Did you say cold fish?

One aspect of my work that I enjoy the most is talking with aquarium owners, and one of the most enjoyable conversations ever is to share fish stories highlighting their behavior and responses.

Most aquarists will talk about their fish as if they have a personality. Let’s be clear, I am part of the ones that believe they do have one, and I have many “stories” to sustain my claim. It is definitely not as obvious to the non-hobbyist as a dog wagging its tail or rolling on its back or being playful or threatening, but the signs are easily recognizable to the hobbyist.

What I am most intrigued with is what is it exactly they see or feel? See, I can’t help but noticing than when someone else comes close to the aquarium, they don’t really have the same response than the one they have as soon as I open the door to the room where the aquarium is. I could say the same about my Kenya Coral, although it is less noticeable. But after returning from a two-week vacation, the Kenya looked shrunk and not healthy at all. Less than a week later, it was fully deployed, larger and healthier than it had been. Perhaps it did not receive the same care that it usually does. Perhaps …

We know quite a bit about fish sensory system. Most fish have similar eyes that those of terrestrial vertebrates with a more developed spherical lens, although we do not know how they see us through an aquarium, they do. Hearing is another important sensory system in most fish, with some having more than one organ (bone conduction) that help them transfer sounds to the inner ear such as bladder (carp) and lateral line (shark), so it is quite possible they might have an appreciation for the music you play. They can smell as well. Sharks are known for their ability to smell 1ppm of blood miles away. Olfactory senses is said to help some migratory species recognize their original habitat and some others to identify potential mates as to avoid same gene partners. Finally, some fish species have the ability to sense electric current (in the order of millivolt) and electromagnetic fields.

After this summarized view of fish sensory system, it is safe to say our little friends, even tank bred have the ability to sense their environment as well if not better than most terrestrial species, and therefore they probably have a good sense of who we are, not just the hand that feeds them. Having the tools does not mean their brain has the actual ability to translate what they sense into actual feelings, or does it?

Many years ago I went to visit friends in Tahiti, French Polynesia. My friend, Pierre, a Tahitian himself introduced me to some of his family members. As we were talking about the ocean, one of them asked me if I had ever killed a fish. Well, beside a couple of fish I caught with a line, no. He said “You don’t know the ocean if you have not killed a fish.” Why I asked? They laughed. The next day, I went on with a speargun. At first I did not make much of an effort to catch one. I was enjoying the view as usual, trying to touch or catch them with my bare hands. And when I noticed it was getting late, I went on to catch one. It took me one, perhaps two hours but I eventually killed one. Very quickly, in a matter of minutes, I started seeing blacktip sharks swimming around me, some getting a little bit too close. Then, one that seemed to be a different kind of shark faced me with its jaw wide opened, I spread my harms and legs to make myself as big as I could and screamed under water. The shark made a 180 degree turn and disappeared as quickly as it appeared. I left the fish behind and swam back. The next day, my friend’s cousins came to check in. And they laugh. People laugh a lot and about anything on tropical islands. One of them said to me. “See, now you’ve learned something. Right before the fish died, it cried. That’s what got the sharks’ attention.” He did not use scream or grunt, he said “cry”. That description stayed with me.

This event happened years after the experiments done by William Tavolga who provided evidence that fish have pain and fear responses. But I doubt my Tahitian friends had ever heard of his research and neither did I. They were speaking from experience as other islanders whose lives have become so interwoven with the Big Blue that they believe aquatic species can feel as much as they do. Another research conducted by the University of Edinburgh and the Roslin Institute pointed to similar conclusion. However, Professor James Rose disagreed on the basis that there is no proof that fish possess “conscious awareness, particularly a kind of awareness that is meaningfully like ours”. He later explained that since fish brains lack a neocortex, they couldn’t feel pain. A more recent assessment of available studies similarly concluded: “fish do not have the neuro-physiological capacity for a conscious awareness of pain.” It makes perfect sense that based on our scientific understanding we would reach such conclusion. However, I wonder if they do have other ways of feeling, whether it is pain or joy or as animal behaviorist Mary Temple Grandin put it: They could still have consciousness without a neocortex because “different species can use different brain structures and systems to handle the same functions.”

Here is the event that led me to strengthening my belief in “fish are warmer than what we think”. My wall-mounted aquarium broke down. It is L29xH18xW5 and holds 10g. So for the time being, I bought a new 10g (L20xH10xW11.5). I transferred everything, same sand, same live rocks, same water and same aquatic life. The other noticeable difference was the filtration system and pump, which provided a nice water flow in the wall-mounted, while the new aquarium had a Power filter Penguin 150. It took me three months to get the parts and fix the wall-mounted (mostly due to a lack of time on my part). So one could imagine that after three months, my little friends had gotten used to their new home. Well, I thought so.

Once I transferred everything back to its original home, my clown fish had this very unexpected response. They danced, for the all day and the next they danced. They always jiggle when they see me, and with more intensity when it’s feeding time. But there for two days they danced, raced the length of the aquarium for countless hours. Even the ever placid (actually shy) fire goby stayed in the open much longer enjoying the water flow. Besides the point that my fish seem to enjoy a four star hotel much more than a motel 6, their behavior leads me to believe that they actually have a sensory system that not only encompasses the attributes of any terrestrial vertebrates but also includes emotional reaction such as pain and joy.

I know that we might never prove scientifically that some animals have or express emotions similar to those of a mammal, but I am convinced that their senses go way beyond what science has been able to prove thus far.

Please, share with others your own stories.

Thank you!


Marc Thibault