If you were in Yellowstone National Park last year, pat yourself on the back. You helped push the park's annual visitation to a record 3,640,184 heads.

A new report names the 10 ecosystems in the United States whose species are most-threatened by climate change. Among the parks included in those ecosystems are Yellowstone, Everglades, and Yosemite.

In the grand scheme of wildlife management, 25 Yellowstone National Park bison are not that big of a deal, not when the park's herds are pushing 4,000 animals. But if 25 are allowed to freely roam into Montana on land just north of Mammoth Hot Springs, they could begin laying the foundation for much greater tolerance of bison in Montana.

What were the top stories across the National Park System in 2010? There were more than a few, ranging from the tragic loss of three Katmai National Park and Preserve employees to a small-plane crash to the ongoing controversy over whether birds, turtles and off-road vehicles can co-exist at Cape Hatteras National Seashore. Let's take a look back through the year at some of the stories.