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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: 171237

Point count offsets for estimating population sizes of north American landbirds

Bird monitoring in North America over several decades has generated many open databases, housing millions of structured and semi-structured bird observations. These provide the opportunity to estimate bird densities and population sizes, once variation in factors such as underlying field methods, timing, land cover, proximity to roads, and uneven spatial coverage are accounted for. To facilitate i
Authors
B.P.M. Edwards, A.C. Smith, T.D.S. Docherety, M.A. Gahbauer, C.R. Gillespie, A.R. Grinde, T. Harmer, D. Iles, Steven M. Matsuoka, N.L. Michel, N.L. Murray, G. Niemi, J. Pasher, D. Pavlacky, B. Robinson, B. Ryder, P. Solymos, D. Stralberg, E.J. Zlonis

Divergent Serpentoviruses in free-ranging invasive pythons and native colubrids in southern Florida, United States

Burmese python (Python bivittatus) is an invasive snake that has significantly affected ecosystems in southern Florida, United States. Aside from direct predation and competition, invasive species can also introduce nonnative pathogens that can adversely affect native species. The subfamily Serpentovirinae (order Nidovirales) is composed of positive-sense RNA viruses primarily found in reptiles. S
Authors
Steven B Tillis, Jillian M. Josimovich, Melissa A. Miller, Hoon-Hanks Laura L., Arik M. Hartmann, Natalie M. Claunch, Marley E. Iredale, Tracey D. Logan, Amy A. Yackel Adams, Ian A. Bartoszek, John S. Humphrey, Bryan M. Kluever, Mark D. Stenglein, Robert Reed, Christina M. Romagosa, James FX. Wellehan Jr., Robert J. Ossiboff

Climate-modulated range expansion of reef-building coral communities off southeast Florida during the late Holocene

The Holocene reefs off southeast Florida provide unique insights into the biogeographical and ecological response of western Atlantic coral reefs to past climate change that can be used to evaluate future climate impacts. However, previous studies have focused on millennial-scale change during the stable mid-Holocene, making it difficult to make inferences about the impact of shorter-term variabil

Authors
Alex B. Modys, Anton E. Olenik, Richard A. Mortlock, Lauren Toth, William F. Precht

Estimating reproductive and juvenile survival rates when offspring ages are uncertain: A novel multievent mark-resight model with beluga whale case study

Understanding the survival and reproductive rates of a population is critical to determining its long-term dynamics and viability. Mark-resight models are often used to estimate these demographic rates, but estimation of survival and reproductive rates is challenging, especially for wide-ranging, patchily distributed, or cryptic species. In particular, existing mark-resight models cannot accommoda
Authors
Gina K Himes Boor, Tamara L McGuire, Amanda J. Warlick, Rebecca L. Taylor, Sarah J. Converse, John R McClung, Amber D Stephens

Defining the Hoek-Brown constant mi for volcanic lithologies

The empirical Hoek-Brown failure criterion is a well-known and commonly used failure criterion for both intact rocks and rock masses, especially in geological engineering. The intact criterion is calculated using experimental triaxial compression test results on intact samples while the rock mass criterion modifies the intact strength using quantified measures of the rock mass quality. The Hoek-Br
Authors
Marlène C. Villeneuve, Michael J. Heap, Lauren N. Schaefer

Landscape characteristics influence projected growth rates of stream-resident juvenile salmon in the face of climate change in the Kenai River watershed, south-central Alaska

ObjectiveClimate change is affecting the distribution and productivity of Pacific salmon throughout their range. At high latitudes, warmer temperatures have been associated with increased freshwater growth of juvenile salmon, but it is not clear how long this trend will continue before further warming leads to reduced growth. To explore the potential influence of climate warming on juvenile Chinoo
Authors
B. E. Meyer, M. S. Wipfli, E. R. Schoen, D. J. Rinella, Jeffrey A. Falke

Geochemistry and fluxes of gases from hydrothermal features at Newberry Volcano, Oregon, USA

We present the chemical and isotopic compositions of gases and fluxes of CO2 from the hydrothermal features of Newberry Volcano, a large composite volcano located in Oregon's Cascade Range with a summit caldera that hosts two lakes, Paulina and East Lakes. Gas samples were collected from 1982 to 2021 from Paulina Hot Springs (PHS) on the shore of Paulina Lake, East Lake Hot Springs (ELHS) on the s
Authors
Jennifer L. Lewicki, William C. Evans, Steven E. Ingebritsen, Laura E. Clor, Peter J. Kelly, Sara Peek, Robert A. Jensen, Andrew Hunt

Future direction of fuels management in sagebrush rangelands

Sagebrush ecosystems in the United States have been declining since EuroAmerican settlement, largely due to agricultural and urban development, invasive species, and altered fire regimes, resulting in loss of biodiversity and wildlife habitat. To combat continued conversion to undesirable ecological states and loss of habitat to invasive species fueled by frequent fire, a variety of fuel treatment
Authors
Douglas J. Shinneman, Eva Strand, Mike Pellant, John T. Abatzoglou, Mark W. Brunson, Nancy Glenn, Julie A. Heinrichs, Mojtaba Sadegh, Nicole Vaillant

Assigning causality to events in the Holocene record of coral reefs

The uncemented reef-frameworks of Pacific Panamá, which have been dominated throughout the Holocene by branching corals of the genus Pocillopora, experienced a hiatus in vertical accretion lasting c. 2300 years, beginning c. 4100 years ago. The hiatus has been attributed to an increase in variability of the El Niño–Southern Oscillation (ENSO). We tested the alternative hypothesis that the hiatus w
Authors
Victor Rodriguez-Ruano, Lauren Toth, Richard B. Aronson

Modeling the dynamic penetration depth of post-1950s water in unconfined aquifers using environmental tracers: Central Valley, California

The penetration depth of post-1950s recharge (D-1950) in aquifers is a marker that is frequently used to identify groundwater that is susceptible to anthropogenic contamination. Here, we compute D-1950 values at wells, interpolate them in space, and project them across time to map the moving front of modern recharge in four dimensions in the Central Valley aquifer system, California, USA. Tracers
Authors
Kirsten Faulkner, Bryant Jurgens, Stefan Voss, Danielle Dupuy, Zeno Levy

Nonlethal tools to identify mass ovarian follicular atresia in Burbot

Skipped spawning, or variation in spawning periodicity, occurs in many annual spawning fish species and is an important consideration for population management. We assessed plasma sex steroid concentrations and measured gonad size and ovarian follicle diameter as metrics to nonlethally identify mass ovarian follicular atresia, which may contribute to skipped spawning in Burbot Lota lota. We mainta
Authors
Lauren M. McGarvey, Jason E. Ilgen, Christopher S. Guy, Jason G. McLellan, Molly A. H. Webb

Maladaptive nest-site selection and reduced nest survival in female sage-grouse following wildfire

Increased wildfire frequency and associated replacement of sagebrush (Artemisia spp.) with invasive annual grasses contribute to declines of greater sage-grouse (Centrocercus urophasianus; hereafter, sage-grouse) populations across the Great Basin. However, little is known about wildfire effects on sage-grouse nest-site selection and nest survival, which can influence population persistence. The p
Authors
Ian F. Dudley, Peter S. Coates, Brian G. Prochazka, Dawn M. Davis, Scott C. Gardner, David J. Delehanty