I had a guide point at my Corkies today and tell me, "You know you aren't going to catch anything with those, right? You know these fish don't bite Corkies?" I had another guy a couple days ago tell me that anyone farting around with a Corky bigger than a pea was wasting their time in the Rogue. Then there's a guy on YouTube who says anyone fishing Corkies is flossing, whether they know it or not (a suggestion that I find as insulting as I do ignorant):
http://www.youtube.com/watch?v=Y8iz3u5_djU
Anyone fishing with a 6-foot leader might be flossing, but that's a separate discussion.
I've spent years plunking Corkies in Alaska. My favorite spot to fish up there is in this big back eddy. It's a popular spot. Guys throw out a half-ounce to an ounce — just enough to keep the setup from moving around in the current — and park their weights right on the bottom. To Drew's point, leader length will vary, anywhere between 18" and 36", but no one is trying to floss anything with a 3' leader. I'm not even sure flossing can be done with such a short leader. Indeed I'll go as far as to say it is impossible to floss a fish while plunking… period. How can you floss if the weight isn't even drifting? If you've ever plunked for salmon, you know what I'm talking about.
Now, can I explain why Alaskan kings are hitting the Corkies? No, I cannot. My understanding is that spawning salmon stop eating the second they hit fresh water, but will strike all sorts of presentations throughout their journey up river. Are salmon striking spoons and spinners out of habit, because they remind them of yummy things that they used to eat like herring and other bait fish? Or do they strike something like a Vibrax and Wiggle Wart because the flashing + audible vibration is agitating? Who knows? No one really studies this stuff with any kind of serious, academic research. It's all theories, conjecture and insights from old fishermen.
I don't think there's any correlation between a fish hitting a Corky and "hunger." What I always believed is that salmon become increasingly aggressive as they get deeper into their spawn. When I'm plunking Corkies, the fish are trying to rest in a pool or back eddy, but there's this thing in their face that's irritating the crap out of them, so they hit it. I don't think the fish has any intention of swallowing it, which should address Drew's question about why you don't find a rainbow of metallic colors in their gullets. When a fish is pissed off, the only thing it really has to express its frustration is its mouth.
I know a lot of guys think salmon are eating roe because they are "hungry," but this isn't the case with salmon that are spawning in rivers. Salmon stop eating in fresh water, and roe is no exception. The explanation that always made sense to me was that salmon (and other spawning fish) will instinctually eat any eggs they run across during their migration because they know those eggs aren't theirs. They were left by other fish at another time. So the spawning Chinooks will give their own fry the best shot at survival by eating the eggs of others, thereby reducing the number of fish competing for resources.
So to summarize, can I explain why salmon bite on Corkies? Or spoons? Or plugs, naked or wrapped with bait? Or roe? Or why scents work? Nope, I can't. But what I find very perplexing is that so many people think salmon in the Rogue don't bite, especially Corkies. It just makes no sense to me that a 20# Chinook will nail a proper Corky setup in Alaska but won't here in Oregon. What's the difference? Is it the fish, or just what the fishermen believe?
I find the pervasive line of thinking along the bank of the Rogue very discouraging: Chinooks don't bite, you can't attract them, and flossing is the only really effective way to catch them. Yeah right… if that's true, then why do guys in boats get them to bite?