I fished for them quite a lot our west but can't comment on the GL kings... I am sure someone will.
The problem I observed in Pulaski was that many are fishing for them using less than honorable means and it degrades the experience for those who aren't. I don't think I saw any fish hooked in the mouth when I was there during the fall king run but I just stopped at the big easy access pools.
A pod of kings will become very wary once they feel there are threats from the shore and it turns the bite off, which makes anglers get more devious, which turns the bite off even more, and the anglers get more itchy, a vicious cycle that leaves the honest angler out of the circle.
I used to fish in tidewater out west before the crowds had a shot at them and did much better; I would imagine the same applies here. I would pay the fee and fish Douglaston Salmon Run down low.
The fish I caught out west were ocean run kings up to 38 # and a real test for the tackle. They would turn on and off like a light switch in terms of grabbiness for flies on the swing. Best times were twilight, morning and eve. I did best where the fish were close to the mouth but stopped or slowed by some structure. It seemed they would get awful anxious and sometimes rip the rod out of the hands, other times a subtle dull weight turns out to be a fish.
One thing's for certain - they are BRUISERS.
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