Orcas team up with dolphins to hunt salmon, study finds

"Orcas and dolphins have been spotted working as a team to hunt salmon off the coast of British Columbia, according to a new study which suggests a cooperative relationship between the two predators. The research, published on Thursday in the journal Scientific Reports, shows interactions between northern resident orcas (also known as killer whales) and Pacific white-sided dolphins are not just chance encounters while foraging."

"Dolphins have often been spotted close to the northern resident orcas, an ecotype of the apex predator that subsists almost entirely on Chinook salmon. Dolphins lack the ability to hunt salmon, which are too big for them, normally relying on herring. Video footage in the research shows the dolphins which Fortune said act as scouts cutting seamlessly through the glassy waters of the Pacific in pursuit of the salmons, which can reach nearly three feet in length. The orcas follow closely behind."

Northern resident orcas and Pacific white-sided dolphins have been observed coordinating to hunt Chinook salmon off the British Columbia coast. Extensive drone, acoustic and underwater recordings documented repeated, non-random interactions indicating cooperative behavior. Dolphins, which normally hunt herring and cannot capture large salmon, appear to act as scouts by cutting through glassy waters to pursue salmon, while orcas follow closely and capture prey. Orcas break apart salmon at the surface and share portions with pod members, leaving leftovers that dolphins scavenge without provoking aggression from the whales. The proximity and tolerance suggest a stable, mutually beneficial feeding association between the two species.

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