This is interesting.
I know the North Atlantic Shark, - it is poisoned if you cook it right away. So, it has to rot for a while to be edible (those poisoned materials dissolve easily)
Anyway, afterthe process, it is a healthy (however horrible) meal.
And this:
"It's also a very good idea to gut it and clean it out quickly after landing it. I find that by doing that you eliminate some of the slight fishy aftertaste some species have.
"
I know this from trout fishing in muddy lakes, - better gut them right away, or they won't taste.
Just 4 hours of waiting will make a big difference.