“Proof of high intelligence”
This makes the great white shark an easy victim for the orcas: “In this temporary state, the shark is defenseless, so the orcas can remove its nutrient-rich liver and probably eat other organs before leaving the rest of the carcass behind,” explains Rivas. The whales bit open the shark’s belly and ate its liver. The second orca hunt observed by the biologists was very similar: five orcas pushed a young white shark to the surface of the water and turned it onto its back. They then killed him and ate his liver.
According to biologists, this behavior suggests that this group of orcas has learned to exploit the freeze reflex of great white sharks. “This behavior is evidence of the orcas’ high intelligence, strategic thinking and strong social behavior, as hunting techniques are passed down within groups over generations,” says Rivas.
Targeted hunting of inexperienced young sharks
Also clever: the orcas in the Moctezuma group apparently only attack young, inexperienced white sharks. “This is the first time we have observed orcas repeatedly targeting young white sharks,” says co-author Salvador Jorgensen from California State University. The killer whales may have learned that juveniles are easier prey than adult great white sharks.
“Adult white sharks react quickly to hunting orcas: They then leave their seasonal gathering areas completely and do not return for months,” says Jorgensen. “But these young white sharks could still be naive towards the orcas. We don’t yet know whether the white sharks instinctively flee when attacked or whether this escape reaction has to be learned first.”
No exception?
The new observations demonstrate how capable the predatory killer whales are of learning and how well orcas can adapt to the behavior of their prey. At the same time, they prove that hunting great white sharks is not just a peculiarity of a few South African orcas: “I believe that orcas anywhere could catch a great white shark if they wanted to,” says Rivas. White sharks could therefore be on the diet of orcas elsewhere more often than previously assumed.
The biologists now want to continue observing the Californian orcas and find out whether they regularly hunt white sharks or only when young are available. (Frontiers in Marine Science, 2025; doi: 10.3389/fmars.2025.1667683)
Quelle: Frontiers
November 3, 2025 – Nadja Podbregar