Orcas have demonstrated a new and brutal hunting technique, captured on video as they repeatedly ram a sunfish, one of the world's largest and heaviest fish, until it explodes into thousands of pieces. This behavior was observed by marine biologists in the Gulf of California, a known feeding ground for sunfish that come up from deeper waters to warm themselves.
Sunfish can reach lengths of up to three meters and weigh as much as two tonnes. The recent observations in 2024 and 2025 documented a pair of orcas working together. In one instance, a female orca held the tail fin of a dead sunfish while a male accelerated and slammed into the fish, precisely releasing its grip just before impact. The force of the collision caused the sunfish to break apart.
Researchers are still investigating the purpose of this violent processing method. One theory suggests it could be a way for the orcas to feed their young, as juvenile orcas were observed feeding on the smaller pieces after the sunfish disintegrated. Adult orcas then consumed the remaining body parts, ignoring the scattered debris.
Another hypothesis explores potential nutritional benefits. Sunfish are protected by a thick, rubbery outer layer called a capsule. It is possible that by fragmenting the tissue, the orcas may expose and absorb more of the sunfish's unique microbiome, which could offer nutritional or immune-boosting advantages. Orcas are known for their intelligence and complex social structures, developing specialized hunting strategies for various prey. They have previously been observed coordinating attacks on large whales and using waves to wash seals off ice floes.
However, experts also suggest that this behavior might simply be a form of play. Orcas are known to engage in playful activities with their prey, such as the famous instances of orcas in British Columbia 'punting' dead seals into the air. While some scientists propose these playful actions could be a method for teaching young orcas or practicing hunting skills, others believe the animals might simply be entertaining themselves.
Dr. Kathryn Ayres, a marine biologist with Beneath The Waves who observed the behavior, emphasized the ongoing surprises that orcas continue to present. She noted the importance of collecting identification photographs of orcas to identify individuals and better understand their evolving hunting and prey processing techniques. Despite their iconic status, orcas consistently reveal new facets of their behavior, challenging scientific understanding.