The image is as striking as it is unprecedented: one orca firmly grasps the tail of a sunfish while another dives at full speed toward it. The impact is so brutal that the enormous fish's body explodes into thousands of fragments that float in the water. What appears to be an extreme hunting scene is, in reality, a behavior that scientists had never before documented in these cetaceans and which has just been published in the journal Frontiers in Ethology.
The discovery, led by researcher Kathryn Ayres of the organization Beneath The Waves, is based on two separate recordings made in the Gulf of California, off the coast of Mexico. In both, a group of killer whales (Orcinus orca) executes a coordinated maneuver: an adult female grabs a sharp-tailed sunfish (Masturus lanceolatus) by its large tail fin, while a male accelerates and rams it just after the female releases it. The result is the almost instantaneous disintegration of the animal, which can reach 2.000 kilograms in weight and three meters in length.
A hunting technique never seen before
The first incident occurred on July 29, 2024, when Ayres was diving as a marine safari guide near San José del Cabo, in Baja California Sur. A group of three females, one male, and a juvenile had just finished hunting a manta ray when the carcass of a sunfish appeared. The female held it, the male lunged, and the juvenile pounced to devour the small fragments while the adults consumed the main body. The second incident, recorded on September 7, 2025, by tour operator Héctor Franz, repeated the exact same sequence in the channel off Cerralvo Island.
The researchers emphasize that in both cases the ocean sunfish was already dead and its internal organs had been removed, ruling out the possibility that the ramming was a method of killing. "We believe this could help younger orcas, with their smaller jaws, to feed more easily, or it could simply be for fun. Orcas are known for playing with their food," Ayres explained in a statement.
The study's co-author, marine biologist Erick Higuera , executive director of Orcas Mexico, adds that the maneuver demonstrates a capacity for tactical planning: "Orcas are able to mentally devise a multi-step plan and execute it with military precision." Higuera also points out that the ocean sunfish's body structure, with a thick layer of gelatinous collagen composed of almost 90% water, makes it especially vulnerable to fragmentation from kinetic impact.
Game or food strategy?
The scientific community does not rule out that the behavior has a playful component. Orcas are known to play with objects and dead prey: in Puget Sound, off the coast of Washington, they have been seen using dead salmon as hats, and in other regions they toss sea lion skins into the air. "In many cases, there doesn't seem to be a functional reason beyond play," says Monika Wieland Shields, director of the Orca Behavior Institute, who was not involved in the study.
However, the presence of a juvenile in the first event, which actively fed on the smallest fragments, suggests parental investment . "Breaking a hard, rubbery sunfish into small pieces makes it much more accessible to a young orca," explains Higuera. The adults did not consume the tiny fragments, leaving them for the calf, which reinforces the hypothesis that the technique serves to facilitate feeding for the younger individuals.
The study also draws a parallel with another recent behavior observed in orcas: attacks on sailboat rudders off the coast of the Iberian Peninsula. "There is a clear conceptual link," says Higuera. "In both cases, we observe cognitive and self-rewarding behaviors that spread through social learning. The difference lies in the objective: while Iberian orcas have developed a game centered on rudders, those in the Gulf of California apply this playful innovation to food processing."
The researchers emphasize the need for more high-quality recordings, especially of dorsal fins and eyespots, to identify individuals and determine if this technique is passed down through generations. “We continue to uncover new techniques about how orcas hunt and process their prey,” Ayres concludes. “They are one of the world’s most iconic marine predators, and yet they never cease to amaze us.”
This behavior, which combines coordination, brute force, and possibly play, opens a new window into the intelligence and culture of orcas. While scientists continue to gather data, images of these cetaceans taking down a two-ton sunfish have already gone viral, reminding us that the ocean still holds secrets that defy our imagination.