I was researching farm raised fish and came across a fish that was storing fat. A picture showed a fish cut open and it showed the fat. I can't remember the name.

I believe all fish store fat during certain times of the year. It's a natural instinct to survive through winter.

Tropical fish may not store fat seeing as how they never have to adj. to colder weather.

Pikes, Trout and other types of fish that live in the forever changing seasons will have the ability to store fat. I don't think just any one fish does it.