@dalehileman,
The people who believe we are currently overpopulated were the same ones several decades ago who were predicting world wide famine if we ever approached our current 7 billion.
Considering that we have only explored approx 0.5% of out oceans, it's very difficult to credit any assertion that we've exhausted 90% of its food resources.
As for the depletion of the world's oxygen, your expectation is misfounded. Ocean plankton accounts for more of earth's oxygen than of all it's forests combined.
This fact alone would argue for greater slaughter of whales (at least those of the baleen variety) since they are great harvesters of plankton.
Obviously there is a finite number of people who can live on this planet, but it's more than the current 7 billion and so a statement that there are already "too many of us," if it has any credibility, must be based on some criteria other the ability of the earth to sustain human life.
You, spendius and Cieli, seem to think there are currently too many of us, and I'm interested in the basis for your assessments.
I'm also interested in your thoughts on how the problem is to be resolved.
The population of the developed nations are in decline and so if the overall population is increasing it must be due to those randy and fertile buggers in the undeveloped nations. How to slow them down? Force contraception on them?
We, in the developed world, can't get them to stop clear cutting forests so how the hell will we get them to stop having babies?
I suspect that the current crop of Malthusians see a way to save Gaia and serve the godess of Social Justice at the same time: Redistribution of wealth from the developed nations to the undeveloped.