Killer whales execute skilled hunting techniques to bring juvenile great white sharks to the water’s surface.
Marco Villegas
Killer whales in the Gulf of California have adopted a sophisticated hunting method to target juvenile great white sharks: they turn them upside down to immobilize them. This finding implies there may be a previously unnoticed pod of orcas in the area that specialize in hunting sharks.
Only a limited number of killer whale populations are documented to consume sharks, and even fewer have been observed preying on great white sharks (carcharodon carcharius). Historically, killer whales (Orcinus orca) off the coast of San Francisco have been linked to a recorded incident involving a great white shark in 1997, and a carcass recovered near Australia revealed signs of an orca attack, documented in 2023. Until recently, only one instance of a killer whale preying on a young great white shark had been noted, and that was in South Africa.
Jesus Eric Higuera-Rivas, an independent marine biologist from Mexico, along with colleagues, captured video footage of killer whales hunting juvenile great white sharks on two occasions in the Gulf of California. The initial footage, taken in August 2020, depicted five female killer whales collaboratively pushing a juvenile great white to the surface. “The killer whale was attempting to ram the great white and flip it over,” Higuera-Rivas remarked.
This tactic induced a temporary state of paralysis in the shark, known as tonic immobility. The orcas also managed to consume the energy-rich liver of the shark, sharing it among themselves. Shortly thereafter, the pod repeated their attack on another young great white shark. In August 2022, another group of five killer whales exhibited the same hunting strategy against juvenile great whites in the identical location.
Some of the killer whales involved in the first incident were identified as those previously seen hunting whale sharks and bull sharks. However, the video from the second incident was insufficiently clear to confirm if those were the same orcas. “But it’s highly probable,” says Higuera-Rivas.
The hunting behaviors of killer whale populations differ significantly based on their habitat. “Orcas are like hunting machines, akin to snipers. They employ specific strategies tailored to their prey,” Higuera-Rivas explains. These observations indicate that the killer whales in question may be part of an unrecognized group of shark hunters.
“This provides another example of a distinct feeding strategy, likely not shared by other orca groups globally,” states Andrew Trites from the University of British Columbia, Canada. However, further research is necessary for conclusive evidence, as these killer whales might descend from Pacific Northwest populations that hunt different shark species.
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Source: www.newscientist.com
