Orcas discovered to play at exploding fish

BarcelonaLet the majesty of orcas not deceive you: they are intelligent, strategic, and relentless predators in the oceans. An investigation published in the scientific journal Frontiers in Ethology has recorded and documented for the first time a never-before-seen behavior in these cetaceans in the Gulf of California, Mexico. As can be seen in the images, the orcas coordinate to hold and ram a prey, throwing it into the air.

The study, led by Dr. Kathryn Ayres of the NGO Beneath The Waves, explains this strategy in detail: an adult orca holds a sharp-tailed sunfish (another marine giant that can weigh up to two tons) by its posterior fin. Just as a second orca swims at full speed towards the prey, the first one releases it, and with the impact, the fish's tissue disintegrates into thousands of fragments that remain floating in the water.

There are two independent records of this phenomenon, dating back to July 2024 and September 2025, and the conclusion reached by the experts is that it is not a killing technique, as the prey was already dead in both cases, but rather a method of processing food.

To feed the young or for fun?

The scientific community is studying three hypotheses to explain this unusual behavior of killer whales. The first points to a parental investment strategy: by making the sunfish "burst," adults fragment its carcass into smaller, easier-to-consume pieces so that the group's pups and juveniles can feed on the remains floating in the water. The second hypothesis is that it is simply a playful behavior, as killer whales have a very complex social life and often play with their prey before or after eating them.

Finally, researchers also propose a possible immune benefit: the sunfish is covered in a gelatinous layer with a very particular microbiome, and by dispersing these microorganisms in the water, killer whales could obtain some nutritional advantage or contribute to regulating their own immune system.

The research has also opened new questions about the victim. For now, this extreme fragmentation of the tissue has only been observed in the sharp-tailed sunfish species, suggesting that it could be a unique structural response of this animal to high-energy impacts.

The authors of the study emphasize the importance of continuing to collect high-quality images in the area to identify the killer whales by their dorsal fins and eye spots, and to find out if it is the same group of cetaceans. "They are one of the most iconic predators in the world, and yet they continue to surprise us," concludes Ayres.