I tried posting this somewhere else and I don't think it went through b/c I was prompted with some type of warning that I had to log in or something. I'm new to this sort of stuff and it might have been b/c it was on another reply fron Aaron. Anyway here's someof my thoughts about wild vs stocked fish
1) hatchery fish are conditioned to pellets and eggs from the time they are fry. They know what an egg is. If I was fishing over stocked fish particularly rainbows, I would use that 1st. As they get conditioned to stream life they begin to change over to stream life forms. wild/holdovers see spawning eggs so they will hit them too. Hence eggs are a good choice for prospecting.
2) Truely wild fish tend to bolt long before you get a chance to get them in certain streams whereas holdovers and stockies tend to get very selective even with a little pressure in a short time. I also think it depends a lot on what waters your fishing and how much natural pressure is going on on top of what we put on them.
3) I think in some regards intro of stocked fish into wild/holdover populations tend to create competition so the "natives" have to become less wary temporarily. You see this on the Farmington a lot when they stock the TMA
4) Within the stream there are "trigger" fish that others respond to. They sometimes get other fish to begin to feed. They insight a feeding frenzy. I've seen this at Joe Humphreys house when he feeds his pet fish on Spring Creek. I don't what to give too much more info about him, where he lives, etc out of respect b/c he's been my mentor and friend for years and don't want to jeapordize that. We've all seen where hatches take place but the fish aren't on it yet. Well, the "leaders" haven't tuned into it yet nor have the general population. Again it comes back to conditioning. An example is Spring Creek. There are trillions of cress bugs and fish feed on them all the time ( conditioning ). All of a sudden a sulphur hatch arrives. The first day or so you can still catch fish on cress bugs during the hatch. You fish it a day or two later and start fishing cress bugs but a sulphur hatch takes place...all of a sudden you stop taking fish on the cress bug b/c they have turnedto the sulphur b/c they became conditioned to that. Joe references this in his books. I'm not just reciting what he said. This comes from personal experience as well
5) almost all of it comes down to inherent genetics and conditioning--are they tuely wild with no previous human contact? Are there a lot of natural predators? Have wilds been subjected to stockies? Are holdovers now in competition with stocked fish? So many theories and possibilities. One thing is for sure they are strange and hard to figure out sometimes