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Long-term accumulation of salts in wetlands at Bowdoin National Wildlife Refuge (NWR), Mont., has raised concern among wetland managers that increasing salinity may threaten plant and invertebrate communities that provide important habitat and food resources for migratory waterfowl. Currently, the U.S. Fish and Wildlife Service (USFWS) is evaluating various water...

To compensate for authorized disturbance of naturally occurring wetlands and streams during roadway improvements to U.S. Highway 202 in Chester and Montgomery Counties, Pa., the Pennsylvania Department of Transportation (PennDOT) constructed 0.42 acre of emergent wetland and 0.94 acre of scrub-shrub/forested wetland and modified sections of a 1,600-foot reach of...

Numerical ground-water-flow models were developed for a 160-square-mile area of coastal New Hampshire to provide insight into the recharge, discharge, and availability of ground water. Population growth and increasing water use prompted concern for the sustainability of the region's ground-water resources. Previously, the regional hydraulic characteristics of the fractured bedrock...

Arrival time on breeding or non-breeding areas is of interest in many ecological studies exploring fitness consequences of migratory schedules. However, in most field studies, it is difficult to precisely assess arrival time of individuals. Here, we use carbon isotope turnover in avian blood as a technique to estimate arrival...

Acoustic measurements made using compressional-wave (P-wave) and shear-wave (S-wave) transducers in aluminum cylinders reveal waveform features with high amplitudes and with velocities that depend on the feature's dominant frequency. In a given waveform, high-frequency features generally arrive earlier than low-frequency features, typical for normal mode propagation. To analyze these waveforms,...

Silver Lake is typically an oligotrophic-to-mesotrophic, soft-water, terminal lake in northwestern Wisconsin. A terminal lake is a closed-basin lake with surface-water inflows but no surface-water outflows to other water bodies. After several years with above-normal precipitation, very high water levels caused flooding of several buildings near the lake and erosion...

Fifty years of U.S. Geological Survey (USGS) research on glacier change shows recent dramatic shrinkage of glaciers in three climatic regions of the United States. These long periods of record provide clues to the climate shifts that may be driving glacier change. The USGS Benchmark Glacier Program began in 1957...

Over the past century, Laysan (Phoebastria immutabilis) and black-footed (Phoebastria nigripes) albatrosses have been subjected to high rates of mortality and disturbance at the breeding colonies and at sea. Populations were greatly reduced and many colonies were extirpated around the turn of the 20th century as a result of feather...

Within minutes of a significant earthquake anywhere on the globe, the U.S. Geological Survey (USGS) Prompt Assessment of Global Earthquakes for Response (PAGER) system assesses its potential societal impact. PAGER automatically estimates the number of people exposed to severe ground shaking and the shaking intensity at affected cities. Accompanying maps...

Mark Twain raved about the Mississippi River basin as, 'the body of the Nation'. The 'upper body', upstream of the confluence with the Ohio River, includes commercially navigable reaches and branching tributaries that are recreationally and environmentally important. Together they feed and shelter an array of fish and wildlife in...

This chapter focuses on the methodology for determining whether observed sediment deformation had a seismic shaking or a nonseismic origin. The chapter emphasizes features developed from the process of liquefaction, which is the transformation of a granular material from a solid state into a liquefied state as a consequence of increased pore-water pressure. Geophysical methods including electrical...

This presentation covers three general topics: (1) description of a new geologic compilation of the United States that shows the location of magnesium-rich ultramafic rocks in the conterminous United States; (2) conceptual illustration of the potential ways that ultramafic rocks could be used to sequester carbon dioxide; and (3) description...

Because of water quantity and quality concerns within the Ozark aquifer, the State of Kansas in 2004 issued a moratorium on most new appropriations from the aquifer until results were made available from a cooperative study between the U.S. Geological Survey and the Kansas Water Office. The purposes of the...

Mallard (Anas platyrhynchos) populations in the lower Mississippi Alluvial Valley (LMAV), USA, historically averaged 1.6 million and represented the largest concentrations of wintering mallards in North America. Effective management of this wintering population requires current information on use of habitats. Accordingly, we employed radiotelemetry techniques to assess proportional use of...

The complexity of ecosystems and mechanisms of succession are often simplified by linear and mathematical models used to understand and predict system behavior. Such models often do not incorporate multivariate, nonlinear feedbacks in pattern and process that include multiple scales of organization inherent within real-world...

West Virginia's crayfishes have received moderate attention since publication of Jezerinac et al.'s (1995) monograph of the state fauna. Survey efforts were initiated over the summers of 2006 and 2007 to gather voucher material for the Indiana Biological Survey's Crustacean Collection. These collections have provided new information regarding the...

Gas, oil, and water production data were collected from the Fuller Reservoir, Cooper Reservoir, Frenchie Draw, Cave Gulch, and Madden fields in the Wind River Basin, Wyoming. These fields produce from the Mississippian Madison Limestone, the Upper Cretaceous Cody Shale and Mesaverde Formation, and the Paleocene lower unnamed member and...

Gravity and aeromagnetic data provide the underpinnings of a hydrogeologic framework for the Mojave National Preserve by estimating the thickness of Cenozoic deposits and locating inferred structural features that influence groundwater flow. An inversion of gravity data indicates that thin (<1 km) basin deposits cover much of the Preserve, except...

Characterization of infectious haematopoietic necrosis virus (IHNV) field isolates from North America has established three main genogroups (U, M and L) that differ in host-specific virulence. In sockeye salmon, Oncorhynchus nerka, the U genogroup is highly virulent, whereas the M genogroup is nearly non-pathogenic. In this study, we sought to...

Four geologic provinces of the Barents Sea shelf were assessed for undiscovered crude oil, natural gas, and natural gas liquid or condensate resources as part of the U.S. Geological Survey's Circum-Arctic Oil and Gas Resource Appraisal. Using a geology-based methodology, the mean undiscovered, conventional, technically recoverable petroleum resources in the...

This issue showcases some good work from Chinese authors who attended the International Workshop of Earth Observation and Remote Sensing Applications (EORSA), held in Beijing, China, June 30-July 2, 2008. The five articles in this issue focus on remote sensing of regional land use and land cover....

The Cretaceous/Tertiary (K/T) boundary corresponds to one of the very few unique events in the geological record discovered to date, representing a single traceable timeline across the world. This timeline, coincident with the geochemical and mineralogical singularities caused by the impact of a large extraterrestrial body, is also coincident with the end-Cretaceous extinction event in North America. This precise timeline gives...

California's Central Valley covers about 20,000 square miles and is one of the most productive agricultural regions in the world. More than 250 different crops are grown in the Central Valley with an estimated value of $17 billion per year. This irrigated agriculture relies heavily on surface-water diversions and groundwater...

The U.S. Geological Survey, Water Resources, in cooperation with Federal, State, and local agencies, obtains a large amount of data pertaining to the groundwater resources of California each water year (October 1-September 30). These data constitute a valuable database for developing an improved understanding of the water resources of the...

An investigation into groundwater/surface-water interactions in four tributary subbasins of the Okanogan River determined that streamflows and shallow groundwater levels beneath the streams varied seasonally and by location. Streamflows measured in June 2008 indicated net losses of streamflow along 10 of 17 reaches, and hydraulic gradients measured between streams and...