Killer Whales and Sevengill Sharks Revealed as Culprits in Great White Shark Attack

In October 2023, the discovery of a 15-foot great white shark washed ashore in southeastern Australia shocked scientists and the public alike. The shark's body bore mysterious bite wounds and was stripped of its internal organs, raising questions about the identity of its attackers. Recent DNA analysis has unveiled that both killer whales, or orcas, and broadnose sevengill sharks were responsible for this gruesome attack.

Scientists conducted a thorough investigation, collecting 15 swabs of genetic material from four distinct bite wounds on the shark's body. The analysis confirmed that killer whales inflicted a significant 20-inch wound, consistent with the bite marks observed on the carcass. Meanwhile, DNA from broadnose sevengill sharks was found in three smaller wounds. The findings, published in the scientific journal Ecology and Evolution, offer new insights into the behavior of these marine predators.

"The carcass sparked significant attention from the public due to its size, bite marks, and the speculation of it being the result of a killer whale predation,"

• Journal (Ecology and Evolution)

This revelation has shed light on the predatory practices of killer whales, particularly their selective consumption of shark livers. Similar attacks have been documented in South Africa over the past decade, suggesting a broader pattern of killer whale predation on sharks than previously understood. The study highlights that such attacks are more globally prevalent than initially assumed.

“These results provide confirmed evidence of killer whale predation on white sharks in Australia and the likely selective consumption of the liver, suggesting predations of this nature are more globally prevalent than currently assumed,”

• Report (Ecology and Evolution)

The gruesome nature of the attack underscores the complex dynamics within the marine ecosystem. The collaborative efforts of killer whales and sevengill sharks in targeting the great white shark reveal intricate interspecies interactions that warrant further investigation. These findings have profound implications for our understanding of marine life and predator-prey relationships.