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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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Biofouling of a unionid mussel by dreissenid mussels in nearshore zones of the Great Lakes Biofouling of a unionid mussel by dreissenid mussels in nearshore zones of the Great Lakes
In North America, native unionid mussels are imperiled due to factors such as habitat degradation, pollution, and invasive species. One of the most substantial threats is that posed by dreissenid mussels, which are invasive mussels that attach to hard substrates including unionid shells and can restrict movement and feeding of unionids. This dreissenid mussel biofouling of unionids...
Authors
James H. Larson, Sean Bailey, Mary Anne Evans
Optimizing surveys of fall-staging geese using aerial imagery and automated counting Optimizing surveys of fall-staging geese using aerial imagery and automated counting
Ocular aerial surveys allow efficient coverage of large areas and can be used to monitor abundance and distribution of wild populations. However, uncertainty around resulting population estimates can be large due to difficulty in visually identifying and counting animals from aircraft, as well as logistical challenges in estimating detection probabilities. Photographic aerial surveys can...
Authors
Emily L. Weiser, Paul L. Flint, Dennis K Marks, Brad S Shults, Heather M. Wilson, Sarah J. Thompson, Julian B. Fischer
Estimates of k0 and effects on ground motions in the San Francisco Bay area Estimates of k0 and effects on ground motions in the San Francisco Bay area
Ground‐motion studies are a key component of seismic hazard analyses and often rely on information of the source, path, and site. Extensive research has been done on each of these parameters; however, site‐specific studies are of particular interest to seismic hazard studies, especially in the field of earthquake engineering, as near‐site conditions can have a significant impact on the...
Authors
Tara Nye, Valerie J. Sahakian, Elias King, Annemarie S. Baltay Sundstrom, Alexis Klimasewski
A regionally varying habitat model to inform management for greater sage-grouse persistence across their range A regionally varying habitat model to inform management for greater sage-grouse persistence across their range
Identifying habitat needs for species with large distributions is challenging because species-habitat associations may vary across scales and regions (spatial nonstationarity). Furthermore, management efforts often cross jurisdictional boundaries, complicating the development of cohesive conservation strategies among management entities. The greater sage-grouse (Centrocercus urophasianus...
Authors
Gregory T. Wann, Nathan D. Van Schmidt, Jessica E. Shyvers, Bryan C. Tarbox, Megan M. McLachlan, Michael S. O’Donnell, Anthony J Titolo, Peter S. Coates, David R. Edmunds, Julie A. Heinrichs, Adrian P. Monroe, Cameron L. Aldridge
Harnessing island–ocean connections to maximize marine benefits of island conservation Harnessing island–ocean connections to maximize marine benefits of island conservation
Islands support unique plants, animals, and human societies found nowhere else on the Earth. Local and global stressors threaten the persistence of island ecosystems, with invasive species being among the most damaging, yet solvable, stressors. While the threat of invasive terrestrial mammals on island flora and fauna is well recognized, recent studies have begun to illustrate their...
Authors
Stuart A. Sandin, Penny A. Becker, Ceiba Becker, Kate Brown, Natalia G. Erazo, Cielo Figuerola, Robert N. Fisher, Alan M. Friedlander, Tadashi Fukami, Nicholas A. J. Graham, Daniel S. Gruner, Nick D. Holmes, Wieteke A. Holthuijzen, Holly P. Jones, Mariela Rios, Araceli Samaniego, Wes Sechrest, Brice X. Semmens, Hazel E. Thornton, Rebecca Vega Thurber, Christy Wails, Coral A. Wolf, Brian J. Zgliczynski
A channel sampling strategy for measurement of mineral modal and chemical composition of drill cores: Application to lower oceanic crustal rocks from IODP Expedition 345 to the Hess Deep rift A channel sampling strategy for measurement of mineral modal and chemical composition of drill cores: Application to lower oceanic crustal rocks from IODP Expedition 345 to the Hess Deep rift
We report a new sampling strategy for collecting representative samples of drill core. By splitting the core with a diamond saw into working and archive halves, the saw cuttings constitute a “channel” sample, the best subsample from which to obtain an average mineralogical and geochemical composition of a core. We apply this procedure to sampling core of the lower oceanic crust in the...
Authors
Robert P. Wintsch, Romain Meyer, David Bish, Ryan T. Deasy, Toshio Nozaka, Carley Johnson
Precaldera mafic magmatism at Long Valley, California: Magma-tectonic siting and incubation of the Great Rhyolite System Precaldera mafic magmatism at Long Valley, California: Magma-tectonic siting and incubation of the Great Rhyolite System
The iconic volcanic center at Long Valley has released ∼820 km3 of rhyolite in at least 110 eruptions. From 2.2 Ma until 0.23 Ma, products were exclusively rhyolitic, and ∼ 700 km3 were high-silica rhyolite severely depleted in Sr, Ba, and Eu. The rhyolitic interval was preceded by an interval from 3.9 to 2.6 Ma with numerous basalt-andesite-dacite eruptions accompanied by no rhyolite at...
Authors
Edward Hildreth, Judith E. Fierstein, Andrew T. Calvert
Magma storage and transport timescales for the 1959 Kīlauea Iki eruption and implications for diffusion chronometry studies using time-series samples versus tephra deposits Magma storage and transport timescales for the 1959 Kīlauea Iki eruption and implications for diffusion chronometry studies using time-series samples versus tephra deposits
Complex crystal cargo in basaltic eruptions has the potential to yield diverse insights on pre- and syn-eruptive timescales of magma storage and transport. Research on eruption products from the 1959 eruption from Kīlauea Iki Crater at Kīlauea volcano (Hawai‘i) demonstrates that time-series samples collected during an eruption can yield a wealth of information not accessible by studying...
Authors
Kendra J. Lynn, Rosalind L. Helz
Evaluating the sensitivity of multi-dimensional model predictions of salmon habitat to the source of remotely sensed river bathymetry Evaluating the sensitivity of multi-dimensional model predictions of salmon habitat to the source of remotely sensed river bathymetry
Multi-dimensional numerical models are fundamental tools for investigating biophysical processes in aquatic ecosystems. Remote sensing techniques increase the feasibility of applying such models at riverscape scales, but tests of model performance on large rivers have been limited. We evaluated the potential to develop two-dimensional (2D) and three-dimensional (3D) hydrodynamic models...
Authors
Lee R. Harrison, Carl J. Legleiter, Vamsi K Sridharana, Peter Dudley, Miles E. Daniels
Diet composition and overlap for adult walleye, lake whitefish, and yellow perch in Green Bay, Lake Michigan Diet composition and overlap for adult walleye, lake whitefish, and yellow perch in Green Bay, Lake Michigan
Interspecific interactions among walleye Sander vitreus, lake whitefish Coregonus clupeaformis, and yellow perch Perca flavescens in Green Bay could influence the population status of each species, but potential trophic interactions are poorly understood. Our objectives were to determine if diet assemblages for each species and diet overlap among species varied spatially and temporally...
Authors
Lucas D. Koeniga, Daniel J. Dembkowski, Scott P. Hansen, Iyob Tsehaye, Tammie J. Paoli, Troy G. Zorn, Daniel A. Isermann
Energy expenditure of fat in a large herbivore is non-linear over winter Energy expenditure of fat in a large herbivore is non-linear over winter
No abstract available.
Authors
Anna C. Ortega, Tayler N. Lasharr, Matthew J. Kauffman, Kevin L. Monteith
Environmental monitoring for invasive fungal pathogens of ʽŌhiʽa (Metrosideros polymorpha) on the Island of Hawaiʽi Environmental monitoring for invasive fungal pathogens of ʽŌhiʽa (Metrosideros polymorpha) on the Island of Hawaiʽi
The invasive rust Austropuccina psidii was detected in the Hawaiian Islands in 2005 and has become widely established throughout the archipelago in both native and introduced species of Myrtaceae. Initial predictions about the impacts of the fungus on native ʽōhiʽa lehua (Metrosideros polymorpha), a keystone native tree, have not materialized, but there is ongoing concern that...
Authors
Carter T. Atkinson, Kylle Roy