In a new study from the University of Exeter, drone footage has revealed that killer whales have complex social lives that center around close friendships. The researchers found that killer whales spend the most time interacting with specific individuals of the same sex and similar age.
In collaboration with experts at the Center for Whale Research (CWR), the team also discovered that killer whales become less socially connected as they get older.
“Until now, research on killer whale social networks has relied on seeing the whales when they surface, and recording which whales are together,” said lead author Dr. Michael Weiss.
“However, because resident killer whales stay in the social groups into which they’re born, how closely related whales are seemed to be the only thing that explained their social structure.’
“Looking down into the water from a drone allowed us to see details such as contact between individual whales.”
According to Dr. Weiss, the findings show that even within their tight-knit groups, whales clearly prefer to interact with certain individuals.
“It’s like when your mom takes you to a party as a kid – you didn’t choose the party, but you can still choose who to hang out with once you’re there.”
While examining patterns of physical contact, the experts found that both females and younger whales play a central social role in the group. The older the whale, the less central they became in the overall social structure.
The study was focused on more than four decades of data on a critically endangered population of southern resident killer whales in the Pacific Ocean. The researchers also analyzed 651 minutes of drone videos that they filmed over ten days.
“This study would not have been possible without the amazing work done by CWR,” said Professor Darren Croft. “By adding drones to our toolkit, we have been able to dive into the social lives of these animals as never before.”
“We were amazed to see how much contact there is between whales – how tactile they are. In many species, including humans, physical contact tends to be a soothing, stress-relieving activity that reinforces social connection.”
“We also examined occasions when whales surfaced together – as acting in unison is a sign of social ties in many species.”
“We found fascinating parallels between the behavior of whales and other mammals, and we are excited about the next stages of this research.”
The study is published in the journal Proceedings of the Royal Society B.