Lone killer whale gutted a great white shark in a couple of minutes

A pair of killer whales working together have been killing great white sharks along the South African coast since at least 2017, eating the sharks’ nutrient-rich livers and discarding the rest, CNN reports.

Scientists have been trying to understand the hunting approach that has driven sharks away from parts of the coast around Cape Town, and now research has revealed a startling new turn in behavior that could hold clues about what it could mean for the wider marine ecosystem.

Last year, scientists witnessed one of these predators, a male killer whale known as Starboard, single-handedly kill a 2.5-metre juvenile white shark within two minutes.

“In two decades of annual visits to South Africa, I have observed the profound impact these killer whales have on the local white shark population. Seeing Straborde’s liver pass by our vessel is unforgettable,” said Dr. Primo Micarelli, a marine biologist at the Italian Shark Research Center and the University of Siena, who was on board one of the two vessels from which researchers observed the attack.

“While I am in awe of these predators, I am increasingly concerned about the balance of coastal marine ecology,” Micarelli said in a statement.

It is not unprecedented for killer whales, highly intelligent and social animals, to hunt large animals individually. However, this is the first such case involving one of the world’s largest predators, the great white shark, researchers said in a study published Friday in the African Journal of Marine Science.

Starboard’s killing contradicts the more widely observed cooperative hunting behavior of killer whales, which can surround large prey such as sea lions, seals and sharks and use their combined intelligence and strength to attack, said lead author Alison Towner, a doctoral researcher at Rhodes University.

Previously observed attacks on great polar bears involved two to six killer whales and took up to two hours to complete, according to the study.

“This observation revealed evidence of solitary hunting by at least one killer whale, which challenges traditional communal hunting behavior known in the region,” notes Alison Towner, who has studied great white sharks for 17 years, learning about their movement patterns through tagging data.

“This is a groundbreaking understanding of the predatory behavior of this species,” she said. “The presence of these shark-hunting killer whales may be related to broader ecosystem dynamics. The rapid development of this phenomenon makes it difficult for science to keep up with the times.”

The event detailed in the study occurred on June 18, 2023, 800 meters offshore near Seal Island off Mossel Bay – about 400 kilometers east of Cape Town – where people on two vessels were observing killer whales.

Less than an hour after arrival, the shark surfaced, and researchers, tourists and others on board witnessed Starbord grab the shark by the left pectoral fin and “pushing the shark forward several times before ultimately gutting it.” ” in less than two minutes, says the study.

A male killer whale was later photographed from one of the vessels with a “bloody, peach-colored piece of liver in his mouth,” the study said. Starboard’s male companion, Port, was spotted approximately 100 meters from the kill site and did not take part in the attack on the shark.

The pair are well known among the study’s authors and have been hunting and killing great white sharks for many years.

The two travel vast distances along the east coast of South Africa all the way to Namibia. Researchers suspect they first began hunting great white sharks in 2015. It wasn’t until 2022 that aerial photography captured killer whales killing a great white shark for the first time, says Alison Towner.

“Although we don’t have conclusive evidence of specific factors, the emergence of a pair of killer whales may be linked to broader changes in the ecosystem,” Towner says. “It is clear that human activities such as climate change and industrial fishing are having a negative impact on our oceans. More research and funding are needed to fully understand these dynamics. There are still many unanswered questions about these shark-hunting killer whales and where they came from.”

Killer whales are driving away great white shark populations, but researchers don’t know where the sharks are moving. “As they move, they may end up intersecting with intensive commercial fisheries,” Towner adds.

The distinct smell of shark liver in the air and seagulls diving towards a spot on the water’s surface, as well as a second 3.55 meter shark carcass found nearby, led onlookers to speculate that another great white shark may have been killed before the boats arrived at that time. day, the researchers said.

According to the study, the killing of a lone orca may have been possible due to the victim’s smaller size than a juvenile great white whale. Adult great white whales have a maximum length of 6.5 meters and a mass of 2.5 tons.

The swiftness of the attack may reflect Starboard’s skill and efficiency as a predator, which may be a response to the stress of spending time hunting near coastlines in areas where there are many people, the study suggested.

“We can’t assume that this killer whale has become more sophisticated, but the short period of time in which he killed the shark does demonstrate incredible skill,” Towner said.

Great white sharks’ livers are huge organs that make up about a third of their body mass and are rich in lipids, and killer whales discard the rest of the carcass – a selective feeding behavior known among other carnivores such as fur seals, brown bears and wolves, study says .

“The sightings reported here add to the fascinating story of these two killer whales and their capabilities,” Dr. Simon Elwen, founding director and chief scientist of Sea Search Research & Conservation and a researcher at Stellenbosch University in South Africa, said in a statement. “As intelligent predators, killer whales can quickly learn new hunting techniques on their own or from others, so monitoring and understanding the behaviors used here and by other killer whales in South Africa is an important part of helping us learn more about these animals.”