The animals worked together to catch and strike the giant sharp-tailed sunfish. (Photo: Live Science)
Killer whales have been filmed using a hunting technique that scientists say has never been recorded before. Researchers observed the marine predators working together to grab a giant sunfish and strike it with extreme force, shattering its body into thousands of tiny pieces.This behavior was observed twice in the Gulf of California, more than a year apart. Researchers believe this technique may help young killer whales feed more easily. They also say it’s possible the animals were playing with their food, something that’s already known about killer whales. The results were published in the journal Frontiers in Ethology.The sunfish is among the heaviest bony fish in the world. They can reach more than 3 meters in length and weigh up to 2,000 kilograms.
They often come to the surface of the sea to rest, regulate their body temperature, or allow other animals to remove parasites from their skin. On the surface, they become easier targets for predators like killer whales.
Prey processing
The researchers studied two separate sharptail sunfish fishing events. During the first event, in July 2024, scientist Dr. Katherine Ayres observed a pod of killer whales that included a young animal.
The group had already killed a sharp-tailed sunfish.The female orca grabbed the dead fish by her large tail fin while the male orca swam towards her at high speed. Just before the male reached the fish, the female left the fish. The impact tore the sunfish’s body into thousands of small pieces that spread across the water.Young killer whales then feed on the smaller parts, while adult killer whales eat the larger parts of the carcass.In September 2025, wildlife photographer Hector Franz photographed another group of killer whales displaying the same behavior.
The researchers said the two events followed the same pattern, with one killer whale grabbing the fish while another struck it.
Why do killer whales do this?
The sunfish was already dead before it hit, the researchers said. This suggests that this behavior was not used to kill the fish, but rather to break it into smaller pieces.“We documented how one killer whale grabbed a sunfish and released it before other whales collided with it at high speed, causing the tissue to disintegrate into thousands of pieces,” Dr. Ayres said, Science X reported.“We think this may help young killer whales feed more easily or it may also be just for fun. Killer whales are known for playing with their food.”The behavior appears to be carefully coordinated, the researchers said. One orca held the carcass still while the other hit it with enough force to tear it apart.They also noted that killer whales had previously been seen sharing food with calves and younger members of their group. “Killer whales often tear apart their prey and share it with other members of the group, including calves and juveniles,” Ayres said.
Scientists say more research is needed
The team also pointed out another possible effect of breaking the fish apart. Sunfish have a jelly-like outer layer and skin that contains many microorganisms. When tissues break down, these microorganisms spread into the surrounding water. This may allow microbes in sunfish and orcas to come into contact, the researchers said, although the potential benefits of this are not yet clear.Until now, this behavior has only been observed with sharp-tailed sunfish.
The researchers said it is not known whether other species of sunfish would disintegrate in the same way.It is also unclear whether the same killer whales were involved in both events. The team said more high-quality images and videos would help identify individual animals and determine how common this behavior is.“Collecting good identification images whenever possible is key,” Ayres said. “We continue to see new techniques for how killer whales hunt and process their prey.”“It is one of the most famous marine predators in the world, but it continues to surprise us,” she added.