Catch and release maybe ought to be what you describe, but since so many fisheries are moving in that direction due to overuse, the cops are not going to look at you that way. And depending on how you look at it mortality rates are a part of catch and release fishing so you are consuming the resource by so doing. With cold water species like trout, the mortality rate, as reported by fish friendly publications, is pretty high. I have had my doubts about these reports since I have fished places where the fish were like trained seals and rolled on their sides and waited for you to remove the hook (Yellow Breeches). However, these are also places where the standard fly is about the size of the j on your keyboard, size 22 ant, so they are virtually fish velcro.

There are two other approaches, hooks with the loop at both ends, you get a tug, and maybe you might see the fish, but in the end he lets go. The other option is hooks without the bend and you get the rise, for instance. But you should be aware that even these could get you into trouble. First of all many places will prosecute you is you have a rod within x of the water, and what if you are carrying flies that are real, just not on your line. Most places you are toast. Further, some places have laws that say, yes you can kill our fish or stick them as part of fishing, but if you aren't fishing you can't bother them. So if you hook a fish but prove you weren't fishing, then you were harassing a fish, and you get prosecuted anyway, though possibly you don't loose the bike.