Orca Stuns Researchers as It Single Handedly Hunts and Kills Great White Shark

CREDIT: Christiaan Stopforth (Drone Fanatics SA) and Arianna Di Bari (Shark Studies Center Scientific Institute).

Sometimes, when they’re not busy attacking boats or porpoises or keeping an eye on their grown-up sons, certain pods of orca whales also engage in intense battles with the formidable great white shark. These groups of marine mammals are known for their ability to hunt and kill these massive fish, showcasing a clash between two top predators. However, a remarkable discovery has now been made as a lone orca, also known as a killer whale, has been observed devouring a great white shark for the very first time. The extraordinary event took place off the coast of Mossel Bay, South Africa, and the findings detailing this unprecedented behavior have been published in the African Journal of Marine Science. Alison Towner, a shark biologist from Rhodes University in South Africa and co-author of the study, expressed amazement at this astonishing predation, highlighting the exceptional skills of the killer whale.

Usually, orcas, also known as killer whales, work together in groups to capture their prey, which can include sea lions, seals, sharks, and even other whales. When hunting as a pod, they surround their target and utilize their collective strength and intelligence to launch an attack. On the other hand, South Africa’s white sharks are formidable predators in their own right, renowned for their impressive acrobatics and solitary hunting techniques.

In 2022, the same team of researchers made a notable discovery. They found that a pair of orcas named Port and Starboard had been actively hunting and killing South Africa’s white sharks since 2017. This predatory behavior has caused a significant decline in the number of sharks frequenting their usual gathering areas. While orcas are capable of hunting large prey individually, the recent observation of a lone whale attacking a great white shark marks the first documented instance of such an occurrence.

The smell of oil extracted from shark livers

This incident took place in June 2023 near Seal Island in Mossel Bay, which is about 248 miles east of Cape Town. It challenges the common beliefs about cooperative hunting behaviors in the region. A lone orca named Starboard was observed working alone to quickly incapacitate and consume an eight-foot-long young white shark in just two minutes. Later, the orca was seen carrying the shark’s liver in its mouth.

Esther Jacobs, representing the marine conservation initiative Keep Fin Alive, described the day’s events. Upon reaching Mossel Bay’s Seal Island, they noticed the scent of shark liver oil and an observable film on the water surface, indicating a recent kill. While tracking Port and Starboard near the island, they noticed the orcas staying separate. Initially, seeing the fin of a white shark breaking the surface sparked excitement, but it quickly turned into a somber realization as Starboard swiftly approached. Witnessing Starboard swiftly prey on her favorite shark species was both devastating and incredibly powerful, according to Jacobs.

What Jacobs and others on the water witnessed that day is a specialized feeding behavior. Orcas in South Africa seem to have a strong preference for consuming the liver, which is rich in fats, from white sharks.

“I have been visiting South Africa for more than twenty years, and I have witnessed the significant influence these killer whales have on the local white shark population,” said Primo Micarelli, who is from the Shark Studies Centre and Siena University in Italy. “The sight of Starboard carrying a white shark’s liver past our boat is something I will never forget.”

A timeline of an orca whale preying on a white shark. CREDIT: Christiaan Stopforth (Drone Fanatics SA) and Arianna Di Bari (Shark Studies Center Scientific Institute).

During these encounters, at least two great white sharks were killed. Another shark measuring 11.6 feet in length was found nearby.

“This observation provides evidence of a killer whale hunting alone, which challenges the usual cooperative hunting behaviors seen in this region,” said Towner.

Changes in the way things work in the ocean

Not only does this research provide new insights into how orcas hunt, but it also sheds light on the changes that occur in the ecosystem when orcas replace sharks as the top predator. Understanding these dynamics is crucial for developing conservation strategies that can adapt to environmental and ecosystem shifts.

Ecologist Simon Elwen expressed his thoughts on the observations, highlighting the fascinating abilities of killer whales as intelligent predators. He emphasized the importance of monitoring and understanding the behaviors of killer whales in South Africa to gain more knowledge about these remarkable animals.

Although Elwen is not directly involved in this study, he is an expert in whale ecology at the University of Stellenbosch and plays a significant role in whale research and conservation.

These new findings, along with future studies, will provide scientists in the region with valuable insights to inform conservation measures. According to Towner, experienced “shark spotters” in Cape Town recorded more than 300 sightings of great white sharks across eight beaches in 2011. However, since 2019, there have been no sightings in the area, indicating that the sharks have moved farther away from Cape Town. The presence of orcas like Port and Starboard, combined with limited resources, has driven these great white sharks to seek new habitats.

Micarelli expressed his growing concern about the balance of coastal marine ecology, despite acknowledging his awe for these predators.