Should you feel the need to weigh a fish, the only safe way of doing so is in a net or fish sling. Never hang a fish on a weighing device such as a lip/Boga grip. This will cause all sorts of internal damage and result in holes and tears in the fish’s mouth that may impair its ability to feed (can’t create proper suction) and exposes the fish to secondary infections. With the fish in a net or sling, simply attach the weighing device and gently lift it out of the water. Allow the excess water to drain and then record the weight. Then determine the fishes weight by subtracting the wet weight of the net/sling.
Revival and Release:
Before we release a fish, we want to make sure that it is in good enough condition to survive after being released. To accomplish this, we need to revive the fish properly after landing and handling it and make sure that the fish can breathe and move freely before being released. The goal is to promote the flow of oxygenated water over the gills and there are numerous methods that can be used to achieve this.
In moving water, the best practice is to hold the fish with its head facing into the current while supporting its underside or gently holding its lip. For fish with teeth, this is the only time I would recommend the use of a Boga/lip grip. Allow the fish to move and breathe in the current and observe for signs that the fish is getting stronger (tail kicking). In a still water environment revival becomes trickier and some have suggested moving the fish in a figure 8 pattern to induce water flow over the gills. One thing that should be avoided is pushing the fish forward and then pulling it backwards. Fish were not designed to swim backwards and this may damage the gills.
This begs the question; how will we know when a fish has been successfully revived and can be safely released back into its environment? To answer this question, researchers at Carleton University have developed a set of reflex tests that anglers can use to assesses the condition of fish before they are released. These tests have been devised to test the built in reflex responses of fish and based on the reaction of the fish to these tests, the fishes condition can be better assessed. The test is a series of 4 successive steps and is described here with photos for examples of each test method and the fish’s response.
The only time a Boga grip should be used, to revive toothy fish.