Deciding To Die: Dolphin Suicide

January 19, 2016 Laura Bridgeman


Is dolphin suicide real? The stories and science suggest that it is. 

In his book Naturalis Historiae published in the years 77 – 79 AD, Greek naturalist Pliny the Elder wrote about a touching friendship between a dolphin and a young boy. According to Pliny’s account, the pair spent many hours gamboling about together in the sea.

Sadly, this relationship came to an abrupt end when one day, while riding through the water on the dolphin’s back, the boy “lost his life in the waves of a sudden storm.” The dolphin brought the lifeless body back to the shore and, according to Pliny, “the dolphin, confessing itself the cause of his death, did not return out to sea and expired on dry land.” He goes on to say that another scribe named Theophrastus recorded that “exactly the same thing occurred at Naupactos too.”

The word ‘suicide’ seems to be most appropriate in describing this stranding event. Yet there are still doubts as to whether a dolphin, or any other animal, has the ability to commit suicide. Because the act involves such complex emotional and deeply personal processes, we assume that suicide forms another pillar in the grandiose structure of human exceptionalism. But if we look at stranding incidents and explore potential underlying motivations, we may glean insights into the cetacean mind and their myriad, complex cultures. And we might learn something about our own nature along the way.



While Pliny’s account remains one of the earlier recordings of a cetacean stranding, these types of incidents remain common today. Reports constantly come in from around the world: in April 2015, one of the largest recorded stranding events occurred when 160 melon-headed whales beached themselves while alive in Japan. Earlier this month, 81 pilot whales stranded in India.

While the reasons for cetacean strandings often remain a mystery, we do know that some species are more prone to stranding than others. Many odontoceti (toothed) species, like sperm whales and dolphins, strand while still alive, while others tend to wash ashore posthumously. Some of the most puzzling incidents involve entire pods of dolphins who strand en masse, all in good health save for one stricken individual.

In some cases, reasons for the stranding are apparent, for example when signs of disease, injury or infection are present. Sometimes, pollution generated by humans is presumed blamed. One of the leading causes of strandings likely results from Navy war games and the oil industry, as they blast sound cannons into the ocean and literally shake cetacean’s acoustic systems to pieces, to the tune of thousands of deaths per year.

Sometimes, though, a cause cannot be determined. In these cases, official explanations for strandings are many, yet seem lacking: the cetaceans may have been chased out of the water by a predator; the oceanic topography might have confused them; or just plain old weather conditions.

Despite humans being the cause for many strandings, Pliny’s account shows us that cetaceans have been stranding long before our disruptive activities entered the scene. The focus of this piece will be on those strandings of otherwise apparently healthy individuals who thrust themselves ashore.


An Intentional Act

While they may be valid in some cases, the official explanations offered rarely – if ever – account for autonomous decision-making on the part of the cetaceans themselves. This oversight is worth exploring. Dolphins can control many aspects of their physiology that come as automatic and unthinking features of our own – kind of like the difference between driving a standard and an automatic car. Each breath they take is a conscious and coordinated effort. Males can command and withdraw penile erections on a whim. It has also been speculated by that females might be able to pick and chose whose sperm fertilizes her egg. So, dolphins making pointed decisions about when to end their lives may not be so outlandish.

Some people deny a cetacean’s ability to commit suicide because they do not believe that dolphins have sufficient brainpower. Yet a growing number of scientists disagree, among them neuroscientist Lori Marino. In her article, Suicide in Dolphins: A Possibility? Marino states that the constantly-growing body of evidence that indicates a dolphin’s “sense of self… the cognitive ability to think about oneself… and the ability to think about and plan for the future” clearly underwrites “the capacity for such complex intentional actions as suicide.” If you would like more examples of this body of evidence, just have a look at some of the other articles on this site.

Pliny is not the only person to hint at intentionality behind these deaths. Within human-controlled conditions – i.e. captivity – we find many accounts of apparent cetacean suicides. In some cases, it is thought that they simply shut their blowhole and refuse to take another breath. Perhaps they do this in lieu of stranding because they are not afforded that option in artificial tanks. Asphyxiation certainly seems like a preferable way to die, and maybe it is out in the open ocean. It is important to keep in mind that, just because this has not been observed in the wild, doesn’t mean it never happens.

Even equipped as he was with less scientific knowledge of dolphin behavior and physiology than we have today, Pliny clearly insinuates that the stranding he recorded was an act of deliberate suicide. He would likely scoff at our contemporary “objective” scientific suggestions that it was a coincidence, or that the dolphin behaved only as though he was confessing himself of the crime. Instead, on Pliny’s mind were questions of whether the motivation resided within a deep mourning of the human friend, a form of self-punishment, or some combination thereof. While we will never know the answer, there was apparently little doubt in Pliny’s mind that this was an intentional act, motivated by what could have been a relentless onslaught of painful emotions.

Intentional stranding would certainly not be a decision for a dolphin to take lightly. A cetacean’s death on terra firma is a prolonged, painful process. They can literally bake to death in the sun if it’s a hot day. In cooler climes, the full force of gravity slowly but surely crushes their internal organs under the weight of their own bodies. Either way, there is plenty of time for the contemplation of their circumstances. The thought of such a death is likely what leads many to believe that wherever a living cetacean strands, it couldn’t possibly be voluntary.

Methods notwithstanding, many of us can relate to the desire to control the timing and circumstances of one’s own death. Arguably this is something to which we are fundamentally entitled. Yet, in western cultures at least, there is a tendency to prolong life at all costs – often resulting in profound and unnecessary suffering. In the eyes of major religions like Christianity and Islam, human suicide was traditionally considered to be a sin and it remains illegal in many places. The United Kingdom continues to refuse its citizens the right to die. In the United States, only a handful of states allow people to make this decision, including Oregon with their recent Death With Dignity Act. While calls (and outright pleas) to be given the right to die are becoming louder, there is still some ways to go.

One has to wonder what the dolphins would think of this.


Collective Departure

While members of our own species might be able to relate to an individual dolphin’s decision to die, there exist few, if any, human societies that share the group suicide tendency of cetaceans (assuming that some mass strandings are, in fact, suicides). Autopsies performed on stranded pods after they have perished often reveal that only one member of a stranded group was ill, with the rest in good health. In August 2015 in Nova Scotia, 14 pilot whales beached and it was thought that only one individual was sick. One explanation given in this situation was that the pilots had misjudged the tides and become trapped. Are we really to believe that this species, equipped with what is likely the most sophisticated sensory system on the planet, in fact misjudges such things? Perhaps.

Perhaps, though, there is more to the story. Because their sonar gives dolphins uncanny insight into one another’s bodies, they may be able to watch the onset of grave illness within one another. Dolphins have been known to detect cancer and other diseases in humans, and appear to demonstrate an understanding and appropriate concern regarding the human’s health. These anecdotes seem to suggest that dolphins do monitor one another’s health. If this is true, they could have a better understanding of when to tag out, and maybe even come to a consensus of doing so together.

Suggesting that an entire pod of dolphins might have the courage to face death in such a deliberate manner, and choose to do so at the prospect of losing one or several of their own, is controversial. This is not to say that all dolphin societies do this or that they always stick together – in some cases, when a dolphin becomes sick or is suffering after a shark attack, she will strike off on her own until she heals and rejoins the group. But healthy pods stranding with only one or two compromised individuals in their midst does raise interesting questions. Given the size and structure of their limbic system, the emotional pain of living without one member of their pod could be too great to bear. Maybe for dolphins, physical pain pales in comparison to emotional wounds.


In the Face of Death

Wherever cetaceans strand, our instinct is to run to the rescue. We have stranding networks that do noble work and have successfully returned many individuals to the sea. But these actions are based entirely upon our human moral constructs, guided by our notions that we always know what’s best. We assume that the cetaceans want us to do everything possible to prevent what we perceive to be the horrifying inevitability of death. Truth be told, however, we can’t know for sure whether they want to be back in the water.

It’s safe to say that much of our aversion to death is grounded in a fear of the unknown. This is why we sometimes irrationally hold on – to our own lives and those of our loved ones – when it would be more humane to let go. Facing death as an inevitability, something that is every bit as natural and normal as being born, is not something our modern cultures tend to emphasize.

This might be where our species again differs from the cetaceans. Could it be that they have an entirely different view of death, and thus of life, than we? Might they view death not as something to be afraid of, but something to do, together, with their loved ones? Are they not so attached to their individuality and therefore not so terrified of losing it?

This could partly explain the enduring mystery of why cetaceans never attempt to jump over the nets of Taiji fisherman or fight their assailants. Perhaps they accept the end when they see the writing on the wall, content at least to die together. If this were the case, then the fishermen forcing a handful of traumatized individuals back out to sea, and keeping others for a life in captivity, may be punishments crueler than we can possibly imagine.

In a way, stranding is like a reverse human birth. The oceans are nearly identical in composition to the amniotic fluid of the mammalian womb. Cetaceans are born from their mother’s internal ocean into the collective womb of the sea, never touching dry land until, sometimes, at the very end. Intentional or not, stranding is a representation of the cyclical nature of existence, the ultimate rebirth.

We may never know why cetaceans die the ways they do. But the questions that arise should compel each of us to rethink the ways that each of us die. Maybe death is not something to fear. After all, it is the most natural thing in the world.


Photo by Atmo Kubesa.