Images

Yukon Delta National Wildlife Refuge, Alaska.

Yukon Delta National Wildlife Refuge, Alaska.

Yukon Delta National Wildlife Refuge, Alaska.

Yukon Delta National Wildlife Refuge, Alaska.

Unhatched eggs in Brewer's sparrow (Spizella breweri) nest.

Landsat image of Maui, Hawaiʻi, with the small island of Kahoʻolawe to its south.

View of the Green River along a trail in Mammoth Cave National Park.  USGS operates gages on the river above and below the Park Boundaries. 

View of the Green River along a trail in Mammoth Cave National Park.  USGS operates gages on the river above and below the Park Boundaries. 

Coconut palm, sea grapes, and a white sand beach overlooking Drake's Passage from the island of Tortola in the British Virgin Islands.

Birds found in and around the Salton Sea, California.

USGS hydrologist conducts a ground-penetrating radar survey to investigate and characterize the shallow subsurface. The survey was conducted as part of an applied research effort by the USGS Office of Groundwater Branch of Geophysics in 2006.

USGS hydrologist conducts a two-dimensional (2D) resistivity survey to investigate and characterize the shallow subsurface. The survey was conducted as part of an applied research effort by the USGS Office of Groundwater Branch of Geophysics in 2006.

Tropical rainforest vegetation including tree ferns, epitphytes, vines, bromeliads, and a waterfall in a mountainous rainforest garden.

Side view of giant panda. Mei Xiang is a female panda at the National Zoo in Washington D.C. She is being studied by scientists in efforts to save the endangered species.

Side view of giant panda. Mei Xiang is a female panda at the National Zoo in Washington D.C. She is being studied by scientists in efforts to save the endangered species.

A forested glade along the Fern Lake Trailhead in Rocky Mountain National Park.

Tree ferns and profuse tropical vegetation framing a mountainside waterfall, visible in the background, in a rainforest garden.

Tree ferns, ephiphytes, bromeliads, banana plants, and other rainforest vegetation framing a waterfall, visible in the background, in the tropical rainforest mountains.

Giant panda on grass. Mei Xiang is a female panda at the National Zoo in Washington D.C. She is being studied by scientists in efforts to save the endangered species.

Tree ferns and a waterfall visible in the background in a mountainous rainforest garden.

Bird Banding Station - Master bird bander, David Mitchell, collects a cloacal swab sample from a gray catbird during a capture-recapture study at a Monitoring Avian Productivity and Survivorship (MAPS) program bird banding station. The sample will be tested for avian influenza and other diseases.