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Publication Extents

Not all publications have extents, not all extents are completely accurate
Phenological response of an Arizona dryland forest to short-term climatic extremes
Jessica J. Walker, Kirsten de Beurs, Randolph Wynne
2015, Remote Sensing (7) 10832-10855
Baseline information about dryland forest phenology is necessary to accurately anticipate future ecosystem shifts. The overarching goal of our study was to investigate the variability of vegetation phenology across a dryland forest landscape in response to climate alterations. We analyzed the influence of site characteristics and climatic conditions on the...
Estimating bighorn sheep (Ovis canadensis) abundance using noninvasive sampling at a mineral lick within a National Park Wilderness Area
Kathryn A. Schoenecker, Mary Kay Watry, Laura E. Ellison, Michael A. Schwarz, Gordon Luikart
2015, Western North American Naturalist (75) 181-191
Conservation of species requires accurate population estimates. We used genetic markers from feces to determine bighorn sheep abundance for a herd that was hypothesized to be declining and in need of population status monitoring. We sampled from a small but accessible portion of the population's range where animals naturally congregate...
Analysis and selection of magnitude relations for the Working Group on Utah Earthquake Probabilities
Christopher DuRoss, Susan Olig, David Schwartz
2015, Conference Paper, Basin and Range Province Seismic Hazards Summit III, Utah Geological Survey Miscellaneous Publication 15-5
Prior to calculating time-independent and -dependent earthquake probabilities for faults in the Wasatch Front region, the Working Group on Utah Earthquake Probabilities (WGUEP) updated a seismic-source model for the region (Wong and others, 2014) and evaluated 19 historical regressions on earthquake magnitude (M). These regressions relate M to fault parameters...
Incorporating temporal variation in seabird telemetry data: time variant kernel density models
Andrew Gilbert, Evan M. Adams, Carl Anderson, Alicia Berlin, Timothy D. Bowman, Emily Connelly, Scott Gilliland, Carrie E. Gray, Christine Lepage, Dustin Meattey, William Montevecchi, Jason Osenkowski, Lucas Savoy, Iain Stenhouse, Kathryn Williams
2015, Report
A key component of the Mid-Atlantic Baseline Studies project was tracking the individual movements of focal marine bird species (Red-throated Loon [Gavia stellata], Northern Gannet [Morus bassanus], and Surf Scoter [Melanitta perspicillata]) through the use of satellite telemetry. This element of the project was a collaborative effort with the Department...
Net ecosystem production and organic carbon balance of U.S. East Coast estuaries: A synthesis approach
Maria Herrmann, Raymond G. Najjar, W. Michael Kemp, Richard B. Alexander, Elizabeth W. Boyer, Wei-Jun Cai, Peter C. Griffith, Kevin D. Kroeger, S. Leigh McCallister, Richard A. Smith
2015, Global Biogeochemical Cycles (29) 96-111
Net ecosystem production (NEP) and the overall organic carbon budget for the estuaries along the East Coast of the United States are estimated. We focus on the open estuarine waters, excluding the fringing wetlands. We developed empirical models relating NEP to loading ratios of dissolved inorganic nitrogen to total organic...
Combined effects of climate, predation, and density dependence on Greater and Lesser Scaup population dynamics
Beth E. Ross, Mevin Hooten, Jean-Michel DeVink, David N. Koons
2015, Ecological Applications (25) 1606-1617
An understanding of species relationships is critical in the management and conservation of populations facing climate change, yet few studies address how climate alters species interactions and other population drivers. We use a long-term, broad-scale data set of relative abundance to examine the influence of climate, predators, and density dependence...
Analyzing high resolution topography for advancing the understanding of mass and energy transfer through landscapes: A review
Paola Passaiacquaa, Patrick Belmont, Dennis M. Staley, Jeffery Simley, J. Ramon Arrowsmith, Collin A. Bode, Christopher Crosby, Stephen DeLong, Nancy Glenn, Sara Kelly, Dimitri Lague, Harish Sangireddy, Keelin Schaffrath, David Tarboton, Thad Wasklewicz, Joseph Wheaton
2015, Earth-Science Reviews (148) 174-193
The study of mass and energy transfer across landscapes has recently evolved to comprehensive considerations acknowledging the role of biota and humans as geomorphic agents, as well as the importance of small-scale landscape features. A contributing and supporting factor to this evolution is the emergence over the last two...
Characterization of stormwater runoff from bridges in North Carolina and the effects of bridge runoff on receiving streams
Chad Wagner, Sharon Fitzgerald, Matthew Lauffer
2015, Conference Paper, Proceedings of the 2015 International Conference on Ecology & Transportation
The presentation will provide an overview of a collaborative study between USGS, NC Department of Transportation and URS Corporation to characterize stormwater runoff from bridges in North Carolina and the effects of bridge runoff on receiving streams. This investigation measured bridge deck runoff from 15 bridges for 12-15 storms, stream...
Elk habitat suitability map for North Carolina
Steven G. Williams, David T. Cobb, Jaime A. Collazo
2015, Journal of the Southeastern Association of Fish and Wildlife Agencies (2) 181-186
Although eastern elk (Cervus elaphus canadensis) were extirpated from the eastern United States in the 19th century, they were successfully reintroduced in the North Carolina portion of the Great Smoky Mountains National Park in the early 2000s. The North Carolina Wildlife Resources Commission (NCWRC) is evaluating the prospect of reintroducing...
Synthesis of current knowledge on post-fire seeding for soil stabilization and invasive species control
Jan L. Beyers, David A. Pyke, Troy Wirth
2015, Report
The General Accounting Office has identified a need for better information on the effectiveness of post-fire emergency stabilization and rehabilitation methods used by the U.S. Forest Service and Department of Interior (DOI) agencies. Since reviews were published on treatment effectiveness in the early 2000s, treatment choices have changed and increased...
High-speed limnology: Using advanced sensors to investigate spatial variability in biogeochemistry and hydrology
John T. Crawford, Luke C. Loken, Nora J. Casson, Colin Smith, Amanda G. Stone, Luke A. Winslow
2015, Environmental Science & Technology (49) 442-450
Advanced sensor technology is widely used in aquatic monitoring and research. Most applications focus on temporal variability, whereas spatial variability has been challenging to document. We assess the capability of water chemistry sensors embedded in a high-speed water intake system to document spatial variability. This new sensor platform continuously samples...
Evaluation of stream flow effects on smolt survival in the Yakima River Basin, Washington, 2012-2014
Ian Courter, Tommy Garrison, Tobias J. Kock, Russell W. Perry
2015, Report
The influence of stream flow on survival of emigrating juvenile (smolts) Pacific salmon Oncorhynchus spp. and steelhead trout O. mykiss is of key management interest. However, few studies have quantified flow effects on smolt migration survival, and available information does not indicate a consistent flow-survival relationship within the typical range...
Survival and recovery rates of mottled ducks banded in Texas and Louisiana
David A. Haukos
2015, Journal of the Southeastern Association of Fish and Wildlife Agencies (2) 214-220
The Western Gulf Coast population of the mottled duck (Anas fulvigula) is dependent on the Gulf coastal marsh to complete its entire life cycle. Band recovery data can be used to monitor mottled duck populations by estimating annual survival, indexing harvest rate, and assessing movements. Band returns from hunting seasons...
On-line hydrogen-isotope measurements of organic samples using elemental chromium: An extension for high temperature elemental-analyzer techniques
Matthias Gehre, Julian Renpenning, Tetyana Gilevska, Haiping Qi, Tyler B. Coplen, Harro A.J. Meijer, Willi A. Brand, Arndt Schimmelmann
2015, Analytical Chemistry (87) 5198-5205
The high temperature conversion (HTC) technique using an elemental analyzer with a glassy carbon tube and filling (temperature conversion/elemental analysis, TC/EA) is a widely used method for hydrogen isotopic analysis of water and many solid and liquid organic samples with analysis by isotope-ratio mass spectrometry (IRMS). However, the TC/EA IRMS...
Accounting for imperfect detection in Hill numbers for biodiversity studies
Kristin M. Broms, Mevin Hooten, Ryan M. Fitzpatrick
2015, Methods in Ecology and Evolution (6) 99-108
Hill numbers unify biodiversity metrics by combining several into one expression. For example, species richness, Shannon's diversity index and the Gini–Simpson index are a few of the most used diversity measures, and they can be expressed as Hill numbers. Traditionally, Hill numbers have been calculated from relative...
Estimating sturgeon abundance in the Carolinas using side-scan sonar
H. Jared Flowers, Joseph E. Hightower
2015, Marine and Coastal Fisheries: Dynamics, Management, and Ecosystem Science (7) 1-9
Sturgeons (Acipenseridae) are one of the most threatened taxa worldwide, including species in North Carolina and South Carolina. Populations of Atlantic Sturgeon Acipenser oxyrinchus in the Carolinas have been significantly reduced from historical levels by a combination of intense fishing and habitat loss. There is a need for estimates of...
Climate change and vulnerability of bull trout (Salvelinus confluentus) in a fire-prone landscape.
Jeffrey A. Falke, Rebecca L. Flitcroft, Jason B. Dunham, Kristina M. McNyset, Paul F. Hessburg, Gordon H. Reeves
2015, Canadian Journal of Fisheries and Aquatic Sciences (72) 304-318
Linked atmospheric and wildfire changes will complicate future management of native coldwater fishes in fire-prone landscapes, and new approaches to management that incorporate uncertainty are needed to address this challenge. We used a Bayesian network (BN) approach to evaluate population vulnerability of...
Day-roost tree selection by northern long-eared bats - What do non-roost tree comparisons and one year of data really tell us?
Alexander Silvis, W. Mark Ford, Eric R. Britzke
2015, Global Ecology and Conservation (3) 756-763
Bat day-roost selection often is described through comparisons of day-roosts with randomly selected, and assumed unused, trees. Relatively few studies, however, look at patterns of multi-year selection or compare day-roosts used across years. We explored day-roost selection using 2 years of roost selection data for female northern long-eared bats (Myotis...
Contrasting fish assemblages in free-flowing and impounded tributaries to the Upper Delaware River: Implications for conserving biodiversity
Barry P. Baldigo, Mari-Beth Delucia, Walter D. Keller, George E. Schuler, Colin D. Apse, Tara Moberg
2015, Book chapter, Advances in Environmental Research
The Neversink River and the Beaver Kill in southeastern New York are major tributaries to the Delaware River, the longest undammed river east of the Mississippi. While the Beaver Kill is free flowing for its entire length, the Neversink River is subdivided by the Neversink Reservoir, which likely affects the...
Using the Maxent program for species distribution modelling to assess invasion risk
Catherine S. Jarnevich, Nicholas E. Young
R.C Venette, editor(s)
2015, Book chapter, Pest Risk Modelling and Mapping for Invasive Alien Species
MAXENT is a software package used to relate known species occurrences to information describing the environment, such as climate, topography, anthropogenic features or soil data, and forecast the presence or absence of a species at unsampled locations. This particular method is one of the most popular species distribution modelling techniques...
Sea lamprey mark type, wounding rate, and parasite-host preference and abundance relationships for lake trout and other species in Lake Ontario
Brian F. Lantry, Jean Adams, Gavin Christie, Teodore Schaner, James Bowlby, Michael Keir, Jana Lantry, Paul Sullivan, Daniel Bishop, Ted Treska, Bruce Morrison
2015, Report
We examined how the frequency of attacks by Sea Lamprey on fishes in Lake Ontario varied in response to Sea Lamprey abundance and preferred host abundance (Lake Trout >432mm). For this analysis we assembled seven data sets. Two fishery independent surveys for Lake Trout: US Geological Survey (USGS)/New York State...
Discrete-storm water-table fluctuation method to estimate episodic recharge.
John R. Nimmo, Charles Horowittz, Lara Mitchell
2015, Groundwater (53) 282-292
We have developed a method to identify and quantify recharge episodes, along with their associated infiltration-related inputs, by a consistent, systematic procedure. Our algorithm partitions a time series of water levels into discrete recharge episodes and intervals of no episodic recharge. It correlates each recharge episode with a specific interval...
An updated conceptual model of Delta Smelt biology: Our evolving understanding of an estuarine fish
Randy Baxter, Larry R. Brown, Gonzalo Castillo, Louise Conrad, Steven D. Culberson, Matthew P. Dekar, Melissa Dekar, Frederick Feyrer, Thaddeus Hunt, Kristopher Jones, Joseph Kirsch, Anke Mueller-Solger, Matthew Nobriga, Steven B. Slater, Ted Sommer, Kelly Souza, Gregg Erickson, Stephanie Fong, Karen Gehrts, Lenny Grimaldo, Bruce Herbold
2015, Technical Report 90
The main purpose of this report is to provide an up-to-date assessment and conceptual model of factors affecting Delta Smelt (Hypomesus transpacificus) throughout its primarily annual life cycle and to demonstrate how this conceptual model can be used for scientific and management purposes. The Delta Smelt is a small estuarine...
Automated lidar-derived canopy height estimates for the Upper Mississippi River System
Enrika Hlavacek
2015, Thesis
Land cover/land use (LCU) classifications serve as important decision support products for researchers and land managers. The LCU classifications produced by the U.S. Geological Survey’s Upper Midwest Environmental Sciences Center (UMESC) include canopy height estimates that are assigned through manual aerial photography interpretation techniques. In an effort to improve upon...
Validation of the SCEC broadband platform V14.3 simulation methods using pseudo spectral acceleration data
Douglas S. Dreger, Gregory C. Beroza, Steven M. Day, Christine A. Goulet, Thomas H Jordan, Paul A. Spudich, Jonathan P. Stewart
2015, Seismological Research Letters (86) 39-47
This paper summarizes the evaluation of ground motion simulation methods implemented on the SCEC Broadband Platform (BBP), version 14.3 (as of March 2014). A seven-member panel, the authorship of this article, was formed to evaluate those methods for the prediction of pseudo-­‐spectral accelerations (PSAs) of ground motion. The panel’s mandate...