Dale,
I share your interest in Lewis and Clark. I got the audio version of the great book done on their expedition. Really enjoy reading about how they managed to make it across. It was really as nearly impossible as going to the moon was 40 some years ago.

What I find interesting, also, is that there is good evidence that the early Macedonians caught trout using a hook covered with bright wool and having feathers affixed. I think there is evidence they did so as far back as 300 AD.
So, you wonder if the native Americans also did so in what we now call Yellowstone Park. They must have seen fish rising to insects. Am sure they fashioned some sort of an imitation of an insect and flipped it out on the water - very early fly fishers????