HntnFsh,

The is a lot more water than acid in a fish's mouth, and hooks last a lot longer than 2 or 3 days. I don't know how long a hook can stay lodged in a fish's mouth in freshwater. If the hook is in a fleshy or bony part of the mouth, and not in the throat or a gill arch, I'd take the time to remove it - being careful in handling the fish, of course.

A regular hook doesn't last too long in salt water, but a lot of stainless steel hooks are sold for saltwater fishing, so I would expect that they could stay stuck in a fish quite a while.

I've not seen any specific data on hook longivity in fish. Could be a paper there for a student at the U.

Sincerely,

Salmo g.