REFLECTION | DOLPHIN BEHAVIOUR

By Stephanie Huguenin-Elie – Sustainable Dolphin Watching Guide – Founder of Dolphin Whisper

Dolphin synchrony is one of the most beautiful sights at sea: dolphins swim, surface and dive as one. This rhythm may help calves keep up with their mothers, strengthen the bonds between companions and make a group appear stronger. To me, it is also a quiet lesson about cooperation, and about the way we humans could live together.

A rhythm I have watched many times

I have watched it many times, from the deck and from the water. Two or three dolphins rise side by side, exhale at the same moment, arch and slide back under, as if moved by one single pulse.

It never feels rehearsed. Instead, it feels like listening: each body adjusting to the others, without hurry, without any effort that shows.

And every time, something in me goes still. It is not the excitement of a sighting. It is something deeper, closer to recognition.

It never looks like a performance. It looks like listening.

What is synchronous swimming in dolphins?

Synchrony is when two or more dolphins move in coordination. They swim side by side, surface to breathe at the same time, dive together, and sometimes turn or leap in the same instant. It can be seen in many species, between mothers and calves as well as long-term companions, while travelling, resting or socialising.

I have often wondered what it means. However, from what I have read, there is not one answer, but several.

Why do calves swim so close to their mothers?

In its first weeks, a newborn calf often swims pressed against its mother’s flank, sometimes only a few centimetres away. This position is called echelon swimming.

This is because the water flowing around the mother’s body creates a kind of current. Hydrodynamic models suggest that a newborn riding in that flow could receive a large part of the push it needs to keep up, up to around 90% when the two swim almost touching. As the calf grows stronger, it spends less and less time there, and by its third year it mostly swims beside its mother as an adult would.

In other words, before it can swim on its own, the calf is, quite literally, carried.

Before a calf can swim on its own, it is carried.

Do dolphins breathe together?

Often, yes. In the first days of a calf’s life, mother and calf seem to surface together almost every time. Observations of Commerson’s dolphins suggest that this synchrony fades as the calf grows, and that the mother may even shorten her own breathing intervals to match her baby’s rhythm.

This detail moves me deeply, because here, care means slowing down to someone else’s breath.

Does swimming in sync strengthen bonds between dolphins?

In Shark Bay, Western Australia, male bottlenose dolphins form alliances that can last for years. A study published in 2025, combining drone footage with four decades of observations, found that allied males kept swimming in sync for longer after friendly contact, such as rubbing against each other. More surprisingly, males with weaker bonds seemed to synchronise most precisely.

The researchers suggest that synchrony may help these males maintain and strengthen their bonds. As if, when a relationship is fragile, moving as one becomes a way of saying: I am still with you.

When a bond is fragile, moving as one may be a way of saying: I am still with you.

Can synchrony protect dolphins?

Possibly, in some situations. In the Bahamas, the Wild Dolphin Project has observed groups of male Atlantic spotted dolphins coordinating their swimming, postures and sounds when facing a larger bottlenose dolphin. The researchers estimate that it may take around six of them to push back one large, aggressive bottlenose male. Together, they look bigger.

Similarly, among their deep-diving cousins, the beaked whales, extreme synchrony during dives appears to greatly reduce the risk of being detected by killer whales.

For dolphins facing predators such as sharks, however, synchrony itself has not been shown to be a defence. What we can say is simpler: a calf that stays close to its mother and its group is safer than one left alone.

What does dolphin synchrony echo in us?

This is where my own reflection begins.

When I watch dolphins breathe together, I think of all the ways we humans do the same. We walk in step, row together, sing in choirs, dance in circles and clap to the same beat. A baby falls asleep on a parent’s chest, its breathing slowly finding theirs.

Synchrony is one of our oldest languages too. For example, in one well-known experiment, people who had simply walked in step, or moved to the same rhythm, then cooperated more with each other and felt more like a team.

Maybe that is not a coincidence. Maybe moving together reminds the body of something the mind tends to forget: that we are not separate.

Moving together reminds the body of what the mind forgets: we are not separate.

What if cooperation is our nature too?

We often tell the story of nature as a competition. The strongest wins, the fastest survives. And we have built much of our way of living on that story: performance, speed, each of us for ourselves.

But when I watch three dolphins rising as one, I see another story. A mother adjusting her breath to her calf. Companions tending a bond by moving together. A group that grows stronger because no one swims alone.

Dolphins are not always gentle. They compete, they fight, they live complex social lives. But cooperation is woven into the way they survive. And I believe it is woven into ours too.

I often wonder what would change if we lived a little more like that. If, before rushing ahead, we noticed who was swimming beside us. What if we slowed down for someone who could not yet keep up, and tended our fragile relationships with the same patience, instead of letting them drift?

I don’t have a tidy answer. I only know that when I move in rhythm with others, without forcing anything, something in me feels alive, and right.

We were never meant to swim alone.

How can we protect these moments at sea?

Synchrony is fragile. It happens when dolphins are calm and undisturbed.

When a boat chases a group, cuts through it or approaches too fast, the rhythm breaks. In fact, long, high-speed chases are known to push calves away from their mothers and raise the risk of separation. For a calf that still depends on its mother’s flow, that distance matters.

So the most respectful thing we can do is simple. Keep our distance. Slow down. Never chase, touch or feed. Let the dolphins choose. And choose operators who know how to read the animals and who put their wellbeing first.

The most beautiful moments at sea are the ones we don’t interrupt.

Stéphanie Huguenin-Elie

Founder of Dolphin Whisper and advocate for ethical dolphin encounters.

dolphinwhisper.com – Ethical dolphin encounters

Further reading

Weihs, D. (2004). The hydrodynamics of dolphin drafting. Journal of Biology, 3:8.

Sakai, M. et al. (2013). Mother-calf interactions and social behavior development in Commerson’s dolphins (Cephalorhynchus commersonii). Journal of Ethology, 31, 305-313.

Hill-Cousins, S., King, S. L. et al. (2025). Allied male dolphins use synchronous displays to strengthen social bonds in a cooperative context. Movement Ecology, 13, 84.

Myers, A. J., Herzing, D. L. & Bjorklund, D. F. (2017). Synchrony during aggression in adult male Atlantic spotted dolphins (Stenella frontalis). Acta Ethologica. DOI 10.1007/s10211-017-0262-7.

Aguilar de Soto, N. et al. (2020). Fear of killer whales drives extreme synchrony in deep diving beaked whales. Scientific Reports.

Wiltermuth, S. S. & Heath, C. (2009). Synchrony and cooperation. Psychological Science, 20(1), 1-5.