The ocean is cold and unforgiving. Predators chase prey, males fight for mates, and pods relentlessly defend their turf. Yet, amid all this perpetual contest, scientists keep stumbling on something remarkably wholesome. Dolphins and whales, two very different kinds of marine mammals, sometimes seem to seek each other out — not to compete, but to linger, to play, and, in some cases, to form what looks suspiciously like friendship.
The Mammals of the Sea
Dolphins and whales are both mammals. They’re also intelligent and social creatures (some species more than others), so it’s not entirely surprising that they would occasionally bond. Heck, biologists think humpback whales are even trying to communicate with us landlubbing humans. However, interspecies interactions are extremely rare in the animal kingdom, let alone in the vast ocean.
In fact, the general assumption had previously been that whales and dolphins are rarely in contact at all. This new research contradicts that.
Jan-Olaf Meynecke and Olivia Crawley, two researchers from Griffith University in Australia, combed through whale-dolphin interaction events involving 19 different species. These interactions spanned two decades and occurred across 17 countries. Many of them came from social media or videos taken by citizens. They reviewed each entry closely, validating the species and then classifying the interaction.
“We categorized behaviors such as rolling, tail slaps, bow riding, and rubbing, and classified dolphin positions relative to whale body parts such as head, flank and tail fluke,” Meynecke writes in an article for The Conversation.
Whale-dolphin interactions. Image courtesy of the researchers.
Most often, dolphins would go near the whale’s head, akin to bow riding. Bow riding is a documented dolphin behavior where dolphins use the pressure front created by the bow waves of ships to swim in a more efficient manner. Simply put, dolphins are being pragmatic. But sometimes, there seemed to be some genuine, back and forth, interaction. Humpback whales often rolled and exposed their bellies; they would turn gently towards the dolphins, and dolphins would do the same thing.
Quite often, their interactions seemed to have no practical purpose at all. In fact, researchers suspect that around 1 in 3 of all interactions are some form of play, dolphins and whales just hanging out and enjoying each other’s presence.
This behavior also isn’t accidental. Whales and dolphins didn’t just come across each other, they would seek each other out.
But Why?
Of course, there’s a fair bit of speculation when trying to interpret what other species are thinking. But in this case, the simplest answer seems to be the most plausible one: because they like it.
Us humans are social creatures (again, some more than others). We seek out the company of others, especially individuals we can bond with. Dolphins and whales may be doing the same thing. This suggests that interspecies interaction, at least among some creatures, may be far more prevalent and complex than previously believed.
“Dolphins may seek out whales as companions for stimulation, play or even courtship-like behaviour. Meanwhile, certain whale species, particularly humpback whales, may not only tolerate but also engage with dolphins in a social capacity,” Meynecke adds.
“This interspecies dynamic adds a new dimension to marine mammal social ecology and could point to cultural elements in whale and dolphin societies. The playfulness, cooperation and apparent enjoyment observed in many interactions reflect advanced cognitive and emotional capabilities.”
The reason why we haven’t discovered more of this is that it’s hard to look for.
This type of analysis wouldn’t have been possible without recordings made by hundreds of people. The oceans are vast and difficult to scour, you never know when this type of interaction will emerge. People’s recordings are often imperfect and their equipment isn’t well suited for the task, but it’s a great help for scientific observations.
Drones are another useful source of information, as they can record interactions visible from the surface with minimal interference. With citizen science and new technologies, researchers hope to find out more about these intriguing behaviors.
Dr. Andrei Mihai is a geophysicist and founder of ZME Science. He has a Ph.D. in geophysics and archaeology and has completed courses from prestigious universities (with programs ranging from climate and astronomy to chemistry and geology). He is passionate about making research more accessible to everyone and communicating news and features to a broad audience.
