Being caught is stressful, scary, and injures fishes. Most are hooked through their mouth or eye, crushed, suffocated, severely exhausted, or suffer from decompression injuries, such as parts of their gut forced out through their mouths and anuses, their swim bladders to burst, and their eyes to bulge out. Some suffer on hooks or lines for hours or even days. Many die in the process of being captured. To take them out of the water or net, they are usually stabbed with a stick with a hook or barbed spear at the end, called a gaff.
In trawling, a large net is dragged through the water or along the ocean floor and catches any animals in its path. Fishes caught by trawling are chased to exhaustion, panic as they are captured, and are scraped and injured by the net. Some suffocate or are crushed to death under the weight of others. One study showed that 29% to 61% of fishes in the net died. Fishes who are lucky enough to escape the net may also die. A study showed between 30% to 72% of escapees die, usually from skin injuries or exhaustion. When trawling in deep water, fishes suffer decompression injuries. Trawling, and in particular shrimp trawling, catches a lot of non-target animals, including dolphins, whales, turtles, seals, and more.
In purse seining, a large net slowly surrounds fishes, and is closed at the top like a drawstring bag. Fishes are scared and stressed, sometimes on purpose to prevent them from leaving the net before it’s closed. They may be attacked by predators during capture, experience severe exhaustion, and are injured from close confinement with other fishes and scraping the net. When the net is lifted out of the water to bring them on board, many are crushed to death. If the net catches too many fishes, some will be deliberately let out of the net, but most of these die (up to 90%). They may experience decompression injuries. Purse seining also catches many non-target animals.
gill, tangle, and trammel nets
A gillnet hangs in the ocean and ensnares unlucky animals who swim into it. Fishes are snared by their gills, which effects their breathing so they feel like they are going to suffocate. They panic and become severely exhausted from trying to free themselves. Fishes can be caught in the net for hours or even days. They are seriously injured by the net when trying to free themselves. One study showed that 28% of fishes died in the net, and this increases with longer capture. Some fishes are attacked by predators when ensnared in the net. When the gillnet is brought on board and fishes are taken out of it, they usually suffer further injuries. Fishes who escape the net on board are impaled on a gaff.
Tangle and trammel nets catch fishes by entangling them instead of snaring their gills. Fishes caught by these methods likely suffer similarly to those caught by gillnets, except fishes can usually continue breathing normally so they suffer less severe physical injury. Nets catch anyone in their path, so using them results in catching many non-target animals.
rod & line fishing & trolling
In rod and line fishing, fishes are caught individually on a hook and line. In trolling, baited lines are towed through the water. Fishes caught on hooks are scared, panicked, stressed, and in pain. Most fishes are hooked in or around their mouths or through their eyes. They become severely exhausted and experience even more injury when the line they are hooked to is pulled in. They can be stabbed with a gaff to bring them on board.
pole & line fishing
In pole and line fishing, live fishes are used as bait. They are impaled on hooks or thrown into the water to stir up a feeding frenzy. Fishes are then caught on hooks, swung aboard and slammed onto the deck, which disengages them from the hook.
Fishes who as used as live bait suffer severely for a long period of time. They are scared and distressed from being captured, confined (it may be for days or weeks), and being dropped into unfamiliar environments, impaled on hooks, and unable to escape predators.
In longline fishing, hundreds to thousands of baited hooks on one line are placed in the water for hours or days. Sometimes live fishes are impaled on the hooks as bait. Fishes who become caught suffer on the hook until the next time the line is checked, which can be hours or days later. They are often attacked by predators. This method of fishing also catches many non-target animals.
Baited cages are used to capture fishes. Fish who are confined feel stressed.
Fishes are slaughtered in brutal ways, and are forced to suffer for minutes or even hours, slowly dying.
Two brutal methods are often used to kill wild caught fishes: suffocation and live gutting. These are intensely prolonged ways to die. How quickly fishes lose consciousness is dependent on their species, how well they are adapted to tolerate low levels of oxygen, their escape response (activity burns up their oxygen reserves), and the temperature.
Fishes who are gutted alive are either disemboweled or have their gills cut. They can lose consciousness in five minutes, or up to thirty minutes to an hour after being gutted. Fishes who are suffocated can lose consciousness anywhere from three to ten minutes to one to four hours.
Fishes are also sometimes put on ice as they suffocate, which prolongs the time to lose consciousness in some species, but decreases it in other species.
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