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Boa constrictor is a wide ranging snake species that is common in the pet trade and is currently listed in CITES Appendix II. Hog Island boas, or Cayos Cochinos boas, are a dwarf, insular race of Boa constrictor imperator endemic to the Cayos Cochinos Archipelago, Honduras. Cayos Cochinos boas are...

A remarkable increase in seismic activity in Oklahoma since 2009 has been shown to correlate closely with enhanced hydrocarbon extraction and associated wastewater disposal; 99% of this recent Oklahoma earthquake activity has occurred within 15 km of a call II injection well (Ellsworth, 2013). In response to this increase in seismic activity,...

The hybrid cyclone-nor’easter known as Hurricane Sandy affected the mid-Atlantic and northeastern United States during October 28-30, 2012, causing extensive coastal flooding. Prior to storm landfall, the U.S. Geological Survey (USGS) deployed a temporary monitoring network from Virginia to Maine to record the storm tide and coastal flooding generated by...

A number of researchers have attempted to estimate salmonid smolt survival during outmigration through an estuary. However, it is currently unclear how the design of such studies influences the accuracy and precision of survival estimates. In this simulation study we consider four patterns of smolt survival probability in the estuary,...

The U.S. Geological Survey (USGS) conducts baseline and storm response photography missions to document and understand the changes in vulnerability of the Nation's coasts to extreme storms. On September 17, 2004, the USGS conducted an oblique aerial photographic survey from Crawfordville, Florida, to Petit Bois Island, Mississippi aboard a Piper...

Digital flood-inundation maps for a 6-mile reach of the Hohokus Brook in New Jersey from White's Lake Dam in Waldwick Borough, through Ho-Ho-Kus Borough to Grove Street in the Village of Ridgewood were created by the U.S. Geological Survey (USGS) in cooperation with the New Jersey Department of Environmental Protection....

In August of 2013, the U.S. Geological Survey conducted a geophysical survey offshore of Petit Bois Island, Mississippi. This effort was part of the U.S. Geological Survey Gulf of Mexico Science Coordination partnership with the U.S. Army Corps of Engineers to assist the Mississippi Coastal Improvements Program and the Northern...

Questions Do abiotic environmental filters or time-since-fire (TSF) explain more variability in post-fire vegetation assembly? Do these influences vary between vegetation structure and composition, and across spatial scales? Location Sonoran Desert of southwestern Arizona, US. Methods We measured perennial vegetation in a chronosequence of 13 fires (8-33 yr TSF) spanning a broad regional gradient. The...

The U.S. Geological Survey, in cooperation with the Shoshone-Paiute Tribes of the Duck Valley Indian Reservation, analyzed mercury (Hg) concentration in rainbow trout (Oncorhynchus mykiss) collected from three reservoirs on the reservation (Mountain View, Lake Billy Shaw, and Sheep Creek) during sampling events in 2007, 2009, and 2013, to determine...

Stakeholders and water-resource managers in Lincoln County, New Mexico, have had long-standing concerns over the impact of population growth and groundwater withdrawals. These concerns have been exacerbated in recent years by extreme drought conditions and two major wildfires in the upper Rio Hondo Basin, located in south-central New Mexico. The...

Despite the ubiquity of Mn oxides in natural environments, there are only a few observations of biological Mn(II) oxidation at pH < 6. The lack of low pH Mn-oxidizing bacteria (MOB) isolates limits our understanding of how pH influences biological Mn(II) oxidation in extreme environments. Here, we report that a...

Triggered seismicity arising from dynamic stresses is often explained by the Mohr-Coulomb failure criterion, where elevated pore pressures reduce the effective strength of faults in fluid-saturated rock. The seismic response of a fluid-rock system naturally depends on its hydro-mechanical properties, but accurately assessing how pore-fluid pressure responds to applied stress...

As part of a larger study, the U.S. Geological Survey undertook a study to identify the potential for phosphate deposits in Afghanistan. As part of this study, a geographic information system was constructed containing a database of phosphate occurrences in Afghanistan and adjacent countries, and a database of potential host...

The United States is one of eight Arctic nations responsible for the stewardship of a polar region undergoing dramatic environmental, social, and economic changes. Although warming and cooling cycles have occurred over millennia in the Arctic region, the current warming trend is unlike anything recorded previously and is affecting the...

Groundwater withdrawals have caused saltwater to encroach into freshwater-bearing aquifers beneath Baton Rouge, Louisiana. The 10 aquifers beneath the Baton Rouge area, which includes East and West Baton Rouge Parishes, Pointe Coupee Parish, and East and West Feliciana Parishes, provided about 184.3 million gallons per day (Mgal/d) for public supply...

This Data Series summarizes results from July 2013 sampling in the western Alaska Range near Mount Estelle, Alaska. The fieldwork combined in situ and camp-based spectral measurements of talus/soil and rock samples. Five rock and 48 soil samples were submitted for quantitative geochemi­cal analysis (for 55 major and trace elements),...

During October 2012 through March 2013, the U.S. Geological Survey (USGS), in cooperation with the U.S. Environmental Protection Agency (EPA) Region 4, Superfund Section, conducted borehole geophysical logging, surface geophysical surveys, and water-quality profiling in selected wells and areas to characterize or delineate the extent of elevated subsurface electrical conductivity...

Floodplains are vital to the structure and function of river-floodplain ecosystems. Among the many ecological services provided by floodplains are nutrient cycling and seasonal habitats for fish, including spawning, nursery, foraging and wintering habitats. Connections between the river channel and floodplain habitats are essential to realize these ecological services, but...

The risks to safe and efficient air travel from volcanic-ash hazards are well documented and widely recognized. Under the aegis of the International Civil Aviation Organization, globally coordinated mitigation procedures are in place to report explosive eruptions, detect airborne ash clouds and forecast their expected movement, and issue specialized messages...

The transition from seamount to oceanic island typically involves surtseyan volcanism. However, the geological record at many islands in the NE Atlantic—all located within the slow-moving Nubian plate—does not exhibit evidence for an emergent surtseyan phase but rather an erosive unconformity between the submarine basement and the overlying subaerial shield...

What controls the architecture of drainage networks is a fundamental question in geomorphology. Recent work has elucidated the mechanisms of drainage network development in steadily uplifting landscapes, but the controls on drainage-network morphology in transient landscapes are relatively unknown. In this paper we exploit natural experiments in drainage network development...

This pilot study explores the potential of using low-resolution (0.2 points/m2) airborne laser scanning (ALS)-derived elevation data to model stream rating curves. Rating curves, which allow the functional translation of stream water depth into discharge, making them integral to water resource monitoring efforts, were modeled using a physics-based approach that...

Morphodynamic data assimilation blends observations with model predictions and comes in many forms, including linear regression, Kalman filter, brute-force parameter estimation, variational assimilation, and Bayesian analysis. Importantly, data assimilation can be used to identify sources of prediction errors that lead to improved fundamental understanding. Overall, models incorporating data assimilation yield...

Despite their utility for prediction of coastal behavior and for coastal management, littoral sediment budgets are difficult to quantify over large regions of coastline and over short time scales. In this study, bathymetric change analysis shows differences in the magnitude and spatial location of erosion and accretion over three years;...

Closure of Glen Canyon Dam in 1963 dramatically changed discharge and sediment supply to the downstream Colorado River in Marble and Grand Canyons. Magnitudes of seasonal flow variation have been suppressed, while daily fluctuations have increased because of hydropower generation. Lake Powell, the upstream reservoir, traps all sediment, leaving the...