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Fish feel pain, they are self-aware, they remember, they build relationships and exhibit emotional responses. Deliberately inflicting pain and suffering on these animals is inexcusable.

Find out more about the science behind fish sentience.

Fish sentience: The science

There are over 1 million registered recreational fishers in NSW (1) and it has been claimed the economic, physical and mental benefits make recreational fishing of major importance to the state’s economic and social welfare.

We have all seen the idyllic scenes of a family bonding in a boat or on a riverbank as they angle for fish, or those of mates out in a tinny for a day, further cementing their friendship as they mix conviviality and cunning to “bag a big one”. 

While fishing may project this wholesome image, little or no thought is given to the billions of fish whose suffering, which is central to a “top day on the water”, lies below the surface, out of sight and out of mind.

While the pain inflicted on a fish may not be paramount in the mind of any fisher it has been found most fish possess highly developed sense organs and are able to orient themselves using landmarks and other signals while fish behaviour in mazes reveals that they possess spatial memory and visual discrimination.(2)


For centuries, fish have been thought to be insensitive to pain. Their deaths via suffocation, maceration, spearing, live gutting, decapitation or blows to the head were of no concern as fish were regarded as “cold-blooded creatures”, devoid of feeling pain. It was argued fish brains were different from mammalian brains as they lacked a neocortex, so were incapable of receiving pain stimuli. This fallacious line of thought was debunked by Professor John Webster, of the University of Bristol, who stated, “to say that a fish cannot feel pain because it doesn’t have a neocortex is like saying it cannot breathe because it doesn’t have lungs”.(3)

Professor Webster is one of many researchers who have come to the conclusion that fish not only feel pain but have complex societies, can learn and remember, engage in critical thought and empathise.

In her book, “Do Fish Feel Pain?”(4), Dr Victoria Braithwaite cites the growing body of science that finds fish are far smarter than previously thought and have accurate and long lasting memories, as in the case of long-distance migrating salmon.

For those with a more advanced scientific understanding, the European Food Safety Authority Animal Health and Welfare (AHAW) report (5) lists some of the criteria used to indicate whether an animal, including fish, might be capable of experiencing pain. It goes on to gives some examples of evidence supporting each of these in fish species:

  1. the existence of functional nociceptors
  2. the presence and action of endogenous opioids and opioid receptors
  3. the activation of brain structures involved in pain processing
  4. the existence of pathways leading to higher brain structures
  5. the action of analgesics in reducing nociceptive responses
  6. the occurrence of avoidance learning
  7. the suspension of normal behaviour associated with a noxious stimulus

This report led to the European Union in 2005 including fish in its list of sentient beings and enacting its “Five Freedoms”:

  • Freedom from hunger and thirst
  • Freedom from discomfort
  • Freedom from pain, injury and disease
  • Freedom to express normal behaviour
  • Freedom from fear and distress (6)


Going beyond the distressing notion of the pain inflicted on billions of fish annually, scientists have discovered fish possess many qualities thought only to reside with more evolved species. Culum Brown, Associate Professor, Macquarie University, stated  “In many areas, such as memory, their (fish) cognitive powers match or exceed those of ‘higher’ vertebrates, including non-human primates. Best of all, given the central place memory plays in intelligence and social structures, fish not only recognize individuals but can also keep track of complex social relationships.” (7)

Professor Brown cites the many fish which build nests for rearing young, similar to birds, while others have permanent burrows or preferred hiding spots. He relates the constant challenge for the rock-moving wrasse which have to build a new home each night by collecting rubble from the ocean floor.  This use of tools, which is supposed to belong only to higher order creatures, may be found in other fish who use tools for foraging, rocks for crushing sea urchins, or the archerfish who shoot water to capture insects, to the deep-sea lantern fish which produce fluorescent photophores to capture prey.

Other species of grazing fish display an agricultural inclination where they tend their underwater gardens by constantly removing unwanted algae and encouraging the growth of more preferred species.

Some fish engage in symbiotic relationships to maintain their food supply and/or provide protection. Those who have watched the popular movie “Finding Nemo” will be familiar with the bond between the clown fish and the sea anemone. The clown fish, immune to the anemone’s venom attracts predators who are caught in the venomous entrails of the anemone, which then consumes its prey, leaving some scraps for the clown fish. 

Another species of fish which relies on mutualism to survive is the cleaner wrasse. Its food supply is the dead bits of skin and parasites from the bodies of other fish which the wrasse removes with the utmost care because a careless nip will see the loss of a customer. One way the chastened wrasse will lure back a lost client is through a caressing back rub. Hardly the action of an insensitive and unconscious organism.

Further evidence of the sentient nature of fish has been found in studies conducted to determine whether fish are capable of learning. (8 & 9) Through electric shock and reward stimuli it has been shown fish will stay away from parts of their aquarium where they received an electric shock and taught to respond to stimuli such as sound and light for the reward of food. One study that reduced the reward to only one hour a day found the fish remembered this time and only engaged in the reward-producing behaviour when they knew food was forthcoming.

These examples are just a few of the discoveries that demonstrate fish are feeling, aware and alert creatures.

The aforementioned “Finding Nemo” may have appealed as a sentimental family film but its underlying philosophy of fish sentience is one we need to acknowledge.

Fish may not have many opportunities to ingratiate themselves into human hearts as dogs or cats do but we should be under no illusion that their lack of a voice, a wagging tail or soft coat does not mean they lack the ability to think, feel and act. To quote a line from Ian McEwan’s novel “Saturday”, It is a good thing that sea creatures have no voice, otherwise there’d be howling from those crates.” (10)


  1. NSW Dept. of Primary Industries -
  2. Journal of Undergraduate Life Sciences. "Appropriate maze methodology to study learning in fish"
  3. Webster, J. 2009. Concepts in Animal Welfare. 1. Sentience and Suffering: Why animal welfare matters. University of Bristol School of Veterinary Science, Bristol, UK.)
  4. Braithwaite, V. 2010. “Do Fish Feel Pain?” Oxford University Press, USA, 2010 ISBN13: 9780199551200
  5. European Food Safety Authority.
  6. European Union -
  7. Culum Brown (Associate Professor, Macquarie University), Not Just a Pretty Face, New Scientist, June 12, 2004
  8. Dunlop, Rebecca et al. "Avoidance Learning in Goldfish (Carassius auratus) and Trout (Oncorhynchus mykiss) and Implications for Pain Perception." Applied Animal Behaviour Science. May 2006. (Oct. 16, 2014)
  9. Highfield, Roger. "Painful Memories for Goldfish." The Telegraph. Jan. 31, 2006. (Oct. 16, 2014)
  10. 10.McEwan, I. “Saturday”. Anchor Publishing 2005. ISBN13: 9781400076192

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