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, andiii) 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., Sonar tags were deployed for a week 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 (Goulet et al. 2019). The individuals are identified respectively as #314a, #314b and #315a. The sonars tags also included 3D acceleration and magnetometry sensors providing unprecedented data to document the approach and pursuit of prey by predators. Deployment started on November 11th (2 individuals) and November 12th (1 individual) and ended on November 17th and 18th (7 days deployment) respectively. Females were temporarily captured with a canvas head-bag and anesthetized with a 1:1 combination of Tiletamine and Zolazepam (Zoletil), at a dosage of 0.5 mg.kg-1 (Wheatley et al. 2006). Seals were monitored until fully recovered from anaesthesia and were allowe..., , # 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.

## Abstract

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,

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.

## Description of the data and file structure

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