With a multi-year cleanup completed, efforts are now under way to return native species that once called Mountain Lake to the lake that's on the grounds of the Presidio in San Francisco.

We splash downstream in The Narrows of the North Fork of the Virgin River, deep in the backcountry of Utah’s Zion National Park, mostly craning our necks up like turkeys hypnotized by falling rain. But our fascination is not with rain, but red walls on both sides that rise hundreds of feet overhead. The sun does not find us in this deep canyon, where the air temperature approximates the inside of a refrigerator, and the ankle- to calf-deep water feels about the same.

How can someone spend anywhere from $500 to $3,000 for a drone, drive to the Marin Headlands portion of Golden Gate National Recreation Area, walk several hundred yards from the parking lot along with dozens of other visitors, commence to flying his drone on the trail to the Point Bonita Lighthouse, and claim not to know he was in a national park?

This past winter saw an earlier-than-usual decline in snowpack on Yellowstone National Park roads, one that forced the park to shut down access to some snowmobilers and snowcoaches. While some might write that off to simply an unseasonal winter, record-keeping in the park shows less snow is falling there and that in some parts of Yellowstone the once-typical Rocky Mountain winter is much shorter than it used to be.