The growth and movement of human populations can have incredible impacts on animal populations. If this is news to you, well... I just don't know what schools are teaching kids these days. :) The New England Cottontail has made the news rounds recently due to its difficulty. While similar, but different, to the common cottontail, these wild rabbits (which are relatives, but not the same as domesticated rabbits) are disappearing thanks to habitat disruption.
There's a good news article on them, and a little web site that promotes information as well.