Catch-and-release fishing can be an effective way to conserve fish if certain precautions are taken. Studies with striped bass have shown that mortality of released fish goes up substantially when the water temperature is higher and when salinity is low. If possible, you should try to avoid these situations.
Whether fishermen choose to release fish or are required to do so by law, all released fish must be handled carefully to have a good chance for survival.
The angler controls four factors that affect a fish's chance of survival:
- Exhaustion: The fight is tough on the fish. It can upset the fish's chemical balance if it lasts too long.
- Loss of Slime: Fish have a slime coating that seals out infection. Rough handling can destroy this protective layer.
- Time Out of the Water: As longs as it is out of the water a fish can't breathe or restore its chemical balance.
- Wounds: Anglers can do a lot to minimize the damage of hook wounds both before and after the fish is hooked.
Here are some tips for careful catch-and-release fishing:
- Use strong enough tackle. Many fisherman like to use light tackle to be more sporting, but any fish you plan to release should be brought to the boat quickly to minimize exhaustion.
- Use artificial baits whenever possible. Fish tend to swallow natural baits, but are usually hooked in the lip or mouth with artificial baits. A lip wound is much less severe than a gut wound.
- Use barbless hooks. They are much easier to remove from a fish than barbed hooks, meaning less wounding and time out of water. Barbs can easily be bent or filed down on bait hooks or artificial lures.
- Set the hook quickly when using natural bait so the fish does not have time to swallow or
- Use circle hooks when fishing with natural bait to minimize gut woulds. Studies have shown that circle hooks rarely gut-hook fish. It is important to let a fish take the bait and hook itself with circle hooks.
- Reduce the use of treble hooks to minimize wounding and time out of water. Often, single hooks can replace trebles or tines can be clipped without ruining the lure. Experiment!
- Have catch-and-release gear ready (including camera and ruler) to shorten time out of water.
- Keep the fish in or over the water. There will be little or no slime loss or time out of water.
If you must remove the fish from the water:
- Remove the fish carefully by supporting its weight in an upright position with your hands and lifting straight up; or
- Use a shallow landing net, preferably of rubber or knotless nylon. These nets will remove less slime and will reduce wounding and time out of water.
- Keep control of the fish so that it cannot flop around and cause further wounds or loss of slime.
- Handle fish carefully using wet cotton gloves or a wet towel to minimize slime loss. If you must use your hands be sure to wet them first.
- Cradle the fish on its back and cover its eyes. This will calm the fish, reducing wounding and slime loss.
- Always avoid touching the gills. This is where the fish takes in oxygen and salts from the water when recovering from the exhaustion of the fight. Gills are very delicate.
Removing the Hook
- Use a dehooker to remove a hook quickly, keeping the fish in or over the water. You can make or buy a dehooker.
Dealing with difficult hooks:
- Carefully remove hooks inside the fish's mouth, gill or gullet with tools like forceps or needlenose pliers that can firmly grasp a hook.
- When the hook is in the stomach, use a disgorger or deep throat-type tool to remove the hook quickly with minimal stress or cut the line and leave the hook.
- If a fish is obviously injured, make this fish part of your creel and adjust your technique to avoid the problem.
- Carefully return the fish to the water after removing the hook. Hold it in or close to the water and release it upright and head first.
- Revive an unresponsive fish by moving it gently forward in the water to relieve its exhaustion.