First of all, you've got it backwards. Wild fish may have been spawned in the river, not the hatchery, but are not necessarily the native strain. They could be hatchery escapees, or the result of hatchery fish spawning in the river.

Hatchery/wild stocks spawn at a different time than the natives, so they don't (theoretically....this still gets debated) interbreed.

"All this C*** about protecting this fish and that fish.....Phoooooey!"

Have you never heard the stories of wild fish being wiped out because we though we were doing the right thing by introducing other species for our own recreation? We've done it in lakes and rivers both (seems to me there was a major screw up in one of the Montana lake/stream systems having to do with a sockeye run, but can't put my finger on it without some research).

I'm pretty clueless on the subject compared to some, and I'm sure you'll get some much more detailed responses than I can provide. You're definately going to hear from somebody.