Images

During the past decade populations of this honeycreeper have begun to rebound at lower elevations on most of the main Hawaiian Islands, in spite of high prevalence of infection with avian malaria.

USGS Researcher Calin Tatu sampling a spring in a Balkan endemic nephropathy (BEN) village in Romania. Samples of water are tested for the presence of toxic organic compounds that are linked to BEN.

USGS researcher examining bass for abnormalities in the field.

Researchers implant a radio transmitter in a 16-foot, 155-pound female Burmese python (Python molurus) at the South Florida Research Center, Everglades National Park. Radio-tracking builds understanding of where pythons spend their time and therefore where they can be controlled in practice. Photo courtesy of Lori Oberhofer, National Park Service.

A closeup of the Fosheim Peninsula on central Ellesmere Island where the wolf, Brutus, was radio-tagged.

A couple of hours after being immobilized for collaring, Brutus, a wolf being studied by USGS scientists, appears to have fully recovered. He returns to his pack mates and demonstrates dominance behavior over a younger male wolf. Note that Brutus has a stiff, aggressive stance and upright tail, while the younger male cowers.

Reflection of autumn cedars (green and orange needles) in a calm pond with downed woody debris. Taken in the Cascade Mountains of the Pacific Northwest.

Sunlight through an autumn fern (with spores structures) in front of a downed old-growth cedar tree.

A scientist from the North Carolina Aquarium removes an invasive red lionfish (Pterois volitans) found in coastal North Carolina's hard bottom habitat, to prevent ecological impacts due to its predation and competition with native fishes.

Accessing a release site for salmonids implanted with radio transmitters. Behavior and movement of salmon are monitored as they migrate through the Toutle River.

Returning via jet boat from a juvenile salmon fish release after a warm rain.

Water levels are critical to the life cycle of alligators. Part of the Everglades restoration plan is to determine what historical water levels and flow rates supported healthy alligator populations.

Beach Sampling for Forage Fish Spawn on Whidbey Island in Puget Sound.

A northern pintail duck wearing a transmitter.

A male northern pintail duck.

California condors are one of the most endangered birds in North America. In the early 1990s, captive-bred condors were reintroduced into the wild in California. As of January 2010, about 190 condors now live in the wild and more reintroductions are being considered.

Sage-grouse have declined throughout their entire range, largely due to the loss and fragmentation of sagebrush habitat.

A colorful clay-colored sparrow nest. These sparrows live in brushy grasslands and prairie habitats.

Elk congregate on the Camp Creek Feed Ground in northwestern Wyoming.

Bighead carp are a large and troublesome invasive species from Asia found in the great rivers of the central United States.

Silver carp are a large a troublesome invasive species from Asia found in the great rivers of the central United States. Silver carp have been observed to jump in response to rocks thrown in the water, passing trains, geese taking off from the water, or just when they unexpectedly find themselves in a tight place.