Orcas and dolphins spotted 'working as a team' to hunt salmon

Orcas and dolphins have been spotted working as a team to hunt salmon off the coast of British Columbia, according to a study that suggests a cooperative relationship between the two predators.

- Leyland Cecco

The research, published yesterday 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.

Extensive documentation, including drone video, acoustic recordings and underwater footage, led scientists working with the University of British Columbia, the Leibniz Institute and the Hakai Institute, to conclude the two species are working as a team.

“These whales are top salmon hunting specialists. They’re highly specialised and highly skilled predators. To see them following dolphins as though they were leaders was really counterintuitive - and really exciting,” said Sarah Fortune, a marine scientist at Dalhousie University and the report's lead author.

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.