Off the southern coast of South Africa, the ocean’s most feared predator has become prey. A pair of killer whales has developed a specialized and startlingly precise way of hunting great white sharks, and they are not after the whole animal. They open the shark, extract its enormous oil-rich liver, and leave much of the rest of the carcass to wash ashore, a pattern that has upended the local balance of power in the water.
Port and Starboard and the liver-only kills
The two orcas at the center of the story are well known to South African researchers, nicknamed Port and Starboard for their collapsed dorsal fins, which flop to the left and right. Beginning in 2017, great white carcasses started appearing on beaches around Gansbaai, in the Western Cape, with a grisly signature: their livers had been surgically removed, and in some cases the heart was gone too, while the rest of the body was largely intact.
The precision is what unnerves scientists. A study published in the African Journal of Marine Science documented five white shark carcasses in the Gansbaai area over a few months in 2017, most of them missing their livers, and linked the deaths to the presence of the killer whale pair. Rather than a frenzied attack, the killings look like practiced butchery, with the orcas apparently working through the pectoral area to draw out the liver in one piece. That level of technique suggests learned, refined behavior rather than opportunistic scavenging, and the two whales seem to have honed it into a repeatable method.
Why the liver is the prize
Targeting the liver is not random. A great white’s liver is enormous, in some cases amounting to a substantial fraction of the animal’s body weight, and it is packed with oils, including a compound called squalene that helps the shark stay buoyant. That makes the organ extraordinarily energy-dense, effectively the richest single meal a predator could extract from the shark’s body. For a large, calorie-hungry animal like an orca, stripping out the liver and leaving the leaner tissue behind is an efficient trade, maximizing energy gained for effort spent.
This selective feeding mirrors behavior seen in orca populations elsewhere that prey on other shark species and even on the tongues or livers of large whales. The animals appear to recognize which organ delivers the most nutritional payoff and to focus their formidable strength and coordination on obtaining it, discarding the parts that offer less reward.
Great whites fled an entire stretch of coast
The consequences reached far beyond the individual sharks that were killed. Great whites, sensing a lethal new threat, largely abandoned waters where they had reliably gathered for years. Tagging data and years of sightings records showed the sharks departing Gansbaai and staying away, with their numbers depressed for roughly two and a half years after the killings began. Scientific analysis by South Africa’s national parks service framed the shift as a reordering of the predator seascape, in which fear of the orcas reshaped where an apex predator was willing to live.
That absence rippled through the ecosystem. With great whites gone, other predators moved into the vacancy, including bronze whaler sharks, altering the mix of species and the pressures on the animals further down the food web. Detailed field observations, including a peer-reviewed account of orcas preying on white sharks and triggering a flight response, gave researchers direct evidence that the sharks were fleeing a genuine predator rather than leaving for unrelated reasons.
A single orca kills a great white in under two minutes
The behavior has continued to evolve in ways that surprise even the specialists tracking it. In June 2023, near Mossel Bay, one of the pair, Starboard, was documented killing a juvenile great white roughly eight feet long entirely on its own, dispatching the shark and removing its liver in under two minutes. As described in research reported through a scientific news release, it was the first time a lone orca had been seen taking down a great white without the coordinated help of a partner, a feat previously assumed to require teamwork.
After that solo kill, white sharks again vanished from the area for several months before trickling back in reduced numbers, reinforcing how quickly these predators respond to danger. The story of Port and Starboard has become a live case study in how a novel hunting strategy, once learned, can spread its effects across an entire marine community. It also complicates the popular image of the great white as an untouchable ruler of the sea, replacing it with a more layered reality in which even the ocean’s iconic hunter can be outmatched, hunted, and reduced to a source of a single prized organ.
This article was produced with AI assistance and reviewed by the Morning Overview editorial team.
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