An infamous pair of adult male orca whales in South Africa killed 17 sharks in "one sitting," according to marine biologists.

The team at Marine Dynamics Conservation Trust has been tracking the two whales, named Port and Starboard, who are known to prey on several species of sharks.

They found the orcas "repeatedly diving down in a small area for almost two hours before they departed offshore."

Days later, they found the remains of 11 of the 17 killed sevengill sharks in Pearly Beach. Sevengill sharks can grow up to 10 feet in length.

"Each sevengill shark was torn open and missing its liver," said the Maine Dynamics Conservation Trust. The orcas had also devoured the contents of the sharks' stomachs.

The conservation trust said the sharks were washed to shore as due to storm and surge conditions, Alison Towner, PhD candidate at Rhodes University and research lead, said, "this is the largest amount of sharks these orcas have killed in this area in one sitting," says Towner, "There could well be more that didn't wash out."

The orca duo have been tracked since 2009 but are most commonly seen in False Bay, South Africa, where they were first spotted in 2015.

They are easy to identify due to their rare collapsed dorsal fins.

Before 2015, great white shark sightings were common in the region and were famous for spectacular breaching when they hunted seals, but their population is now negligible.

The carcasses of several great white sharks have since washed up on the shores of False Bay, all grossly injured and with their oil-rich livers ripped out. For the first time in May 2022, scientists were able to film Starboard killing a great white shark.

This article was originally published by Business Insider.

More from Business Insider: