen, C., Fedak, M., and Kovacs, K.M. (2008). A simple new algorithm to filter marine mammal Argos locations. Mar. Mammal Sci. 24: 315-325. [Available at: https://doi.org/10.1111/j.1748-7692.2007.00180.x] Schwalb-Willmann, J., Remelgado, R., Safi, K., and Wegmann, M. (2020). moveVis: Animating movement trajectories in synchronicity with static or temporally dynamic environmental data in R. Methods. Ecol. Evol. 11: 664-669. [Available at: https://doi.org/10.1111/2041-210X.13374] Hijmans, R.J. (2023). raster: Geographic Data Analysis and Modeling. R package version 3.6-26. Also see 'Harcourt, R., Sprogis, K., Gales, N.J., Andrews-Goff, V., Double, M., Besier, S., Riekkola, L., and Carrol, E.L. (2025). Stranding of a satellite-tagged southern right whale off southwest Australia. J. Cetacean Res. Manage. Special Issue 5: 45-64' for further detail.

本内嵌于HTML网页的动画展示了南露脊鲸（southern right whale）通过卫星标记获取的移动轨迹（黑色轨迹），以及该海域内船舶基于自动识别系统（Automatic Identification System, AIS）得到的航行轨迹（红色轨迹；数据来自澳大利亚海事安全局船舶追踪系统（Australian Marine Safety Authority Craft Tracking System））。鲸类轨迹经插值处理，以匹配AIS数据的小时时间戳（详见方法与材料：卫星传感器、轨迹与船舶运动分析）。每一帧（顶部、中部）的日期与时间采用协调世界时（UTC）格式，标注为「年-月-日 时:分:秒」。

作为近岸移动与近海觅食地定位多年研究的一部分，研究团队于2022年9月在澳大利亚西部奥古斯塔的弗林德斯湾对南露脊鲸开展皮肤活检并部署卫星标记。本研究聚焦于2022年9月9日被标记的一头带崽雌性南露脊鲸。研究团队部署了一款透皮式Wildlife Computer SPOT-372卫星标记设备，可采集位置与水温数据。

为校正卫星标记获取的Argos定位数据的空间误差，研究团队使用R语言包aniMotum中的fit_ssm函数构建了相关随机游走模型，并基于原始Argos定位的观测时间估算了新的位置点。移动速度通过相邻两个定位点之间的距离（使用argosfilter包的distanceTrack函数计算；Freitas等，2008）与时间差（使用基础R包的difftime函数）计算得出。

船舶追踪数据下载自澳大利亚海事安全局（Australian Marine Safety Authority, AMSA）船舶追踪系统（Craft Tracking System, CTS）。CTS从多种渠道采集船舶交通数据，包括地面与星载船载自动识别系统（AIS）数据源。研究团队提取了2022年5月至11月的船舶交通数据。本数据集覆盖澳大利亚搜救区域的全部范围。

研究团队使用R语言中moveVis包（版本0.10.5；Schwalb-Willmann等，2020）的align_move函数对南露脊鲸轨迹进行插值，以匹配AIS数据的小时时间戳，并使用raster包（Hijmans R, 2023）的pointDistance函数计算鲸类与船舶定位点之间的距离。

参考文献：
Jonsen等（2023）。aniMotum：一款用于动物运动数据分析的R语言包：快速质控、行为估算与模拟。《生态学与进化方法》，14(3)：806-816。[可访问：https://doi.org/10.1111/2041-210X.14060]
Freitas等（2008）。一种用于过滤海洋哺乳动物Argos定位数据的简易新算法。《海洋哺乳动物科学》，24：315-325。[可访问：https://doi.org/10.1111/j.1748-7692.2007.00180.x]
Schwalb-Willmann等（2020）。moveVis：在R语言中实现运动轨迹与静态或时变环境数据的同步动画。《生态学与进化方法》，11：664-669。[可访问：https://doi.org/10.1111/2041-210X.13374]
Hijmans, R.J.（2023）。raster：地理数据分析与建模。R语言包版本3.6-26。

如需更多细节，亦可参考Harcourt等（2025）的研究：澳大利亚西南部近海一头卫星标记南露脊鲸的搁浅事件。《鲸类研究与管理杂志》特刊5：45-64。