Abstract
Scavenging is an important component to the overall ecology of consumers in virtually all ecosystems on Earth. Given the energetic benefits of foraging on these resource subsidies, opportunistic predators will adjust their behaviors accordingly to maximize access. One of the many consequences of large-scale scavenging opportunities is species interactions that are rarely observed in nature. Here we describe the first published record of predatory sharks (tiger sharks, Galeocerdo cuvier) and saltwater crocodiles (Crocodylus porosus) foraging together in space and time, as documented on a large whale carcass off Western Australia. We report on and discuss the behaviors of the sharks and crocodiles in the hope of shedding new light on the interactions between apex predators that are rarely seen together, but may overlap under specific contexts.
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Acknowledgements
Thank you to Jeremy Tucker for obtaining and sharing the drone footage, as well as the staff of Great Escape Charters for assisting with the event. The authors declare that they have no conflict of interest. This article does not contain any studies with animals performed by any of the authors.
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Gallagher, A.J., Papastamatiou, Y.P. & Barnett, A. Apex predatory sharks and crocodiles simultaneously scavenge a whale carcass. J Ethol 36, 205–209 (2018). https://doi.org/10.1007/s10164-018-0543-2
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Keywords
- Behavior
- Carcass
- Saltwater crocodile
- Predator
- Tiger shark
- Whale