Catch and release is a practice within recreational fishing intended as a technique of conservation. After capture, the fish are unhooked and returned to the water before experiencing serious exhaustion or injury. Using barbless hooks, it is often possible to release the fish without removing it from the water (a slack line is frequently sufficient).
• 1 History of practice
• 2 Catch and release techniques
• 3 Debate
• 4 See also
• 5 References
• 6 External links
 History of practice
In the United Kingdom, catch and release has been performed for more than a century by coarse fishermen in order to prevent target species from disappearing in heavily fished waters. Since the latter part of the 20th century, many salmon and sea trout rivers have been converted to complete or partial catch and release.
In the United States, catch and release was first introduced as a management tool in the state of Michigan in 1952 as an effort to reduce the cost of stocking hatchery-raised trout. Anglers fishing for fun rather than for food accepted the idea of releasing the fish while fishing in so-called "no-kill" zones. Conservationists have advocated catch and release as a way to ensure sustainability and to avoid overfishing of fish stocks. Lee Wulfe also promoted catch and release as he observed the Atlantic Salmon population dwindle.
In Australia, catch and release caught on slowly, with some pioneers practicing it the 1960s, and the practice slowly becoming more widespread in the 1970s and 1980s. Catch and release is now widely used to conserve — and indeed is critical in conserving — vulnerable fish species like the large, long lived native freshwater Murray Cod and the prized, slowly growing, heavily fished Australian bass, heavily fished coastal species like Dusky Flathead and prized gamefish like striped marlin.
In the Republic of Ireland, catch and release has been used as a conservation tool for atlantic salmon and sea trout fisheries since 2003. A number of fisheries now have mandatory catch and release regulations. Catch and release for coarse fish has been used by sport anglers for as long as these species have been fished for on this island. However catch and release for Atlantic salmon has required a huge turn about in how many anglers viewed the salmon angling resource. To encourage anglers to practice catch and release in all fisheries a number of Governement led incentives have been implemented. 
Catch and release is mandatory for some species in Canada, which also requires, in some cases, the use of barbless hooks to facilitate release and minimize injury.
 Catch and release techniques
Professor with pinched barb
Effective catch and release fishing techniques avoid excessive fish fighting and handling times, avoid damage to fish skin, scale and slime layers (that leave fish vulnerable to fungal skin infections) by nets, dry hands and dry surfaces, and avoid damage to throat ligaments and gills by poor handling techniques.
The use of barbless hooks is an important aspect of catch and release; barbless hooks reduce injury and handling time, increasing survival. Frequently, fish caught on barbless hooks can be released without being removed from the water, and the hook(s) effortly slipped out with a single flick of the pliers or leader. Barbless hooks can be purchased from several major manufacturers or can be created from a standard hook by crushing the barb(s) flat with needle-nosed pliers. Some anglers avoid barbless hooks because of the erroneous belief that too many fish will escape. Concentrating on keeping the line tight at all times while fighting fish, equipping lures that do not have them with split rings, and using recurved point or "Triple Grip" style hooks on lures, will keep catch rates with barbless hooks as high as those achieved with barbed hooks. Triple Grip treble hooks work particularly well with the barbs crushed.
To make a hook barbless, just use something like a pliers and sandpaper to get rid of the barb. Then penetrate the hook through some clothing and pull out. If the hook catches on the way out, the hook isn't completely off.
Key aspects of catch and release include:
• Using strong tackle, to minimise fighting times
• Using needle-nosed pliers to aid unhooking
• Using barbless hooks, for quick, easy hook removal and reduced handling times
• Leaving fish in the water during the unhooking and release process, to avoid any handling
If fish are removed from the water for unhooking and/or a photo, key aspects of handling include:
• Avoiding the use of landing nets; if landing nets must be used, specially designed catch-and-release landing nets (e.g. Environets) are used
• Avoiding touching the fish with dry hands or dry surfaces (e.g. shirt fronts) or putting them down on dry surfaces (e.g. rocks, boat gunwhales, boat bottoms)
• Only touching the fish with wet hands and wet surfaces (e.g. wet towel)
• Avoiding hanging fish from their jaw/mouth/gills
• Holding fish horizontally, and supporting large fish with a second hand under the belly
• Minimising time out of the water (e.g. 20–30 seconds)
The effects of catch and release vary from species to species. A number of scientific studies have shown extremely high survival rates (97%+) (e.g. ) for released fish if handled correctly and particularly if caught on artificial baits such as lures. Fish caught on lures are usually hooked cleanly in the mouth, minimising injury and aiding release. Other studies have shown somewhat lower but encouragingly high survival rates for fish gut-hooked on bait if the line is cut and the fish is released without trying to remove the hook. This procedure should be followed for any gut-hooked fish intended or required to be released.
Catch and release is criticised by some who claim it is unethical or immoral to stress fish for sport or amusement. Some oppose catch and release only but do not oppose fishing for food, per se.
Proponents of catch and release dispute the suggestion that fish hooked in the mouth feel pain. Many point to the fact that fish consume spiny, hard prey items such as crayfish, molluscs and other fish, and require a tough, insensitive mouth to do so; such a mouth is unlikely to feel a hook point. Some point to studies that claim fish lack the higher brain functions that physiologists often associate with the ability to feel pain. And some quote the many observations fishermen have made of fish succeeding in throwing a lure and then turning around and striking the same lure again, an unlikely behaviour if being hooked in mouth causes pain. Similarly, all observations from fishermen support the contention that hooked fish fight because they feel the pull of fishing line, not because the hook in their mouth hurts. Suitably strong tackle reduces fighting times and reduces stress on captured fish.
Opponents of catch and release point out that fish are highly evolved vertebrates that share many of the same neurological structures that, in humans, are associated with pain perception. They point to studies that show that, neurologically, fish are quite similar to "higher" vertebrates and that blood chemistry reveals that hormones and blood metabolites associated with stress are quite high in fish struggling against hook and line, resulting in increased mortality. The idea that fish do not feel pain in their mouths has been studied at the University of Edinburgh and the Roslin Institute by injecting bee venom and acetic acid into the lips of rainbow trout; the fish responded by rubbing their lips along the sides and floors of their tanks in an effort to relieve themselves of the sensation. Lead researcher Dr. Lynne Sneddon wrote "Our research demonstrates nociception and suggests that noxious stimulation in the rainbow trout has adverse behavioral and physiological effects. This fulfils the criteria for animal pain." However, others argue this may demonstrate a chemical sensitivity rather than pain; notably, no similar result has been obtained with trauma, such as using fishhooks. Thus, the evidence for pain sensation in fish is ambiguous. Some anglers accept the arguments that fish are highly evolved vertebrates that can feel pain, but again point out that that fish have tough, bony mouths that often consume spiny, hard prey items, and that hooks therefore do not cause fish pain, despite fish being capable of feeling pain.
Ultimately, and regardless of claimed ethical issues, catch and release is a conservation practice, developed out of necessity to prevent overharvest of fish stocks in the face of growing human populations, mounting fishing pressure, increasingly effective fishing tackle and techniques, inadequate fishing regulations and enforcement, and worsening habitat degradation. Scientific studies are showing generally high rates of survival for released fish — which is the aim of catch and release — and the alternative of banning or severely restricting angling is generally unreasonable or not feasible. Fishermen have been practising catch and release for decades now, including with some highly pressured fish species, and no significant, measurable effects from catch and release have been observed, indicating that mortality rates from catch and release are not excessive. Conversely, had recreational fishing for these highly pressured species continued to the present on a totally catch and kill basis, some of these species fisheries would certainly have collapsed by now.