Hunting behaviour of white sharks recorded by animal-borne accelerometers and cameras

ABSTRACT: Hunting large, fast-moving mammals by top predators often involves highly energetic burst locomotion, and studying such behaviour can reveal how physiological capacity shapes predator-prey relationships. Although increasingly sophisticated animal-borne devices have allowed the recording of terrestrial predators’ behaviour (e.g. cheetahs) hunting herbivorous mammals, similar approaches have rarely been applied to marine predators hunting mammals. Here, we deployed video cameras (lasting for 6 h) and accelerometers (lasting for 2 d) on 8 white sharks Carcharodon carcharias aggregating near colonies of long-nosed fur seals Arctocephalus forsteri. Video showed one shark attacking a seal, during which an intensive swimming event (lateral acceleration: 3.7 × g, tailbeat frequency: 3.3 Hz, estimated swim speed: 6.7 m s^-1) was recorded. Based on this confirmed event, 7 potential predation events were identified from 150 h of acceleration data. The events occurred at various depths (0-53 m) and primarily at nighttime and during crepuscular periods, partly contrasting with well documented seal-hunting breaching behaviour that occurs primarily during crepuscular periods. This study demonstrates that, despite inherent difficulties, recording infrequent hunting events of top marine predators provides insight into their hunting strategies and maximum locomotor performance.