One of New Zealand’s best known guides, Tony Entwhistle, writing in the New Zealand Fish & Game Magazine, has one of the best descriptions I have read on the proper handling of a trout.
“Securely handling a trout without causing stress or damage is a matter of a gentle touch, not a tight grip.
To pacify a landed trout, simply place a hand vertically in front of its nose to prevent it from swimming forward and fold the palm to cover both eyes. This acts as a mask and immediately calms it down. Trout relax quickly when their eyes are covered.
Next grasp the fish’s tail with the other hand, without excessive force. Some anglers use a piece of stocking for grip, but with good technique this isn’t necessary. Securing a trout needs only gentle pressure between the thumb and forefinger, applied directly over the base of the tail, applied where it joins the body (hypural joint).
Apply pressure top and bottom through the first joints of the forefinger and thumb, rather than along the sides. The mistake is grasping the tail too far forward and using too much hand in doing so. Squeezing hard does not help as the fish slips more easily.
Now test the grip by lifting the fish slightly by the tail, keeping the other hand over the eyes for the moment. If the grip is secure the trout will not slip, but if it does resist grabbing at it with both hands. By quickly slipping a hand in front of the nose, and covering the eyes again, a lot more fish will be saved from premature release.
With a positive grip on the tail it is now possible to begin lifting the trout safely for a photograph or release.
Avoid squeezing the fish around the soft belly area behind the pectoral fins because this causes discomfort and can potentially cause serious damage to internal organs. Instead slide the free hand under the pectoral fins, orientating the hand so that the trout’s head rests along the index finger, with the pectoral fins spread out between thumb and little finger.
The trout will be nicely balanced and the soft tissue in the belly area will no be supporting any weight. Lifting the trout this way, and returning it to the water between photographs minimizes any distress which could reignite its struggles. Turn the fish belly up when removing the hook.
Handle trout gently and with respect and they won’t panic or stress, ensuring their revival for release without damage and a minimum of fuss.”
© Reproduced by permission – ‘New Zealand Fish and Game Magazine’