Forget the Pseudoscience : All Fish Feel Pain

On Friday published one of my articles, which describes how the fisheries industry has taken control, not only of the planet's wild fish, but of how they are considered by the public as well.

My article describes a political situation which is being reported on more and more on the Internet—too much power is in the hands of the corporations. In this case, it is the fishing industry and its interests that have managed to maintain such control.

Among others, I used the article by David Shiffman and Neil Hammerschlag, that appeared recently in “Fisheries” as an example. In an effort to give the ring of scientific authority to shark fishing, it recommends “fighting” sharks through catch and release fishing, as a good way for Florida to earn money. But both cock fighting and dog fighting are illegal in Florida, so how can a student scientist be promoting the “fighting” of sharks?

It has been shown by a variety of scientific researchers who are NOT involved with fisheries, that sharks and fish do feel pain and suffer, and that shark fishing is harmful to them. The paper was a good example of how these animals are usually portrayed through the eyes of those who want to kill them, or who find it fun and exciting to brutalize them. As one who chose the route of actually observing these animals underwater in an effort to learn about them, I naturally spoke out.

Shiffman complained because his work was receiving criticism, though one wonders why he published it, if he did not want it read and discussed. By pressuring LiveScience, he managed to have the mention of his paper removed from my article, in a tirade of heated outrage in which he did not provide one bit of evidence in support of his position.

One can only hope that he will remove his fishy article from the literature as well, and analyze his data again. As long as it is online, anyone can look at it and judge for themselves if more shark fishing, or more shark diving, should have been the logical conclusion given the data. Do facts matter to fishermen? See for yourself.

As a result of my article being thus censored through pressuring from the fishing lobby, here is the full, uncensored article as it originally appeared on Live Science:

Forget the Pseudoscience : All Fish Feel Pain

Researchers at Yale Law School made headlines recently, when they suggested that people often fail to question their political beliefs in the face of scientific discoveries that contradict them. Their study showed how people reason selectively, and interpret data in such a way that it conforms with their political vantage point.

This phenomenon is evident in the pseudoscientific world of fisheries, a multi-billion dollar power that has taken control of both the planet's wild fish populations, and how these animals are viewed by the public. The result seems to be that irregardless of available facts, their conclusions are always in favor of fishermen, not fish.

Though rigorous scientific research has established beyond all doubt that the pain system in fish is virtually identical to that of mammals (Sneddon 2002), the fishing industry has maintained that fish are too simple-minded to feel pain (Rose 2002, 2012). As a result, most people seem to believe the old fishermen's tale that no matter how you brutalize fish and sharks, they won't suffer, and their abuse continues with almost no public outcry nor protest.

Yet no evidence has ever been produced to support the idea that an animal could live successfully, and survive, without the ability to feel pain, which is an important warning sensation. It would result in inappropriate behaviour, and the fish would go straight into evolution’s garbage can. Only a small percentage of fish who come into the world live to adulthood, and any weakness would doom them.

Neither do observations of fish behavior support the idea. Fish appear cautious and careful, and display cognitive behaviour in their efforts to eat food, such as sea urchins, that could sting them. Indeed, the evolution of such animals, as well as a host of other oceanic stingers, seems to have depended on the ability of fish to feel pain.

The subjective idea was dropped into the literature by the fisheries lobby, with no study done to support it, even though it failed to fit in with the facts already established scientifically, and observable to anyone.

The study of pain in fish

Since animals cannot tell us how they feel, scientists have searched indirectly for evidence about their subjective experiences, in the studies of neuroanatomy, neurophysiology and behavior. Researchers have developed strict criteria, all of which need to be met, before they can conclude that an animal can feel pain.

First, there must be nociceptors — sensory neurons that respond to tissue damage by sending nerve signals to the spinal cord and brain. There must be neural pathways from the nociceptors to higher brain regions, and the signal from the nociceptor must be processed in the higher brain, not in the reflex centers in the hindbrain or spinal cord.

There must be opioid receptors within the nervous system, and opioid substances produced internally. Painkilling drugs should relieve the symptoms of pain that the animal displays, and the animal should be able to learn to avoid a painful stimulus. This should be so important to the animal that it avoids the threat of pain right away. The painful event should strongly interfere with normal behavior — it should not be an instantaneous withdrawal response, but long-term distress.

Fish meet all of these criteria, as has been shown in a wide variety of experiments. (Sneddon et al 2003, Reilly et al 2008). Their nociceptors are nearly identical to those found in mammals and humans, and the nociceptors are connected to the brain through neurons. There are also connections between the different structures of the brain, including those that are considered crucial to the experience of pain. The whole brain of the fish is active during painful events.

In addition to neural activity, certain genes that are crucial to the experience of pain in humans are also found in fish, and they are active throughout the fish's brain during painful events (Reilly et al 2009). This activity of the brain at both the molecular and the physiological level, indicates that these are not reflex reactions. If they were, such activity would not be seen in the higher brain. (Dunlop R et al 2005)

Fish have displayed a variety of adverse changes in their behavior after the infliction of pain, such as an extreme increase in their ventilation (respiratory) rate, rubbing damaged body parts on the surrounding environment, rocking on their pectoral fins, trying to stay upright, and no longer feeding. These, and other symptoms of distress,are relieved by the administration of morphine, which completes the circle and identifies pain as the cause of the change in behavior. (Sneddon 2003)

Like other animals tested in laboratory settings, fish have been shown to self-administer painkillers if they can, even if that means going into a location that they do not like, to bathe in water that medicates them. This is another clue that the fish was suffering, and found relief in the undesirable location.

Fish swiftly learn to avoid painful events, which researchers think indicates that they are conscious — they experience the pain so severely that they are strongly motivated to avoid feeling it again, even after just one exposure. (Millsopp and Laming 2008)

Though humans can override pain at times in certain heightened mental states, and particularly when in danger, it seems that fish cannot do so. Studies have shown that after being hurt, fish become far less alert to danger, as if their pain is too overwhelming for them to ignore it, even to escape a predator. It is thought that due to their simpler neural design and mental states, fish lack the ability to think about their pain, and put it in perspective as humans can. Pain for them seems always to be an intense experience, which suggests that they may actually feel pain more intensely than humans.

When researcher Dr. Rebecca Dunlop of Queensland University, discovered that fish learn to avoid painful experiences, she wrote, "Pain avoidance in fish doesn't seem to be a reflex response, but rather one that is learned, remembered and is changed according to different circumstances. Therefore, if fish can perceive pain, then angling [fishing] cannot continue to be considered a noncruel sport."

The best way to relieve pain in fish during surgery has been meticulously researched. Pain relief is systematically used by veterinarians who perform surgery on fish, and the pain system in fish is considered to be the same as that in birds and mammals. Given that they are conscious, and may suffer on an emotional level, fish welfare emerges as an important issue. (Chandroo et al 2004)

Yet while amphibians, reptiles, birds, and mammals have been protected from cruel treatment, fish and sharks have not, thanks to the domination of those who profit from killing them.

Pro-Shark-fishing Scientists

The latest assault on sharks comes in the form of a pro-shark-fishing paper which was recently published in the journal “Fisheries” by David Shiffman and Neil Hammerschlag. It was financed by fishing interests, and recommends that Florida profit from the brutalization of sharks through repeated fishing and release.

The authors begin by citing French Polynesia as having set a precedent by valuing its sharks, (Clua et al 2011) but omit the point that French Polynesia's sharks are valuable because their population is protected from fishing and is relatively healthy. The country is the biggest shark sanctuary in the world, where the people never wanted their sharks either fished nor disturbed, and divers pay to see large congregations of sharks in an unmolested community.

There is no comparison with the shark-hate culture of Florida where sharks are under fishing pressure, have been fished out of large areas, and shark diving is not favoured. To see sharks, Florida's divers are obliged to go to the Bahamas.

The evidence of the success of diving enterprises in a place where sharks are protected from fishing, points to the conclusion that shark diving should replace shark fishing in Florida, and the beleaguered animals should be left in peace.

Yet the authors state :

“ French Polynesia, a single sicklefin lemon shark (Negaprion acutidens) can be worth over $2 million in its lifetime. . . Recent conservation advocacy, termed here “ecotourism conservation,” has used the economic premise that many species of sharks can be worth more to local economies alive than dead. . .”

For one shark to earn 2 million dollars for Florida, it would have to be fished 4000 times—2,000,000 dollars divided by 500 dollars, which is an average price charged by shark fishing charters to go out and catch a shark. Yet the authors do not address the possible effects on the lives and biology of sharks, as a result of being repeatedly “fought” nearly to death, at this intensity, for the amusement of certain elements in society.

Another problem emerges on a closer examination of the fisheries data presented in the paper itself. The blacktip shark is shown to be the most frequent species caught, and its survival rate from catch and release fishing is one of the lowest of all species shown. The authors state : “Blacktip Sharks and Great Hammerheads showed high physiological disruption and low survival following release.”

Yet, they also state many times that sharks are released “unharmed.” This contradiction with their own data is ignored. They show no evidence that catch and release fishing is “harmless” and fail to mention non-fishing scientific papers that present evidence to the contrary.

For example, a scientific paper published by Dr. Carley Bansemer and Professor Mike Bennett, of the University of Queensland in Australia, states that interactions with fishing gear resulted in “debilitating disease, morbidity, and death.”

The View Underwater
When fishing slaughter began among the sharks I had been studying, (Porcher 2005) the entire community fled, and it never reformed as it had been. Those who had escaped being landed, first appeared swimming unsteadily, and more weakly than sharks I had observed within 24 hours of death from natural causes. They displayed the same symptoms of pain I had seen in birds and mammals as a wildlife rehabilitator. They were less alert, less responsive, and they swam slowly, erratically, and often as if they were off-balance. The recovery of their normal swimming pattern when they lived, took up to two weeks.

Large hooks remained stabbed into their mouths and often into the jaw itself, where they interfered with the sharks' ability to eat. Some lost weight and died in the next months. The hooks took weeks, and in some cases months, to rust out. Sharks appeared during this time trailing lengths of fishing line that had become covered with algae to a thickness of several centimetres. Some continually jerked their heads away from the drag as if the heavy weight pulling on the hook in them was a steady source of discomfort. Juveniles appeared exhausted by it and disappeared before losing the hooks.

Sharks are not trout. They are large animals that have to swim continuously forward just to keep an adequate supply of oxygen moving over their gills, and their strong horizontal undulations are like a heartbeat, a powerful automatic motion they cannot stop. Their desperate efforts to escape death while pulling with so much force against a big shark hook piercing their faces or internal organs, can cause serious internal and facial injuries. And as any wildlife rehabilitator soon learns through experience, serious injuries to wild animals are usually fatal without the benefit of treatment and supportive care.

Fishing kills

One of the most famous American shark-fishing charter boat captains, Frank Mundus, was quoted by Russell Drumm in his book “In the Slick of the Cricket” as saying:

"Feeling good about tagging and releasing sharks was folly. The cheaper hooks bought by the weekend warriors were more often than not swallowed by the sharks which then fought their final battle gut-hooked. After being released, most sank to the bottom, dead. Maybe two out of twelve are hooked in the mouth. Add it up along the coast."

Much evidence that shark fishing is harmful to sharks, was ignored by the authors in their effort to give the ring of scientific authority to the brutalization of sharks for profit. But though their conclusions may be politically welcome, they are not biologically justified, and fall into the category of pseudoscience as defined as : a set of beliefs which is presented as scientific, but lacks supporting evidence or plausibility.

If you try to profit from cock fighting or dog fighting in the state of Florida, you are guilty of a felony, and now that it has been established that fish suffer as much as dogs and birds, there is no difference in terms of animal suffering among these blood sports.

But with tagging methods as the favoured means of gaining data on living sharks, their true natural behaviour remains obscure to many researchers. Their very approach to sharks through fishing and fisheries denies an appreciation of the real animals pursuing complex lives in their natural environment.

Not only is there is a deep cultural bias against sharks, but thanks to fisheries and the media, it is not even recognized. In the case of spiders and snakes, to take another example, everyone knows that they are disfavoured. But not in the case of sharks. Most people, including those who should know better, seem to continue to believe that the way sharks are portrayed by fisheries and in the media, is the way they truly are.

It is important that people begin to appreciate the true qualities of these unusual and important animals, in order to denounce this cultural situation, and insist that they be treated humanely in the interests of continuing to build a moral society.


Bansemer, C. S., and Bennett, M. B. (2010). Retained fishing gear and associated injuries in the east Australian grey nurse sharks (Carcharias taurus): implications for population recovery. Marine and Freshwater Research61, 97–103.

Clua, E., Buray, N., Legendre, P., Mourier, J., and Planes, S. (2011). Business partner or simple catch? The economic value of the sicklefin lemon shark in French Polynesia. Marine and Freshwater Research 62, 764–770.

Kahan, Dan M. and Peters, Ellen and Dawson, Erica Cantrell and Slovic, Paul, Motivated Numeracy and Enlightened Self-Government (September 3, 2013). Yale Law School, Public Law Working Paper No. 307.

Rose, J.D. (2002) The neurobehavioral nature of fishes and the question of awareness and pain. Reviews in Fisheries Science 10, 1–38.

Rose, J.D, Arlinghaus, R., Cooke, S.J., Diggles,B.K., Sawynok, W., Stevens, E.D and Wynne C.D.L. (2012) Can fish really feel pain? Fish and Fisheries, in press. DOI: 10.1111/faf.12010

Shiffman, D., Hammerschlagg N., Fisheries • Vol 39 No 9• September 2014

Sneddon, L.U. (2003b) The evidence for pain in fish. Use of morphine as an anaesthetic. Applied Animal Behaviour Science 83, 153–162.

Weber EP, Weisse C, Schwars T, Innis C, Klide AM Anesthesia, diagnostic imaging, and surgery of fish, Compend Contin Educ Vet. 2009 Feb;31(2): E11.

Every point I made above is supported by rigorous scientific research--I have included some of the most prominent, but it is easy to find more once one begins to research the subject in the literature. Countless studies on fish pain and their welfare have been done.


Popular posts from this blog

Fear of Sharks? A Comment on Aggression and Compassion in Humans and Animals

Rebuttal to Shiffman and Hueter, Shark Finning Fisheries Lobbyists