Do Fish Feel Pain? And Do Fish Feel Pain When You Clean Them?

Watch a cat hit its head into the wall, or seeing a dog get hurt in the process of chasing after something, in any case, their agonizing meow or howl can tell they feel pain. What about the little guy in the fish tank?

Does a fish even feel pain? If so, does it feel pain when I clean them? The thought of never having explored this haunted me. Many of us are guilty of taking care of a fish carelessly because we can’t really tell if it is feeling pain or not.

Read further and learn everything you need to know about whether or not a fish feels pain.

The Answer

Many fishermen would disagree, but the unchangeable truth is, fish feel pain. They can be hurt in so many ways, emotionally and physically. How? Research suggests that a fish living in small spaces like fishbowls are more aggressive than the fish in the open sea. There is more to fishes than you know, they can feel pain at different levels.

Scientifically, fish’s nervous systems do, in fact, respond to anything harmful, which is called nociception. What does this mean? It means, when you stick a fish with a needle, it will flinch and swim away. When it’s inflicted pain, there is a response. Therefore, scientists conclude that a fish can and does feel pain.

There is a lot of counter-arguments out there, but in recent years, there is growing evidence to support the claim that fish feel pain.

Do Fish Feel Pain? (Video)


Emotional Pain

Majority of humans suffer greatly from emotional pain. So, the question is, do fish feel emotional pain too? Do they also feel pain after a breakup? Researchers who have studied this question found that fish also feel emotional pain.

Scientists studied a couple of fishes without their consent. It’s not as bad as it sounds, we learned that a fish is emotionally hurt after a breakup. When the female fish lost her chosen mate, it became glum and pessimistic. It’s true! A fish with the experience of a broken heart would supposedly stick with the safer option. This is evidence of a change in behavior after an emotional experience, which proves that fish feel emotional pain.

Physical Pain

Let’s dig a bit deeper. It is clear that fish feel pain, but can I be really sure? There is a set of criteria which is used to see if an animal feels physical pain or not. What is this checklist? Check it out below.

  1. Nociception

    For starters, we have the nociception – we talked about this earlier to confirm if a fish felt pain.

  2. Opioid Receptor

    Opioids are nature’s answer to pain. The pain killer, if taken artificially, can prove to be addictive. If there is pain, our body resolves it with a natural pain killer, and a fish has both; pain receptors – nociception and the ability to reduce pain – opioid receptors.

  3. Physiological response

    Scientists have observed electrical brain activity when a person feels pain. While researching fishes, they found a similar response. When exposed to something harmless like a brush, the fish doesn’t react, but when you try to poke them with a needle, they will make a swim for it.

  4. Motor Reaction

    “Fool me once, shame on you. Fool me twice, shame on me.” The iconic phrase is the perfect example of how humans react to pain. So, for instance, let’s say you pricked a fish using a needle. At that point, the unsuspecting fish didn’t know what a needle can do. After you hurt it, the fish has a better sense. So, the second time you try to poke it with a needle, the fish will swim away to avoid the pain it felt the last time.

  5. Trade-offs

    Some people claim that the motor response to the needle is an instinct rather than a reaction. However, like humans, the way they behave also changes with experiencing pain. Similar to the way a fish reacts to the needle the second time around, we can say that it has a different behavior too. If you try to poke it from the left area of the fish tank every time, the fish will eventually stop swimming in that area.

  6. Sentience

    The fact that a fish tends to avoid places and objects that can cause pain is proof of their sentience. Scientists are yet to figure out if this level of cognitive activity means fishes are equipped with the ability to cope with pain.

Do They Feel Pain Like Humans?

A fish feels pain differently from the way humans do. This is because their nervous system is simpler compared to humans. While some fish do have nociceptors, these receptors are different from the ones humans possess. The humans have c-nociceptors which allow them to experience pain more intensely.

Additionally, there are some doubts regarding the behavioral response to pain. Basically, they think that behavioral change was a result of an emotion – pain. Buuut, when a fish is exposed to morphine, it had no reaction. The fish either doesn’t feel anything, or it feels it so intensely that it’s shocked to stillness. So, the question which needs answering is; do fishes react to pain instinctively, or is it an emotional response?

Before I answer that, let me tell you about the other side of the argument. They gathered some fishes and exposed their lips to something painful. They reacted by rubbing their lips on the tank. Does it remind you of something? What do you do when you hit your toe? You rub it.

Now, with all this information, I will let you decide whether or not a fish feels pain like humans. With each passing day, there is more evidence to support the claim that a fish does feel pain.

Should we care?

Considering that fish feel pain somewhat like the way humans feel pain, the question is, should we care? Regardless of whether or not a fish feels pain, it is morally wrong to inflict pain on any animal. Should we care? Yes, of course. Now, how you use this information is up to you. I’d advise you to simply handle fishes with a gentle touch. When you decide to gut a fish, just wait till it is dead. This could take somewhere between 25 to 250 minutes. Common sense should dictate that a fish does suffer and feel pain, to what extent? We may never know the answer, but without a doubt, I strongly believe we should care – after all, that is the humane thing to do.

Emotional Intelligence

Perhaps the question I should be asking is, are fish intelligent? Does it have the emotional intelligence to experience and avoid pain like humans? Let’s find out. So, there was an experiment conducted to test the fish’s intelligence, and the findings are shocking! The one finding that concerns us is their memory. It turns out a fish remembers things longer than we think. It will recognize an old friend and a neighborhood they used to live in. Meaning, it has the ability to remember a fish and places where it felt pain. How do we know? There was a mirror test to see if they would recognize themselves. The test proved that a fish can recognize itself and others. It even has the tenacity to cooperate with other fishes. So, essentially, what this means is that the fish is capable of living on their own.

Ending note: No, your golden fish doesn’t have a three second long memory, it is actually 5 months long. 

Learning to Avoid Pain

On the journey to determine if a fish feels pain or not, scientists tried to see how a fish reacts to pain-relieving chemicals. They raised the temperature, and the fish reacted to that painful stimulation. After injecting it with morphine, they could bear the heat. But, when the scientists increased the heat a bit more, the fish began to feel pain.

There are other experiments that prove fishes react to pain and morphine like us. After being put through a painful event, the fish started breathing heavily. Then, it was given morphine to see if the fish would calm down. And, in the end result, it did calm down and began breathing normally.

Aside from the morphine, there is a theory that a fish has a natural pain-killer – opioid receptors. You might recall our discussion about them from earlier. So, these opioid receptors exist in fishes, and it helps reduce pain when they are exposed to anything that can cause pain.

How Does This Affect Fishers?

When you pluck a fish out of the water, it starts wriggling violently because it is not only suffocating, but it is also feeling pain. Can you imagine going through such an experience? The new evidence of the fact a fish suffers from pain, it should lead to the question: What are fishers doing to make this less painful?

Rather than leaving out to suffocate, I would urge you to find a better way to ease their pain. One of them is common practice in Japan, called Ike jime (read: spiking/pithing). Here is how you do it;

  1. Jab a thin spike into its brain.
  2. Cut the tail.
  3. Place the tail below the end of the fish to reveal the spinal cord.
  4. Slip a wire through the spinal cord.

Another method of killing a fish humanely is called percussive stunning. This is a bit gruesome compared to ike jime, but it is quick and effective. Find a heavy object and smash it right between their eyes. Do it twice just in case the fish survives the first blow.

Aside from these two methods, I would recommend avoiding the following methods used to kill a fish;

  • Resting them on ice
  • Using carbon dioxide in water
  • Salt or ammonia bath
  • Suffocation
  • Bleeding out

By using methods like ike jime, you might even get a fish that tastes far better. We have to start adjusting to this new reality so that a fish doesn’t feel pain as extremely as it currently does.

The Big Picture

By little success, perhaps, this will inspire a couple of fishermen to start killing fishes more humanely, but who will stop the large fisheries? The Animal Welfare Act and the Humane Methods of Slaughter Act will need to be amended. These two legal policies basically determine how a fish should be treated.

Realistically, it will be a bit difficult to use ike jime to kill every single fish. When a large fishery gets a catch, there is not one, but thousands of fishes. Their problem is understandable, but the need to kill humanely is still there. What do we do?

We could use equipment like a pneumatic piston. Out in the Atlantic ocean, a group called Freshwater uses this equipment to kill fish, and it takes them about 15 seconds to kill every fish. It’s humane. For fishes that have the ability to survive this, another company called Engle-stone uses electric stunning to kill a fish.

Aside from the fact this is a humane way of killing fishes, the fishes are of better quality compared to the latter. It is an efficient and effective way of killing fishes.

Related Questions

Do fish feel pain when they get hooked?

Yes! Fish feel pain. Some scientists conducted an experiment where rainbow trouts were given an injection of acetic acid and found an interesting result. They found that a fish behaves defensively because of the pain. Interestingly, it won’t feel pain on the surface because it doesn’t have any brainpower at that point.

Do fish feel pain when you clean them?

A wriggling fish on the hook is unaffected because it doesn’t have the brainpower to feel any pain. Some experiments also theorize that just because an animal has pain receptors, it doesn’t necessarily mean they feel pain. These receptors might exist to warn the animal of any possible threat.

Do fish suffer when they are dying?

Unfortunately, a fish does suffer in death. Often times, a fish would suffer in pain till it dies within a couple hours. About half of the fishes pulled out of water die at the site out of suffocation. The remaining group of fishes die at tournaments. They are at greater risk of dying in tournaments because they’re caught repeatedly within the same day.

Related Articles

Other Sources

Leave a Comment