Killer whale vs shark: Solo orca eats great white

Scientists said it was "unprecedented" and showed the exceptional predatory skills of killer whales.

Two orcas in particular off South Africa's coast have been observed before working together to hunt and kill sharks, including great whites.

"But this caught us off guard," said shark biologist Dr Alison Towner.

Dr Towner, who is from Rhodes University in Grahamstown, South Africa, has studied the animals for several years. She and her colleagues published a detailed and grisly account of their new observations in the African Journal of Marine Science.

The attack - filmed in 2023, which you can watch here - was, scientists, said "solo and swift". The male killer whale killed the shark and consumed its liver - all in under two minutes.

Scientists first captured drone footage of two male orcas working together to hunt great white sharks in 2022.

The scientists then reported that the animals, nicknamed Port and Starboard because their dorsal fins are bent in opposite directions, "exhibited a predilection for extracting and consuming the sharks' livers".

During the attacks, the sharks would tightly circle the killer whales, in a desperate attempt to avoid predation," recalled Dr Towner.

In this newly reported attack, Starboard hunted on his own. Scientists described how the orca gripped the left pectoral fin of a 2.5m long juvenile shark and "thrust forward several times before eventually eviscerating it".

Marine mammal scientist Dr Luke Rendell from the University of St Andrews said it "a really beautiful observation" of the behaviour.

"It's interesting that it's just one animal," he told BBC News, and how much skill it demonstrates in tackling the shark - ramming it in the side and grabbing the pectoral fin to keep away from those big, nasty jaws.

"A great white shark is a nice, big concentration of food, so it's perhaps unsurprising that some populations [of orcas], where these sharks occur in sufficient numbers, have learned to exploit that."

The solitary orca (seen on the right of the image) 'eviscerated' the shark in under two minutes

It raises questions about how killer whale behaviour might be affecting the shark populations in the areas.

The scientists do not know what is driving the behaviour, but Dr Towner told BBC News that it was becoming evident that "human activities, like climate change and industrial fishing, are exerting significant pressures on our oceans".

And there could be health repercussions for killer whales hunting sharks, including ingesting toxins and metals from shark flesh.

"Disruptions in the balance of apex predators can affect other species too," explained Dr Towner. "Endangered African penguins could face increased predation by cape fur seals [if the fur seals are not being eaten by] white sharks."

Dr Rendell pointed out that there was no way of knowing if the behaviour was new or simply observed for the first time. "But what really stands out is is how skilful these animals are as hunters."

Dr Towner added that every discovery in these interactions [between orcas and sharks] was "fascinating".

-bbc