Overview
- Scientific Reports published the first recorded evidence of cooperative foraging between northern resident killer whales and Pacific white-sided dolphins on Dec. 11, 2025.
- Researchers logged 25 cases of orcas changing course to follow dolphins on foraging dives, eight salmon captures shared among orcas, dolphins present for four, and one confirmed scrap scavenging by dolphins.
- Data came from nine tagged whales using suction-cup video and movement sensors, synchronized with aerial drones and underwater acoustics collected in August 2020 around Johnstone and Queen Charlotte straits.
- Sensor records show orcas often reduced their own echolocation when near dolphins, supporting a hypothesis that whales may eavesdrop on dolphin clicks to locate deep Chinook, while dolphins gain access to leftovers and possible protection.
- No antagonistic behavior was observed during the interactions, but authors and outside experts say broader sampling is needed to confirm how widespread, persistent, and beneficial this behavior is, and some researchers question whether it reflects true cooperation.