I know every single essay in this contest is going to say that exact thing, but it is a bi g issue. First of all, don't throw away an entire fish. If you had a fishing contest and you caught so many fish you don't know what to do with them, don't throw them away. Give them away, hold a fish party, do whatever. Just don't chuck them.
People have to remember that fish are alive.
They have feelings. One thing to think about is that when you're fishing for fun, with no intention of keeping the fish, don't use a barbed hook. It wouldn't be very fun to be straggling around in a place you can't breathe with someone vainly trying to pull something out of your neck with not too much success. I know that it would be pointless to tell everyone to stop fishing salmon. I don't even want people to stop fishing salmon.