Since several billion people rely on fish for their protein, having to farm grain and then farm fish is much less efficient and intelligent use of resources than limiting "wild" fishing to a sustainable harvest.
Several billion people can really run thru a hell of a lot of fish! Maybe it's time to wean them on to something else. Soylent green comes to mind!
Well the Europeans and Japanese are doing their part by reducing their population naturally. The US is only at stable population when you eliminate immigration. Better access to birth control might send the population into reverse.
The Chinese population will start to shrink once it peaks in a few years too.
It is just those Arabs and Africans who can't stop breeding it would seem.
Although I think I just baited a large number of people with that last comment, the reality of my statement is that the richer you get, the greater the likelihood that you population goes down. It also lowers resource use, but could theoretically make you richer per person.
At the end of the day 70 people using 100 units of resources have less per person than 40 people using 80 units even though resource use is lower.
The earth is a paradise with 2 billion people. It will be hell with 10.