Cooked Fish is obtained from cooking Fish with a Campfire, Fire Pit, or the summoned star from a Star Caller's Staff. Like other cooked foods, it cannot be dried on the Drying Rack; however, slowing the spoil time by cooking is inconsequential when Fish are plentiful.
When examined by certain characters, such as Wilson, the character will say, "Now I shall eat for a day." This is a reference to the proverbial saying, "If you give a man a fish, he'll eat for a day. Teach him to fish, and he'll eat for a lifetime."
When a Fish is on the ground, it flops around, then perishes, its eyes becoming crossed out.
Wickerbottom's favorite food is Fish, judging by her examination quotes. This is referring to fish being considered a "brain food".