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Low-altitude photographic transects of the Arctic Network of National Park Units and Selawik National Wildlife Refuge, Alaska, July 2013
Bruce G. Marcot, M. Torre Jorgenson, Anthony R. DeGange
2014, Data Series 846
During July 16–18, 2013, low-level photography flights were conducted (with a Cessna 185 with floats and a Cessna 206 with tundra tires) over the five administrative units of the National Park Service Arctic Network (Bering Land Bridge National Preserve, Cape Krusenstern National Monument, Gates of the Arctic National Park and...
Fuzzy boundaries: color and gene flow patterns among parapatric lineages of the western shovel-nosed snake and taxonomic implication
Dustin A. Wood, Robert N. Fisher, Amy G. Vandergast
2014, PLoS ONE (9)
Accurate delineation of lineage diversity is increasingly important, as species distributions are becoming more reduced and threatened. During the last century, the subspecies category was often used to denote phenotypic variation within a species range and to provide a framework for understanding lineage differentiation, often considered incipient speciation. While this...
Unsaturated flow characterization utilizing water content data collected within the capillary fringe
Arthur Baehr, Timothy J. Reilly
2014, Air, Soil and Water Research (7) 47-52
An analysis is presented to determine unsaturated zone hydraulic parameters based on detailed water content profiles, which can be readily acquired during hydrological investigations. Core samples taken through the unsaturated zone allow for the acquisition of gravimetrically determined water content data as a function of elevation at 3 inch intervals....
Landscape selection by piping plovers has implications for measuring habitat and population size
Michael J. Anteau, Terry L. Shaffer, Mark T. Wiltermuth, Mark H. Sherfy
2014, Landscape Ecology (29) 1033-1044
How breeding birds distribute in relation to landscape-scale habitat features has important implications for conservation because those features may constrain habitat suitability. Furthermore, knowledge of these associations can help build models to improve area-wide demographic estimates or to develop a sampling stratification for research and monitoring. This is particularly important...
The USGS National Streamflow Information Program and the importance of preserving long-term streamgages
Glenn A. Hodgkins, J. Michael Norris, Robert M. Lent
2014, Fact Sheet 2014-3026
Long-term streamflow information is critical for use in several water-related areas that are important to humans and wildlife, including water management, computation of flood and drought flows for water infrastructure, and analysis of climate-related trends. Specific uses are many and diverse and range from informing water rights across state and...
Hydrogeology and water quality of the Nanticoke Creek stratified-drift aquifer, near Endicott, New York
Elizabeth A. Kreitinger, William M. Kappel
2014, Scientific Investigations Report 2014-5063
The Village of Endicott, New York, is seeking an alternate source of public drinking water with the potential to supplement their current supply, which requires treatment due to legacy contamination. The southerly-draining Nanticoke Creek valley, located north of the village, was identified as a potential water source and the local...
Water resources of De Soto Parish, Louisiana
Lawrence B. Prakken, Vincent E. White
2014, Fact Sheet 2013-3107
Information concerning the availability, use, and quality of water in De Soto Parish, Louisiana, is critical for proper water-supply management. The purpose of this fact sheet is to present information that can be used by water managers, parish residents, and others for stewardship of this vital resource. Information on the...
Three-dimensional seismic velocity structure and earthquake relocations at Katmai, Alaska
Rachel Murphy, Clifford Thurber, Stephanie G. Prejean, Ninfa Bennington
2014, Journal of Volcanology and Geothermal Research (276) 121-131
We invert arrival time data from local earthquakes occurring between September 2004 and May 2009 to determine the three-dimensional (3D) upper crustal seismic structure in the Katmai volcanic region. Waveforms for the study come from the Alaska Volcano Observatory's permanent network of 20 seismic stations in the area (predominantly single-component,...
Seismicity and seismic structure at Okmok Volcano, Alaska
Summer J. Ohlendorf, Clifford H. Thurber, Jeremy D. Pesicek, Stephanie G. Prejean
2014, Journal of Volcanology and Geothermal Research (278-279) 103-119
Okmok volcano is an active volcanic caldera located on the northeastern portion of Umnak Island in the Aleutian arc, with recent eruptions in 1997 and 2008. The Okmok area had ~900 locatable earthquakes between 2003 and June 2008, and an additional ~600 earthquakes from the beginning of the 2008 eruption...
Accuracy assessment of the U.S. Geological Survey National Elevation Dataset, and comparison with other large-area elevation datasets: SRTM and ASTER
Dean B. Gesch, Michael J. Oimoen, Gayla A. Evans
2014, Open-File Report 2014-1008
The National Elevation Dataset (NED) is the primary elevation data product produced and distributed by the U.S. Geological Survey. The NED provides seamless raster elevation data of the conterminous United States, Alaska, Hawaii, U.S. island territories, Mexico, and Canada. The NED is derived from diverse source datasets that are processed...
The search for geologic evidence of distant-source tsunamis using new field data in California
Rick Wilson, Eileen Hemphill-Haley, Bruce Jaffe, Bruce Richmond, Robert Peters, Nick Graehl, Harvey Kelsey, Robert Leeper, Steve Watt, Mary McGann, Don F. Hoirup, Catherine Chague-Goff, James Goff, Dylan Caldwell, Casey Loofbourrow
2014, Open-File Report 2013-1170-C
A statewide assessment for geological evidence of tsunamis, primarily from distant-source events, found tsunami deposits at several locations, though evidence was absent at most locations evaluated. Several historical distant-source tsunamis, including the 1946 Aleutian, 1960 Chile, and 1964 Alaska events, caused inundation along portions of the northern and central California...
Impacts of white-tailed deer on red trillium (Trillium recurvatum): defining a threshold for deer browsing pressure at the Indiana Dunes National Lakeshore
Noel B. Pavlovic, Stacey A. Leicht-Young, Ralph Grundel
2014, Scientific Investigations Report 2014-5070
Overabundant white-tailed deer (Odocoileus virginianus) have been a concern for land managers in eastern North America because of their impacts on native forest ecosystems. Managers have sought native plant species to serve as phytoindicators of deer impacts to supplement deer surveys. We analyzed experimental data about red trillium (Trillium recurvatum),...
Post-earthquake relaxation using a spectral element method: 2.5-D case
Frederick Pollitz
2014, Geophysical Journal International (198) 308-326
The computation of quasi-static deformation for axisymmetric viscoelastic structures on a gravitating spherical earth is addressed using the spectral element method (SEM). A 2-D spectral element domain is defined with respect to spherical coordinates of radius and angular distance from a pole of symmetry, and 3-D viscoelastic structure is assumed...
Geochemical and mineralogical maps for soils of the conterminous United States
David B. Smith, William F. Cannon, Laurel G. Woodruff, Federico Solano, Karl J. Ellefsen
2014, Open-File Report 2014-1082
The U.S. Geological Survey began sampling in 2007 for a low-density (1 site per 1,600 square kilometers, 4,857 sites) geochemical and mineralogical survey of soils in the conterminous United States as part of the North American Soil Geochemical Landscapes Project. The sampling protocol for the national-scale survey included, at each...
Creating a monthly time series of the potentiometric surface in the Upper Floridan aquifer, Northern Tampa Bay area, Florida, January 2000-December 2009
Terrie M. Lee, Geoffrey G. Fouad
2014, Scientific Investigations Report 2014-5038
In Florida’s karst terrain, where groundwater and surface waters interact, a mapping time series of the potentiometric surface in the Upper Floridan aquifer offers a versatile metric for assessing the hydrologic condition of both the aquifer and overlying streams and wetlands. Long-term groundwater monitoring data were used to generate a...
An individual-based growth and competition model for coastal redwood forest restoration
Phillip J. van Mantgem, Adrian J. Das
2014, Canadian Journal of Forest Research (44) 1051-1057
Thinning treatments to accelerate coastal redwood forest stand development are in wide application, but managers have yet to identify prescriptions that might best promote Sequoia sempervirens (Lamb. ex D. Don) Endl. (redwood) growth. The creation of successful thinning prescriptions would be aided by identifying the underlying mechanisms governing how individual tree growth...
Freshwater availability and coastal wetland foundation species: ecological transitions along a rainfall gradient
Michael J. Osland, Nicholas M. Enwright, Camille L. Stagg
2014, Ecology (95) 2789-2802
Climate gradient-focused ecological research can provide a foundation for better understanding critical ecological transition points and nonlinear climate-ecological relationships, which is information that can be used to better understand, predict, and manage ecological responses to climate change. In this study, we examined the influence of freshwater availability upon the coverage...
Beach science in the Great Lakes
Meredith B. Nevers, Murulee N. Byappanahalli, Thomas A. Edge, Richard L. Whitman
2014, Journal of Great Lakes Research (40) 1-14
Monitoring beach waters for human health has led to an increase and evolution of science in the Great Lakes, which includes microbiology, limnology, hydrology, meteorology, epidemiology, and metagenomics, among others. In recent years, concerns over the accuracy of water quality standards at protecting human health have led to a significant...
Home range characteristics of Mexican Spotted Owls in the Rincon Mountains, Arizona
David W. Willey, Charles van Riper III
2014, Wilson Journal of Ornithology (126) 53-59
We studied a small isolated population of Mexican Spotted Owls (Strix occidentalis lucida) from 1996–1997 in the Rincon Mountains of Saguaro National Park, southeastern Arizona, USA. All mixed-conifer and pine-oak forest patches in the park were surveyed for Spotted Owls, and we located, captured, and radio-tagged 10 adult birds representing...
The distribution and extent of heavy metal accumulation in song sparrows along Arizona's upper Santa Cruz River
Michael B. Lester, Charles van Riper III
2014, Environmental Monitoring and Assessment (186) 4779-4791
Heavy metals are persistent environmental contaminants, and transport of metals into the environment poses a threat to ecosystems, as plants and wildlife are susceptible to long-term exposure, bioaccumulation, and potential toxicity. We investigated the distribution and cascading extent of heavy metal accumulation in southwestern song sparrows (Melospiza melodia fallax), a...
Factors affecting public-supply well vulnerability in two karst aquifers
MaryLynn Musgrove, Brian G. Katz, Lynne S. Fahlquist, Christy A. Crandall, Richard J. Lindgren
2014, Ground Water (52) 63-75
Karst aquifers occur in a range of climatic and geologic settings. Nonetheless, they are commonly characterized by their vulnerability to water-quality impairment. Two karst aquifers, the Edwards aquifer in south-central Texas and the Upper Floridan aquifer in western Florida, were investigated to assess factors that control the movement of contaminants...
Mercury concentrations in water, and mercury and selenium concentrations in fish from Brownlee Reservoir and selected sites in Boise and Snake Rivers, Idaho and Oregon, 2013
Dorene E. MacCoy
2014, Open-File Report 2014-1099
Mercury (Hg) analyses were conducted on samples of sport fish and water collected from six sampling sites in the Boise and Snake Rivers, and Brownlee Reservoir to meet National Pollution Discharge and Elimination System (NPDES) permit requirements for the City of Boise, Idaho. A water sample was collected from each...
Sea otters are recolonizing southern California in fits and starts
Kevin D. Lafferty, M. Tim Tinker
2014, Ecosphere (5)
After near extinction as a result of the fur trade in the 1700s and 1800s, the southern sea otter slowly reoccupied the core of its range in central California. Range expansion beyond central California is seen as key to full recovery of otters, but the rate of expansion has been...
Cruise report for P1-13-LA, U.S. Geological Survey gas hydrates research cruise, R/V Pelican April 18 to May 3, 2013, deepwater Gulf of Mexico
Seth S. Haines, Patrick E. Hart, Carolyn Ruppel, Thomas O'Brien, Wayne Baldwin, Jenny White, Eric Moore, Peter Dal Ferro, Peter Lemmond
2014, Open-File Report 2014-1080
The U.S. Geological Survey led a seismic acquisition cruise in the Gulf of Mexico from April 18 to May 3, 2013, with the objectives of (1) achieving improved imaging and characterization at two established gas hydrate study sites, and (2) refining geophysical methods for gas hydrate characterization in other locations....
Bathymetry and acoustic backscatter: outer mainland shelf and slope, Gulf of Santa Catalina, southern California
Peter Dartnell, James E. Conrad, Holly F. Ryan, David P. Finlayson
2014, Open-File Report 2014-1094
In 2010 and 2011, scientists from the U.S. Geological Survey (USGS), Coastal and Marine Geology Program, acquired bathymetry and acoustic-backscatter data from the outer shelf and slope region offshore of southern California. The surveys were conducted as part of the USGS Marine Geohazards Program. Assessment of the hazards posed by...