Catch and release fishing is an important conservation tool that helps to sustain native fish populations by allowing more fish to remain and reproduce in the ecosystem. This practice provides an opportunity for more people to enjoy fishing and to successfully catch fish. But catch-and-release fishing is not perfect. Some fish still die, including many that swim away after being released. Reasons for mortality after release are many including hook injury, handling practices, air exposure, and swim bladder trauma in fish brought up from depth … also known as barotrauma.
Even though catch and release fishing is not perfect, there are several best practices you can employ to increase the survival rates of released fish, thereby increasing the sustainability of the fishery.
Being prepared with the proper landing and release gear as well as with the most fish-friendly hooks are both important catch and release best practices. It is also important to make sure that the appropriate bait for your target species is selected. Also note that when collecting live bait from the wild, you run the risk of collecting juveniles of regulated species. As such, it’s important that anglers are able to recognize juveniles of sportfish that must be released instead of going into the live well.
Several studies have shown that the use of circle hooks reduces mortality when compared to J-hooks. This is because circle hooks are far more likely to hook a fish in the mouth leading to less throat and gut injuries and easier hook removal. Other conservation practices related to hooks include bending barbs down to make hook removal easier and removing one set of hooks when using treble hooks.
Another best practice is limiting handling and air exposure time. Landing a fish using equipment such as knotless, rubber-coated nets, handling fish with wet hands (never gloves or a towel) and using proper dehooking tools are all best practices that aid in the survival rates of released fish. If a hook does not come out easily, use pliers to clip the leader as close to the hook as can be done safely. Non-stainless-steel hooks are preferred as they will rust out if the hook cannot be removed. Even when these best practices are applied, handling is still stressful for the fish.
Handling & Taking a Photo
But, did you know that one of the most stressful events for the fish can be the process of taking a photograph? Capturing a catch on camera is a great way to share your experience with others, create lasting memories, or maybe even a few bragging rights. But a fish should not be held out of the water for long periods of time just for the purpose of taking a picture. Each moment out of water is a lost breath for the fish.
Remember, when taking a picture, hold the fish horizontally and support its weight with both hands. This decreases the possibility of damaging the fish internally. If unsupported, large fish such as snook will rupture their isthmus – the connection between its head and body necessary for the gulping action during feeding. When this happens, the fish is unable to swallow and will die a slow death from starvation. It is also important not to put fingers in the gill cavities, as this can damage sensitive gill filaments by compressing or collapsing them and reducing the fish’s chance of survival. Whenever possible, take pictures of the fish while in the water. This makes a great photo and conveys the message that the fish was destined for release.
Releasing Your Fish
When you do release the fish, gently release it headfirst into the water. If the fish is exhausted, revive it by moving it forward in the water or by holding it facing into the current, allowing water to flow through its open mouth.
If you are targeting sharks, use lots of drag and heavy enough tackle to limit extended fight times. Longer fight times could mean the shark will be at a higher risk of mortality. (Prohibited or protected species that die while on the line after being caught must be returned to the water.) Think about what size shark you will be catching. The bigger the shark, the heavier the tackle should be. Use a dehooking device to remove hooks safely. Longer handled tools work better for sharks. Do not remove sharks from water – extended air exposure could be deadly. Take photos with the shark in the water.
Often overlooked is best practices for baitfish. Many baitfish species, particularly whitebait, are very sensitive to handling. Never take more than you need and when you’re done fishing, release leftover bait in suitable habitat for its survival. While in the livewell or bucket make sure the water is aeriated. Most baitfish have short lifecycles. Wasted baitfish means less fish to spawn, resulting in less food (offspring) available in the future for your target species.
Deep Water Reef Fish
Another best fishing practice applies when fishing for reef fish in deeper waters. Many marine reef fish have a gas-filled organ called a swimbladder, which controls buoyancy and allows the fish to maintain a certain depth in the water column. The gas in the swimbladder can over-expand or even burst when fish are brought quickly to the surface from deep water via hook and line, resulting in injury known as barotrauma. If the fish is released in this overly buoyant condition, it may have difficulty returning to depth and may float away and die from exposure to the elements or become an easy target for predators. This defeats the purpose of fishery management laws such as minimum size restrictions and daily bag limits.
You have two basic choices for mitigating barotrauma: venting or descending. Both of these barotrauma mitigation strategies provide a means to help reef fish return to depth, thereby reducing release mortality. Choose an option that is best suited to your local fishing conditions and practices that will cause the least injury to the fish and you. It is important to have a plan for releasing a fish brought up from depth before landing it. Time is crucial in keeping a released fish alive, so work quickly for quick releases with minimal handling. Watch our barotrauma videos here.
Some final thoughts: even when a fish does not die, there’s a whole host of non-lethal effects that occur in stressed fish. These stressors include altered blood chemistry, behavioral impairments, depressed growth and reproductive rates, and increased vulnerability to disease. These non-lethal effects can be magnified due to other environmental stressors such as increased water temperature, low dissolved oxygen levels, and also long fight and handling times, and general mishandling of the fish.
We All Can Play a Role
Everyone can play a role in conserving fish populations. By practicing good catch and release anglers can help to ensure native fish populations survive to reproduce in the ecosystem. This in turn will help to sustain fishing opportunities for in future.