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The USGS provides unbiased, objective, and impartial scientific information upon which our audiences, including resource managers, planners, and other entities, rely.
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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Landscape and connectivity metrics as a spatial tool to support invasive annual grass management decisions Landscape and connectivity metrics as a spatial tool to support invasive annual grass management decisions
The spatial patterns and context of invasions are increasingly recognized as important for successful and efficient management actions. Beyond mapping occurrence or percent cover in pixels, spatial summary information that describes the size and arrangement of patches in the context of a larger landscape (e.g., infested regions, connected patch networks) can add a depth of information...
Authors
Erin K. Buchholtz, Julie A. Heinrichs, Michele R. Crist
Revising supraglacial rock avalanche magnitudes and frequencies in Glacier Bay National Park, Alaska Revising supraglacial rock avalanche magnitudes and frequencies in Glacier Bay National Park, Alaska
The frequency of large supraglacial landslides (rock avalanches) occurring in glacial environments is thought to be increasing due to feedbacks with climate warming and permafrost degradation. However, it is difficult to (i) test this; (ii) establish cause–effect relationships; and (iii) determine associated lag-times, due to both temporal and spatial biases in detection rates. Here we...
Authors
William Smith, Stuart A. Dunning, Neil Ross, Jon Telling, Erin K. Bessette-Kirton, Dan H. Shugar, Jeffrey A. Coe, M. Geertsema
Fecal DNA metabarcoding shows credible short-term prey detections and explains variation in the gut microbiome of two polar bear subpopulations Fecal DNA metabarcoding shows credible short-term prey detections and explains variation in the gut microbiome of two polar bear subpopulations
This study developed and evaluated DNA metabarcoding to identify the presence of pinniped and cetacean prey DNA in fecal samples of East Greenland (EG) and Southern Beaufort Sea (SB) polar bears Ursus maritimus sampled in the spring of 2015-2019. Prey DNA was detected in half (49/92) of all samples, and when detected, ringed seal Pusa hispida was the predominant prey species, identified...
Authors
Megan Franz, L Whyte, Todd C. Atwood, Damian M. Menning, Sarah A. Sonsthagen, Sandra Talbot, Kristin L. Laidre, Emmanuel Gonzalez, Melissa McKinney
Using corrected and imputed polarity measurements to improve focal mechanisms in a regional earthquake catalog near the Mt. Lewis Fault Zone, California Using corrected and imputed polarity measurements to improve focal mechanisms in a regional earthquake catalog near the Mt. Lewis Fault Zone, California
We utilized relative polarity measurements and machine learning techniques to better resolve focal mechanisms and stress orientations considering a catalog of ∼29,000 relocated earthquakes that occurred during 1984–2021 in the southeastern San Francisco Bay Area. Earthquake focal mechanisms are commonly produced using P wave first motion polarities, which traditionally requires events to...
Authors
Robert Skoumal, Jeanne L. Hardebeck, David R. Shelly
Landscape configuration influences Oma‘o (Myadestes obscurus) song diversity Landscape configuration influences Oma‘o (Myadestes obscurus) song diversity
Acoustic communication in the form of songs is a learned behavior in oscine that can be passed down from one generation to the next through cultural transmission. Over time songs can change when populations become isolated from one another, creating dialects that are distinct to a population. Habitat fragmentation is an isolating mechanism that can influence differences in songs between
Authors
Nicole Fernandez, Kristina L. Paxton, Eben H. Paxton, Adam A. Pack, Patrick J. Hart
Genetic diversity, structure, and effective population size of an endangered, endemic hoary bat, ʻōpeʻapeʻa, across the Hawaiian Islands Genetic diversity, structure, and effective population size of an endangered, endemic hoary bat, ʻōpeʻapeʻa, across the Hawaiian Islands
Island bat species are disproportionately at risk of extinction, and Hawaiʻi’s only native terrestrial land mammal, the Hawaiian hoary bat (Lasiurus semotus) locally known as ʻōpeʻapeʻa, is no exception. To effectively manage this bat species with an archipelago-wide distribution, it is important to determine the population size on each island and connectivity between islands. We used 18...
Authors
Corinna Pinzari, Mona Renee Bellinger, Donald K. Price, Frank J Bonaccorso
Context-dependent representation of within- and between-model uncertainty: Aggregating probabilistic predictions in infectious disease epidemiology Context-dependent representation of within- and between-model uncertainty: Aggregating probabilistic predictions in infectious disease epidemiology
Probabilistic predictions support public health planning and decision making, especially in infectious disease emergencies. Aggregating outputs from multiple models yields more robust predictions of outcomes and associated uncertainty. While the selection of an aggregation method can be guided by retrospective performance evaluations, this is not always possible. For example, if...
Authors
Emily Howerton, Michael C. Runge, Tiffany L. Bogich, Rebecca K. Borchering, Hidetoshi Inamine, Justin Lessler, Luke C Mullany, William J.M. Probert, Claire P. Smith, Shaun Truelove, Cècile Viboud, Katriona Shea
Improvements to estimate ADCP uncertainty sources for discharge measurements Improvements to estimate ADCP uncertainty sources for discharge measurements
The use of moving boat ADCPs (Acoustic Doppler Current Profilers) for discharge measurements requires identification of the sources and magnitude of uncertainty to ensure accurate measurements. Recently, a tool known as QUant was developed to estimate the contribution to the uncertainty estimates for each transect of moving-boat ADCP discharge measurements, by varying different sampling
Authors
Jose M. Diaz Lozada, Carlos M. Garcia, Kevin Oberg, Thomas M. Over, Federico Flores Nieto
Diet composition and resource overlap of sympatric native and introduced salmonids across neighboring streams during a peak discharge event Diet composition and resource overlap of sympatric native and introduced salmonids across neighboring streams during a peak discharge event
Species assemblages composed of non-native and native fishes are found in freshwater systems throughout the world, and interactions such as interspecific competition that may negatively affect native species are expected when non-native species are present. In the Smith River watershed, Montana, rainbow trout were introduced by 1930. Native mountain whitefish and non-native rainbow trout...
Authors
Tanner L. Cox, Michael J. Lance, Lindsey K. Albertson, Michelle A. Briggs, Adeline J. Dutton, Alexander V. Zale
Over half a century record of limnology data from Lake Powell, desert southwest United States: From reservoir filling to present day (1964–2021) Over half a century record of limnology data from Lake Powell, desert southwest United States: From reservoir filling to present day (1964–2021)
Lake Powell is a large water storage reservoir in the arid southwestern United States. Here, we present a 58-yr limnology dataset that captures water quality parameters from reservoir filling to present day (temperature, salinity, major ions, total suspended solids), as well as a 38-yr record of Secchi depth, and a ~ 30-yr record of nutrients, phytoplankton, and zooplankton assemblages...
Authors
Bridget R. Deemer, Caitlin M. Andrews, Kristin E. Strock, Nicholas Voichick, James Hensleigh, John Beaver, Robert Radtke
A novel non-destructive workflow for examining germanium and co-substituents in ZnS A novel non-destructive workflow for examining germanium and co-substituents in ZnS
A suite of complementary techniques was used to examine germanium (Ge), a byproduct critical element, and co-substituent trace elements in ZnS and mine wastes from four mineral districts where germanium is, or has been, produced within the United States. This contribution establishes a comprehensive workflow for characterizing Ge and other trace elements, which captures the full...
Authors
Sarah M. Hayes, Ryan J. McAleer, Nadine M. Piatak, Sarah Jane White, Robert R. Seal,
Stochastic watershed model ensembles for long-range planning: Verification and validation Stochastic watershed model ensembles for long-range planning: Verification and validation
Deterministic watershed models (DWMs) are used in nearly all hydrologic planning, design, and management activities, yet they cannot generate streamflow ensembles needed for hydrologic risk management (HRM). The stochastic component of DWMs is often ignored in practice, leading to a systematic bias in extreme events. Since traditional stochastic streamflow models used in HRM struggle to...
Authors
Ghazal Shabestanipour, Zachary P Brodeur, William H. Farmer, Scott Steinschneider, Richard M Vogel, Jonathan Lamontagne