Orcas Killing Great White Sharks: Startling New Behavior Revealed
In a shocking turn of events, a pair of orcas has been working together to hunt and kill great white sharks along the South African coastline since 2017. This hunting approach has not only driven the sharks away from certain areas but has also raised questions about its implications for the wider marine ecosystem. Recent research has shed light on this behavior, offering valuable insights into the predatory habits of these apex predators.
The researchers were able to witness one of the orcas, a male named Starboard, single-handedly kill a 2.5-meter juvenile white shark in just two minutes. Dr. Primo Micarelli, a marine biologist at Italy’s Sharks Studies Centre and the University of Siena, who was present during the attack, expressed his awe at the sight of Starboard carrying the shark’s liver past their vessel. However, he also voiced concerns about the potential impact on the coastal marine ecology balance.
While it is not uncommon for orcas to hunt large animals individually, this is the first documented occurrence involving great white sharks. Typically, orcas engage in cooperative hunting behaviors, surrounding their prey and using their combined intelligence and strength to attack. However, Starboard’s solitary kill challenges this conventional understanding of orca hunting behavior.
Lead author Alison Towner, a doctoral researcher at Rhodes University, explains that previous observed attacks on great whites involved two to six orcas and took up to two hours. The swift and efficient nature of Starboard’s attack suggests a level of skill and proficiency that may be a response to the stress of hunting near shorelines where humans are abundant.
The event detailed in the study took place on June 18, 2023, near Seal Island close to Mossel Bay. Witnesses on two vessels observed Starboard gripping the left pectoral fin of a shark and eviscerating it within two minutes. Photographs later captured Starboard with a bloody piece of liver in its mouth, while its companion, Port, remained at a distance during the kill.
The duo, known for their distinctive bent dorsal fins that inspired their names, has been hunting and killing great white sharks for several years. They travel long distances along South Africa’s eastern coastline, raising questions about their origins and motivations. Researchers suspect that broader changes in the ecosystem may have triggered their arrival. Human activities, such as climate change and industrial fishing, are known to stress the oceans, and understanding these dynamics requires further research and funding.
The killing of great white sharks by orcas has had a significant impact on their populations, causing them to relocate. However, researchers are uncertain where these sharks are moving to and whether they may overlap with heavy commercial fisheries. The distinct smell of shark liver in the air and the discovery of a second shark carcass nearby indicate that more killings may have occurred before the researchers’ arrival.
The livers of great whites are large organs, comprising about a third of their body mass and rich in lipids. The orcas selectively feed on these nutrient-rich livers and discard the rest of the carcass—a behavior observed in other carnivores such as harbor seals, brown bears, and wolves.
Dr. Simon Elwen, founding director and principal scientist at Sea Search Research & Conservation, emphasizes the importance of monitoring and understanding the behaviors of these killer whales. As intelligent top predators, orcas can rapidly learn new hunting techniques on their own or from others. Studying their behaviors in South Africa is crucial for gaining insights into these remarkable animals.
The hunting strategy employed by these orcas has not only captivated scientists but also raised concerns about the delicate balance of the marine ecosystem. As researchers continue to unravel the mysteries surrounding these shark-hunting killer whales, it becomes increasingly clear that further investigation and funding are necessary to protect our oceans and the diverse species that inhabit them.
