I agree with canarieslover , look at Scotland's population growth :

Population. The world population growth is, IMHO, the cause of most of such problems (man's contribution to global warming, etc.) The question is, how to control it?

defra figures and chart Wild Bird Populations in UK, 1970-2010 ClickHere The decline is quite marked.

I don't think there would be as much need for intensive farming if there wasnt so much waste in the food supply chain between producer and consumer.

WTM

You simply genetically modify the cereal crops so that they cause sterility in the human male.

Sterility in the human male is already occuring.

Google sperm count and you will find that Western men are suffering an infertility crisis. Professor Niels Skakkebaek of the University of Copenhagen presented data to the WHO indicating sperm counts had fallen by about a half over the past 50 years.

The human population explosion may eventually be self limiting. I suppose it would be surprising if chemicals that affect wildlife reproduction had no impact on human reproduction.

Pine Man

Food Service is by far the most wasteful, some restaurants chuck away 50% of the food they cook in order to keep everything on the menu available all the time.

I must admit though that when I see some families' trolleys in Asda I wonder just how much of the food will be eaten...