"The disappearance of wildlife in many regions has at least been slowed down through the creation of different kinds of protected area, and about 13% of the Earth's land surface is now in some form of conservation management (up from about 1% in 1960)."
Juniper, Tony. "Which Way Now?" Resurgence. Nov./Dec. 2011. 37. http://www.tonyjuniper.com/content/which-way-now [verified 4/17/14]