[buzzbaiter]

You wanna know how many trout are in a stream(or bass in a lake)? Fish it! Sounds pretty easy to me and your not handling them unnecessarily. I never got the whole survey thing myself. Spend enough time fishing somewhere and you'll know what a place holds by what you catch(or don't catch). You can also look in the water and see spawning beds or young fish. Over in Pa, they actually clip the tips of the fins so that when they re-shock(second pass) the stream, they don't count those fin-clipped. Seems pretty harsh to me just for a routine survey. They do grow back but that's beside the point.