I hope I will be able to make it out there for this one.

Until recently, I was in the Candlemaking Industry. I always seem to have some candle wick with me. One of the ways I measure fish is to go from nose to tail, tie a knot and then get the girth on the other side of the knot. This way you have a physical record of length and girth. Perhaps a tag (tourney ticket?) at the knot with a photo would be a good way to keep track.