Scientists have released incredible footage of northern transient killer whales following Pacific white-sided dolphins to help locate prey, then sharing the catch with them afterwards. The behaviour was recorded in the waters around Vancouver Island in British Columbia, Canada, and these interactions are not just chance encounters. Instead, the species appear to be working together to hunt Chinook salmon in waters off B.C., where they are often seen within metres of each other.
Notably, the two species showed no signs of aggressive or avoidant behaviour, and observations revealed that they frequently foraged in close proximity and often synchronised their movements. Killer whales were observed orienting toward dolphins and following them to depth, suggesting that the whales were eavesdropping and using dolphin echolocation cues to help locate the large salmon, a prey item that dolphins cannot capture and swallow whole. The videos reveal that once the whales caught their prey and broke them apart into smaller pieces to share with other killer whales, the dolphins were quick to scavenge the leftovers. The researchers say further investigation is needed to understand how widespread and consistent such co-operative behaviours may be.
The paper, published in the journal Scientific Reports, can be read here
