Located on Sydney’s Northern Beaches, it is closely associated with swimming, surfing and coastal recreation.
The Northern Beaches Council describes Manly as one of the area’s prominent beaches and notes that it is patrolled throughout the year.
Surf culture is an everyday part of the landscape.
On a normal morning, human surfers wait beyond the breaking waves for the right swell.
Against that backdrop, a pod of dolphins appearing to surf together creates an irresistible visual comparison.
Humans have spent generations learning how to use waves for speed and recreation.
Dolphins, of course, were doing it long before surfboards existed.
That contrast helped the photographs resonate.
Viewers were not simply looking at animals swimming.
They were looking at animals apparently doing something immediately recognizable as surfing.
The Science Behind Riding Water
A moving wave carries energy through water.
An animal positioned correctly within that movement can take advantage of hydrodynamic forces rather than relying entirely on muscular swimming.
This principle helps explain why dolphins may surf ocean waves and the pressure waves generated by vessels.
Researchers studying bow-riding have noted that dolphins can use the moving water around a vessel in ways that affect the energetic cost of travel. But scientists continue to debate how much of the behavior is transportation and how much may be voluntary play.
Context is crucial.
If dolphins use waves while traveling in a particular direction, energy efficiency may be important.
If they interrupt other activities to repeatedly approach waves or vessels and then return, play becomes a more plausible explanation.
This flexibility is part of what makes dolphin behavior so fascinating.
The same movement may serve different purposes at different times.
A leap can communicate.
It can occur during conflict.
It can help with travel.
It can be playful.
Similarly, surfing may be practical in one situation and recreational in another.
The photograph from Manly cannot resolve that scientific question.
But it provides a spectacular example of a behavior that marine-mammal researchers have been studying for decades.
Dolphins Are More Playful Than Many Adult Mammals
Play is particularly interesting to animal-behavior scientists because it can seem inefficient.
Animals need energy for finding food, avoiding predators, reproducing and caring for offspring.
Why spend energy doing something without an obvious immediate survival benefit?
One explanation is that play has longer-term benefits.
It can help younger animals develop physical coordination.
Social play may allow animals to practice interactions and learn the limits of acceptable behavior.
Object play can help animals explore their environment.
In dolphins, researchers have documented remarkably inventive forms of play.
They may manipulate seaweed.
They may interact with bubbles.
They may chase one another.
They may surf waves.
Some research has even documented unusual socially transmitted behaviors spreading through dolphin communities.
A study of Indo-Pacific bottlenose dolphins in Australia, for example, described the spread of “tail walking,” an unusual behavior in which a dolphin raises much of its body vertically above the water while moving backward using its tail. Researchers concluded that social learning was the most likely explanation for how the behavior spread through the community.
Such observations reinforce the idea that dolphin societies are dynamic.
Animals watch one another.
They learn.
They imitate.
And at least some of what they do appears to exist beyond immediate survival needs.
What We Should Not Assume From a Photograph
A powerful wildlife image can tempt people to create a story around it.
The dolphins look happy.