The last cast

Myriad Misunderstandings about Fish - and Beliefs that are Dead Wrong
by Dr. John G. Nickum

We did not receive any questions that we could use in time for this issue of the High Country Angler, so the “Old Professor” is going to take off on a subject near and dear to him: conceptions and misconceptions about fish.

Many people have some pretty weird ideas about fish. It seems to be very difficult for them to understand that life in an aquatic environment is different; very different from life on land. It takes very different adaptations to survive, grow, and reproduce in water, compared to those required on land. The oxygen supply is much lower, the temperature range is smaller, movement in a fluid is more difficult, vision is reduced, living in a “chemical soup” is different, being surrounded by your own waste products is very different, and leaving your embryos to survive on their own certainly is different. Nevertheless, fish do survive. They have many adaptations that make survival possible. When we fail to recognize the myriad differences between fish and us, between their world and ours, we jeopardize the very survival of these animals; animals that provide so much sustenance and enjoyment. We need to understand fish as they are, not as some folks want them to be, or wish to believe they are. We share certain vertebrate characteristics with fish, but just as we lack many fish adaptations, fish lack many human adaptations.

One of the most obvious misunderstandings about fish comes from the animal rights movement, especially People for the Ethical Treatment of Animals (PETA). PETA has a new campaign under way that claims that fish are sensitive animals and as intelligent as pet dogs and cats. PETA also claims that “fishing hurts”. Scientifically valid research has thoroughly discredited these claims. A hooked fish is trying to escape. It is not reacting to pain. Fish are sensitive?? The reality is that fish eat each other and even eat their own young. They do have wonderful sensory capabilities that enable them to survive in a hostile environment where even a momentary lapse causes them to be food for another fish or some other animal. Fish are intelligent?? The form of learning demonstrated by fish is very rudimentary; similar to something that used to be called “conditioned behavior”. Such “learning” is considerably less advanced than the learning of their terrestrial relatives. Fish feel pain?? No, fish just do not feel pain. In their world, pain would be counter-productive and hinder their survival. They do have wonderful sensory capabilities that enable them to avoid harmful situations, but they lack the brain structure required for consciousness and the experience of pain. Even humans do not feel pain when these essential brain sections have been destroyed, nor when we are anesthetized. These essential brain parts are just not present in fish. PETA and the animal rights folks operate within a belief system that has no scientifically valid support. We must recognize PETA’s claims for what they are; personal, quasi-religious beliefs – beliefs that they would impose on all of us.

However, the animal rights folks are not the only ones who have failed to “get real” about fish and their needs. Those who exploit our water resources and focus only on the personal benefits that they can derive from these resources, frequently ignore the effects of their actions on the fish. I'm not sure if these people don’t know or don’t care about the problems they cause, but the effects on the fish are very real. These extreme exploiters also show a callous disregard for the interests of other humans. We all have an interest in maintaining our water resources in quantities and qualities that allow fish to survive and prosper.

Fish are not adapted for survival in de-watered streams, nor in heavily polluted waters. They do not survive or perish based on average conditions. It’s the extreme conditions that count in the aquatic world. Each type of fish has a range of tolerance for an array of environmental factors and a smaller range of conditions in which they can prosper. Averages don’t mean much to a fish. An average water temperature of 55o F seems pretty good for trout, but if that average includes even one day when the water temperature hit 85o, the trout are dead and the average is meaningless. Likewise, an average dissolved oxygen content of 10 ppm does no good if it includes a couple of hours when there was no dissolved oxygen in the water. A two hour exposure to toxic levels of chemical pollutants kills fish, no matter what the long-term average may be. Average instream flow is yet another matter where fish have specific requirements. If the flow falls below minimum levels, the fish cannot pack up and move to the next stream, hide under a rock, nor burrow into the mud to survive until everything returns to normal. It’s the extremes, not the averages that count for fish.

Even concerned anglers who fight for high quality aquatic environments, fail reality tests sometimes. When an angler hooks and nets the “big one” and keeps it out of the water for 5 – 6 minutes while everyone admires the fish and takes pictures, that fish is severely stressed. Yes, the fish may swim away when released, but are these anglers aware of delayed stress reactions? It is common for fish to show a delayed response 48 to 72 hours after severe stress. They become lethargic and do not respond normally to potentially harmful stimuli. Such behavior is usually fatal in the harsh world of fish.

All of us must “get real” about fish if we are to continue to enjoy them, the recreation they provide, and the food they provide for billions of people. Learn about them. Learn about their unique adaptations and requirements. And never assume that they are just like us. Give fish a chance to be fish and appreciate them for what they are. It’s time to get real!
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If you have a question for the Old Professor, send it to “Trout Talk” c/o Colorado Trout Unlimited, 1320 Pearl Street, Suite 320, Boulder, CO 80302. If your question is used in a future issue of High Country Angler, we’ll send you a long-billed CTU cap.