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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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Recovering individual-level spatial inference from aggregated binary data Recovering individual-level spatial inference from aggregated binary data
Binary regression models are commonly used in disciplines such as epidemiology and ecology to determine how spatial covariates influence individuals. In many studies, binary data are shared in a spatially aggregated form to protect privacy. For example, rather than reporting the location and result for each individual that was tested for a disease, researchers may report that a disease...
Authors
Nelson Walker, Trevor J. Hefley, Anne Ballmann, Robin E. Russell, Daniel P. Walsh
Oxygen isotopes in terrestrial gastropod shells track Quaternary climate change in the American Southwest Oxygen isotopes in terrestrial gastropod shells track Quaternary climate change in the American Southwest
Recent studies have shown the oxygen isotopic composition (δ18O) of modern terrestrial gastropod shells is determined largely by the δ18O of precipitation. This implies that fossil shells could be used to reconstruct the δ18O of paleo-precipitation as long as the isotopic system, including the hydrologic pathways of the local watershed and the gastropod systematics, is well understood...
Authors
Jason A. Rech, Jeffrey S. Pigati, Kathleen B. Springer, Stephanie Bosch, Jeffrey C. Nekola, Yurena Yanes
Moose habitat selection and fitness consequences during two critical winter tick life stages in Vermont, United States Moose habitat selection and fitness consequences during two critical winter tick life stages in Vermont, United States
The moose (Alces alces) is a charismatic species in decline across much of their southern distribution in North America. In the northeastern United States, much of the reduction has been attributed to winter tick (Dermacentor albipictus) infestations. Winter ticks are fairly immobile throughout all life stages, and therefore their distribution patterns at any given time are shaped...
Authors
Joshua Blouin, Jacob Debow, Elias Rosenblatt, James E. Hines, Cedric Alexander, Katherina Gieder, Nicholas Fortin, James Murdoch, Therese M. Donovan
A U.S.-China EcoPartnership study of disturbed wetland vegetation in West Dongting Lake, China A U.S.-China EcoPartnership study of disturbed wetland vegetation in West Dongting Lake, China
West Dongting Lake in China is important for human livelihoods and habitat of migratory waterfowl and other wildlife. The waterway re-engineering and agriculture intensification have contributed to changes in hydrology, sediment, and vegetation on the floodplain. This paper describes an EcoPartnership program conducted by the U.S. Geological Survey, Wetland and Aquatic Research Center...
Authors
Ting Lei, Beth Middleton
Spring phenology drives range shifts in a migratory Arctic ungulate with key implications for the future Spring phenology drives range shifts in a migratory Arctic ungulate with key implications for the future
Annual variation in phenology can have profound effects on the behavior of animals. As climate change advances spring phenology in ecosystems around the globe, it is becoming increasingly important to understand how animals respond to variation in the timing of seasonal events and how their responses may shift in the future. We investigated the influence of spring phenology on the...
Authors
John P. Severson, Heather E. Johnson, Stephen M. Arthur, William Leacock, Michael J. Suitor
Repeating earthquakes during multiple phases of unrest and eruption at Mount Agung, Bali, Indonesia, 2017 Repeating earthquakes during multiple phases of unrest and eruption at Mount Agung, Bali, Indonesia, 2017
In 2017, Mount Agung produced a small (VEI 2) eruption that was preceded by an energetic volcano-tectonic (VT) swarm (>800 earthquakes per day up to M4.9) and two months of declining activity. The period of decreased seismic activity complicated forecasting efforts for scientists monitoring the volcano. We examine the time history of earthquake families at Mount Agung in search of...
Authors
John Wellik, Stephanie G. Prejean, Devy K. Syahbana
Calcium concentrations in the lower Columbia River, USA, are generally sufficient to support invasive bivalve spread Calcium concentrations in the lower Columbia River, USA, are generally sufficient to support invasive bivalve spread
Dissolved calcium concentration [Ca2+] is thought to be a major factor limiting the establishment and thus the spread of invasive bivalves such as zebra (Dreissena polymorpha) and quagga (Dreissena bugensis) mussels. We measured [Ca2+] in 168 water samples collected along ~100 river-km of the lower Columbia River, USA, between June 2018 and March 2020. We found [Ca2+] to range from 13 to...
Authors
Stephen M. Bollens, John A. Harrison, Marc G. Kramer, Gretchen Rollwagen-Bollens, Timothy D. Counihan, Salvador B. Robb-Chavez, Sean T. Nolan
The effect of group size on reproduction in cooperatively breeding gray wolves depends on density The effect of group size on reproduction in cooperatively breeding gray wolves depends on density
In cooperatively breeding species, large group size is often positively related to reproductive success and group persistence. We have a poor understanding, however, of how group sizes within a population affect reproduction particularly as density varies. We hypothesized that at low densities, wolves in both small and large groups would have similar reproductive rates. At high densities...
Authors
D.E. Ausband, Michael S. Mitchell
Broad-scale surface and atmospheric conditions during large fires in south-central Chile Broad-scale surface and atmospheric conditions during large fires in south-central Chile
The unprecedented size of the 2017 wildfires that burned nearly 600,000 hectares of central Chile highlight a need to better understand the climatic conditions under which large fires develop. Here we evaluate synoptic atmospheric conditions at the surface and free troposphere associated with anomalously high (active) versus low (inactive) months of area burned in south-central Chile (ca...
Authors
David B. McWethy, Rene Garreaud, Andres Holz, Gregory T. Pederson
Surface water with more natural temperatures promotes physiological and endocrine changes in landlocked Atlantic salmon smolts Surface water with more natural temperatures promotes physiological and endocrine changes in landlocked Atlantic salmon smolts
Hatchery salmonid smolts are often reared using groundwater with elevated temperatures to maximize growth. Previous work has shown that rearing hatchery smolts in surface water with a more natural thermal regime resulted in increased return rates of adult landlocked Atlantic salmon (Salmo salar). We evaluated whether landlocked Atlantic salmon reared in surface water with a natural...
Authors
Amy M. Regish, William R. Ardren, Nicholas R Staats, Henry Bouchard, Jonah L. Withers, Theodore R. Castro-Santos, Stephen D. McCormick
Modeling of future COVID-19 cases, hospitalizations, and deaths, by vaccination rates and nonpharmaceutical intervention scenarios — United States, April–September 2021 Modeling of future COVID-19 cases, hospitalizations, and deaths, by vaccination rates and nonpharmaceutical intervention scenarios — United States, April–September 2021
What is already known about this topic? Increases in COVID-19 cases in March and early April occurred despite a large-scale vaccination program. Increases coincided with the spread of SARS-CoV-2 variants and relaxation of nonpharmaceutical interventions (NPIs). What is added by this report? Data from six models indicate that with high vaccination coverage and moderate NPI adherence...
Authors
Rebecca K. Borchering, Cecile Viboud, Emily Howerton, Claire P. Smith, Shaun Truelove, Michael C. Runge, Nicholas G. Reich, Lucie Contamin, John Levander, Jessica Salerno, Wilbert van Panhuis, Matt Kinsey, Kate Tallaksen, R. Freddy Obrecht, Laura Asher, Cash Costello, Michael Kelbaugh, Shelby Wilson, Lauren Shin, Molly Gallagher, Luke Mullany, Kaitlin Rainwater-Lovett, Joseph Lemaitre, Juan Dent, Kyra Grantz, Joshua Kaminsky, Stephen Lauer, Elizabeth Lee, Hannah Meredith, Javier Perez-Saez, Lindsay T. Keegan, Dean Karlen, Matteo Chinazzi, Jessica Davis, Kunpeng Mu, Xinyue Xiong, Ana Pastore y Piontti, Alessandro Vespignani, Ajitesh Srivastava, Przemyslaw Porebski, Srinivasan Venkatramanan, Aniruddha Adiga, Bryan Lewis, Brian Klahn, Joseph Outten, James Schlitt, Patrick Corbett, Pyrros A. Telionis, Lijing Wang, Akhil S. Peddireddy, Benjamin Hurt, Jiangzhuo Chen, Anil Vullikanti, Madhav Marathe, Jessica Healy, Rachel B. Slayton, Matthew Biggerstaff, Michael A Johansson, Katriona Shea, Justin Lessler
Effects of elk and bison herbivory on narrowleaf cottonwood Effects of elk and bison herbivory on narrowleaf cottonwood
Ungulate browsing influences the structure and composition of woody plant communities, including species composition and biomass production as well as age distribution, recruitment, and mortality. We evaluated effects of elk and bison herbivory on narrowleaf cottonwood (Populus angustifolia) communities in a semiarid ecosystem in southern Colorado. Cottonwoods in this ecosystem have been...
Authors
Linda C. Zeigenfuss, Kathryn A. Schoenecker