How Orcas Killing Great White Sharks Could Disrupt the Fishing Industry


A paper published Friday in the African Journal of Marine Science detailed the event, which occurred in June 2023 off the coast of South Africa.

The research team watched as a male killer whale known as Starboard approached the juvenile white shark and “gripped the left pectoral fin of the shark and thrust forward with the shark several times before eventually eviscerating it,” the study said, adding: “Remarkably, the period from seizing the shark by the pectoral fin to eviscerating it lasted less than 2 minutes.”

Shortly after the attack, researchers on another boat captured photos of Starboard with “a bloody piece of peach-colored liver in its mouth,” according to the paper.

Starboard has been observed killing white sharks in the past however, he usually hunts with a male companion named Port. The study said Port was present during the attack, but he kept his distance, and Starboard acted alone.

The orcas have been hunting white sharks and eating their livers off the coast of South Africa for years. Rare drone footage captured for Discovery Channel’s Shark Week in 2022 showed killer whales preying on a white shark.

But the lone orca attack was a rarer phenomenon.

“This sighting revealed evidence of solitary hunting by at least one killer whale, challenging conventional cooperative hunting behaviors known in the region,” Alison Towner, lead author on the study and a doctoral researcher at Rhodes University, told CNN.

In a video post of the incident shared by the Earth Legacy Foundation, Towner said the predation “represents unprecedented behavior underscoring the exceptional proficiency of the killer whale.”

Researchers say much is still unknown about the larger ecosystem implications of shark-hunting killer whales.

In 2022, another study published by the African Journal of Marine Science, for which Towner was also the lead author, suggested white sharks were fleeing a common aggregation site off South Africa because of the killer whales.

But scientists still don’t know exactly where those white sharks are going.

“As they relocate, they might end up overlapping with heavy commercial fisheries,” Towner told CNN.

A study published in October in the journal Ecological Indicators suggested that some of the white sharks migrated east of the area where they were being hunted by orcas.

The loss of white sharks in South Africa’s waters could also impact tourism, as visitors from all over the world travel to the area to observe the predators.

“Over two decades of annual visits to South Africa, I’ve observed the profound impact these killer whales have on the local white shark population,” Primo Micarelli, a marine biologist and an author on the paper, told CNN.

“Despite my awe for these predators, I’m increasingly concerned about the coastal marine ecology balance,” he added.



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