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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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Agkistrodon conanti (Florida Cottonmouth) and Python bivittatus (Burmese Python). Diet and Predation Agkistrodon conanti (Florida Cottonmouth) and Python bivittatus (Burmese Python). Diet and Predation
Python bivittatus is established in the Greater Everglades Ecosystem in southern Florida, USA. Documented predators on pythons in Florida include Alligator mississippiensis (American Alligator; Snow et al. 2006. Herpetol. Rev. 37:81–81), Drymarchon couperi (Gulf Coast Indigo Snake; Andreadis et al. 2018. Herpetol. Rev. 49:341–342), Lynx rufus (Bobcat; McCollister et al. 2021. Southeast...
Authors
Ian A. Bartoszek, Gretchen Erika Anderson, Ian Easterling, Jillian Maureen Josimovich, Alex Furst, Frank N. Ridgley, Austin Lee Fitzgerald, Amy A. Yackel Adams, Andrea Faye Currylow
Representing plant diversity in land models: An evolutionary approach to make ‘Functional Types’ more functional Representing plant diversity in land models: An evolutionary approach to make ‘Functional Types’ more functional
Plants are critical mediators of terrestrial mass and energy fluxes, and their structural and functional traits have profound impacts on local and global climate, biogeochemistry, biodiversity, and hydrology. Yet Earth System Models (ESMs), our most powerful tools for predicting the effects of humans on the coupled biosphere-atmosphere system, simplify the incredible diversity of land...
Authors
Leander D.L. Anderegg, Daniel Mark Griffith, Jeannine Cavender-Bares, William J. Riley, Joseph A. Berry, Todd E. Dawson, Christopher J. Still
Relational database for horizontal‐to‐vertical spectral ratios Relational database for horizontal‐to‐vertical spectral ratios
Frequency‐dependent horizontal‐to‐vertical spectral ratios (HVSRs) of Fourier amplitudes from three‐component recordings can provide useful information for site response modeling. However, such information is not incorporated into most ground‐motion models, including those from Next‐Generation Attenuation projects, which instead use the time‐averaged shear‐wave velocity (VSVS) in the...
Authors
Pengfei Wang, Paolo Zimmaro, Tristan E Buckreis, Tatiana Gospe, Scott J Brandenberg, Sean Kamran Ahdi, Alan Yong, Jonathan P. Stewart
Reservoir attributes display cascading spatial patterns along river basins Reservoir attributes display cascading spatial patterns along river basins
Considering reservoirs as linear fragments in a basin's river network could improve understanding, predictability, and management efficiency. We looked for general cascading spatial patterns across five categories of reservoir attributes: land cover, morphology and hydrology, fish habitat, fish assemblages, and fisheries. Attributes were pulled from various databases for large reservoirs...
Authors
N.M. Faucheux, A.R. Sample, C.A. Aldridge, D.M. Norris, C. Owens, Victoria R. Starnes, S. VanderBloemen, Leandro E. Miranda
Emerging control strategies for integrated pest management of invasive carps Emerging control strategies for integrated pest management of invasive carps
Invasive carps are ecologically and economically problematic fish species in many large river basins in the United States and pose a threat to aquatic ecosystems throughout much of North America. Four species of invasive carps: black carp (Mylopharyngodon piceus), grass carp (Ctenopharyngodon idella), silver carp (Hypophthalmichthys molitrix) and bighead carp (Hypophthalmichthys nobilis)...
Authors
Aaron R. Cupp, Marybeth K. Brey, Robin D. Calfee, Duane Chapman, Richard A. Erickson, Jesse Robert Fischer, Andrea K. Fritts, Amy E. George, P. Ryan Jackson, Brent C. Knights, Gavin N. Saari, Patrick Kocovsky
Modeling the occurrence of M ∼ 5 caldera collapse-related earthquakes in Kīlauea volcano, Hawai'i Modeling the occurrence of M ∼ 5 caldera collapse-related earthquakes in Kīlauea volcano, Hawai'i
During the 2018 Kīlauea eruption and caldera collapse, M ∼ 5 caldera collapse earthquakes occurred almost daily from mid-May until the beginning of August. While caldera collapses happen infrequently, the collapse-related seismicity damaged nearby structures, and so these events should be included in a complete seismic hazard assessment. Here, we present an approach to forecast the...
Authors
Andrea L. Llenos, Andrew J. Michael
A quantitative soil-geomorphic framework for developing and mapping ecological site groups A quantitative soil-geomorphic framework for developing and mapping ecological site groups
Land management decisions need context about how landscapes will respond to different circumstances or actions. As ecologists’ understanding of nonlinear ecological dynamics has evolved into state-and-transition models (STMs), they have put more emphasis on defining and mapping the soil, geomorphological, and climate parameters that mediate these dynamics. The US Department of...
Authors
Travis W. Nauman, Samuel S Burch, Joel T. Humphries, Anna C. Knight, Michael C. Duniway
Demographic response of brown treesnakes to extended population suppression Demographic response of brown treesnakes to extended population suppression
From a management perspective, reptiles are relatively novel invasive taxa. Few methods for reptile control have been developed and very little is known about their effectiveness for reducing reptile populations, particularly when the goal is eradication. Many reptiles, and especially snakes, are cryptic, secretive, and undergo extended periods of inactivity, traits that decrease...
Authors
Melia G. Nafus, Shane R. Siers, Brenna A. Levine, Zachary C. Quiogue, Amy A. Yackel Adams
Reconstructing the paleoceanographic and redox conditions responsible for variations in uranium content in North American Devonian black shales Reconstructing the paleoceanographic and redox conditions responsible for variations in uranium content in North American Devonian black shales
The uranium (U) content, and more recently, the ratio between 238U and 235U in black shales are commonly applied as a proxy to determine redox conditions and infer organic-richness. Uranium contents typically display a linear relationship with total organic carbon (TOC) in shales. This relationship is due to the processes and mechanisms responsible for the incorporation of U into the...
Authors
Michelle L. Abshire, Natascha Riedinger, John M. Clymer, Clint Scott, Silke Severmann, Stephen J. Romaniello, James O. Puckette
Synthetic evaluation of infrasonic multipole waveform inversion Synthetic evaluation of infrasonic multipole waveform inversion
Acoustic source inversions estimate the mass flow rate of volcanic explosions or yield of chemical explosions and provide insight into potential source directionality. However, the limitations of applying these methods to complex sources and their ability to resolve a stable solution have not been investigated in detail. We perform synthetic infrasound waveform inversions that use 3-D...
Authors
Alexandra M. Iezzi, Robin S Matoza, David Fee, Keehoon Kim, A.D. Jolly
Geochemical insights into formation of enigmatic ironstones from Rio Grande rise, South Atlantic Ocean Geochemical insights into formation of enigmatic ironstones from Rio Grande rise, South Atlantic Ocean
Rio Grande Rise (RGR) is an intraplate oceanic elevation in the South Atlantic Ocean that formed at a hotspot on the Mid-Atlantic Ridge during the Cretaceous. In spreading center and hotspot environments, ironstones form mainly by biomineralization of reduced Fe from hydrothermal fluids or oxidation of sulfide deposits. However, RGR has been considered aseismic and volcanically inactive...
Authors
Mariana Benites, James R. Hein, Kira Mizell, Kenneth A. Farley, Jonathon Treffkorn, Luigi Jovane
Effects of salinity and a glucocorticoid antagonist, RU486, on waterborne aldosterone and corticosterone of northern leopard frog larvae Effects of salinity and a glucocorticoid antagonist, RU486, on waterborne aldosterone and corticosterone of northern leopard frog larvae
Increased salinity is an emerging contaminant of concern for aquatic taxa. For amphibians exposed to salinity, there is scarce information about the physiological effects and changes in osmoregulatory hormones such as corticosterone (CORT) and aldosterone (ALDO). Recent studies have quantified effects of salinity on CORT physiology of amphibians based on waterborne hormone collection...
Authors
Brian J. Tornabene, Creagh W Breuner, Blake R. Hossack, Erica J Crespi