Killer whales have been feasting on the livers of great white sharks off the coast of South Africa, killing the vulnerable marine species. Marine Dynamics

Killer whales may have slaughtered at least four sharks in South Africa over the last couple of months, cutting out their livers as if they had the training of a surgeon. The Great White sharks have washed up after the killer whales feasted on their organs.

According to The Times, a shark was just found dead at Pearly Beach in southwestern South Africa and authorities suspect a killer whale — also known as an orca — was behind it, as it had wounds consistent with such an attack. Three other dead sharks were previously found at another beach about 20 minutes away with such wounds: their enormous and nutritious livers removed with precision.

The latest victim was about 13.5 feet long, local shark cage diving company Marine Dynamics reported in a post on Facebook.

“He was missing his liver, his testes and stomach,” the group said. “The carcass may be a few days old but it seems relatively fresh and bled out massively.”

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The World Wildlife Fund lists the great white as a “vulnerable” species because its numbers are decreasing, as people catch it for its fins and teeth or hunt it for sport, and as it gets wrapped up in other fishing nets. The Great White is a somewhat mysterious creature because scientists don’t understand its behavior very well, but it is important to the marine ecosystem because it is at the top of the food chain.

Great white sharks can grow to between 4,000 and 7,000 pounds and between 16 and 20 feet long. The WWF says it has 300 teeth, but instead rips off huge chunks of its prey and swallows them whole rather than chewing.

For comparison, killer whales can grow to between 23 and 32 feet long and weigh up to 12,000 pounds, making them also the size of a school bus.

South Africa protects great white sharks, but there have been fewer sightings of the swimmers in the southwestern part of the country this year, according to The Times, which could be because of what orcas are doing to them out in the water.

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The Dyer Island Conservation Trust has worked with Marine Dynamics to perform the autopsies. In the previous three cases, the sharks “had consistent bite wounds and were found to be missing their livers,” the trust explained in a blog post earlier this month. “This indicates what is known of orca predation on sharks, as they attack and stun the shark into tonic immobility and the buoyant liver rises to the surface through the injury.”

One of those sharks was also missing its heart.

According to the trust, there have been more killer whales in the area in the last couple of years and this gives biologists a better idea of how they affect sharks.