Images

Bats hibernating in a cave. 

Muddy Creek in the San Rafael Swell with white surface salts. 

Coral reefs are prone to phase shifts where they quickly transition from coral-dominated to a uniformity of other organisms, typically algae. The Palmyra Atoll National Wildlife Refuge in the Central Pacific is a unique case where a transition from corals to corallimorphs occurred.

While these gates might look similar to the entry way of a medieval castle, they are actually part of a scientific experiment that will help scientists design more effective fish passage structures for American Shad. Photo by Kevin Mulligan, USGS.

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It looks like a holiday ornament, but this lovely object is a single-celled freshwater alga from the desmid family, found in the marshes of Florida’s Arthur R. Marshall Loxahatchee National Wildlife Refuge. USGS biologist Barry Rosen photographed it at 200x magnification using ultraviolent light and a fluorescence microscope.

Yellow Creek near Oak Grove, IN - downstream of bridge

Non-native Cuban treefrogs have established a breeding population in New Orleans, Louisiana, the first such population on the U.S. mainland outside Florida. The treefrogs were discovered at the Audubon Zoo shortly after a shipment of palm trees from Florida were planted in the zoo's elephant enclosure in 2016.

This HiRISE image cutout shows Recurring Slope Lineae in Tivat crater on Mars in enhanced color. The narrow, dark flows descend downhill (towards the upper left). Analysis shows that the flows all end at approximately the same slope, which is similar to the angle of repose for sand.

Animated GIF of lava bubbling up from Kīlauea Volcano in Hawaiʻi Volcanoes National Park. The source of the GIF comes from footage found within the USGS video: Kīlauea Summit Eruption | Lava Returns to Halemaʻumaʻu.

Animated GIF of a scientist at Kīlauea Volcano in Hawaiʻi Volcanoes National Park looking back and forth using a range finder. Footage found in the USGS video: Kīlauea Summit Eruption | Lava Returns to Halemaʻumaʻu.

Photo of Lake Powell. 

USGS scientist Jessica Rodysill studies a sediment core to help understand past environmental conditions. This core was collected from Maryland. Credit: Elizabeth Goldbaum, USGS. 

Tropical Storm Nate's predicted effect on Northern Gulf sandy shorelines, based on landfall as a Category 1 hurricane,  is shown at three intensities. Outer band:  Dune erosion. Middle band: Dune overwash. Inner band: Dune inundation, with potential flooding behind the dune. Credit: USGS Coastal Change Hazard Portal.

Yellow Creek near Oak Grove, IN

Kanakee River at Davis, IN - downstrean of bridge

Scientists use mealworms to train two lesser scaup ducklings to peck at a target after tones are played at certain frequencies. This species was studied as part of research by the USGS and partners to identify the frequencies at which sea ducks can hear underwater.

A common eider duck. This species was studied as part of research by the USGS and partners to identify the frequencies at which sea ducks can hear underwater. The research can help inform decisions on the use of sound devices to deter ducks from fishing gillnets and other threats.

Two common eider ducklings. This species was studied as part of research by the USGS and partners to identify the frequencies at which sea ducks can hear underwater.