It is absolutely, without a doubt, imperative that you address the SOURCE of unwanted litters in your community, regardless of how many animals you rescue. Ignoring the source is the fatal error that is a direct cause of animals dying in your community. You will NEVER be able to rescue as many animals as are being bred if you ignore the "Free to a good home" advertisements. NEVER. It is no lie that they can breed far quicker than you can adopt. Period.
http://www.ahimsatx.org/nnl/docs/HowTo.htm
http://www.ahimsatx.org/nnl/docs/HowTo.htm