Easy pick for me:
The Spyderco Pacific Salt with plain edge blade. The Atlantic Salt is smaller and has more of a sheepsfoot blade shape that I don't think would be as handy for cleaning fish.
My Spyderedge version is in my pocket right now as I did some kayaking this afternoon.
Great knives, great steel, and the clean linerless handle design would be as easy as any folder to remove gunk from. (But a fixed blade would sure be easier!)
Stay sharp,
desmobob