Looking for a way to "give back a little" at Yosemite National Park this summer? The park's volunteer Habitat Protectors program offers a chance to do just that every Wednesday; no experience or advance registration is required for individuals or small groups.

More oil was coming ashore Friday in parts of Gulf Islands National Seashore, with tar balls several inches in diameter seen near Fort Pickens on Santa Rosa Island. In Washington, D.C., meanwhile, a top Republican was calling for the Obama administration to lift the moratorium on off-shore drilling.

The common raven is one of the brainiest birds you'll encounter in the national parks, but the same keen intellect that makes this species interesting and amusing also makes it troublesome.

There might be no finer time to hike in Arches National Park than early mornings, when the soft light of the rising sun glints off the red-rock and the spindly Utah junipers and waves of fins cast long shadows.