Technically, you can't fish for kings in a river that's not open for them.
How the Hell do you enforce that? I've "steelhead" fished the lower Skagit in the summer with floats and eggs, surely catching more kings than steelhead, but actually fishing for steelhead. Pulling a diver and a Kwikfish with a sardine wrap is not a generally recognized steelheading technique.
I saw B'ham's local warden (if you're up there at all, you know exactly who I mean) ticket a gentleman on the Nooksack in December fishing with drift gear because he caught four straight chums and continued to cast into the same hole. This was before the North Fork Nooksack was opened to the chum fishing, about seven or eight years ago. Even using steelhead gear, this guy was fishing for salmon where it wasn't open, at least according to Mr. Woods. This seems much less egregious than pulling divers and wrapped plugs after "steelhead".
This seems like a pretty tough rule to enforce. What if you summer run fish with a spinner, or eggs, or a jig? It is only a matter of time before you run across a springer or a coho that is not to be kept at that time or in that stream.
How about if you are fishing in a river that is open to both salmon and steelhead, but catch an otherwise legal springer on a spinner with a treble hook, while at the same time the regs call for a non-buoyant lure restriction ( no treble hooks on lures that don't float when fishing for salmon). By the rules, that fish goes back, even though you were legally fishing and caught a fish that the river is open for. Try to enforce that one in the "real world"!
As with almost all of our fishing regulations, self-regulation is the only way to really enforce them. With one warden every six or seven rivers, I'm sure that 99% of game violations are never discovered. How you want to self-regulate is entirely an issue you need to discuss with yourself.
In my opinion, fishing for steelhead and catching a salmon, which is immediately, and hopefully competently, released, will happen and will be a nice bonus for a day of steelheading. Pulling divers and wrapped plugs that are six or seven inches long is fishing for salmon, and if it's not open for salmon, you're breaking the law.
On a lighter note, my Zipperlip produced a big fat zero on steelhead yesterday, but drifting naked eggs on a size four Gammie with a six foot leader of eight pound test hooked me up with a hot 13 pound springer. Besides being a strong fighter, this fish was damn near chrome, and the river was actually open for springers, too. Guess what I'm BBQ'ng tonight?
Fish on...
Todd.
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Team Flying Super Ditch Pickle