Orcas Rip Apart Great White Shark in Rare Attack

A great white shark that washed up dead on a beach in Australia is thought to have been torn to shreds by a pod of orcas.

The shark, found near Cape Bridgewater on the south coast of Victoria, was around 10 feet long and had injuries consistent with an attack by orcas.

The discovery on Tuesday, by a local fisherman, coincided with a pod of killer whales being spotted off the coast, reported radio station ABC South East SA.

Lauren Meyer, a trophic ecologist at Flinders University in Adelaide, said the shark was likely attacked by the orcas in order to get to its liver, a behavior that has been seen on rare occasions in other parts of the world.

Nine similar attacks on great white sharks by orcas have happened around South Africa and the U.S. The orcas will hunt the sharks and precisely remove their livers, one of the fattiest parts of the body, leaving the rest of the carcass.

"We're not actually sure why killer whales are such picky eaters," Meyer told ABC. "We see this with things like humpback whales, where [killer whales] come in and actually eat the tongue and leave the rest of the whale.

"We certainly see that they prefer the liver of white sharks, mako sharks, bronze whalers and sevengills, and even tiger sharks. We also see they like to eat the intestines of sunfish, which is really strange, and dugong intestines."

Great white sharks' livers are high in vitamins too, making them a bountiful meal for an orca.

"Shark livers are rich in lipids and nutrients, often making up a significant portion of the shark's body mass. This makes them a valuable prey item for killer whales," Alison Towner, a shark researcher at Rhodes University in Makhanda, South Africa, told Newsweek.

Not all killer whales do this, however. Some only eat tuna while others eat mammals, depending on the social teachings of the pod.

"In South Africa, the knowledge of killer whales preying on coastal sharks was initially limited to a specific pair," said Towner.

"In 2022, drone footage revealed other killer whales engaging in similar behaviour alongside one of the known pair. While we cannot say whether this behaviour was transferred through cultural transmission—rapid learning known in killer whales—or if it is spreading, ongoing monitoring is in place."

This behavior has had an impact on local ecosystems. In some locations off the coast of South Africa, great white sharks and bronze whaler sharks have been observed avoiding areas where the orcas roam, leaving a gulf at the top of the food chain.

"The decline or displacement of great white sharks, as top predators in ocean ecosystems, can lead to mesopredator release," Towner said.

"In certain areas like South Africa, the absence of white sharks due to displacement by killer whales has increased competition among Cape fur seals and critically endangered African penguins for small pelagic fish."

In Australia, the researchers are now studying the rake marks on the Cape Bridgewater shark's carcass, as well as leftover genetics from the culprits, including saliva.

Meyer has been part of a project creating an international database of shark/orca interactions.

"Killer whales are such mysterious animals because we don't interact with them very often," she said. "They're relatively elusive and each different pod and ecotype has such specific behavior that it's hard to draw conclusions across all killer whales because they all act so differently."

Update 10/19/23, 10:30 a.m. ET: This article was updated to add comments from Alison Towner, a shark researcher at Rhodes University in Makhanda, South Africa.

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