This story was originally published in our September/October 2022 issue as ‘A Pod’s Bond’. Press here subscribe to read more stories like this.
Feet dragging in the water, I gripped the side of the boat, alert for my cue. As we crested a wave, the captain spotted something in the distance and shut down the engine. “Go, go, go!”
I fell with my friend into the Atlantic Ocean, its bottom thousands of feet below us. A moment later the boat was gone. We were alone. The water was as clear as the air above us; I felt dizzy as I floated over the abyss. All I could do was wait and hope. Then a huge figure appeared at the edge of my vision against the blue, and another, and another. Gradually the shapes became more distinct as they headed straight for me. I hung in the water, electrified by the sight – the largest predators on the planet, the fearsome protagonist of perhaps the most famous sea novel in literary history, Moby Dick.
I was face to face with sperm whales. I was in the Azores to study the social behavior of whales and went there with some trepidation. Although this group of mid-Atlantic islands has a permanent population of sperm whales, making it one of the best places in the world for biologists to study them, the Azores’ relationship with whales has not always been harmonious. Whaling was for many years an important part of the culture here, continuing until 1984. Although 27 years had passed since whaling in the Azores, it was likely that the adult sperm whales in the region had experience with humans as hunters. Reason enough, I supposed, for these intelligent beasts to be wary or even aggressive when they encountered us in the water.
In the past half century, there has been a sea change in the way we value whales – and their fellow cetaceans, dolphins and porpoises. Although our historical relationship as predators and prey unfortunately continues in some parts of the globe, most people now have some understanding of how complex and fascinating these creatures are, and know that they are imbued with intelligence that surpasses that of almost anyone else type of planet. In their societies, we see fascinating and enduring relationships, complex interactions, and compelling evidence of animal culture.
(Credit: Illustrations by Discover/Kellie Jaeger)
Diving deeper
When our team of four first set sail from Maddalena Harbor, however, we had only the most tantalizing glimpses of the whales as they disappeared into the blue. The small boat we used was manoeuvrable but didn’t handle big waves well, and finding whales is a challenge in rough seas. Every day of this initial period was a carbon copy of the last, washing up and down the Atlantic rolls, eyes peeled on the horizon, the only soundtrack being the intermittent, earnest vomiting of my companion Romain.
Our research was aided by the shining eyes of an ancient mariner, João, employed as a lookout and stationed in a hut in the middle of the volcano that originally gave birth to the island of Pico. It’s strange to think that João learned his trade and honed his skills by being a whale watcher years ago. Times had changed, even if his job hadn’t. But for four days, even the experienced Joao struggled to spot whales in the choppy sea. The telltale sign of whales is their snout, the steamy exhalation of air and bits of other, less pleasant things that shoot out of their blowhole at the end of a dive. A decent-sized whale can shoot its gust of moist air above the surface, but in rough seas you still need luck to find it.
Far below the waves the whales were feeding. They are amazing divers, capable of descending more than a mile in the darkness of the midnight zone for more than an hour at a time. In general, however, they don’t need to exert themselves so much – it all depends on where they can find their food.
To tip the balance in their favor, especially when hunting larger and more elusive prey, sperm whales coordinate and cooperate. They descend to their feeding grounds in pairs or small groups to form a search cordon, a line of whales spaced half a mile out to sea, a clever solution to locating clusters of prey. However, finding a thick patch of squid is only part of the battle. Tracks taken by underwater GPS devices fitted to the whales show that they split up to conquer – one whale dives under the squid to cut off their escape to deeper water, allowing the other whales to attack the flanks of the group booty. Nevertheless, our understanding of their hunting, like so many aspects of sperm whale behavior, is in its infancy.
Finally, on the fifth day of our trip, the waves receded. We finally had a chance. Sure enough, it wasn’t long before we heard the radio come alive and an excited voice spouting directions in Portuguese. The captain changed course and told us that a group of sperm whales lay a little over a mile to the northwest. If the whales decide to change course or dive, then that’s just bad luck. If there were to be meetings, they would be entirely on the whales’ terms. So we were expecting, at best, a few precious seconds with the whales as they passed – enough, if we were really lucky, to spot a few things, like identifying markings or markings.
But it was not only the oceanic agitation that had subsided; the whales also seemed in less of a hurry. Instead of passing them, they slowed down and suddenly we were in the middle of a family merriment. It was a phenomenal experience, greater than I dared to dream. But I couldn’t just hang on the surface of the water and enjoy it passively; bobbing whales kept coming dangerously close, forcing me to duck out of their way every time a powerful tail threatened to knock me spinning. The grouping was made up of four whales: a huge matriarch more than 30 feet long, a slightly smaller individual about three-quarters her size, and two calves. As wonderful as all this was in itself, the icing on our cetacean cake was an adult bottlenose dolphin with the pod.
The two species are tolerant of each other, but their different lifestyles and prey preferences mean they rarely bond. What may have solved the problem is that the dolphin had a distinct curvature of the spine, curving its body just behind the dorsal fin. It didn’t look like an injury (there was no scar), but rather something the dolphin carries from birth. Nevertheless, it had survived, against the odds, to reach adulthood. It is possible that the condition hindered his ability to swim at the relentless pace at which puffins normally travel. If so, it would have been isolated from the intense social life of its own species, and perhaps as a substitute had joined cetacean society.
For the next 20 minutes, the whales maintained a constant dialogue with each other, emitting their ethereal squeaks, stomps and clicks, while the dolphin’s higher-pitched call could be heard intermittently. The whales rolled in the waves on the surface, the smaller members of the group circling the huge matriarch. Then, even more amazingly, the whales began some strange game. The matriarch was opening her oar-like lower jaw and one of the smaller whales was swimming in her mouth, head sticking out one side and tail sticking out the other. The matriarch then appears to very gently bite the smaller whale for a second or two. The bitten whale would swim clear and circle around to join the rear of the tail, and another would maneuver in place for a bit of the same attitude.
The bottlenose dolphin also joined in on the fun, swimming into the matriarch’s open jaws for her turn and getting a toothy squeeze. I remained mesmerized by the encounter long after I had left the whales to play; it was an incredible privilege to see up close the remarkable social behavior of this little understood animal.
(Credit: Illustrations by Discover/Kellie Jaeger)
Forming connections
Back on land, I pondered what it meant for the whales to be held in the matriarch’s mouth for a moment. Perhaps there was some parallel with the maintenance behavior of primates. While the immediate role of grooming may be to keep the coat shiny and bug free, more important is what lies at the heart of it, the act of building and securing relationships. Because they lack dexterous limbs, of course, whales can’t do this. Perhaps it was their creative way of expressing themselves physically.
Sperm whales live in matrilineal social groups, the nucleus of which is formed by related females, often including a grandmother, her daughter and their offspring. Sons, on the other hand, live in these groups only as minors. As they approach puberty, males break away from their social group and adopt a more solitary existence – although it is not uncommon for males to form loose bachelor groups with one or more other males.
The group we saw that day was a fairly typical example of a sperm whale society, so it may be that what I witnessed was maternal attention paid to the family in the form of a strange cetacean hug. That the dolphin joined suggests that it realized no threat was involved, while the fact that the matriarch paid some attention to the dolphin suggests that it was accepted, albeit perhaps a temporary member of the group.
Social structures
In many ways, this unusual partnership raised more questions than it answered. For example, how was the dolphin able to search for food since it was burdened by its scoliosis spine? From the looks of it, it must have been well fed. He couldn’t forage with the whales because the dolphin couldn’t keep up with the amazing dives of his adopted family. Did he catch his own food? Or did the whales somehow provide it? Sperm whales sometimes bring their squid prey to the surface with them. Perhaps the dolphin was able to help itself with bites. This seems excessive, but no matter how much he was fed, the dolphin seemed to be an accepted member of the group.
It is a demonstration of the unusual structure of sperm whale society that this can happen. Among many similar groups of mammals, to be accepted into the fold, you must be related by blood. While kinship is important to sperm whales, it is not the only determinant of their associations. Genetic studies of their social bonds reveal that they form long-lasting relationships with both family members and outsiders. Although the dolphin may have taken this to an extreme, it suggests remarkable flexibility on the part of both species.
On the last day of the trip we did one last whale watching excursion. Luck was on our side—it had been four days since we first encountered the group of sperm whales with the dolphin, and here they were again, the dolphin still a big part of their scene. Weeks later, after leaving this marine paradise, we heard that our guides had again seen this group full of dolphin. It was a longer-term arrangement than I imagined; the dolphin interacted with the whale social group to a surprising degree. If nothing else, it gave us some insight into the extent of the social tendency of both species, the deep-seated drive to seek out and stay in company.
Sample from The social life of animals by Ashley Ward. Copyright © 2022. Available from Basic Books, an imprint of Hachette Book Group, Inc.
Ashley Ward is Professor and Director of the Animal Behavior Laboratory at the University of Sydney, where he studies social behaviour, learning and communication in the animal kingdom. His work has been published in leading journals including PNAS, Biological Reviews, and Current Biology.