How to Remove a Hook Without Injuring the Fish

By: Charles W. Bryant
Exploring nature's adventure outdoors.
Fishing Image Gallery Fly-fishing lends itself to easier hook removal and a successful catch and release. See more pictures of fishing.
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It's called a sport, but some enthusiasts­ might dub it meditativ­e. Silence is golden. At the crack of dawn in quiet solitude they sit in boats, stroll lakeshores and riverbanks or wade waist-deep into rushing streams. Then the waiting begins. Despite what you see on fishing shows, it can take hours to get a bite. If your luck is down, you may spend an entire day without as much as a single tug. Fishermen are lulled into an almost Zen-like state, listening to the click of the reel and the plop of the lure hitting the water, birds singing and breeze blowing. Then, out of nowhere, the fish hits the line, sending the angler's adrenaline level through the roof. The once-lazy, loose fishing line is now alive, taught and jerking back and forth. The rod that was stick-straight and pointing skyward moments ago is bent at an improbable angle toward the water.

From this point, many fishermen practice something called catch and release. Instead of hanging the fish on a chain stringer or tossing it in a cooler of water, the catch-and-release fisherman removes the hook from the fish and places it back into the water with great care as quickly as possible.


Forty-four million Americans hit lakes, rivers and oceans each year to fish recreationally, ringing up a tab of $41 billion along the way [source: Reiss, et al.]. It's a booming industry. To help conserve the fish population, regulations are put in place that only allow fishing during certain times of the year. The same goes for how many and what size fish you can keep. The National Park Service encourages catch and release of all native species. It also recommends keeping non-native fish, as long as they meet the size restrictions, to allow the natives to thrive.

The trick to performing a successful release is making sure that the fish doesn't suffer any injury. Most serious sports anglers are well acquainted with the techniques that work and keep the fish in good health. Many part-time fishermen may not be as informed. We'll walk you through the steps to take for a humane release and fill you in on exactly how fish can be harmed in the process.


Why Fishing Hook Removal Kills Fish

You can switch out the treble hooks on this lure for easier hook removal.
Ronald C. Modra/Sports Imagery/Getty Images

Fish live underwater and they're mea­nt to stay there as much as possible. They suck water through their gills, taking oxygen directly into the bloodstream through tiny capillaries. They have an outer mucous membrane coating that helps them fight topical disease. This coating must be kept wet at all times. The very act of taking a fish from the water can cause it a great deal of harm. That's why experienced catch-and-release sportsmen are very careful when they de-hook and reintroduce a fish into the water. And they do it as quickly as possible.

Fish can put up a heck of a fight when they're on the end of your line. But while a fish possesses excellent defense techniques, the act of attempting to free itself from the hook takes a lot out of the creature. When you see a fish struggling against the fishing line, jumping from the water and thrashing, it's depleting its tissue of oxygen through the stress of exertion. An oxygen deficit soon occurs, and the muscles begin to function without it. This causes lactic acid to build up on the muscle tissue, and that lactic acid eventually finds its way into the bloodstream. The pH, or measurement of the blood's alkalinity, drops because of the addition of the acid. Once the blood's pH is disrupted, it can mean curtains for the fish.


So how do catch-and-release fishermen hit the lakes and rivers without a guilty conscience? If they're skilled at landing and handling the fish and can remove the hook quickly, then the fish's blood will most likely go back to normal and everyone is happy. But if the fisherman takes too long to land the catch, then the fish could die, as much as three days later, from the imbalance in the blood. It's all about time. An experienced catch-and-release angler tries to get the fish back in the water as quickly as possible to prevent this from happening.

Another reason a fish can get injured is from the hook. Ideally, you hook the fish in the mouth -- it's called shallow hooking. Shallow hooking also includes the cheek and jaw. Deep hooking refers to a fish being hung on its belly, through the gills or deep into the throat near internal organs. Hooking the gills and stomach area is likely to kill the fish. Deep sea fish can also have trouble in surface pressure, just like a scuba diver does.

Then there's the matter of the mucous membrane layer on the skin. If you handle a fish with dry hands or gloves, or use a course, dry net, then you stand a good chance at removing much of this slimy layer. This opens the door for bacteria and pathogens to come into contact with the fish, potentially killing it.


Barbless Fishing Hooks and Other Fish Lifesavers

Flies everywhere!
Fishing flies are tied by hand and a good bet to land a shallow mouth hooking.
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The quest to become a responsible catch-and-release fisherman starts with the kind of tackle you use. There are two ways to attract a fish. One is with bait­, and the other is with a lure.

Bait can be anything from a worm to a can of sweet corn. Lures come in all shapes and sizes, but they usually look like a small fish and have multiple hooks. Some bass lures don't look like fish, but simulate attractive movement with shiny spinning metal spoons. Bait is more likely to cause a gill or stomach hook, which is bad.


Treble hooks, which have three prongs, are more likely to puncture and wound the fish as well. Many lures come with treble hooks, but you can replace them with single hooks. They even get through the water easier that way. Fly fishermen use tiny artificial flies made by hand that have similarly low mortality rates.

There two basic types of single-pronged hook -- J-hooks and circle hooks. J-hooks look like a letter 'J.' Circle hooks have a similar shape, but the bottom of the 'J' is typically wider, and the point comes around more toward the stem instead of straight up. Using circle hooks is less likely to result in deep hooking. For each, you also have the option for tiny metal barbs along the metal. Barbed hooks are tougher to get from a fish's mouth.

­You can speed up the time it takes to remove a hook by only using barbless hooks or crimping the barbs with some pliers. It's also important to buy hooks that are appropriately sized for the fish you're trying to catch. If the hook is too large it can do more damage. A strong line also helps to get the fish in quickly.

So you've got your barbless circle hook, and you're using a lure instead of bait. The fish hits your line, and it's time to land it. Bring the fish in quickly and efficiently using a steady and deliberate technique. You should never pull the fish from the water using the line. You need to man up and do it with your hands or a net. If you use a net, use one made of knotless cotton mesh or rubber that's less likely to harm the slime layer. Some fishermen don't advocate the use of a net at all.


Remove the Hook Right

Catch of the day
Bass have strong, wide mouths that can be used to safely hold the fish.
Michael Edwards/Getty Images

Fish caught in shallow water can inju­re themselves thrashing around on rocks. So if you're in a river angling for a nice brown trout, try not to land it in shallow water. Look for a deep pool nearby. Once it's time to get the hook, see if you can do it with the fish still in the water. If you need to get the fish out of the water, wet your hands and lift it, holding it firmly by the tail and supporting it gently under the belly. Avoid touching the gills or squeezing the fish.

Use needle-nose pliers to remove the hook. Grasp the hook by the stem and, while holding the fish in the water, twist and pull gently, backing the hook out the way it came in. Don't ever wiggle the hook or pull with too much force if it's snagged. If the fish is gut-hooked or the hook is too deep into the throat, it's best to cut the hook as close to the body as possible and leave it in there. Many times the hook will simply dissolve and get spit out. The fish has a better chance at living than if you struggle to free the hook.


Once the hook is out, you need to revive the fish. "Tossing a fish" back into the water should remain an expression. Never throw a fish into the water. If you're bass fishing, you can hold the fish by the lower jaw and ease it back into the water. If it's a trout or another non-bass, lower the fish headfirst with both hands the same way you handled it out of the water, supporting the belly. If it's a river catch, point the fish with its head upstream in a slow current. You may need to help it out some by moving it gently back and forth to allow water to flow into the gills. The same holds true for lake fish. Once it begins to come around and tries to swim away, simply release your grasp. Larger fish may take a little longer to revive.

If you plan on catch-and-release fishing, be prepared ahead of time. Get the proper tackle, have your pliers within easy reach and the camera ready. Fish can only live for a few minutes out of the water, but you should never even come close to using this amount of time. Try and keep the time out of the water to less than 30 seconds. Experienced catch-and-release fishermen never allow the fish to leave the water at all.


Lots More Information

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More Great Links

  • Alaska Department of Fish and Game. "Catch and Release." 2008.
  • Anderson, William D. "Catch and Release - How to do it Properly.", 2008.
  • Fish and Wildlife Research Institute. "Catch-and-Release Fishing." Florida Fish and Wildlife Conservation Commission. 2008.
  • HookOff. "Catch-and-Release Fishing." Sept. 8, 2006.
  • Reiss, P., Reiss, M. and Reiss J. "Catch and Release Fishing Effectiveness and Mortality." Acute Angling. 2008.
  • Schwartz, Malia and Williams, Erik. "Catch-and-Release Fishing.", 2008.
  • ScienceDaily. "Going Fishing? Catch-and-release In Less Than Four Minutes, Please." Oct. 1, 2007.
  • ScienceDaily. "Going Fishing? Only Some Catch And Release Methods Let The Fish Live." June 4, 2007.
  • Texas Parks and Wildlife Department. "Catch and Release Fishing." 2008.
  • U.S. National Park Service. "Catch and Release Fishing." 2008.