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Fish Smarts: Why Fish Are More Than Just Streams of Protein

Fish are smart, sentient, and know a lot about themselves and others

I'm always looking for interesting and "surprising" discoveries about animal cognition and emotions to share with readers and today I learned about two excellent and brief summaries of some of the latest news about the cognitive lives of fish -- what they know about themselves and others. In the past I've written a lot about fish sentience because fish often get the short end of the stick when people write about the cognitive and emotional lives of vertebrates (please also see "Fish have feelings too: Expert claims creatures experience pain in the same way humans do - and should be treated better" in which it is noted, "Fish have good memories, build complicated structures and show behaviour seen in primates - as well as feeling pain like us"). Indeed, fish were omitted from the list of animals mentioned in the Cambridge Declaration on Consciousness, issued in July 2012 (please see "Scientists Finally Conclude Nonhuman Animals Are Conscious Beings") when they should have been included. At the time the declaration was issued we knew a lot about fish sentience and cognition and their omission is regrettable and indefensible..

An excellent review of research on fish cognition and emotions can be found in Macquarie University's Culum Brown's essay called "Fish intelligence, sentience and ethics," published in the peer reviewed journal Animal Cognition. A very interesting and important interview with Dr. Brown by Farm Sanctuary's Bruce Freidrich can be read here.

The abstract for Dr. Brown's essay reads as follows: Fish are one of the most highly utilised vertebrate taxa by humans; they are harvested from wild stocks as part of global fishing industries, grown under intensive aquaculture conditions, are the most common pet and are widely used for scientific research. But fish are seldom afforded the same level of compassion or welfare as warm-blooded vertebrates. Part of the problem is the large gap between people’s perception of fish intelligence and the scientific reality. This is an important issue because public perception guides government policy. The perception of an animal’s intelligence often drives our decision whether or not to include them in our moral circle. From a welfare perspective, most researchers would suggest that if an animal is sentient, then it can most likely suffer and should therefore be offered some form of formal protection. There has been a debate about fish welfare for decades which centres on the question of whether they are sentient or conscious. The implications for affording the same level of protection to fish as other vertebrates are great, not least because of fishing-related industries. Here, I review the current state of knowledge of fish cognition starting with their sensory perception and moving on to cognition. The review reveals that fish perception and cognitive abilities often match or exceed other vertebrates. A review of the evidence for pain perception strongly suggests that fish experience pain in a manner similar to the rest of the vertebrates. Although scientists cannot provide a definitive answer on the level of consciousness for any non-human vertebrate, the extensive evidence of fish behavioural and cognitive sophistication and pain perception suggests that best practice would be to lend fish the same level of protection as any other vertebrate.

This weekend I learned about an essay by Abigail Geer called "5 Incredible Fish Behaviors That Show Just How Intelligent They Really Are" that nicely summarizes some of the latest research on fish cognition. Ms. Geer writes about mutual cooperation, how fish cheat others, how they form hunting partnerships, how they signal to others using their body, and how they know to eat food that will disappear shortly. She concludes her essay as follows: "As humans, we have developed a very self centric view of the world, where we judge all other species by our own perception of them. For us to develop into a more compassionate society, which is not responsible for the murder of billions of animals each year, we must learn to understand and respect each and every animal on the planet for who they are."

Primates aren't all that special

Ms. Geer's essay is based mainly on the work of noted fish researcher Redouan Bshary, who's groundbreaking research is summarized in an essay by Alison Abbott called "Animal behaviour: Inside the cunning, caring and greedy minds of fish" published in the prestigious journal Nature. Both Ms. Geer and Ms. Abbott's essays are easy reads and I highly suggest them. Research on the cognitive and emotional lives of fish are showing that non-human primates aren't all that special. Emory University's world renowned primate researcher Frans de Waal notes, “Primate chauvinism may now be poised to decline, thanks in large part to Bshary's fish work." Claims about nonhuman primate and human exceptionalism must be carefully re-evaluated because this sort of speciesism can be seriously called into question based on solid scientific research.

Fish should be included in our moral circle

So, what does the latest research on fish cognition and emotions mean in terms of how we treat them? In her very interesting book called Do Fish Feel Pain? Victoria Braithwaite concluded, "I have argued that there is as much evidence that fish feel pain and suffer as there is for birds and mammals — and more than there is for human neonates and preterm babies." (page 153).

It's high time that we use what we know on behalf of fish and other animals who are used and abused in the countless billions. Fish clearly are not things nor disposable objects or mere streams of protein, but rather sentient and feeling beings, a point stressed in Farm Sanctuary's “Someone, Not Something” project.

In a recent interview with Hope Ferdowsian I noted, "There still is a lot of work to be done but there is no doubt in my mind and heart that we can make the world a much better place – a more compassionate home — for nonhumans and humans. It isn’t going to be easy but that’s just the way it is. Every one who can do something positive must do what she/he can do. We need to be activists, not slacktivists. We all must walk the talk and not expect others to do what we can and should do. I remain optimistic because of all the wonderful people who are out there working for all animals and their homes. We must remember that compassion begets compassion and violence begets violence. I love the saying, 'The world becomes what you teach,' espoused by the Institute for Humane Education.”

It is essential that a broad audience knows what we are learning about fish from detailed empirical research. As noted above, Dr. Brown concludes his essay as follows: "Although scientists cannot provide a definitive answer on the level of consciousness for any non-human vertebrate, the extensive evidence of fish behavioural and cognitive sophistication and pain perception suggests that best practice would be to lend fish the same level of protection as any other vertebrate." I couldn't agree more. Fish and all other animals need all the help they can get and we need to use what we learn from empirical research on their behalf.

Note: I just learned of a most valuable essay by B. Wren Patton and Victoria Braithwaite called "Changing tides: ecological and historical perspectives on fish cognition," the abstract of which concludes, "Never before has the field had such a wide array of interdisciplinary techniques available to access both cognitive and mechanistic processes underpinning fish behavior. This capacity comes at a critical time to predict and manage fish populations in an era of unprecedented global change." You can also watch an interview with Dr. Braithwaite here about why fish need to be treated humanely.

Marc Bekoff's latest books are Jasper's story: Saving moon bears (with Jill Robinson), Ignoring nature no more: The case for compassionate conservation, Why dogs hump and bees get depressed, and Rewilding our hearts: Building pathways of compassion and coexistence. The Jane effect: Celebrating Jane Goodall (edited with Dale Peterson) has recently been published. (; @MarcBekoff)