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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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On the ratio of full‐resonance to square‐root‐impedance amplifications for shear‐wave velocity profiles that are a continuous function of depth On the ratio of full‐resonance to square‐root‐impedance amplifications for shear‐wave velocity profiles that are a continuous function of depth

Amplifications of seismic waves traveling upward through a continuous, interface‐free velocity profile are consistently smaller when computed using the square‐root‐impedance (SRI) method than when computed using full‐resonance (FR) calculations. This was found for a wide range of velocity profiles. For realistic profiles, for which the gradient of velocity decreases with depth, the...
Authors
David Boore, Norm A Abrahamson

Triggering conditions, runout, and downstream impacts of debris flows following the 2021 Flag Fire, Arizona, USA Triggering conditions, runout, and downstream impacts of debris flows following the 2021 Flag Fire, Arizona, USA

Debris flows pose a serious threat to communities in mountainous areas, particularly in the years following wildfire. These events have been widely studied in regions where post-wildfire debris flows have been historically frequent, such as southern California. However, the threat of post-wildfire debris flows is increasing in many regions where detailed data on debris-flow physical...
Authors
Alexander N. Gorr, Luke A. McGuire, Rebecca Beers, Olivia J. Hoch

Global review reveals how disparate study motivations, analytical designs, and focal ions limit understanding of salinization effects on freshwater animals Global review reveals how disparate study motivations, analytical designs, and focal ions limit understanding of salinization effects on freshwater animals

Global salinization of freshwaters is adversely affecting biotic communities and ecosystem processes. We reviewed six decades (1960–2020) of literature published on animal responses to increased salinities across different taxonomic and ecological contexts and identified knowledge gaps. From 585 journal articles, we characterized 5924 responses of mollusks, crustaceans, zooplankton, non...
Authors
Richard H. Walker, Abigail C. Belvin, Joshua B. Mouser, Amanda Pennino, Stephen Plont, Christopher D. Robinson, Lucy B. Smith, Jyoti Thapa, Carl E. Zipper, Paul L. Angermeier, Sally A. Entrekin

Parental infanticide by egg destruction in Red-billed Tropicbirds Phaethon aethereus on the Caribbean island of Sint Eustatius Parental infanticide by egg destruction in Red-billed Tropicbirds Phaethon aethereus on the Caribbean island of Sint Eustatius

Avian reproduction is a process that requires extensive energetic input by parents, particularly in pelagic seabirds. Parental infanticide has rarely been reported in pelagic seabirds, and its frequency among taxa is therefore difficult to determine. Using data from remote cameras, two cases of probable parental infanticide in Red-billed Tropicbirds Phaethon aethereus were captured on...
Authors
Hailley Danielson-Owczynsky, Hannah Madden, Patrick G.R. Jodice

Spatial and individual factors mediate the tissue burden of polycyclic aromatic hydrocarbons in adult and chick brown pelicans in the northern Gulf of Mexico Spatial and individual factors mediate the tissue burden of polycyclic aromatic hydrocarbons in adult and chick brown pelicans in the northern Gulf of Mexico

The northern Gulf of Mexico supports a substantial level of oil and gas extraction in marine waters and experiences acute and chronic exposure to marine pollution events. The region also supports a diverse array of breeding and migratory seabirds that are exposed to these pollutants during foraging and other activities. Among the pollutants of highest concern within the region are...
Authors
Patrick G.R. Jodice, Juliet S. Lamb, Yvan G. Satgé, Christopher Perkins

Impact of dams on stream fish diversity: A different result Impact of dams on stream fish diversity: A different result

Impoundments can drastically change the physical and biological characteristics of fluvial systems. Changes in the physical characteristics, such as reductions in flow, increased sediment deposition, and increased surface area, often influence the system’s biological components, including plant, macroinvertebrate, and fish assemblages. In addition to having direct effects on impounded...
Authors
Nicky M. Faucheux, Leandro E. Miranda, Jason M. Taylor, Jerry L. Farris

Pilot study for invasive brown treesnake baiting in residential areas Pilot study for invasive brown treesnake baiting in residential areas

The nocturnal brown treesnake (Boiga irregularis; BTS) was accidentally introduced to the island of Guam, USA, in the Western Pacific in 1945. The BTS has spread throughout all terrestrial habitats, causing wildlife loss and economic damage. Several tools and techniques have been developed to locally reduce BTS numbers and prevent their spread to other islands. The common analgesic...
Authors
Shane S Siers, Juan-Carlos Mungaray, Jordan I Barcinas, Jeried E Calaor, Rachel M. Volsteadt, Martin Kastner, Scott Michael Goetz, Melia G. Nafus, Thomas C Hall

Coastal acidification trends and controls in a subtropical estuary, Tampa Bay, Florida USA Coastal acidification trends and controls in a subtropical estuary, Tampa Bay, Florida USA

Many coastal estuaries have experienced declines in pH over the past few decades due to coastal acidification. However, mean monthly water column pH values (collected during daylight hours) have increased in Tampa Bay, Florida over recent decades concurrent with seagrass recovery. We measured changes in carbonate system and water quality variables in Tampa Bay and the near-coastal Gulf...
Authors
Kimberly K. Yates, Christopher Moore, Mitchell K Lemon, Ryan P. Moyer, David A. Tomasko, R. Masserini, Edward T. Sherwood

Toxicological effects assessment for wildlife in the 21st Century: Review of current methods and recommendations for a path forward Toxicological effects assessment for wildlife in the 21st Century: Review of current methods and recommendations for a path forward

Model species (e.g., granivorous gamebirds, waterfowl, passerines, domesticated rodents) have been used for decades in guideline laboratory tests to generate survival, growth and reproductive data for prospective Ecological Risk Assessments (ERAs) for birds and mammals, while officially adopted risk assessment schemes for amphibians and reptiles do not exist. There are recognized...
Authors
Thomas G. Bean, Val R. Beasley, Philippe Berny, Karen M. Eisenreich, John E. Elliott, Margaret L. Eng, Phyllis C. Fuchsman, Mark S. Johnson, Mason D. King, Rafael Mateo Soria, Connor J. Meyer, Christopher J. Salice, Barnett A. Rattner

Impacts and uncertainties of climate-induced changes in watershed inputs on estuarine hypoxia Impacts and uncertainties of climate-induced changes in watershed inputs on estuarine hypoxia

Multiple climate-driven stressors, including warming and increased nutrient delivery, are exacerbating hypoxia in coastal marine environments. Within coastal watersheds, environmental managers are particularly interested in climate impacts on terrestrial processes, which may undermine the efficacy of management actions designed to reduce eutrophication and consequent low-oxygen...
Authors
Kyle E. Hinson, Marjorie A. M. Friedrichs, Raymond G. Najjar, Maria Herrmann, Zihao Bian, Gopal Bhatt, Pierre St-Laurent, Hanqin Tian, Gary W. Shenk

Abiotic and biotic factors reduce the viability of a high-elevation salamander in its native range Abiotic and biotic factors reduce the viability of a high-elevation salamander in its native range

Amphibian populations are undergoing worldwide declines, and high-elevation, range-restricted amphibian species may be particularly vulnerable to environmental stressors. In particular, future climate change may have disproportional impacts to these ecosystems. Evaluating the combined effects of abiotic changes and biotic interactions simultaneously is important for forecasting the range...
Authors
Evan H. Campbell Grant, Graziella Vittoria DiRenzo, Adrianne Brand

Growth, drought response, and climate-associated genomic structure in whitebark pine in the Sierra Nevada of California Growth, drought response, and climate-associated genomic structure in whitebark pine in the Sierra Nevada of California

Whitebark pine (Pinus albicaulis Engelm.) has experienced rapid population declines and is listed as threatened under the Endangered Species Act in the United States. Whitebark pine in the Sierra Nevada of California represents the southernmost end of the species' distribution and, like other portions of its range, faces threats from an introduced pathogen, native bark beetles, and a...
Authors
Phillip J. van Mantgem, Elizabeth R. Milano, Joan Dudney, Jonathan Nesmith, Amy G. Vandergast, Harold S.J. Zald
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