Does it hurt a fish to be hooked?
Fish have numerous nociceptors in their mouths and thus getting hooked is certainly a painful experience for them.
Fish have nerves, just like cats, dogs, and humans, so they can feel pain. Hooked fish endure not only physical pain but also terror. When they're removed from their natural environment, they start to suffocate. Just imagine the horrible feeling you'd experience if you were trapped underwater.
First, behavioural responses to sensory stimuli must be distinguished from psychological experiences. Second, the cerebral cortex in humans is fundamental for the awareness of sensory stimuli. Third, fish lack a cerebral cortex or its homologue and hence cannot experience pain or fear.
Even though survival chances of deep hooked fish are much improved when the line is cut, the presence of the hook may not be completely benign, as studies have shown yellowfin bream which carry ingested hooks long term gained weight at slower rates than normal.
Researchers find that wild cleaner fishes can remember being caught up to 11 months after the fact, and actively try to avoid getting caught again.
Use a landing net. Landing nets reduce handling time, stress, and the potential for injury, especially for large fish that are difficult to manage. Large frames with shallow nets made of rubber or small, soft, knotless mesh are best.
“Fish do feel pain. It's likely different from what humans feel, but it is still a kind of pain.” At the anatomical level, fish have neurons known as nociceptors, which detect potential harm, such as high temperatures, intense pressure, and caustic chemicals.
Here is a news article I found on the topic: Worms on a Hook Don't Suffer? OSLO (Reuters) - Worms squirming on a fishhook feel no pain -- nor do lobsters and crabs cooked in boiling water, a scientific study funded by the Norwegian government has found.
Catching A Fish Lowers Its Chance of Survival
This is obviously true if you keep it, but it's true if you release it as well. The stress of being caught, the energy spent fighting, and the possible harm done during handling all contribute to a higher mortality rate in caught fish.
Fish out of water are unable to breathe, and they slowly suffocate and die. Just as drowning is painful for humans, this experience is most likely painful for fish. Compounds like cortisol—the hormone associated with stress—can significantly increase during periods when fish are out of water.
What animal has the highest pain tolerance?
The naked mole-rat is impervious to certain kinds of pain. It's not alone | NOVA | PBS.
Fish have gills that allow them to “breathe” oxygen dissolved in the water. Water enters the mouth, passes over the gills, and exits the body through a special opening. This keeps an adequate amount of water in their bodies and they don't feel thirsty.
Research has proven a bass has "memory" which lasts no longer than fifteen minutes. But, repetitive behaviors condition fish. That's why they become "hook smart." It's also why they "learn" to come to fish food.
Use carbon or mild steel hooks (not stainless steel) with minimal protective coating. This way if you lose the shark before it is landed the hook will rust out within a few weeks.
Catch-and-release fishing is cruelty disguised as “sport.” Studies show that fish who are caught and then returned to the water suffer such severe physiological stress that they often die of shock.
Catch and release can be as cruel or as gentle as you make it. Catching a fish and dragging it over rocks, allowing it to be injured is cruel, even if you put it back alive. However, catching a fish, and playing it to the boat or bank, and removing the hooks while it's still in the water, that's pretty decent.
Many fish that are caught with hooks in their mouths may scrape or rub them against rocks until they break off. If it stays there longer and the metal starts to rust, the fish will come off more easily.
Fish who are caught and then returned to the water suffer such severe physiological stress that they often die of shock, or their injuries may make them easy targets for predators.
Damage to the Fish – Barbed hooks can cause a lot of damage to the fish if you are trying to set it free. Barbless hooks come out easily.