For many divers, the question of whether fish feel pain answers itself the moment we enter their world. We see it in the way fish respond to danger and interact with one another. They are not passive or mechanical, but responsive and engaged with their surroundings. Yet despite this, the widespread belief that fish do not feel pain has persisted for decades and been repeated often enough to be accepted as fact.
My new book, Yes, Fish Feel Pain: How Science Has Proven That Fish Can Suffer, brings together the growing body of scientific evidence that challenges this belief and explores what it means for the way we treat these animals. The gap between what science shows and what the public believes remains wide. This book is an attempt to close that gap by presenting the evidence clearly and by inviting a shift in perception, one in which fish and their environments are considered to have intrinsic value, as the important part of nature that they are.
The question of the suffering of fish appears simple, yet it has enormous consequences. Every year, trillions of fish are caught, cut open, crushed in nets or left to suffocate—far more animals than any other group on Earth. If they cannot feel pain, the moral problem can be said to disappear. But if they can, the situation looks very different. For much of what we do to them rests on the single, comforting belief that they are as sensitive as logs.
But the scientific evidence points in the opposite direction. The nervous systems of fish are designed to feel pain, and they react exactly as other animals do when hurt.
The belief that fish do not feel pain might have been comforting, but it was never true. The question is no longer whether fish feel pain. It is, “How long are we willing not to notice?”
Fishermen’s beliefs
I first learned of the claim that fish could not feel pain when shark finning hit the reef sharks I was studying. Fishermen wrote to tell me that I should not worry, because it had been scientifically proven that fish could not feel pain: They lacked the brains for any higher mental abilities.
I was incredulous. The oceans are filled with animals equipped with stingers, spines and venoms—defences that evolved precisely because of the sensitivity of fish to pain. Pain is a vital warning signal, coming from deep within the brain. It was self-evident that any animal that could not feel pain would go straight into evolution’s garbage can.
So I began developing my own arguments that sharks and fish must feel pain, as I wrote back to the fishermen. And, at the same time, unbeknownst to me, scientists elsewhere were beginning to test the question directly.
Fish do not have the right kind of brain
The claim that fish do not feel pain has rested on the fact that their brains lack the expanded, folded outer layer that is so developed in human brains: the neocortex. Since fish do not have one, it was assumed they could neither feel pain nor be conscious.
But modern neuroscience has shown that brains designed in different ways produce the same abilities, all across the animal kingdom. Life has found multiple ways to build thinking minds, and fish are no exception. The pain system is so vital to survival that it evolved in animals nearly half a billion years ago. The last ancestor shared by fish and humans could already suffer!
The fishing industry
The misinformation that fish cannot feel pain shields the multi-trillion-dollar fishing industry from scrutiny.
Large-scale fishing began in British and European waters with the development of steam-powered vessels in the 1870s. Increasingly, railroads connected fishing ports to towns in the interior, so that the market developed as the fishing fleets grew and fished farther from shore.
After World War II, large-scale fishing transformed into an industrial extraction machine, as huge factory ships—some longer than a football field—began sweeping across the oceans with nets capable of enclosing entire ecosystems. Their processing capabilities allowed them to stay at sea for months at a time. Trawlers dragged metal plates across the seafloor, pulverising coral forests and ancient sponge gardens, while purse-seine nets captured entire schools of animals in a single haul. Longlines stretching for tens of kilometres, with hundreds of thousands of baited hooks, killed everything that attempted to feed.
It took just one human lifetime for this industrial machinery to empty the oceans. Warnings from scientists that marine wildlife could not withstand targeted industrial hunting any more than terrestrial wildlife can were unheeded. By 2003, 90 percent of the predators were already lost.
Industrial fishing is not a quaint tradition. It is the marine equivalent of clear-cutting forests, strip-mining mountains and completely exterminating wildlife for profit. The ocean, once thought inexhaustible, has passed its limits. Fishing has caused the sixth mass extinction in the oceans and freshwater systems.
The scale of the suffering of fish is incomparable to anything else that humans inflict on animals, while the idea that fish cannot suffer, deliberately spread by industry strategists, has made this easier to accept.
The truth about fish
Today, the scientific debate is no longer about whether fish can feel pain. Instead, researchers are asking deeper questions about how their minds work and how widespread different forms of awareness may be in the animal kingdom. Public understanding, however, has not kept up. Many people still repeat the old claim that fish cannot feel pain.
This book looks closely at the evidence. In plain language, it explains what scientists have discovered about fish nervous systems, behaviour and cognition (the term used for thinking in animals), and why the arguments claiming that fish do not feel pain do not hold up. Along the way, we explore how evolution shapes minds, how animals experience injury and why our assumptions about intelligence actually say more about us than they do about them.
Most importantly, we look at fish themselves—not as objects, but as living animals navigating complex lives beneath the surface. Then, we consider the strategies used by the fishing industry to maintain the belief that fish cannot suffer, and how to translate the facts into messages that can easily be shared with others. Because changing public opinion is vital.
A cultural shift
I believe that the recognition of fish sentience and the remarkable intelligence of these animals is part of a profound shift in human consciousness. The scientific findings of conscious awareness all across the animal kingdom should lead to a new way of thinking about the myriad of other life forms, all interacting to create the biosphere that makes our lives possible. Then, we begin to understand consciousness as a vast, branching tree of unimaginable variety, rather than a ladder with us on the top rung.
We are just one expression of awareness among trillions. With this perspective, we cannot help but value nature and the mystery of it all being here on this small planet, surrounded by so much dark and uninhabitable, chilling space.
Once we understand what science has revealed, the question is no longer whether fish feel pain. The real question is what we choose to do with that knowledge. For once our eyes are opened, it is hard to go on living with them closed.
Yes, Fish Feel Pain is now available. For divers, it offers a scientific perspective on something we have already known: that fish are far more complex, aware, sensitive and intelligent than they are generally believed to be. And divers know fish best and are in the best position to spread the word about their true importance in nature. I hope this book will be of interest to you. I made sure that there is beauty in it, as well as information. ■
Ethologist Ila France Porcher, author of Yes, Fish Feel Pain, The True Nature of Sharks, and six other books on wildlife behaviour, conducted a seven-year study of reef sharks in Tahiti, resulting in several scientific papers. Her writings are based on decades of first-hand observations of wildlife—from sharks to bears to birds—and focus on the individuality and intelligence of wild individuals, challenging traditional views of animal minds. Her work has been featured on Shark Week, in scientific discussions, conservation debates and international media for its unique blend of field observation, art and science.
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