Guidelines for releasing undersized fish
Sustainable fisheries within a healthy aquatic ecosystem
How to release undersized fish
This pamphlet will show you how to correctly release undersized fish so that they survive to reach a larger size. Everyone who goes recreational fishing should know how to release undersized fish correctly - so the fish live to be caught another day.
A fish out of water - biological facts
The body and gills of fish are designed to be supported by water. Out of water the gills collapse and stop working efficiently. The internal organs are easily damaged by squeezing too hard or by the impact of thrashing on hard surfaces.
Fish scales are covered by a mucous layer which helps prevent infections. Rough handling, especially with dry hands, damages the mucous layer and reduces the chances of the fish surviving after release.
Avoid catching undersized fish
The best way to protect small fish is not to catch them at all. Use a larger hook and a bigger bait as these are less likely to be swallowed by small fish. Do not keep fishing in an area where most of the fish are small.
Keep the fish in the water
When fishing from small boats the best option may be to keep fish in the water while removing the hook. This greatly reduces the stress caused by handling.
Lifting fish from the water
If fish have to be removed from the water, this should be done as carefully as possible. Use a landing net with soft mesh whenever possible, especially if the hook is swallowed. Small fish can be safely lifted using the line if they are hooked in the mouth. Fish hooked in the gills or the gut should never be lifted by the line.
Put the fish on a wet, soft surface
Placing the fish on a wet, soft surface such as a wet sponge or towel will help protect the mucous layer over the scales and most fish will struggle less.
Handling fish - wear gloves
Many professional fishers and marine biologists only handle live fish while wearing wet gloves. Wet cotton gloves are the best, but cheap rubber gloves are almost as good.
For small undersized fish, you will probably only need to put on one glove. You should also ensure that your hands are wet.
Include a pair of gloves with your fishing tackle and use them when releasing fish.
Never hold a fish by putting your fingers inside the gill covers or eye sockets.
If you need to handle a live snapper, hold the back of its head in the gill cover area. If you grip from below the jaw, you should avoid being spiked by the fish.
When carrying a fish, hold it around the gill covers with one hand and support the body with the other.
Cut the line for gut-hooked fish
If a fish has swallowed the hook, it is very likely to die if you try to remove it. Do not pull hard on the line. This is sure to cause internal damage. Cut the line as close as you can to the mouth. If you lose a hook in the process of releasing a fish that would otherwise die, consider this a small price to pay for the enjoyment you gain from fishing. Never use a "gob" stick on fish you intend to release.
Getting the hook out
If fish are hooked in the mouth or lip, you should extract the hook as carefully as possible. Lie the fish on a wet, soft surface and use hook removers or long-nosed pliers to get a secure grip.
Try to push the hook back the way it came and try not to tear the mouth.
Barbless hooks make releasing mouth-hooked fish easy. You can make your hook barbless by either flattening the barb with pliers or filing the barb off.
Having removed the hook, return the fish to the water head first, as gently as you can from the least possible height.
You should know the minimum legal size limits as there are large penalties for breaking the law. The limits are set at levels that allow fish to breed at least once before then can be legally caught and taken home.
Fish are measured from the tip of the nose to the "V" in the tail. Size limits can vary from area to area. For example, the minimum size limit for snapper in the North Island fisheries is 27 cm. In the South Island it is 25 cm. The minimum size for kingfish is 75 cm. The Ministry of Fisheries believes that significant increases in the numbers of fish can be achieved in our main fisheries if people observe the minimum size limits and carefully return undersized fish to the sea.
Handling larger fish
Where possible, do not remove large fish from the water at all. A kingfish that is just sub-legal (less than 75 cm) may still be quite a big fish around 3 kg.
Kingfish are reasonably tolerant of handling, but are strong and active, and difficult to control in a small boat. One way of controlling kingfish is to leave the fish in the landing net while you remove the hook, then return it to the sea. Alternatively, use a wet towel to hold the kingfish while the hook is removed.