Orcas Feast on Livers of 17 Sharks in Biggest Killing Spree to Date

Orcas have feasted on the livers of 17 sharks in South Africa, in their biggest single killing spree to date.

The two adult male orcas responsible, known to scientists as Port and Starboard, are notorious for attacking and eating sharks off the South African coast.

Scientists with boat tour agency MarineDynamicsAcademy saw the two orcas repeatedly diving down in one spot of ocean for almost two hours near Pearly Beach, Gansbaai in the Western Cape, before they left for deeper waters.

Orca killing sharks
A photo shows the two orcas in the spot off the Western Cape coast where they feasted on 17 sharks. The pair are known to scientists as Port and Starboard. Marine Dynamics

Just a few days later, 11 broadnose sevengill shark carcasses were found washed ashore on the same beach. In total, 17 sharks were confirmed dead.

The orcas are easily recognizable due to their collapsed dorsal fins. Photographs show the marine mammals swimming in the spot where they massacred the sharks.

Alison Towner is a PhD candidate at Rhodes University in the Eastern Cape Province of South Africa. She leads research on killer whales preying on sharks in Gansbaai and she helped perform necropsies on the sharks.

Every sevengill shark was "torn open and missing its liver," Towner said in a statement.

The sharks were all females measuring between 5 and 7 feet. They all had similar injuries to sharks found killed in False Bay—an area in the extreme south-west of South Africa where the orcas have been devouring great white sharks.

Shark killed by orca
A photo shows one shark out of the 17 killed by orcas. The shark has had its liver torn out. Marine Dynamics

This is the largest amount of sharks these orcas have devoured in one instance, Towner said. There could even be more shark carcasses that did not wash ashore.

The notorious pair of killer whales gained attention in 2015. It became clear that Port and Starboard were responsible for the deaths of several broadnose sevengill sharks that were discovered in a similar area by scuba divers.

However, the pair did not stop here. Between 2017 and 2019, the orcas started turning their sights on great white sharks.

In a study published in the African Journal of Marine Science, researchers recorded that since 2017, eight great white shark carcasses washed up on beaches near Gansbaai. Seven of those had their livers removed, with some even missing their hearts.

There was no question that the wounds on the carcasses were caused by orcas.

Towner had told Newsweek: "There were killer whale tooth impressions on the pectoral fins of the sharks, [and] their livers were removed so neatly—it would take coordination of large and sophisticated animals to tear a white shark open and do this.

"Also each time a dead shark washed out, there had been sightings of killer whales in the area, so all the evidence pointed to killer-whale predation, and was also confirmed by killer-whale biologists."

Gansbaai, which is located around 60 miles southeast of Cape Town, was once a great white hotspot. There are many cage-diving attractions operating in the area, because of the high number of sharks.

However, since the orcas came to the region, great white sharks began leaving, possibly to avoid the same fate as others.

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