Meet the Animals: Fish

Fish Behavior, Emotion, and Intelligence

  • “In many areas, such as memory, their cognitive powers match or exceed those of ‘higher’ vertebrates, including non-human primates.” — Professor Culum Brown, Macquarie University

Fish are Friends, Not Food

The science on fish sentience is extensive, and it all points in one direction: Fish are individuals who are similar — emotionally, cognitively, and behaviorally — to land animals. While they don’t scream out in pain, they do feel pain. And, while most of us don’t get to know them because they spend all their time in the water, those who do know them respect them as individuals. Writing in New Scientist, Professor Culum Brown explains: “In many areas, such as memory, their 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.”¹

(c) chinahbzyg 2012, used under license from Shutterstock.

Marine biologist Sylvia Earle sums up her thoughts on fish this way: “I never eat anyone I know personally. I wouldn’t deliberately eat a grouper any more than I’d eat a cocker spaniel. They’re so good-natured, so curious. You know, fish are sensitive, they have personalities, they hurt when they’re wounded.”²

The BBC, in describing an article in the scientific journal Fish and Fisheries that discusses the knowledge gained based on more than 500 studies, explains that fish are “now seen as highly intelligent creatures…steeped in social intelligence…exhibiting stable cultural traditions, and co-operating to inspect predators and catch food. Recent research had shown that fish recognised individual ‘shoal mates,’ social prestige, and even tracked relationships. Scientists had also observed them using tools, building complex nests, and exhibiting long-term memories.”³ Fish, say the scientists, “can even be favourably compared to non-human primates.”


The journal article has been turned into a book, Fish Cognition and Behavior, which sums up the science: “Fishes exhibit a rich array of sophisticated behavior with impressive learning capabilities entirely comparable with those of mammals and other terrestrial animals.”4

In an interview with Australian Broadcasting Corporation’s “Counterpoint” program, Professor Brown explains one observational experiment in which fish learned how to escape a trawl net after just five exposures (15 minutes) and retained the knowledge for their entire lives. They also learn to avoid fishing vessels and hooked lines — though, as he points out, “we now use satellite technology and goodness knows what else to pinpoint them, so I think we still have the upper hand.”

He also discussed how fish “learn by observing or interacting with other fish,” which shows that fish have culture.5 And, on the issue of fish feeling pain, Brown explains that fish “feel pain in ‘exactly the same way we do.’” When they’re pulled out of the water, they experience stress such that their stress hormones are “exactly the same as a person drowning,” except that the fish experience this agony for 20 to 30 minutes.6


Fish are interesting and intelligent animals; they belong in their natural habitats, not in tanks or on dinner plates. For the same reason that we would never cram dogs or cats into tiny cages for their entire lives with little mental or physical stimulation, we should not confine fish in tanks as though they were no more than artwork. And, because we would not eat dogs and cats, who are individuals with personalities and interests, we should similarly refuse to consume fish.

From “Fish Out of Water

PETA President Ingrid Newkirk tells the story of a fish her ex-husband had in a tank many years ago. The fish would swim to the top of the tank to meet him when he returned home. The fish “jumped and wagged his tail like a dog, lifting about a fifth of his body clean out of the water.” He “would gently scratch the fish’s back, the fish offering first one side of his body to be petted, then the other, making little waves with the swishing of his fins.” She writes: “The captive fish tried to make the best of what was otherwise a plain life. He cleaned rocks by rolling them about in his mouth, swam through the hair curlers fastened together to form a jungle gym, and tickled his back in the bubbles from the aerator. Once, he swam purposefully to the west end of the tank, seized a plastic plant in his tiny jaws, and dragged it back to his corner. The next day, when the man tidied the tank and put the plant back in its ‘place,’ the fish moved it again to the new spot he had chosen for it.

When the fish died, I found myself trying to imagine what his ancestral waters were like, where and how he had been captured or bred, and what on earth we were thinking of when we acquired him and robbed him of his little fish destiny. Sorry, old fellow. Truly.”

¹Brown, C. (2004). Not just a pretty face. New Scientist, 2451.
²Orenstein, P. (June 23, 1991). Champion of the deep. The New York Times Magazine. ³Scientists highlight fish intelligence. (Aug. 31, 2003). BBC News,
4Brown, C., Laland, K., & Krause, J. (2006). Fish Cognition and Behavior. Hoboken, NJ: Wiley-Blackwell, Back cover.
5Fish: Smarter than we might think. (March 1, 2010). Australian Broadcasting Corporation Counterpoint.
6Mornings with Margaret Throsby. (Feb. 8, 2011). Australian Broadcasting Corporation.