Off the coast of Baja California, orcas have developed a distinctive hunting technique to prey on ocean sunfish, some of the largest bony fish in the world. These giants can weigh over 2,000 pounds and measure up to 14 feet from fin to fin, with thick skin that typically deters predators. However, in a recent study published in Frontiers in Ethology, researchers documented orcas using a forceful method to fragment sunfish, making them easier to consume and share with younger pod members.
The research, led by marine biologist Erick Higuera of Conexiones Terramar, includes footage from 2024 and 2025 that showcases the orcas’ coordinated behavior. In the videos, one adult orca grasps the carcass of a sharp-tail sunfish while another charges at high speed and rams into the fish upon its release, breaking it into smaller pieces. A juvenile orca is then seen feeding on the fragments, indicating a social feeding dynamic. Higuera described the attacks as “violent” and “chaotic,” yet “highly calculated,” likening the interaction to a soccer game where each individual has a specific role.
Orcas preying on sunfish has been observed for decades, including in the Gulf of California, where such encounters were first noted in the 1990s. In a study published earlier this year, Higuera and collaborators documented more than 20 interactions between orcas and sunfish, with calves present in several cases. The earlier research suggested that female orcas might use sunfish both as a food source and as a means to train young whales in hunting techniques or for play.
The latest findings reveal a more aggressive strategy involving thorough fragmentation of the prey, which may be particular to sharp-tail sunfish, differentiating it from previous observations where sunfish were not as extensively torn apart. Marine ecologist Robert Pitman of Oregon State University, who was not involved in the study, noted that this approach could help orcas access the nutritious interior of the sunfish without damaging their teeth, as sunfish skin is covered in tough dermal denticles similar to shark scales.
Other experts welcomed the detailed description of this behavior. New Zealand’s Marianne Nyegaard, who has extensively studied ocean sunfish and orca interactions, said the research brings greater ecological significance to sunfish, which are often overlooked as merely curious or marginal species. Luke Rendell, a marine biologist at the University of St. Andrews, pointed out that such hunting skills might be culturally transmitted within orca populations. He also compared the ramming tactic to orcas’ known behavior of ramming boats off the Iberian Peninsula, suggesting that these actions reflect a broader pattern of physical interaction with their environment used to gain knowledge or entertainment.
This growing body of research highlights the complex and adaptable hunting strategies of orcas and underscores sunfish as an integral part of marine ecosystems in the region.