I see your point but I cannot see a parallel in hunting. I do not think it's an ethics issue either. It's a risk abatement issue for wild fish. Risk abatement is attitive the more steps you take to reduce risk the less risk you have. So if the goal is to protect wild fish then it seems we have an arbitrary set of standards that says one risk is less than the other. That hypocrisy opens the door to the otherside saying catching the fish in the fist place puts the fish at more risk than trying to release it in the second place. So stop catching them to reduce risk to wild fish. I can think of no other example where you are even allowed to touch a protected spiecies,can you?