I am asking this question because I am trying to make my diet less cruelty-oriented, for this reason this question can be related to trolley problem since I am coping with an ethical problem trying to minimize the the core aspect i.e. suffering.
On the contrary I would like to know what kinds of fish suffer the least after being caught. I know that shrimps/prawns die very quickly since they cannot breathe out of the water, for instance here I have read that prawns die after just a couple of minutes out of water. But for medium/small size fish is different, especially for those which are mass-caught. Not to mention the explosion of bowels caused by rapid pressure variation.