Stats show that even when fish are getting released, the fish often dont even return to the spawn areas after that. Not sure why but they tagged some fish and were surprised to find this out. I watched a show on that where it was in Michigan and it was smallmouth bass. All must be released during spawning season, and these were big, fat smallmouths they were catching, and now they are thinking about cancelling catch and release and just banning fishing in certain areas for a few weeks at least until they get done spawning. It wouldn't surprise me if that is happening with other fish types besides just smallmouth, the catch and release is working they way they expected it to.