We attached one of those plastic bulletin boards that comes with a washable marker and keep track with hash marks, so we can tell which of us is "winning" .
We usually only fish with one pole, never more than two (It's the law), so keeping tabs isn't a big deal. We rarely keep more than six fish - enough for a meal or two for the two of us - and release the rest. BTW, A fish has to be boated to be counted. - Roberta