Whales help in the search for extraterrestrial signals

What do whales have to do with the search for extraterrestrial intelligence?

According to the WhaleSETI team, tonnes. The researchers are studying intelligent, aquatic, nonhuman communication systems to develop filters to help sift through cosmic signals for signs of extraterrestrial life.

In a similar way to studying Antarctica or other places on Earth as a proxy for Mars, the scientists from the SETI Institute and the University of California, Davis, are working to unravel the complexities of humpback whale vocalisations to pick up “patterns, meanings, and potential modes of interspecies communication.”

Now, for the first time, they report that that humpback whales produce large bubble rings during friendly interactions with humans. The phenomenon, which resembles smoke rings blown by some humans, could be a form of play or communication.

“Humpback whales live in complex societies, are acoustically diverse, use bubble tools and assist other species being harassed by predators,” says Dr Fred Sharpe, a behavioural ecologist at UC Davis and co-lead author of the paper in the journal Marine Mammal Science.

“We show they are blowing bubble rings in our direction in an apparent attempt to playfully interact, observe our response, and/or engage in some form of communication.”

Humpback whales are known to create bubbles in a variety of contexts, including thick walls of bubbles to round up prey and bubble trails and bursts when competing for proximity to females.

Bubble rings, while well-studied in toothed whales, including Atlantic bottlenose dolphins, beluga whales, and Orinoco dolphins, have only been seen sporadically in baleen whales.

The new study collated reports on 12 bubble ring events – including 39 rings produced by 11 individual humpback whales – which were collected by naturalists, citizen scientists, and researchers on boats or in the water.

The WhaleSETI team also contacted researchers who were using drones to monitor whales to see if the behaviour occurred the absence of humans. They found no such evidence. 

“Humpback whales often exhibit inquisitive, friendly behaviour towards boats and human swimmers,” says co-lead author Jodi Frediani, a marine wildlife photographer and UC Davis affiliate.

“We’ve now located a dozen whales from populations around the world, the majority of which have voluntarily approached boats and swimmers blowing bubble rings during these episodes of curious behaviour.”

Ring blowing during inquisitive encounters adds to the humpback whale’s diverse repertoire of behaviours towards other species, which includes the playful lifting of dolphins and human swimmers and inspecting the dead.

“Because of current limitations on technology, an important assumption of the search for extraterrestrial intelligence is that extraterrestrial intelligence and life will be interested in making contact and so target human receivers,” says Dr Laurance Doyle, SETI Institute scientist and co-author on the paper.

“This important assumption is certainly supported by the independent evolution of curious behaviour in humpback whales.”

In 1961, US radio astronomer Frank Drake came up with the equation for estimating the chances of intelligent civilisations in the galaxy. As Cosmos reported in 2024, Drake’s Equation has since gone through some updates.

“By integrating our findings into the broader context of Drake’s Equation,” the WhaleSETI team writes on its website, “we aspire to advance our understanding of the factors influencing the emergence of communicative intelligence in extraterrestrial civilizations.

“Through this interdisciplinary approach, our mission is to make significant strides in the quest to comprehend the prevalence and nature of communicative signals in the cosmos, ultimately contributing to the ongoing exploration of the potential for extraterrestrial life.”