A team of researchers off South Africa has observed for the first time how a single orca killed a great white shark in just two minutes. It demonstrated that orcas do not have to hunt in packs to kill great white sharks, which are among the world’s largest predators.
Marine biologist Alison Towner from South Africa’s Rhodes University, who led the international team, spoke of “groundbreaking insights” into the hunting behavior of orcas.
Hunting in groups
Orcas, also known as killer whales or killer whales, usually work in groups to hunt and kill great white sharks and other large prey. These include sea lions, seals, other shark species and sometimes even whales. Orcas can also hunt most of these prey on their own. However, no single orca has ever been observed hunting a great white shark, whose fatty liver is a delicacy for them.
In June 2023, scientists observed for the first time how an orca hunted a two and a half meter long young great white shark off the coast of the small town of Mossel Bay in the Western Cape province and later swam past a boat with its liver in its mouth. “This sighting provided evidence of solo hunting by at least one killer whale, calling into question conventional cooperative hunting behavior known in the region,” Towner said. The researchers present their observations in the “African Journal of Marine Science”.
Orca pair systematically killed great white sharks
A team led by Towner had already discovered in 2022 that an orca pair was systematically killing white sharks in the coastal area of Gansbaai. This was considered one of the most legendary areas in the world for white shark sightings. The results of this five-year study suggest that the attacks triggered a rapid and long-term mass displacement of great white sharks. Sightings of great white sharks in the region have “decreased dramatically” as a result.
The absence of great white sharks is unprecedented for the region and is changing the marine ecosystem, Towner said in 2022. For example, fewer great white sharks led to greater numbers of Cape fur seals. This has a negative impact on the endangered African penguins, which are hunted by the seals.