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Publications

Browse more than 160,000 publications authored by our scientists over the past 100+ year history of the USGS.  Publications available are: USGS-authored journal articles, series reports, book chapters, other government publications, and more.

Filter Total Items: 175041

The influence of grazing on the spatiotemporal activity patterns of a primary sage-grouse nest predator The influence of grazing on the spatiotemporal activity patterns of a primary sage-grouse nest predator

Perturbations in ecological processes can occur when wildlife alter their spatiotemporal activity patterns to avoid human activities that they perceive as a risk. Such perturbations can have cascading effects throughout wildlife communities. For greater sage-grouse (Centrocercus urophasianus; hereafter sage-grouse), nest predation plays an important role in population dynamics. Domestic...
Authors
Nolan A. Helmstetter, Courtney J. Conway, Shane Roberts, Paul D. Makela, Lisette P. Waits

Timing and geometry of the Chemehuevi Formation reveal a late Pleistocene sediment pulse into the Lower Colorado River Timing and geometry of the Chemehuevi Formation reveal a late Pleistocene sediment pulse into the Lower Colorado River

The Chemehuevi Formation is a distinctive 50−150-m-thick wedge-shaped Pleistocene sedimentary unit deposited by the Colorado River. It lines the perimeters of the river’s floodplains and bedrock canyons for more than 600 km between the mouth of the Grand Canyon and the delta region in the Gulf of California. The formation is composed of a basal tan to light-yellowish-brown and pale...
Authors
Harrison J. Gray, Kyle House, Adam M. Hudson, Jorge A. Vazquez, Ryan S. Crow, Miriam Primus, Shannon A. Mahan, Tammy M. Rittenour, Keith A. Howard

The projected exposure and response of a natural barrier island system to climate-driven coastal hazards The projected exposure and response of a natural barrier island system to climate-driven coastal hazards

Accelerating sea level rise (SLR) and changing storm patterns will increasingly expose barrier islands to coastal hazards, including flooding, erosion, and rising groundwater tables. We assess the exposure of Cape Lookout National Seashore, a barrier island system in North Carolina (USA), to projected SLR and storm hazards over the twenty-first century. We estimate that with 0.5 m of SLR...
Authors
Jennifer Anne Thomas, Patrick L. Barnard, Sean Vitousek, Li H. Erikson, Kai Alexander Parker, Kees Nederhoff, Kevin M. Befus, Manoochehr Shirzaei

Multi-decadal trophic shifts in Lake Erie yellow perch Perca flavescens Multi-decadal trophic shifts in Lake Erie yellow perch Perca flavescens

In Lake Erie, yellow perch Perca flavescens support vast commercial and recreational fisheries, yet populations have recently declined. Using N = 5889 yellow perch stomachs collected from 1997 to 2021, we explored trends in the feeding ecology and trophic level of yellow perch with generalized additive models. Models revealed a significant decrease in yellow perch trophic level (−0.15...
Authors
Joseph Schmitt, Ann Marie Gorman, Carey Knight, Mark Richard Dufour, James Roberts, Travis Hartman

Predator-specific mortality of sage-grouse nests based on predator DNA on eggshells Predator-specific mortality of sage-grouse nests based on predator DNA on eggshells

Greater sage-grouse (hereafter sage-grouse; Centrocercus urophasianus) populations have declined across their range. Increased nest predation as a result of anthropogenic land use is one mechanism proposed to explain these declines. However, sage-grouse contend with a diverse suite of nest predators that vary in functional traits (e.g., search tactics or hunting mode) and abundance...
Authors
Nolan A. Helmstetter, Courtney J. Conway, Shane Roberts, Jennifer R. Adams, Paul D. Makela, Lisette P. Waits

Tissue distribution and temporal and spatial assessment of per- and polyfluoroalkyl substances (PFAS) in smallmouth bass (Micropterus dolomieu) in the mid-Atlantic United States Tissue distribution and temporal and spatial assessment of per- and polyfluoroalkyl substances (PFAS) in smallmouth bass (Micropterus dolomieu) in the mid-Atlantic United States

Per- and polyfluoroalkyl substances (PFAS) have become an environmental issue worldwide. A first step to assessing potential adverse effects on fish populations is to determine if concentrations of concern are present in a region and if so, in which watersheds. Hence, plasma from adult smallmouth bass Micropterus dolomieu collected at 10 sites within 4 river systems in the mid-Atlantic...
Authors
Vicki S. Blazer, Heather L. Walsh, Cheyenne R. Smith, Stephanie E. Gordon, Brandon J. Keplinger, Timothy Wertz

Cooperative conservation actions improve sage-grouse population performance within the Bi-State Distinct Population Segment Cooperative conservation actions improve sage-grouse population performance within the Bi-State Distinct Population Segment

Developing a robust monitoring framework that integrates efficacy assessments of cooperative conservation and restoration actions in relation to population viability is critical for successful long-term recovery of target ecosystems and species. However, often it is difficult to quantify conservation action efficacy because of the complex, dynamic nature of ecosystem processes and...
Authors
Peter S. Coates, Brian G. Prochazka, Sarah C. Webster, Cali L. Weise, Cameron L. Aldridge, Michael S. O’Donnell, Lief A. Wiechman, Kevin E. Doherty, John C. Tull

Mangrove freeze resistance and resilience across a tropical-temperate transitional zone Mangrove freeze resistance and resilience across a tropical-temperate transitional zone

Freeze events govern the distribution and structure of mangrove ecosystems, especially in tropical-temperate transitional zones. Understanding mangrove responses to freezing is crucial for predicting their poleward expansion under climate change. However, there is a need for field-based measurements of mangrove freeze resistance and resilience.After an extreme winter storm in December...
Authors
Yiyang Kang, David A. Kaplan, Michael Osland

Self-potential tomography preconditioned by particle swarm optimization— Application to monitoring hyporheic exchange in a bedrock river Self-potential tomography preconditioned by particle swarm optimization— Application to monitoring hyporheic exchange in a bedrock river

A self-potential (SP) data-inversion algorithm was developed and tested on an analytical model of electrical-potential profile data attributed to single and multiple polarized electrical sources. The developed algorithm was then validated by an application to SP-monitoring field data measured on the floodplain of East Fork Poplar Creek, Oak Ridge, Tennessee, to image electrical sources...
Authors
Scott Ikard, Kenneth C. Carroll, Scott C. Brooks, Dale F. Rucker, Gladisol Smith-Vega, Aubrey Elwes

Handling effects on dispersal of PIT-tagged Flannelmouth Sucker Handling effects on dispersal of PIT-tagged Flannelmouth Sucker

Objective Handling and tagging migrating fish might alter their behavior, limiting inference from mark–recapture studies. Posthandling flight of tributary spawning Flannelmouth Sucker Catostomus latipinnis was previously identified in Coal Creek in the upper Colorado River basin. Our objective was to determine if similar issues were present at McElmo Creek in the San Juan River basin...
Authors
Sophia Marie Bonjour, Keith B. Gido, Mark C. McKinstry

Imaging of seismic discontinuities using an adjoint method Imaging of seismic discontinuities using an adjoint method

For imaging of seismic discontinuities at depth, reverse time migration (RTM) is a powerful method to apply to recordings of seismic events. It is especially powerful when an extensive receiver array, numerous seismic sources, or both, permit adequate reconstruction of incident and scattered wavefields at depth. Reconstructing either the incident or scattered wavefield at depth becomes...
Authors
Frederick Pollitz, Leah Langer

Radiogenic strontium- and uranium-isotope tracers of water-rock interactions and hydrothermal flow in the Upper Geyser Basin, Yellowstone Plateau Volcanic Field, USA Radiogenic strontium- and uranium-isotope tracers of water-rock interactions and hydrothermal flow in the Upper Geyser Basin, Yellowstone Plateau Volcanic Field, USA

Natural radiogenic isotopes (primarily 87Sr/86Sr) from hot springs in the Upper Geyser Basin of the Yellowstone Plateau volcanic field and associated rocks were used to evaluate groundwater flow patterns, water-rock reactions, and the extent of mixing between various groundwater sources. Thermal waters have very low uranium concentrations and 234U/238U activity ratios near 1.0, which...
Authors
James B. Paces, Shaul Hurwitz, Lauren N Harrison, Jacob B. Lowenstern, R. Blaine McCleskey
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