It's quite simple. nobody is suggesting heavy harvest for commercial fertilizers. We are talking about eating what you catch and only catching what you eat. Also, I am pretty sure on green Peter where I will be fishing that the problem isn't a shortage but a surplus. Humans are the wild card of nature capable of selective harvest in order to maintain balance. If you are here on this forum about fishing, it's mighty hypocritical to whine about people eating fish. What do you do? Release them after an excruciating battle just to die of their injuries or recover maimed? Last fall I caught a bluegill that had been caught in the lip so many times his face was crippled. The poor fish was severely under weight. Catch and keep allows the fish that remain to have more food and grow faster and healthier. Native or introduced, underfishing results in starvation. Catch and release results in injury and death. As some have complained about the need for a preditor species on GP, I might point out that a human with a buzz bomb is a preditor.