‘Immigrant whales’ bring ancient feeding culture to recovering Canadian humpbacks

Bubble net feeding is being brought to groups of humpback whales in Canadian waters by ‘immigrant whales’, which scientists think is crucial to the success of their recovering population.

The study published today in Proceedings of the Royal Society B shows that the recovery of humpback whales in the northeastern Pacific depends not only on population size, but on the spread of the culturally learned feeding behaviour across the whales’ social networks.  

Bubble-net feeding is when a group of whales work together to blow clouds of bubbles that gather their small fish prey schools into higher densities that they can then engulf together. It is a cooperative and highly social behaviour that requires whales to learn how to work in a group.

The feeding tactic has been seen for decades in the waters of Alaska. However, whales in Canadian waters either didn’t know or had lost the knowledge of the technique.  

The research was conducted in Gitga’at First Nation territory, within the Kitimat Fjord System of northern British Columbia, Canada – an area that has been stewarded by the Gitga’at First Nation for millennia and is known for its ecological and cultural importance. 

As the Canadian Pacific population of humpbacks has begun to recover from whaling, bubble netting has begun to spread and be adopted by those groups of whales too.