Geoff Thomas: Give 'em a chance

How not to hold a fish, squeezing it with dry hands. The brown bands on this snapper indicate it is stressed. Photo / Geoff Thomas

When releasing unwanted or under-sized fish, a lot can be done to ensure their best possible chance of survival. Simply tearing out the hook and throwing a fish over the side will drastically reduce its chances.

Fish are designed to be supported by the water they live in, and their internal organs are easily damaged by crushing or the impact of thrashing on hard surfaces. Their eyes are also not designed to cope with bright sunlight.

All fish have a layer of mucus covering their scales or skin which protects from infection. Damage to this layer through rough handling or dry hands can decrease the chance of survival.

Pulling a fish out of the water after a struggle is a bit like putting a plastic bag over the head of a person who has just run a marathon.

Ideally, release fish without removing them from the water at all. If the fish is hooked in the mouth, use a pair of needle-nosed pliers to grasp the hook shank and twist it free. If a fish must be lifted, use the line for a small fish, or a gaff, wet towel or gloves to release a large fish.

Hold a fish with wet hands and, ideally, carry it with one hand underneath for support. Transfer it to a wet towel or piece of sponge on a flat surface.

Fish will also not struggle if held upside down, which makes hook removal easier.

If the hook is set deep in the throat or in the gut, the fish will have a better chance if the line is cut as close to the mouth as possible and the hook left. It will soon rust or be expelled, but do not use a gob stick to remove the hook from a live fish to be released. Slip the fish into the water head-first; don't throw it high in the air.

Treble hooks cause much more injury than single hooks, and if hooking a lot of small fish it is time to use larger hooks, or move to a different spot. What tires a fish during a struggle on the line is the build-up of lactic acid in the muscle tissues as they run out of oxygen just as black smoke is produced by a fire starved of air.

When muscles start to function normally the lactic acid is burned up as the oxygen supply is replenished. If a fish is totally exhausted and lies belly-up on the surface it can be resuscitated. Hold it gently upright by the tail and push it through the water head first. Game fishermen may tow a marlin held by the bill behind a boat for some times while it recovers. Oxygen in the water running over its gills will revive it, and once the fish starts to move on its own it can be released to swim away.

Gills should never be touched, and if a fish is bleeding from the gills it will have little chance of surviving. Also, keeping a fish out of the water for long periods causes the delicate gill filaments to collapse, and it will die. It is all mainly common sense. Like all fishing; if the angler thinks about the situation from the point of view of the fish it will have a better chance of living.

Game fishers often tag fish with an internationally recognised, numbered plastic tag which can be identified if the fish is later caught again. Its growth and movements can then be analysed and the data added to the research data which helps fisheries' managers make decisions on quotas, size and bag restrictions. Such catches are best tagged while in the water. But whether a small snapper or a huge marlin, each individual fish returned to the sea or stream is one more that can breed, and may even give another angler the pleasure of catching it one day.

FISHY TIPS

* One hour out of ice during summer reduces the keeping life of fish by one day.

* Fish can be kept fresh in a fish box or chilly bin by adding plastic milk containers or the bladder from a wine cask filled with water and frozen. These no-cost freezer pads are disposable and will last all day.

* Fish can be frozen whole to avoid freezer burn on the flesh.

* To scale fish after the skin has dried or been frozen dip in boiling water first to loosen scales.

* Whether whole or filleted, fish should be frozen dry, preferably unwashed. If you like to wash the fillets use salt water if possible and pat dry with paper towels.

* To fillet fish in the kitchen, do it on a newspaper. Guts can be wrapped up and frozen until put out with the rubbish.