Thanks for the research and response, CFM! beer
Perhaps I read it wrong, but I see no mention of restrictions outside of being aboard a vessel.
I have no interest in filleting on the river, but the adipose fin could be left intact on at least half of the fillets without a problem. I'm surprised that the only apparent roadblock to filleting on site is that you be finished fishing for the day. (Dolley Varden excepted...who keeps these, anyway?)

Am I missing something? confused
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