Killer whales have close friendships, drone study reveals

Killer whales have close friendships and prefer to spend time with other whales in their pod who are of the same sex and of a similar age, new research suggests.

A study that used drones to film orcas revealed complex social structures among them. As they get older, whales grow apart and play a less central role in the group. Younger whales and females are more central to the pod, the research found.

The study was based on data collected over four decades on southern resident killer whales, a critically-endangered population in the Pacific Ocean.