Here's a simplified thought about what is going on. The fish evolved a behavior pattern that allowed them to be successful. It may have been to get out of the ocean, hold for freshet, the bolt. Whatever.
Over the decades we remove them. What spawns is what survives. There are wild coho in PS that are now spawning in December/January and later. Why? because their parents did.
For a long time I scoffed at the the idea that hatcheries, especially, bred non-biters. Again, if you harvest 90% of the run, and much/most is with hook and line just what does live?
Basically, what spawns is what doesn't get caught.
(Un-) Natural selection at its finest.
Give that man a GOLD star.
This is why it's important that the big ones get away and we let a few go to keep the biter trait alive and well.
Maybe that's why we catch so many stinkin' tules in the lower Columbia?
"Let every angler who loves to fish think what it would mean to him to find the fish were gone." (Zane Grey)
"If you don't kill them, they will spawn." (Carcassman)