It is very important that the fish is kept in the water after being captured and the fish should be supported from beneath, with the hook gently removed either by hand or by means of long-nosed forceps or hook releasing tool. If a hook is deeply embedded and cannot be removed, the leader should be cut close to the hook, as fish released with the hook attached will generally survive, and try not to squeeze the fish too hard, and never hold it by the gills at all times.
Releasing and reviving the fish
After removing the hook, or cutting the leader and leaving the hook or fly in the fish, then we should ensure that the salmon will be supported in the water, facing into the current to allow oxygen uptake by the fish's gills, and given sufficient time to the fish for it to recover. Hold the fish gently until it is capable of swimming away strongly, you will know it is time when you feel it starting to pulse and kick softly. If you release the fish and it turns 'belly up' then quickly capture the fish and support it again for a while facing into the current to allow more oxygen to be absorbed. When the fish is being fought there is lactic acid produced in the muscle tissue which creates oxygen debt and the muscles cannot function adequately Indefinitely.
Avoid weighing the fish if at all possible and if you have to then weigh the net with the fish enclosed in it, a Maclean net is suitable for this. Available here
. A tape measure or a marked off wading stick can also be used to take the approximate length while keeping the fish in the water.
Alternatively, to accurately measure a big fish capture, an angler can run a length of monofilament or fluorocarbon from a spool, measuring from the fork of the tail to the nose of the fish and tie a knot. Continue to run the mono round the girth of the fish and tie another knot. By cutting the mono just above the second knot the angler has a length that he/she can measure against a tape measure later. Ally Gowans has a calculator for predicting the size of fish which is available on the internet here
I am sure anglers will find this advice most helpful. Perhaps one day beats may supply this information to visiting anglers on small laminated leaflets with beat conditions. Survival rate is greater at water temperatures below 20°C so be aware of the necessity to quickly subdue and return the fish during the summer months.
Survival chances of released salmon
There has been research carried out by a number of fishery trusts that has shown that the survival rate of salmon caught and released may be close to 100% when we apply the above guidelines and practice.
Spawning success and viability of eggs may be unaffected in salmon caught and released in late autumn using the above guidelines, and they can recover within twenty four to forty eight hours of being captured and are able to spawn successfully.