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Browse more than 65,000 articles authored by our scientists over the past 100+ year history of the USGS and refine search by topic, location, year, and advanced search.
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Formation and evolution of the Pacific-North American (San Andreas) plate boundary: Constraints from the crustal architecture of northern California Formation and evolution of the Pacific-North American (San Andreas) plate boundary: Constraints from the crustal architecture of northern California
The northward migration of the Mendocino triple junction (MTJ) drives a fundamental plate boundary transformation from convergence to translation; producing a series of strike-slip faults, that become the San Andreas plate boundary. We find that the 3-D structure of the Pacific plate lithosphere in the vicinity of the MTJ controls the location of San Andreas plate boundary formation. At...
Authors
Kevin P. Furlong, Antonio Villasenor, Harley M. Benz, Kirsty A. McKenzie
Effects of telemetry collars on two free-roaming feral equid species Effects of telemetry collars on two free-roaming feral equid species
There are two species of free-roaming feral equids in North America: horses (Equus caballus) and donkeys or “burros” (E. asinus). Both species were introduced as domestic animals to North America in the early 1500s and currently inhabit rangelands across the western United States, Canada, and all continents except Antarctica. Despite their global distribution, little is known about their...
Authors
Kathryn A. Schoenecker, Sarah King, Jacob D. Hennig, Mary C. Cole, J. Derek Scasta, Jeffrey L. Beck
Human activities shape global patterns of decomposition rates in rivers Human activities shape global patterns of decomposition rates in rivers
Rivers and streams contribute to global carbon cycling by decomposing immense quantities of terrestrial plant matter. However, decomposition rates are highly variable and large-scale patterns and drivers of this process remain poorly understood. Using a cellulose-based assay to reflect the primary constituent of plant detritus, we generated a predictive model (81% variance explained) for...
Authors
Scott Tiegs, Krista A. Capps, David M. Costello, John Paul Schmidt, Christopher J. Patrick, Jennifer Follstad Shah, Carri J. LeRoy, Vicenc Acuna, Ricardo Albarino, Daniel C. Allen, Cecilia Alonso, Patricio Andino, Clay Arango, Jukka Aroviita, Marcus Barbosa, Leon A. Barmuta, Colden V. Baxter, Brent Bellinger, Luz Boyero, Lyubov Bragina, Lee E. Brown, Andreas Bruder, Denise Bruesewitz, Francis Burdon, Marcos Callisto, Antonio G. Camacho, Cristina Canhoto, Maria Castillo, Eric Chauvet, Joanne Clapcott, Fanny Colas, Checo Colon-Gaud, Julien Cornut, Veronica Crespo-Perez, Wyatt F. Cross, Joseph M. Culp, Michael Danger, Olivier Dangles, Elvira de Eyto, Alison Derry, Veronica Diaz-Villanueva, Michael Douglas, Arturo Elosegi, Andrea Encalada, Sally Entrekin, Rodrigo Espinosa, Veronica Ferreira, Carmen Ferriol, Kyla Flanagan, Alexander Flecker, Tadeusz Fleituch, André Frainer, Nikolai Friberg, Paul C. Frost, Erica A. Garcia, Liliana Garcia-Lago, Pavel Garcia Soto, Mark Gessner, Sudeep Ghate, Darren Giling, Alan Gilmer, Jose Goncalves, Rosario Gonzales, Manuel Graca, Mike Grace, Natalie A. Griffiths, Hans-Peter Grossart, Francois Guerold, Vlad Gulis, Pablo E. Gutiérrez-Fonseca, Luiz Hepp, Scott Higgins, Takuo Hishi, Joseph Huddart, John P. Hudson, Moss Imberger, Carlos Iniguez-Armijos, Mark Isken, Tomoya Iwata, Dave Janetski, Andrea Kirkwood, Aaron A. Koning, Sarian Kosten, Kevin Kuehn, Hjalmar Laudon, Peter Leavitt, Aurea Lemes da Silva, Shawn Leroux, Peter Lisi, Richard Mackenzie, Amy M Marcarelli, Frank Masese, Peter B. McIntyre, Brendan G. McKie, Adriana Medeiros, Kristian Meissner, Marko Milisa, Shailendra Mishra, Yo Miyake, Ashley Moerke, Shorok Mombrikotb, Robert J Mooney, Tim Moulton, Timo Muotka, Junjiro N. Negishi, Vinicius Neres-Lima, Mika Nieminen, Jorge Nimptsch, Jakub Ondruch, Riku Paavola, Isabel Pardo, Edwin Peeters, Jesus Pozo, Aaron Prussian, Estefania Quenta, Brian Reid, John S. Richardson, Anna Rigosi, Jose Rincon, Geta Risnoveanu, Chris Robinson, Lorena Rodriguez-Gallego, Todd V Royer, James A. Rusak, Anna Santamans, Geza Selmeczy, Gelas Simiyu, Agnija Skuja, Jerzy Smykla, Ryan A. Sponseller, Kandikere Sridhar, Aaron Stoler, Christopher M. Swan, Franco Teixeira-de Mello, Jonathan Tonkin, Sari Uusheimo, Allison Veach, Sirje Vilbaste, Lena Vought, Chiao-Ping Wang, Jackson Webster, Paul B. Wilson, Stefan Woelfl, Guy Woodward, Marguerite A. Xenopoulos, Adam Yates, Chihiro Yoshimura, Catherine Yule, Yixin Zhang, Jacob Aaron Zwart
Evaluating satellite-transmitter backpack-harness effects on greater sage-grouse survival and device retention in the Great Basin Evaluating satellite-transmitter backpack-harness effects on greater sage-grouse survival and device retention in the Great Basin
Wildlife tracking studies have become ubiquitous in ecology and now provide previously unobtainable data regarding individual movement, vital rates, and population demographics. However, tracking devices can potentially reduce survival of study subjects, generating biases in the vital rates they seek to measure. Previous studies have found that greater sage-grouse (Centrocercus...
Authors
Carl G. Lundblad, Christopher R. Anthony, Tyler Dungannon, Kimberly A. Haab, Elizabeth M. Schuyler, Chelsea E. Sink, Katie M. Dugger, Christian A. Hagen
Carbon isotope trends across a century of herbarium specimens suggest CO2 fertilization of C4 grasses. Carbon isotope trends across a century of herbarium specimens suggest CO2 fertilization of C4 grasses.
Increasing atmospheric CO2 is changing the dynamics of tropical savanna vegetation. C3 trees and grasses are known to experience CO2 fertilization, whereas responses to CO2 by C4 grasses are more ambiguous.Here, we sample stable carbon isotope trends in herbarium collections of South African C4 and C3 grasses to reconstruct 13C discrimination.We found that C3 grasses showed no trends in...
Authors
Isa del Toro, Madelon Florence Case, Allison Karp, Jasper Slingsby, A. Carla Staver
Why snow is crucial for water supply — And what will happen when it becomes scarce Why snow is crucial for water supply — And what will happen when it becomes scarce
Analysis of 70 years of snowfall in the Northern Hemisphere reveals that snow buffers the effect of varying precipitation levels on streamflow. The link highlights the need to rethink water-resource management as snow levels decline.
Authors
Karen R. Ryberg
Two risk assessments: Evaluating the use of indicator HF183 Bacteroides versus pathogen measurements for modelling recreational illness risks in an urban watershed Two risk assessments: Evaluating the use of indicator HF183 Bacteroides versus pathogen measurements for modelling recreational illness risks in an urban watershed
The purpose of this study was to evaluate the performance of HF183 Bacteroides for estimating pathogen exposures during recreational water activities. We compared the use of Bacteroides-based exposure assessment to exposure assessment that relied on pathogen measurements. We considered two types of recreational water sites: those impacted by combined sewer overflows (CSOs) and those not...
Authors
K Skiendzielewski, Tucker R. Burch, Joel P. Stokdyk, Shannon McGinnis, S McLoughlin, Aaron D. Firnstahl, Sandy Spencer, Mark A. Borchardt, Heather Murphy
Temporally dense monitoring of pathogen occurrence at four drinking-water well sites – Insights and Implications Temporally dense monitoring of pathogen occurrence at four drinking-water well sites – Insights and Implications
Yearlong, event based, microbiological and chemical sampling was conducted at four public water supply well sites spanning a range of geologic settings and well depths to look for correlation between precipitation events and microbial occurrence. Near-continuous monitoring using autosamplers occurred just before, during, and after 5–7 sampling events triggered by rainfall and/or snowmelt
Authors
James F. Walsh, Randall J. Hunt, Anita C. Anderson, David W. Owens, Nancy Rice
A phylogeographical study of the discontinuously distributed Harlequin Duck (Histrionicus histrionicus) A phylogeographical study of the discontinuously distributed Harlequin Duck (Histrionicus histrionicus)
Species distributions are often indicative of historical biogeographical events and contemporary spatial biodiversity patterns. The Harlequin Duck Histrionicus histrionicus is a sea duck of conservation concern that has a disjunct distribution, with discrete portions of its range associated with northern Pacific and Atlantic Ocean basins. Movement data indicate migratory connectivity...
Authors
Kim T Scribner, Sandra Talbot, Barbara J. Pierson, John D Robinson, Richard B. Lanctot, Daniel Esler, Kathryn Dickson
Thermal transfer rate is slower in bigger fish: How does body size affect response time of small, implantable temperature recording tags? Thermal transfer rate is slower in bigger fish: How does body size affect response time of small, implantable temperature recording tags?
The recent miniaturisation of implantable temperature recording tags has made measuring the water temperatures fish experience in the wild possible, but there may be a body size-dependent delay in implanted tag response time to changes in external temperature. To determine whether fish body size affects the response rate of implanted temperature tags, we implanted 20 Salvelinus...
Authors
Matthew J. O'Donnell, Amy M. Regish, Stephen D. McCormick, Benjamin Letcher
Retrospective review of the pathology of American pikas Retrospective review of the pathology of American pikas
American pikas (Ochotona princeps) are small lagomorphs that live in mountainous talus areas of western North America. Studies on the histopathology of American pikas are limited. We summarize here the clinical histories, and gross and histologic findings of 12 American pikas, including 9 captive (wild-caught) and 3 wild animals. Death was often attributed to stress (transport, handling
Authors
Adrienne Barrett, Kali Holder, Susan Knowles, Elise E. B. LaDouceur
Changes in soil erosion caused by wildfire: A conceptual biogeographic model Changes in soil erosion caused by wildfire: A conceptual biogeographic model
Soil erosion rates after wildfire are strongly controlled by intrinsic properties such as topography, weather, climate, soil, and vegetation. These landscape and hydroclimatic properties are important in determining post-fire erosion rates; however, their influence on post-fire erosion and their interaction with the intensity of a wildfire remains uncertain. A key limitation in resolving...
Authors
Philip J. Noske, Petter Nyman, Patrick N.J. Lane, Francis K. Rengers, Gary J. Sheridan