Orcas and Dolphins Were Filmed Hunting Together for the First Time

In the cold, salmon-rich waters off Vancouver Island, British Columbia, scientists have captured something extraordinary: killer whales (orcas) and dolphins hunting together in a coordinated way never before documented.

The footage, recorded using drones, underwater cameras, and biologging tags, shows two of the ocean’s most iconic marine mammals seemingly cooperating to locate and catch Chinook salmon, a prized and powerful fish that forms a major part of both species’ diets. Researchers say the behavior could reshape our understanding of how highly intelligent predators interact in the marine world.

“We didn’t expect to see this level of interaction,” said Sarah Fortune, the lead author of the research and chair in large whale conservation at Dalhousie University. “Our footage shows that killer whales and dolphins may actually be cooperating to find and share prey, something never before documented in this population.”

An Unlikely Team on the Salmon Trail

Orcas and dolphins both belong to the family of oceanic dolphins, but they usually play different ecological roles. Northern resident killer whales (Orcinus orca) specialize in fish, especially Chinook salmon, while Pacific white-sided dolphins (Lagenorhynchus obliquidens) pursue smaller prey using rapid echolocation clicks to hunt in groups. Though researchers have long seen these animals near each other, they were assumed to be competing for food, not collaborating.

That assumption began to change when scientists studying salmon foraging behavior began tracking nine tagged northern resident killer whales in 2020. Along with drone and underwater footage, acoustic recordings revealed unusually close interactions between the whales and nearby dolphins. In 25 recorded encounters, the orcas appeared to track the dolphins’ movements and dives, turning toward them as they hunted and following them into deeper water.

According to the study published in Scientific Reports, orcas seemed to reduce their own echolocation and rely on the dolphins’ high-frequency sonar as they searched for salmon in deeper, murkier water, a behavior some researchers interpret as a form of acoustic eavesdropping.

A Shared Catch and Shared Rewards

During the same fieldwork, researchers documented eight salmon hunts in which northern resident killer whales successfully captured Chinook salmon. In four of those events, dolphins were present and swam within meters of the orcas. After the orcas captured and dismembered the salmon, a fish too large for dolphins to catch or swallow whole, the dolphins were seen scavenging leftovers that drifted away from the feeding whales.

That sequence, dolphins acting as fish locators and orcas as the powerful interceptors, suggests a mutually beneficial relationship. Killer whales may gain improved efficiency in locating salmon by trailing dolphins, while dolphins gain access to calorie-rich scraps they otherwise could not reach on their own.

Notably, researchers observed no signs of aggression between the two species during these hunts, an unusual outcome given that other orca populations sometimes prey on dolphins. This peaceful coexistence, coupled with in-field evidence of coordinated dives, hints that the interspecies interaction may be more than mere happenstance.

How Scientists Captured the Moment

To piece together the behavioral puzzle, the research team used a suite of modern technologies that are transforming marine biology. Drone footage offered broad aerial views of orca and dolphin movements at the surface, while suction-cup biologging tags attached to some of the orcas recorded underwater motion, sound, and depth data. Hydrophones captured echolocation patterns, and underwater video provided close-up views of the hunting sequences.

This combination of tools allowed scientists to see not only how the animals moved but how they interacted acoustically and behaviorally, providing richer evidence of coordinated hunting than any single camera could.

Not Everyone Is Convinced — Yet

Although the footage is compelling, some marine mammal researchers urge caution in interpreting the behavior as true “cooperation.” Michael Weiss, a marine biologist not involved in the study, told Live Science that while the dolphins clearly benefit from being near the whales, gaining food scraps and possible protection, it remains unclear whether the orcas benefit directly or merely tolerate the dolphins’ presence.

More research will be needed to confirm whether this hunting partnership is consistent across seasons or is unique to the salmon-rich waters of the Pacific Northwest. Understanding whether dolphins actively assist orcas, or whether orcas simply capitalize on dolphin acoustic cues, is an ongoing question.

What This Tells Us About Marine Intelligence

Even as scientists continue to debate the mechanism and frequency of the behavior, the discovery highlights the complex social intelligence of marine mammals and the dynamic nature of ocean ecosystems. These are animals capable of sophisticated communication and problem-solving, responding to the challenges of a changing environment in ways researchers are only beginning to appreciate.

For most people, the ocean remains a realm seen through documentaries or whale-watching tours. But what this latest research shows is that the sea still holds surprises, alliances, and behaviors that defy expectations and deepen our understanding of life beneath the waves.