A pair of orcas near South Africa have developed a taste for great white shark livers, and have learned to kill the giant fish, remove its liver with "surgical" precision, and leave the rest of the carcass. Link to the Phys.org article here.
Scores of disemboweled sharks have been washing up on South African beaches.
""The dead sharks are torn open at the pelvic girdle, they have Orca teeth marks known as rake marks on their pectoral fins and their liver is missing," said Alison Towner, 37, a shark scientist with the Dyer Island Conservation Trust."
Video of the two orcas killing a white shark and then eating its liver:
As with the population of orcas off the Iberian coast in Europe who have taught each other to attack and capsize boats, this seems to be a new development in the culture of this African population, and biologists are worried that this liver-hunting practice is spreading.
Orcas are one of the few animals capable of developing localized cultural practices, with the capacity to invent and teach hunting techniques, which are then passed down to subsequent generations. Different local populations have developed their own favored hunting techniques such as:
- packs of orcas making waves to knock seals off of floating ice;
- jumping onto beaches to catch seal pups and, once caught, flinging the pup high into the air;
- herding herring into tight clusters and then stunning them from below with bubbles;
- and chasing bluefin tuna for sustained periods, pushing them beyond their aerobic limit (endurance-exhaustion hunting technique)
Video of the population that intentionally beach themselves to catch seals, and then seemingly play with their prey before killing: