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Insights into the hunting behaviour of orcas
Orcas normally hunt in packs. Researchers in South Africa have now been able to document for the first time how a single killer whale killed a great white shark.
Off the coast of South Africa, a team of marine biologists and researchers has observed for the first time how a single orca killed a great white shark. The attack happened very quickly and the kill took place within just two minutes. An impressive spectacle, one of the largest and fastest predators in the world was killed by another predator.
The event is an indication that orcas do not have to hunt in packs to take down great white sharks, which are among the largest predators in the world. Marine biologist Alison Towner from South Africa's Rhodes University, who led the international team, spoke of "incredibly interesting insights" into the hunting behaviour of orcas.
Orcas normally work in groups to hunt and kill great white sharks as well as other large prey. These include sea lions, seals, other shark species and sometimes even whales. Orcas can also hunt most of these prey alone. However, no single orca has ever been observed hunting a great white shark, whose fatty liver is a delicacy for them.
In June 2023, the scientists observed for the first time how an orca hunted a two-and-a-half metre 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, which calls into question the conventional cooperative hunting behaviour known in the region," said Towner. The researcher and her team present their observations in the "African Journal of Marine Science".
Although a second orca was nearby, it did not participate in the hunt, according to the publication. The next day, the carcass of another great white shark was found, which had also been killed by killer whales.
Shark hunting by orcas changes entire marine ecosystem
At the end of June 2022, a long-term study by marine biologist Alison Towner was published in the African Journal of Marine Science, showing that great white sharks avoid the coastal area around Gansbaai (South Africa) because of a pair of orcas. However, this region was considered a legendary area for observing the predatory fish.
During the course of the study, a total of eight great white sharks fell victim to an orca attack. Seven of them were washed ashore without their livers and hearts - wounds that could only have come from the pair of whales. Experts assume that the number of fatalities is much higher, as not all sharks are only "half" eaten.
The results of this five-year study indicate that the attacks triggered a rapid and long-term mass displacement of great white sharks. Sightings of great white sharks have "dramatically decreased" in the region since the orca attacks began.
"The absence of sharks is a completely different parameter for the region and the marine ecosystem is changing as a result," Towner predicted back in 2022. Fewer great white sharks, for example, would lead to a larger number of Cape fur seals. This would have a negative impact on the endangered African penguins, which in turn are hunted by the seals.
Killer Whale attacks White Shark (youTube)
https://www.youtube.com/watch?v=o4UCFJZauAM