Beneath the Antarctic sea-ice: Fine-scale analysis of Weddell seal (Leptonychotes weddellii) behaviour and predator-prey interactions, using micro-sonar data in Terre Adélie

In this study, we tried to assess: i) whether and how female Weddell seals feed (frequency, depth, duration) during lactation, ii) what is their utilization of a limited foraging area (benthic or pelagic dives) as they are spatially constrained by the presence of their pup, and iii) how can we characterize their foraging dives and the approach/catching phases using new tools providing a more detailed description of their behaviour. Sonar tags were deployed on three breeding female Weddell seals in Terre Adélie (East Antarctica) in November 2019, to study animals' movements and dives at high resolution (3D acceleration, magnetometry, time and depth and GPS location), as well as information on prey and predator-prey interactions using acoustic data.

本研究旨在评估以下三项核心内容：其一，雌性威德尔海豹（Weddell seal）在哺乳期的觅食行为，包括其觅食频率、潜水深度与持续时长；其二，由于受幼崽存在的空间约束，这类海豹如何利用有限的觅食区域（如底栖潜水或远洋潜水行为）；其三，如何借助可更细致描述其行为的新型工具，对其觅食潜水行为以及接近、捕获猎物的阶段进行特征刻画。研究团队于2019年11月在南极东部的阿德利地（Terre Adélie），为3只繁殖期雌性威德尔海豹部署了声纳标签（sonar tag），通过高分辨率的3D加速度、磁强计、时间、深度及GPS定位数据，研究该类动物的运动与潜水行为，并利用声学数据获取猎物及捕食者-猎物互动相关信息。