caught a 22 inch walleye the other day but didn't have scale with me. whats the formula for figuring out the weight using the length and the girth. it had about a 9-10 inch girth. i'd already filleted it before i thought to measure the girth. it was 22 inches on the nose. largest pickerel i ever caught and i was surprised because the river i was fishing is known for trophy walleye, but at my usual spot i catch nothing but bullhead. caught a good sized drum yesterday too.