One of the best things you can do to ensure that the fishing will remain great in your favorite lake is release the fish you catch. Unfortunately, it's not enough to just 'toss the fish back' after you unhook it. Many fish that are released die later due to a number of reasons. In this article I'll explain some of those reasons and tell you what you can do to avoid unintentionally killing a fish.
Let's start with hooks. Obviously a fish hooked in the lip is going to be better off than a fish that is hooked in the gullet or gills. It's easy to remove the hook from a fish's lip without doing major damage, but it's not so easy when the fish is gut hooked. For gill or gut hooked fish, it's better to simply cut the line off as close to the hook as possible and release the fish. Never try to pull on the line to free the hook. This can cause severe damage to the fish and will always do more harm than good. I've caught catfish that have had rusty hooks embedded in their throats, and bass with big rusty buzz baits in their mouths so I know first hand that many of these fish will live. Eventually the hooks will dissolve and the fish will spit them out. In some cases you can cut the eye of the hook off and gently slide the hook out, but this isn't advisable if you have to pull the hook up to get at it.
When a fish is hooked where you can easily remove the hook without tearing him up, use a pair of pliers. Try to avoid wiggling the hook to work it back out. This puts more stress on the fish. For most of the lip hooked fish that I catch, I can grasp the hook with a pair of pliers, and while holding the fish in the water, twisting my wrist to simultaneously unhook and release the fish. Try to avoid holding the fish with your hands because you will wear away his protective coating. I'll explain more about this in a minute.
Some anglers use barbless hooks, or crimp the barbs down with pliers. This makes unhooking a fish quick and easy. If you know how to retrieve a fish, you won't loose any fish because your hook lacks a barb.
When unhooking a fish, the longer it takes, the more stress you put on the fish. You've heard the saying "Stress kills". It also applies to fish just as it does to humans, only more so. The longer a fish is out of water, the less his chances of survival. Fish that are quickly returned to the water can sometimes be caught again later. Some tagged fish are an example of this. There have been countless fish caught, tagged, released, and then caught again later. Sometimes they are caught years later. Even if they are not caught, they might enhance the fishery by producing offspring.
While a fish is out of the water, the way it is handled can make a big difference. Try to avoid touching the fish’s body with your bare hands. If you have ever touched a fish then had your hands smell or had that slimy feeling, that's the protective mucous coating. This coating helps protect the fish from disease and should be left in tact as much as possible. If you must handle a fish by its body, wet your hands first. I've seen gloves that supposedly prevent damage to the mucous coating but have never tried them. Soft wet gloves are better than nothing, and they will help keep the smell off your hands. Avoid nylon or winter gloves because they are no better for the fish than dry hands.
For bass and other fish that don't have teeth capable of removing your fingers, you can hold the fish by their lower jaws. Some catfish may not be able to puncture your skin with their teeth, but the bigger ones can certainly crush your fingers to the point of breaking them. There are devices available that allow you to grab muskies, pike, and other large fish that have teeth. One that I've seen is similar to a towel that wraps around the fish with a handle at each end. This allows you to hold the fish and keep your hands while at the same time allowing the fish to keep most of his protective mucous coating.
The type of net you use makes a difference too. Try to avoid netting a fish when possible. But if you must, use a cotton mesh net or something other than hard nylon. Some have said that certain rubber nets are ok too, but I've never used one. Also, avoid the use of "knotted" nets. These knots act like sandpaper on a fish and can easily remove scales or damage eyes. Another type of damage occurs when the tissue between the spines on the fins gets ripped. This impairs the fish's ability to swim properly. Never try to net a large fish with a small net either. No matter what the material, you'll do a lot of damage if the net is too small to properly accommodate the fish.
Prior to netting the fish, the way he is played makes a difference too. When a fish is hooked, he will fight to free himself. This requires a great deal of energy. When a fish fights, he builds up lactic acid in his muscles very quickly. This is similar to what happens to us when we exercise. If you've ever had sore muscles after a workout then you understand what I'm talking about. In fish, this build up is highly toxic and can cause death days later. To prevent this, avoid 'playing him out' and retrieve the fish as quickly as possible.
Getting the fish in quick is even more important in warmer water. Fish are cold blooded and will always expend more energy in warmer water. So it makes sense that they will fight harder too. The harder they fight, the more energy they expend and the more lactic acid they will produce.
Once you have caught the fish, be very careful not to let him flop around. Fish can bruise themselves or even cause serious internal injuries that can kill them later. Be careful not to drop a fish. If you hold the fish incorrectly, chances are you're going to get the slippery protective coating on your hands and it will slide right out of your grasp. Fish can also shake and break your grip. Don't squeeze a fish to keep him from flopping. If you need a second to get your camera ready, place a wet towel under and over the fish. The bottom of your boat, or the ground will damage the fish so it's important that something wet and soft be on both sides of the fish.
Besides building up lactic acid, a fighting fish uses up oxygen. They can become out of breath just like us. The quicker he's brought in, the less out of breath he'll be and the more likely he'll be able to swim away without the need to be revived. Some people scoff at this notion because fish don't breathe through their mouths (note that some species such as catfish are capable of breathing through their mouths). They don't think about the fact that fish have lungs and a heart just as we do. When we're out of breath, it's because we've used up a lot of oxygen. We breathe faster to take in more air and out hearts beat faster to get the needed oxygen replenished throughout our bodies. Fish are no different, but they are not as well equipped to catch their breath.
Fish need to move to breath, if they are out of breath, they lack the energy to move which prevents them from taking in more oxygen. Sometimes they are so out of breath that they can't move their gills to force water over them. When this occurs they are unable to breathe and they die. If you wind up with a big one on the end of your line, sometimes you have no choice but to fight the fish. When this happens and the fish runs out of energy, he can be revived. Place the fish in the water belly down and gently grasp him by the tail. If you're in a river, point him up stream. Slowly move him back and forth until he lets you know he's ready to take off. Be careful not to remove any of his protective coating. Most of the time they'll kick loose and be gone, but other times you'll need to repeat this more than once. Try not to let the fish go until he's ready. This is very important in current because he can be carried into rocks or other objects and be injured. I've also heard people argue that fish don't need to move to breath. They mention fish that sit in weed pockets as examples. Those fish aren't expending energy or burning oxygen like they would be if they were on the end of your line. They also have enough energy to move their gills as needed.
There is one exception to the rule of bringing the fish in quickly and that is when you hook a fish at a depth of around 30 feet or greater. Any one who's ever had scuba training knows that if a diver comes up to fast from great depths too quickly, he will get what's called "the bends". Something similar can happen to fish and it's almost always fatal. If you're going to be catching fish from great depths, it often best to keep them. If you're out for sport, it's best to target shallower fish. It's very difficult to ensure that a fish brought up quickly from 30 feet or more will live.
When bringing in fish from the depths, it's often good to pause every few feet or so. This allows the fish to decompress and is similar to the same concepts taught in scuba classes. The trade off here is that the fish will still expend energy and build up lactic acid while he is hooked. Also, it may require 30 minutes or more for a fish to adjust his pressure so unless you're going to fight the fish for that long, you might as well keep him.
I've heard that fish brought up from deep water will need their swim bladders popped. This is nonsense. Never stick a needle into a fish to puncture anything. You can be sure the fish will die if you do this. Sometimes the bladder will expand so much that the stomach will be popped out of the fish’s mouth. There's nothing you can do in this case but keep the fish. As I said earlier, if you plan to release what you catch, target fish shallower than 30 feet.
Some fishermen have devised methods to return fish back to deep water by using materials threaded through a fishes jaw that will break off when tugged. I have my doubts about this practice. Any fish that has had its swim bladder exert extreme pressure on its internal organs, or has his stomach protruding from its throat has been damaged.
Another important thing you can do to help release your fish in good shape is to be prepared. Are your pliers within reach? Is the camera ready? Anything you can do to get the fish back in the water as quickly as possible will help ensure its survival. If you have everything you need within your reach, you won’t have to keep the fish out of water any longer than you have to.
Some people like to weigh trophy fish before they release them. When you weigh a fish, try to use a scale that allows you to place the fish on it, or place the fish in something that will be lifted. Most scales have a hook on the end and do damage to fish. Never place this in the eye of a fish, or in his gills. Place the fish in a wet towel and lift it with the hook. Remove the fish and weigh the wet towel and subtract the weight of the towel to get the weight of the fish. Or, zero the scale out with the towel attached, and then weigh the fish.
An alternative to using a scale to obtain the weight of a fish is to carefully measure the length and girth of the fish and then use the calculator I have provided at the bottom of this page. Unless a scale has been certified as accurate, you’re only getting an estimate anyway. I once weighed a fish on 3 of the most popular scales sold in tackle stores and got three different results.
When you release a fish, gently set him back in the water. Never throw a fish back or toss him through the air into the water. This will always harm the fish. If you are able to hold the fish by the lower jaw, gently lower him into the water and let go. Other fish should be released belly down and pointed slightly towards the bottom. Never hold a fish by his gills or eyes. Remember to allow enough time to revive any fish that might need a little extra help.
Never place a fish that you're going to release on a stringer or in a fish basket. A stringer run though the gills is always a death sentence. Any time you scrape anything across fish’s gills, you impair his ability to breathe. Try to avoid live wells when possible too. Some live wells have valves or handles in them that the fish will come in contact with. Many of these surfaces are not smooth and will remove scales or scrape off the protective coating on a fish. A live well can be a good place for extra storage.
Once you've caught your trophy you can preserve the memory by taking a quick photo or two. Since you are releasing the fish, a good photo is a very important part of preserving the memory that you've just experienced. Practice your photography techniques when you are not fishing. Study the pictures that you have taken. Try to figure out what you could have done better. A digital camera is a good investment because you can delete any bad photos, and you don't have to print the ones you don't want. Some come with viewfinders that let you review the photo you just took. You know right away if you need to take another picture.
Some of the things I've learned about taking pictures are very simple like making sure the sun is behind the camera. Also, try to have something else in the picture that will allow someone else to get a good grasp of the true size of the fish. This can be a ruler, the seat in your boat, your fishing reel, or your hand. A nice full body shot of you and the fish also makes for a good memory.
Catch and release fishing is all about preserving the sport of fishing. When you take the time to learn to handle a fish properly, and are able to release him unharmed, you are ensuring that others will be able to enjoy the sport in the future.
bass weight = (length x length x girth) / 1,200
pike weight = (length x length x length) / 3,500
sunfish weight = (length x length x length) / 1,200
trout weight = (length x girth x girth) / 800
walleye weight = (length x length x length) / 2,7000