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Conceptual model for invasive bivalve control on wetland productivity
Rosemary Hartman, Larry R. Brown, Janet K. Thompson, Francis Parchaso
2017, Interagency Ecological Program Technical Report 91
Tidal wetlands were the historically dominant features of many coastal regions around the world, including the San Francisco Estuary (Callaway et al. 2011; Whipple et al. 2012). These mosaics of varied interconnected habitats (Mitsch and Gosselink 1993) provide a host of ecosystem services, including biodiversity maintenance, fish and wildlife habitat,...
Refining the formation and early evolution of the Eastern North American Margin: New insights from multiscale magnetic anomaly analyses
John A. Greene, Masako Tominaga, Nathaniel C. Miller, Deborah Hutchinson, Matthew R. Karl
2017, Journal of Geophysical Research B: Solid Earth (122) 8724-8748
To investigate the oceanic lithosphere formation and early seafloor spreading history of the North Atlantic Ocean, we examine multiscale magnetic anomaly data from the Jurassic/Early Cretaceous age Eastern North American Margin (ENAM) between 31 and 40°N. We integrate newly acquired sea surface magnetic anomaly and seismic reflection data with publicly...
Monitoring the welfare of polar bear populations in a rapidly changing Arctic
Todd C. Atwood, Colleen G. Duncan, Kelly A. Patyk, Sarah A. Sonsthagen
2017, Book chapter, Marine mammal welfare
Most programs for monitoring the welfare of wildlife populations support efforts aimed at reaching discrete management objectives, like mitigating conflict with humans. While such programs can be effective, their limited scope may preclude systemic evaluations needed for large-scale conservation initiatives, like the recovery of at-risk species. We discuss select categories...
Concepts and practices: Estimating abundance of prey species using hierarchical model-based approaches
Robert Dorazio, N. Samba Kumar, J. Andrew Royle, Arjun M. Gopalaswamy
2017, Book chapter, Methods for monitoring tiger and prey populations
Tigers predominantly prey on large ungulate species, such as sambar (Cervus unicolor), red deer (Cervus elaphus), gaur (Bos gaurus), banteng (Bos javanicus), chital (Axis axis), muntjac (Muntiacus muntjak), wild pig (Sus scrofa), and bearded pig (Sus barbatus). The density of a tiger population is strongly correlated with the density of...
Human-polar bear interactions in a changing Arctic: Existing and emerging concerns
Todd C. Atwood, Kristin S. Simac, Stewart Breck, Geoff York, James Wilder
2017, Book chapter, Marine mammal welfare
The behavior and sociality of polar bears (Ursus maritimus) have been shaped by evolved preferences for sea ice habitat and preying on marine mammals. However, human behavior is causing changes to the Arctic marine ecosystem through the influence of greenhouse gas emissions that drive long-term change in ecosystem...
Implications of rapid environmental change for polar bear behavior and sociality
Todd C. Atwood
2017, Book chapter, Marine mammal welfare
Historically, the Arctic sea ice has functioned as a structural barrier that has limited the nature and extent of interactions between humans and polar bears (Ursus maritimus). However, declining sea ice extent, brought about by global climate change, is increasing the potential for human-polar bear interactions. Loss of...
Combining remote sensing and water-balance evapotranspiration estimates for the conterminous United States
Meredith Reitz, Gabriel B. Senay, Ward E. Sanford
2017, Remote Sensing (9)
Evapotranspiration (ET) is a key component of the hydrologic cycle, accounting for ~70% of precipitation in the conterminous U.S. (CONUS), but it has been a challenge to predict accurately across different spatio-temporal scales. The increasing availability of remotely sensed data has led to significant advances in the frequency and spatial...
Bacterial sulfur disproportionation constrains timing of neoproterozoic oxygenation
Marcus Kunzmann, Thi Hao Bui, Peter W. Crockford, Galen P. Halverson, Clint Scott, Timothy W. Lyons, Boswell A. Wing
2017, Geology (45) 207-210
Various geochemical records suggest that atmospheric O2 increased in the Ediacaran (635–541 Ma), broadly coincident with the emergence and diversification of large animals and increasing marine ecosystem complexity. Furthermore, geochemical proxies indicate that seawater sulfate levels rose at this time too, which has been hypothesized to reflect increased sulfide oxidation in...
Constraining the magmatic system at Mount St. Helens (2004–2008) using Bayesian inversion with physics-based models including gas escape and crystallization
Ying-Qi Wong, Paul Segall, Andrew Bradley, Kyle R. Anderson
2017, Journal of Geophysical Research B: Solid Earth (122) 7789-7812
Physics-based models of volcanic eruptions track conduit processes as functions of depth and time. When used in inversions, these models permit integration of diverse geological and geophysical data sets to constrain important parameters of magmatic systems. We develop a 1-D steady state conduit model for effusive eruptions including equilibrium crystallization...
EROD activity, chromosomal damage, and oxidative stress in response to contaminants exposure in tree swallow (Tachycineta bicolor) nestlings from Great Lakes Areas of Concern
Thomas W. Custer, Christine M. Custer, Paul M. Dummer, Emilie Bigorgne, Elias Oziolor, Natalie K. Karouna-Renier, Sandra L. Schultz, Richard A. Erickson, Kevin Aagaard, Cole W. Matson
2017, Ecotoxicology (26) 1392-1407
Tree swallow, Tachycineta bicolor, nestlings were collected from 60 sites in the Great Lakes, which included multiple sites within 27 Areas of Concern (AOCs) and six sites not listed as AOCs from 2010 to 2014. Nestlings, approximately 12 days-of-age, were evaluated for ethoxyresorufin-O-dealkylase (EROD) activity, chromosomal damage, and six measures...
Progress and lessons learned from water-quality monitoring networks
Donna N. Myers, Amy S. Ludtke
2017, Book chapter, The science behind sustaining the world's most crucial resource
Stream-quality monitoring networks in the United States were initiated and expanded after passage of successive federal water-pollution control laws from 1948 to 1972. The first networks addressed information gaps on the extent and severity of stream pollution and served as early warning systems for spills. From 1965 to 1972, monitoring...
Polar bears, Ursus maritimus
Karyn D. Rode, Ian Stirling
2017, Book chapter, Encyclopedia of marine mammals
Polar bears are the largest of the eight species of bears found worldwide and are covered in a pigment-free fur giving them the appearance of being white. They are the most carnivorous of bear species consuming a high-fat diet, primarily of ice-associated seals and other marine mammals. They...
Procedure for calculating estimated ultimate recoveries of wells in the Mississippian Barnett Shale, Bend Arch–Fort Worth Basin Province of north-central Texas
Heidi M. Leathers-Miller
2017, Scientific Investigations Report 2017-5102
In 2015, the U.S. Geological Survey published an assessment of technically recoverable continuous oil and gas resources of the Mississippian Barnett Shale in the Bend Arch–Fort Worth Basin Province of north-central Texas. Of the two assessment units involved in the overall assessment, one included a roughly equal number of oil wells and gas wells...
Late Quaternary fluvial history of Santa Cruz Island, California, USA
R. Randall Schumann, Jeffrey S. Pigati
2017, Western North American Naturalist (78) 511-529
The geologic history of fluvial systems on Santa Cruz Island (SCI) is complex, involving responses to both allogenic and autogenic forcings. During periods of low or lowering sea level, canyons on the island were eroded and sediment was transported off the island onto the exposed marine shelf. When sea level...
Flood runoff in relation to water vapor transport by atmospheric rivers over the western United States, 1949–2015
Christopher P. Konrad, Michael D. Dettinger
2017, Geophysical Research Letters (44) 11456-11462
Atmospheric rivers (ARs) have a significant role in generating floods across the western United States. We analyze daily streamflow for water years 1949 to 2015 from 5,477 gages in relation to water vapor transport by ARs using a 6 h chronology resolved to 2.5° latitude and longitude. The probability that an...
Distribution of foraminifera in Chincoteague Bay and the marshes of Assateague Island and the adjacent vicinity, Maryland and Virginia
Alisha M. Ellis, Jaimie Shaw, Lisa E. Osterman, Christopher G. Smith
2017, Data Series 1060
Scientists from the U.S. Geological Survey (USGS), St. Petersburg Coastal and Marine Science Center conducted a seasonal collection of estuarine, marsh, and sandy washover surface sediments from Chincoteague Bay, Tom’s Cove, and the surrounding Assateague Island and Delmarva Peninsula in March–April and October 2014, after Hurricane Sandy. Micropaleontology samples were...
A seasonal and spatial comparison of metals, and stable carbon and nitrogen isotopes, in Chincoteague Bay and the marsh deposits of Assateague Island and the adjacent vicinity, Maryland and Virginia
Alisha M. Ellis, Christopher G. Smith
2017, Data Series 1059
After Hurricane Sandy, scientists from the U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center conducted a seasonal collection of estuarine, marsh, and sandy overwash surface sediments from Chincoteague Bay, Tom’s Cove, and the surrounding Assateague Island and Delmarva Peninsula in March–April and October 2014. Surplus surface sediment was...
Solid-phase arsenic speciation in aquifer sediments: A micro-X-ray absorption spectroscopy approach for quantifying trace-level speciation
Sarah L. Nicholas, Melinda L. Erickson, Laurel G. Woodruff, Alan R. Knaeble, Matthew A. Marcus, Joshua K. Lynch, Brandy M. Toner
2017, Geochimica et Cosmochimica Acta (211) 228-255
e of this research is to identify the solid-phase sources and geochemical mechanisms of release of As in aquifers of the Des Moines Lobe glacial advance. The overarching concept is that conditions present at the aquifer-aquitard interfaces promote a suite of geochemical reactions leading to mineral alteration and release of...
Estimating rupture distances without a rupture
Eric M. Thompson, Charles Worden
2017, Bulletin of the Seismological Society of America (10) 1-9
Most ground motion prediction equations (GMPEs) require distances that are defined relative to a rupture model, such as the distance to the surface projection of the rupture (RJB) or the closest distance to the rupture plane (RRUP). There are a number of situations in which GMPEs are used where it...
The value of information for woodland management: Updating a state–transition model
William K. Morris, Michael C. Runge, Peter A. Vesk
2017, Ecosphere (8) 1-12
Value of information (VOI) analyses reveal the expected benefit of reducing uncertainty to a decision maker. Most ecological VOI analyses have focused on population models rarely addressing more complex community models. We performed a VOI analysis for a complex state–transition model of Box-Ironbark Forest and Woodland management. With three management...
Determining fine-scale use and movement patterns of diving bird species in federal waters of the Mid-Atlantic United States using satellite telemetry
Caleb Spiegel, Alicia Berlin, Andrew Gilbert, Carrie E. Gray, William Montevecchi, Iain Stenhouse, Scott Ford, Glenn H. Olsen, Jonathan Fiely, Lucas Savoy, M. Wing Goodale, Chantelle Burke
2017, Report
Offshore wind energy development in the United States is projected to expand in the upcoming decades to meet growing energy demands and reduce fossil fuel emissions. There is particular interest in commercial offshore wind development within Federal waters (i.e., > 3 nautical miles from shore) of the mid-Atlantic. In order...
Estimating virus occurrence using Bayesian modeling in multiple drinking water systems of the United States
Eunice A. Varughese, Nichole E Brinkman, Emily M Anneken, Jennifer S Cashdollar, G. Shay Fout, Edward T. Furlong, Dana W. Kolpin, Susan T. Glassmeyer, Scott P Keely
2017, Science of the Total Environment (619-620) 1330-1339
Drinking water treatment plants rely on purification of contaminated source waters to provide communities with potable water. One group of possible contaminants are enteric viruses. Measurement of viral quantities in environmental water systems are often performed using polymerase chain reaction (PCR) or quantitative PCR (qPCR). However, true values may be...
Regionalizing indicators for marine ecosystems: Bering Sea–Aleutian Island seabirds, climate, and competitors
William J. Sydeman, Sarah Ann Thompson, John F. Piatt, Marisol García-Reyes, Stephani Zador, Jeffrey C. Williams, Marc Romano, Heather Renner
2017, Ecological Indicators (78) 458-469
Seabirds are thought to be reliable, real-time indicators of forage fish availability and the climatic and biotic factors affecting pelagic food webs in marine ecosystems. In this study, we tested the hypothesis that temporal trends and interannual variability in seabird indicators reflect simultaneously occurring bottom-up (climatic) and competitor (pink salmon) forcing of food...
Spatially explicit dynamic N-mixture models
Qing Zhao, J. Andrew Royle, G. Scott Boomer
2017, Population Ecology (59) 293-300
Knowledge of demographic parameters such as survival, reproduction, emigration, and immigration is essential to understand metapopulation dynamics. Traditionally the estimation of these demographic parameters requires intensive data from marked animals. The development of dynamic N-mixture models makes it possible to estimate demographic parameters from count data of unmarked animals, but...