Six-panel sequence of underwater video stills showing orcas ramming a sunfish: a female orca holds the tail of a large round sunfish in her mouth, a male orca accelerates toward it and collides headfirst, and the fish fragments into white pieces drifting through bright blue water. Video stills: K. Ayres, reproduced from Ayres et al., Frontiers in Ethology (2026), CC BY 4.0.
The sequence from the July 2024 encounter off San Jose del Cabo: an adult female orca holds a dead sharp-tail sunfish by its tail fin, an adult male accelerates toward it and rams it at high speed, and the fish bursts into fragments that drift through the water. Video stills by K. Ayres, reproduced from Ayres et al., Frontiers in Ethology (2026), CC BY 4.0.

In July 2024, off the coast of San Jose del Cabo at the southern tip of Baja California, a group of orcas finished eating a spine-tail devil ray, then turned to a second carcass: a dead sharp-tail sunfish, one of the heaviest bony fish in the ocean. What happened next had never been formally documented. An adult female orca gripped the sunfish by its tail fin and held it steady in the water. An adult male accelerated toward the fish, belly up, at high speed. The female let go just before impact. The male slammed headfirst into the sunfish with enough force that the body came apart into thousands of fragments, with an audible impact that carried through the water. A juvenile orca, roughly half to three-quarters the size of the adult female, swam in and began eating the smaller pieces, while the adults fed on the split-open body and left the scattered fragments behind.

Kathryn Ayres, a research scientist at the ocean-health nonprofit Beneath The Waves, filmed the encounter herself with a GoPro. Just over a year later, in September 2025, a second group of orcas in the Gulf of California performed the same sequence: one female stabilized a sunfish while a second orca rammed it at speed, producing the same burst of fragments, with a third adult joining in afterward. That footage was filmed by Héctor Franz with a DJI Osmo Action 5. Ayres and her colleagues, including marine biologist Erick Higuera Rivas of Conexiones Terramar, published both events on July 23, 2026 in Frontiers in Ethology, and gave the behavior a name: ram-to-fragment.

A fish built like a floating slab

The sharp-tail sunfish, Masturus lanceolatus, belongs to the family Molidae, the sunfishes, which are the largest bony fish on Earth. Adults can exceed three meters in length and weigh as much as 2,000 kilograms, roughly 4,400 pounds. Despite their size they are not built like typical predators. Molids mostly eat gelatinous plankton, and they spend much of their time near the surface, basking, regulating body temperature, and having parasites removed, habits that leave them exposed to hunters in open water.

Under the skin, a molid carries a thick, gelatinous collagen layer called the capsule, made of nearly 90 percent water. That structure may be part of why the ramming is so dramatic. The researchers note that this level of fragmentation has not been reported for other sunfish species, and they suggest sharp-tail sunfish tissue may respond to high-energy impacts in a distinctive way. The species also has a more pronounced clavus, the tail fin, than other molids, which the paper says may give orcas an effective grip point during the maneuver.

Orcas already had a playbook for sunfish

Orca-sunfish encounters are not new. A 2023 global review led by Ingrid Visser of the Orca Research Trust catalogued 73 interactions between 1961 and 2022, clustered in Oceania, the eastern Pacific off Central and North America, and the South Atlantic. That review also documented the previously known hunting strategy: orcas target the sunfish's pectoral fins, open a wound in its side, remove the intestines and other organs, and then insert their rostrum into the body cavity to extract tissue.

The Gulf of California is one of the hotspots. A 2025 study documented 21 orca-sunfish predation events involving 17 photo-identified individual orcas, and suggested that at least four distinct orca groups include sunfish in their diet. The new paper's contribution is the specific maneuver: the force of the impact, and the near-total disintegration of the prey, which had not been described before.

Working in tandem is itself established orca behavior in the region. In the Gulf of California, orcas have been documented cooperating to hunt whale sharks, with several individuals holding the shark steady while another rammed it. The authors draw a direct comparison: the stabilize-and-ram coordination in the sunfish events, they write, indicates a high degree of cooperative precision.

Six-panel sequence of darker underwater video stills showing a second orca ramming a sunfish in the Gulf of California in September 2025: a female orca stabilizes the sunfish, a second orca rams it, and the fish breaks into fragments with white tissue drifting through the water. Video stills: H. Franz, reproduced from Ayres et al., Frontiers in Ethology (2026), CC BY 4.0.
The September 2025 encounter off Isla Cerralvo, filmed by Héctor Franz, followed the same sequence: stabilize, ram, fragment. A third adult orca joined after the impact, and the calf present was documented extracting tissue from the carcass. Video stills: H. Franz, reproduced from Ayres et al., Frontiers in Ethology (2026), CC BY 4.0.

A feeding strategy, a game, or both

The team's interpretation is deliberately open. The most obvious reading is parental investment: shattering the carcass turns one enormous, awkward meal into bite-size pieces that a calf or juvenile can actually eat. In the first event, the juvenile fed on the small fragments while the adults ate the main body, which fits that picture. Orcas are known to tear prey apart and share it with younger members of the group.

The other reading is play. Orcas are famous for playing with their food, and they engage in non-consumptive interactions with prey, striking or killing animals without eating them. Higuera Rivas told NPR that the two events had the character of a social game, with one orca setting up the prey for another to hit. For a behavior to count as fun, he said, it needs to be voluntary, rewarding, and involve modified or exaggerated behaviors, and both encounters fit that description in his view.

Robert Pitman, a marine ecologist at Oregon State University who was not involved in the study, leans toward the feeding explanation. Sunfish are difficult prey, he told NPR: their skin is dense, rubbery, and collagenous, several inches thick, and "there just doesn't seem to be much to eat on a sunfish." Older orcas that hunt sharks can wear their teeth down to the gums, and young orcas may have no teeth at all. Ramming a sunfish into pieces, Pitman said, is "a clever way to deal with a difficult prey item."

Higuera Rivas came to a similar conclusion from a different angle. "Orcas do not possess hands or tools to tear apart their prey," he said, so ramming sunfish into "bite-size pieces" is "incredibly practical." His working view is that the behavior is a feeding-plus-fun social activity, and he wants more examples before committing. If scientists ever watched adults ram a sunfish with no young present and no one eating the shreds, he said, that would support the entertainment reading.

Four-panel underwater illustration of the ram-to-fragment sequence: an orca grips a sunfish by its tail, a second orca lines up and accelerates toward it, the ramming orca collides with the fish as fragments burst outward, and the sunfish floats in pieces while an orca swims nearby. Illustration: Impossible Universe Editorial Team (generated).
The ram-to-fragment sequence in four steps: hold, release, ram, fragment. The paper's authors stress that in both documented events, the sunfish was already dead when the ramming happened. The behavior appears to be prey processing, not a way of killing. Illustration: Impossible Universe Editorial Team (generated).

The fragments change the water

There is a quieter side effect. The sunfish's gelatinous capsule and outer skin host distinct microbial communities, and when the tissue shatters, those microbes disperse into the surrounding water, changing its nutrient composition. The paper suggests this redistribution may facilitate contact between the sunfish's microbiome and the orcas', which could carry nutritional or other functional benefits. It is a speculative thread, and the authors present it as such, but it is a reminder that a single high-speed collision can ripple through an ecosystem in ways that are easy to miss.

Two sightings, many open questions

Two events is a tiny sample. The researchers cannot say whether the same orcas were involved in both encounters, because the identification features, dorsal fins and eye patches, were not captured clearly enough in both. They cannot say whether ram-to-fragment is a local specialty or a widespread technique. Pitman noted that the behavior could be a regional innovation; Higuera Rivas said it may be "cultural knowledge" restricted to a handful of pods in the area. Whether orcas elsewhere in the world practice it remains to be seen.

There is also an observation-bias problem, which the paper flags itself. Tourism in the Gulf of California has grown, and affordable drones and underwater cameras have put capable recording gear in far more hands. Many orca-sunfish interactions have been documented through social media posts. More sightings may reflect more eyes on the water rather than more actual behavior. Mexican authorities, the authors note, recently released a management plan to regulate swimming with orcas in the Gulf of California, and the paper argues that managed collaboration between scientists and tour operators is one of the best ways to catch rare behaviors like this one on camera.

Map of the southern Baja California peninsula and the Gulf of California with two marked locations: Event 1 off San Jose del Cabo at the peninsula's southern tip, and Event 2 in the channel off Isla Cerralvo on the gulf side. Reproduced from Ayres et al., Frontiers in Ethology (2026), CC BY 4.0.
Where the two encounters happened. Event 1 took place off San Jose del Cabo in July 2024, and Event 2 in the channel off Isla Cerralvo in September 2025. Reproduced from Ayres et al., Frontiers in Ethology (2026), CC BY 4.0.

What would settle the question? More footage, especially with clear identification shots. "Collecting good identification photographs whenever possible is key: we are still seeing new techniques of how orcas hunt and process their prey," Ayres said. "They're one of the most iconic marine predators in the world, yet they continue to surprise us."

Pitman, who has seen orcas carrying sunfish "like a large pizza box in its mouth" many times without knowing what they were doing, put it more simply: "Maybe now I know."

Sources

Hero and inline figures: reproduced from Ayres et al., Frontiers in Ethology 5:1835536 (2026), an open-access article licensed under CC BY 4.0. The video stills in the paper were filmed by Kathryn Ayres (July 2024 event) and Héctor Franz (September 2025 event). Behavior-sequence diagram: generated illustration by the Impossible Universe Editorial Team.

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