Do Fish Have Feelings? 12 Scientifically Discovered Emotions

HIGHLIGHTS

  • Fish do have Feelings because they have a brain that resembles the human brain.
  • Fish have feelings of pain, anxiety, sadness, empathy, stress, fear, anger, love, grief and joy. Fish form friendships.
  • Goldfish and betta fish are common breeds that have feelings. While the extent of feelings in jellyfish is not known.

For centuries, humans have been fascinated by the inner lives of animals. What do they think? Do they feel pain? What goes on inside their heads?

We’re still learning the answers to these questions, but scientists have made some progress when it comes to understanding the emotions of fish. Fish are often seen as simple creatures, but the truth is that they are complex and interesting animals. One question that people often ask is “do fish have feelings?”

In past, it was difficult to answer because there was no scientific research on it. Now, there is a lot of research that can help us understand whether fish have the capacity for emotions.

Read on to find out what scientists have discovered.

Jonathan Balcombe in his book, What A Fish Knows: The Inner Lives Of Our Underwater Cousins, writes:

In many ways, the cognitive capabilities of fish rival those of mammals. Given what we know about the neurological underpinnings of consciousness and emotion in other animals, it seems likely that fish have these experiences as well.

Do Fish Have Feelings? Scientific Researches Prove They Do

The feelings and emotions in a creature are controlled by the brain. So, here a question arises “do fish have brains?”

And if they have what is the level of complexity of their brain? Do they have brain parts that control feelings or not?

Let’s find the answer to this question first.

Do Fish Have A Brain? The Complexity of Fish Brain

Yes, fish have brains. Fish have a central nervous system that is similar in structure to the human brain.

They have a cerebral cortex, which is the part of the brain responsible for processing information and controlling muscle movement. This suggests that fish are able to think and move in purposeful ways.

Sonia Rey Planellas from the Institute of Aquaculture, Faculty of the Natural Sciences University of Stirling, UK discusses the complexity and similarity of fish’s brain with humans in her article “The emotional brain of fish Commentary on Woodruff on Fish feel

According to her, fish have dorsomedial and dorsolateral telencephalic pallium that is similar in function to mammalian amygdalae. This structure is responsible for processing emotions in fish.

fish do have brain and so have emotions
Pic Credit Awesomeocean.com

This suggests that fish are capable of experiencing emotions such as fear, anxiety, anger, and happiness.

The more complex the brain, the more emotions it can experience.

Fish have very complex brains for their size. In fact, they have a three-chambered heart and a network of nerves that is similar to humans.

According to neuroscientists, fish are capable of experiencing pain, anxiety, stress, and fear.

They also have a very good memory. These qualities are all controlled by the brain, which means that fish are capable of feeling these emotions.

In addition, fish have neurotransmitters such as dopamine and serotonin in their brains that play a role in mood and stress management.

For example, serotonin is a neurotransmitter that has been linked to positive feelings such as happiness and relaxation.

The hypothalamus in fish is responsible for the production of endorphins which are natural painkillers. Also, like in mammals, fish have opioids in their brains which work to reduce the sensation of pain.

Some fish also have a structure called the pineal gland, which is thought to be involved in regulating sleep and wakefulness.

The lateral line system of sensory organs is present in fish and some other aquatic animals. The lateral line is used to detect vibrations and changes in water pressure. This information is used by fish to navigate and avoid predators.

The lateral line is also used to detect prey. When a fish detects the vibrations of a nearby fish, it will swim toward the prey and consume it.

In fish mechanoreceptors which are pressure-sensitive receptors, are present in the skin of fishes. These receptors respond to physical stimuli such as touch, vibration, and changes in water pressure.

Fish also have temperature-sensitive receptors in their skin that help them to detect changes in water temperature. These receptors help fish to regulate their body temperature and avoid predators.

Chemoreceptors are also present in the skin of fishes. These receptors respond to chemical stimuli such as toxins and changes in water pH. Chemoreceptors help fish avoid predators and find food.

The lateral line is also used to detect prey. When a fish detects the vibrations of a nearby fish, it will swim toward the prey and consume it.

While fish don’t have emotions in the same way that humans do, they are still able to feel pain, anger, sadness, taste, and touch. This allows them to survive in their environment and avoid predators.

So, we can say that fish have developed nervous systems and some of them even have parts that control emotions. Now let’s see the scientific studies that have been conducted about the emotions of fish.

Do Fish Have Feelings? Behavioral Study Suggest So

Researchers have observed certain behaviors in fish that suggest they may experience positive and negative emotions.

For example, clownfish will form close bonds with other members of their group and will defend their territory aggressively if necessary.

When clownfish are separated from their bonded group members, they will become stressed and may stop eating altogether. This shows that clownfish form close attachments to others and experience negative emotions when those attachments are threatened.

Fish can get aggressive - do fish have feelings

In addition, goldfish have been known to show signs of boredom when they are kept in tanks with little to no stimulation. Goldfish kept in boring tanks will often chew on the sides of their tank or swim aimlessly back and forth.

When given toys or other objects to interact with, goldfish will show more interest in their environment and exhibit fewer signs of boredom. This suggests that goldfish experience positive emotions when they are given stimulating environments to explore.

In one study, researchers found that fish responded to both positive and negative reinforcement. This shows that they are able to learn from both their successes and failures. The fact that they can remember this information,

One study found that fish react to being touched in a similar way to humans. When they were touched in a gentle way, they became more social.

However, when they were touched in a rough way, they became more aggressive. This suggests that fish may be able to experience both positive and negative emotions.

Another study looked at the brain activity of fish when they were exposed to stressful situations. The researchers found that the fish had increased levels of cortisol, which is a stress hormone. This suggests that fish do experience stress, which is an emotion.

So, what do we know for sure? There is various evidence that suggests that they may be capable of experiencing a range of positive and negative emotions. This means that we should treat them with care and respect, as we would any other animal.

It is now obvious that fish do have feelings. Another question arises what emotions and feelings do fish have? Now, we’ll discuss all the emotions that fish have.

Emotions That Fish Have

Fish Can Experience Fear and Anxiety

It’s long been assumed that fish are incapable of experiencing fear or anxiety because they lack a cerebral cortex—the part of the brain responsible for these emotions in mammals.

However, recently various researchers have shown now that this is not the case. In a study published in 2016, scientists found that fish react to stressful situations in much the same way as mammals do.

When exposed to predators or other threats, fish release cortisol—a stress hormone—into their bloodstreams. The cortisol levels remained elevated even when the threat had passed, which suggests that fish may experience fear and anxiety in similar ways to mammals.

fish have feelings of fear which means fish do have feelings

Fish Feel Pain – Scientific Studies Reveal so

Do you think that fish feel pain? Scientists aren’t sure, but there’s some evidence to suggest that they might.

It’s long been assumed that fish do not feel pain because they lack a cerebral cortex—the part of the brain responsible for processing pain signals.

However, recent research has shown that this may not be the case. In a study published in 2015, scientists found that fish react to painful stimuli in much the same way as mammals do.

Pain receptors in Fish

When exposed to a painful stimulus, fish release cortisol—a stress hormone—into their bloodstreams. The cortisol levels remained elevated even when the pain had passed, which suggests that fish may experience pain in similar ways to mammals.

In addition, the researchers found that fish have specialized nerve fibers called nociceptors, which are responsible for sending pain signals to the brain. This means that fish likely have the ability to feel pain, just like mammals do.

In a 2008 study, for example, scientists found that fish responded to a painful stimulus by rubbing their bodies against objects in their tanks—just as mammals do when they’re in pain. 

Pain receptors in fish are present so fish do feel pain

Other studies have shown that fish exhibit stress-related behaviors when they’re exposed to stressful situations.

For example, a 2007 study found that fish became more sluggish and stop feeding as much when they were exposed to high levels of carbon dioxide. In addition, many fish will rub their bodies against objects in their environment when they are injured.

So, it is now clear that fish do feel pain. This means that we need to be careful when handling them and make sure not to cause them any unnecessary pain.

Fish have memory & Remember Previous Experiences

It’s well-known that mammals can remember previous experiences and learn from them. What’s less well-known is that fish are also capable of this type of learning.

In a study, scientists found that zebrafish were able to remember a painful experience and respond accordingly when they were exposed to it again. The researchers believe that this memory lasts for 10 days—a relatively long time considering the size of a fish’s brain.

This ability to recall previous experiences and learn from them is yet another indication that fish are capable of complex emotional responses.

Do Fish Feel Sadness? Yes They Do

Yes, fish can feel sadness.  According to a study published by the Journal of Agricultural and Environmental Ethics, fish do feel sadness.

The study found that when fish are separated from their group or their partner, they show signs of depression similar to those seen in humans.

A study published by American Psychological Association by placing two zebrafish in separate tanks and then monitored their behavior. When the fish were placed together, they swam around happily and interacted with each other.

However, when they were separated, the zebrafish became inactive. When they stopped interacting with each other, they also displayed signs of depression, such as decreased appetite and lack of interest in food.

Separation anxiety in fish is observed - fish do feel stress

These findings suggest that fish do feel sadness and can experience negative emotions when separated from their group or partner. This information could be used to help improve the welfare of fish in captivity.

Do Fish Feel Angry? Fish Feel Aggressiveness

It’s well-known that many animals, including mammals, feel aggressive and territorial emotions. What’s less well-known is that fish also experience these emotions.

In a 2021 study, for example, scientists found that fish become more aggressive when they are exposed to the chemical cues of other fish. This aggression was exhibited in both laboratory settings and in the wild.

In addition, many fish species are known to be territorial. They will defend their territories against intruders—sometimes even to the death.

This behavior is yet another indication that fish experience complex emotions such as aggression and territoriality.

Fish Feel Psychological Stress

Just like mammals, fish can experience psychological stress. In a 2010 study, for example, scientists found that clownfish became more aggressive when they were exposed to high levels of carbon dioxide.

The clownfish in the study showed signs of stress, such as increased aggression, when they were exposed to high levels of carbon dioxide. This suggests that fish are sensitive to changes in their environment and can suffer from psychological stress as a result.

In addition, a study published in the Journal of Science of The Total Environment found that fish become more anxious and less social when they’re kept in tanks that are too small.

This suggests that fish need space to feel comfortable and that crowded environments can cause them stress.

Fish can be stressful due to environmental changes

Taken together, these studies show that fish are capable of feeling a wide range of emotions, from happiness and excitement to fear, anxiety, and stress.

This means that we need to be careful when handling them and make sure not to cause them any unnecessary stress or discomfort.

Fish Feel Love, Grief, and Joy

In addition to pain and stress, fish are also capable of experiencing positive emotions, such as love, joy, and grief.

Fish become attached to their owners and prefer the smell of their owner’s skin over the smell of strangers.

In addition, many fish forms close bonds with other fish and show signs of distress when they’re separated from them. For example, clownfish will often die of grief if their partner dies.

And finally, fish also have the ability to experience joy. Fish become more active and playful when they listen and enjoy music.

Fish can feel happiness

These studies show that fish are far more complex and sensitive creatures than most people realize. This means that we need to be careful when handling them and make sure not to cause them any unnecessary stress or discomfort.

Fish Show Signs of Empathy Towards Other Fish

Empathy is the ability to understand and share the feelings of another living creature. Scientists have found evidence that fish are capable of empathy by studying their interactions with other fish in distress.

Scientists placed one group of cichlid fish in a tank with an electric current running through it (this caused the fish to display signs of stress).

They then placed another group of cichlid fish in a separate tank where they could see and hear their stressed-out tank mates but weren’t themselves exposed to the electric current.

The second group of fish responded by displaying stress-related behaviors of their own—suggesting that they were empathizing with the distressed fish in the other tank.

Fish Form Close Social Bonds – Friendship in Fish

Just like mammals, some species of fish form close social bonds with one another.

These bonds are often formed between members of the same species (such as between two male guppies).

Fish form social bonds and friendship with other fish

But they can also form friendships between members of different species (such as between a clownfish and its host sea anemone). These bonds are thought to be beneficial for both parties involved.

For example, studies have shown that social bonds can reduce stress levels and improve reproduction rates in clownfish.

Feelings in Different Breeds

Some breeds of fish are known to experience a wider range of emotions than others. Here are some breeds of fish that feel things differently than other fish.

Do Goldfish have feelings? Certainly, They Do

Goldfish are a very popular type of pet fish. They are known for being friendly and easy to care for. But do goldfish have feelings? Yes, they certainly do.

They are often thought of as being one of the more emotional fish breeds due to their ability to express a variety of different feelings.

Some of the emotions that goldfish have been known to experience include happiness, sadness, fear, anger, and love.

Goldfish are able to express these emotions in a variety of ways. When happy, goldfish have been known to swim faster and use their fins more.

When sad or scared, goldfish tend to hide and may stop eating. And when angry, goldfish may become aggressive and attack other fish.

Goldfish and betta fish do have feelings

Do betta fish have feelings? Yes They Do

Betta fish are a popular type of pet fish known for their bright colors and beautiful fins. But do betta fish have feelings? The answer is yes, betta fish certainly do have feelings.

Betta fish are able to experience a wide range of emotions, just like goldfish. Some of the emotions that bettas have been known to experience include happiness, sadness, fear, anger, and love.

Like goldfish, betta fish express these emotions in different ways. Happy bettas swim faster and flare their fins. While anxious or scared bettas hide and don’t eat. Bettas are aggressive and territorial fish. It attacks other fish when angry.

Do Jelly Fish Have Feelings? Primitive Nervous System

In Jellyfish, the brain is not centralized so they don’t have a nervous system like humans which helps to process and feel emotions.

So, they don’t have emotions because they don’t have a brain. Jellyfish still have a primitive nervous system that allows them to sense their environment and respond to stimuli.

Jellyfish are able to sense touch, light, temperature, and the presence of other animals around them. They use this information to help them survive in their environment.

For example, if a jellyfish senses that it is being touched, it will often times sting the creature that is touching it. This allows the jellyfish to protect itself from predators.

While jellyfish don’t have emotions in the same way that humans do, they are still fascinating creatures that are worth learning about.

Do fish have feelings in their mouth?

Yes, fish have feelings in their mouth. According to research, fish have many pain receptors (nociceptors) in their mouth. So when they get hurt, they feel pain just like we do.

Fish also have a sense of taste due to taste buds in the mouth. They use their sense of taste to help them determine if something is safe to eat or not.

If a fish tastes something that is poisonous, it will often times spit it out. This helps the fish to avoid eating something that could hurt them.

While fish don’t have emotions in the same way that humans do, they are still able to feel pain, taste, and touch. This allows them to survive in their environment and avoid predators.

Do Fish Have Feelings? Scientifically They Do

Conclusion 

So, Do Fish Have Feelings? Scientists have only just begun to unlock the secrets of animal emotions, but what they’ve discovered so far indicates that fish are more emotionally complex than we once thought.

They can experience fear and anxiety, learn from past experiences, show signs of empathy towards others, and form close social bonds with those around them. In short, there’s plenty of evidence to suggest that fish do have feelings—and plenty more still to be discovered.

If you have a pet fish, be sure to provide them with an enriching environment so it can experience positive emotions.

What opinion do you have about the feelings of fish? Let us know in the comments.

References

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Author

  • Frank R. Snow

    Frank R. Snow has two hobbies. First, aquarium fish keeping while writing is the second. He has been an aquarist for the past nine years; therefore, his love for fish is extraordinary. He shares the fish’s feelings. So, together we will make the life of our underwater friends easy.

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