You're going to get an influx of speargunners looking a cheap alternative to divorce...
In all seriousness, our California Fish and Game are pretty much like that when it comes to abalone. They'll watch violators in progress of poaching, but wait until they get back to their vehicle to make an arrest, as they get to confiscate any gear used to take or transport illegally harvested abs.
We can't shoot any fish that touches fresh water at any time during its life cycle, but there's a pretty good spearfishery for halibut, lingcod, cabezon, kelp bass, and rockfish.
For those who are into blue water freedive spearfishing, halibut, white sea bass, yellowtail, dorado, and yellowfin tuna seem to be the primary game.