ABCNEWS.com : Motley Group Builds Safe Passages Calculations show Conservation International plus two other environmental groups have placed almost 1.4 percent of the terrestrial Earth under protection. That's a lot of Earth. Why go to the trouble?
Consider the red fox — they're hardly a rare animal, but at Yosemite National Park the red fox has vanished.
In other national parks, grizzly bears, lynx and river otters have disappeared. Harvard professor and eminent biologist Edward O. Wilson says there's a pattern here — national parks are "leaking" species.
"Species are going extinct in the parks with no particular pressure being put on them by hunting or disturbances of the habitat by humans," he says. "[National parks are] the greatest idea America ever had with reference to the environment, but they're not enough to hold on to all our species."