Orcas ram sunfish so hard they explode, study finds

A new study reveals that orcas in the Gulf of California have been observed cooperating to ram sunfish with such force that the fish's bodies explode into small pieces. The behavior, documented in the journal Frontiers in Ethology, marks a distinct departure from typical orca feeding strategies, according to researchers. While orcas are known to use force to tear flesh from prey, this coordinated ramming appears to be a novel tactic.

The study's co-author, Kathryn Ayres of the nonprofit Beneath The Waves, suggests the behavior may help younger orcas feed more easily or could simply be a form of play. "Orcas are known for playing with their food," she said. The observations add to a growing list of unusual orca behaviors, including recent reports of orcas ramming boats—sometimes sinking them—which scientists believe may be culturally learned and passed down through generations.

The findings highlight the complex social learning and cooperative hunting strategies of orcas. Other documented tactics include ramming whale sharks while another orca holds the prey steady, herding mobile rays, blocking escape paths while hunting white sharks, and creating waves to knock penguins off ice floes. The researchers note that the sunfish ramming could serve multiple purposes, including social interaction, play, or practice for hunting.

The paper, published in Frontiers in Ethology, underscores the adaptability and intelligence of orcas. Further research may explore whether this behavior spreads through the population, similar to the boat-ramming trend seen in other regions. The study provides new insights into how orcas innovate and share hunting techniques within their social groups.