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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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Variability in prion protein genotypes by spatial unit to inform susceptibility to chronic wasting disease Variability in prion protein genotypes by spatial unit to inform susceptibility to chronic wasting disease
Chronic wasting disease (CWD) is a fatal encephalopathy affecting North American cervids. Certain alleles in a host’s prion protein gene are responsible for reduced susceptibility to CWD. We assessed for the first time variability in the prion protein gene of elk (Cervus canadensis) present in Pennsylvania, United States of America, a reintroduced population for which CWD cases have...
Authors
Alberto Fameli, Jessie Edson, Jeremiah E. Banfield, Christopher S. Rosenberry, W. David Walter
Climate change alters aging patterns of reservoir aquatic habitats Climate change alters aging patterns of reservoir aquatic habitats
Two slow-moving developments are threatening reservoir aquatic habitats globally: aging and climate change. These events are projected to transform reservoir aquatic habitats in various and often unpredictable ways. Aging affects in-lake habitats directly, whereas climate change affects both in-lake and off-lake conditions. Climate change is expected to accelerate and, in some instances...
Authors
Leandro E. Miranda, N.M. Faucheux
Lake trout (Salvelinus namaycush) otoliths indicate effects of climate and lake morphology on growth patterns in Arctic lakes Lake trout (Salvelinus namaycush) otoliths indicate effects of climate and lake morphology on growth patterns in Arctic lakes
Climate change is occurring rapidly in the Arctic, and an improved understanding of the response of aquatic biota and ecosystems will be important for this data-limited region. Here, we applied biochronology techniques and mixed-effects modelling to assess relationships among growth increments found on lake trout (Salvelinus namaycush) otoliths (N = 49) captured from 13 lakes on the...
Authors
Eric Torvinen, Jeffrey A. Falke, Christopher D. Arp, Benjamin M. Jones, Matthew S. Whitman, Christian E. Zimmerman
Influence of riparian thinning on trophic pathways supporting stream food webs in forested watersheds Influence of riparian thinning on trophic pathways supporting stream food webs in forested watersheds
Resource managers seek to thin second-growth riparian forests to address multiple stream and riparian management objectives, including enhancing aquatic productivity via light-mediated trophic pathways in watersheds of the Pacific Northwest (USA). However, such increases in aquatic productivity depend on complex food web dynamics that link riparian forests and streams. To evaluate how...
Authors
David A. Roon, Jason B. Dunham, J. Ryan Bellmore, Deanna H. Olson, Bret C. Harvey
New strategies for characterizing genetic structure in wide-ranging, continuously distributed species: a Greater Sage-grouse case study New strategies for characterizing genetic structure in wide-ranging, continuously distributed species: a Greater Sage-grouse case study
Characterizing genetic structure across a species’ range is relevant for management and conservation as it can be used to define population boundaries and quantify connectivity. Wide-ranging species residing in continuously distributed habitat pose substantial challenges for the characterization of genetic structure as many analytical methods used are less effective when isolation by...
Authors
Sara J. Oyler-McCance, Todd B. Cross, Jeffery R. Row, Michael K. Schwartz, Dave E. Naugle, Jennifer A. Fike, Kristopher J. Winiarski, Brad C. Fedy
Partial observability and management of ecological systems Partial observability and management of ecological systems
The actual state of ecological systems is rarely known with certainty, but management actions must often be taken regardless of imperfect measurement (partial observability). Because of the difficulties in accounting for partial observability, it is usually treated in an ad hoc fashion, or simply ignored altogether. Yet incorporating partial observability into decision processes lends a...
Authors
Byron K. Williams, Ellie Brown
Mountain rivers reveal the earthquake hazard of geologic faults in Silicon Valley Mountain rivers reveal the earthquake hazard of geologic faults in Silicon Valley
The 1989, Mw = 6.9 Loma Prieta earthquake resulted in tens of lives lost and cost California almost 3% of its gross domestic product. Despite widespread damage, the earthquake did not clearly rupture the surface, challenging the identification and characterization of these hidden hazards. Here, we show that they can be illuminated by inverting fluvial topography for slip-and moment...
Authors
Felipe Aron, Samuel Johnstone, Andreas Mavrommatis, Robert M. Sare, Frantz Maerten, Jack Loveless, Curtis W Baden, George E. Hilley
Integrated modeling of dynamic marsh feedbacks and evolution under sea-level rise in a mesotidal estuary (Plum Island, MA, USA) Integrated modeling of dynamic marsh feedbacks and evolution under sea-level rise in a mesotidal estuary (Plum Island, MA, USA)
Around the world, wetland vulnerability to sea-level rise (SLR) depends on different factors including tidal regimes, topography, creeks and estuary geometry, sediment availability, vegetation type, etc. The Plum Island estuary (PIE) is a mesotidal wetland system on the east coast of the United States. This research applied a newly updated Hydro-MEM (integrated hydrodynamic-marsh) model...
Authors
Karim Alizad, James T. Morris, Matthew V. Bilskie, Davina Passeri, Scott C. Hagen
Climate change weakens the impact of disturbance interval on the growth rate of natural populations of Venus flytrap Climate change weakens the impact of disturbance interval on the growth rate of natural populations of Venus flytrap
Disturbances elicit both positive and negative effects on organisms; these effects vary in their strength and their timing. Effects of disturbance interval (i.e., the length of time between disturbances) on population growth will depend on both the timing and strength of positive and negative effects of disturbances. Climate change can modify the relative strengths of these positive and...
Authors
Allison M Louthan, Melina Keighron, Elsita Kiekebusch, Heather Cayton, Adam J. Terando, William F. Morris
A machine learning approach to predicting equilibrium ripple wavelength A machine learning approach to predicting equilibrium ripple wavelength
Sand ripples are geomorphic features on the seafloor that affect bottom boundary layer dynamics including wave attenuation and sediment transport. We present a new equilibrium ripple predictor using a machine learning approach that outputs a probability distribution of wave-generated equilibrium wavelengths and statistics including an estimate of ripple height, the most probable ripple...
Authors
Ryan E. Phillip, Allison M. Penko, Margaret L. Palmsten, Carter B. DuVal
Sedimentary organics in Glen Torridon, Gale Crater, Mars: Results from the SAM instrument suite and supporting laboratory analyses Sedimentary organics in Glen Torridon, Gale Crater, Mars: Results from the SAM instrument suite and supporting laboratory analyses
The Sample Analysis at Mars (SAM) suite instrument on board NASA's Curiosity rover has characterized the inorganic and organic chemical composition of seven samples from the Glen Torridon (GT) clay-bearing unit. A variety of organic molecules were detected with SAM using pyrolysis (up to ∼850°C) and wet chemistry experiments coupled with evolved gas analysis (EGA) and gas chromatography...
Authors
Maeva Millan, Amy Williams, Amy McAdam, Jennifer Eigenbrode, A. Steele, C Freissinet, D. P. Glavin, C. Szopa, A. Buch, Roger E. Summons, J. M. T. Lewis, G. M. Wong, C. H. House, B. Sutter, O. McIntosh, A. B. Bryk, H. B. Franz, C. Pozarycki, J. C. Stern, R. Navarro-Gonzalez, R. H. Williams, D. P. Archer, V. Fox, Kristen A. Bennett, S. Teinturier, C. Malespin, S. S. Johnson, P. R. Mahaffy
Forecasting explosions at Sinabung Volcano, Indonesia, based on SO2 emission rates Forecasting explosions at Sinabung Volcano, Indonesia, based on SO2 emission rates
Dome-building volcanic eruptions are often associated with frequent Vulcanian explosions, which constitute a substantial threat to proximal communities. One proposed mechanism driving such explosions is the sealing of the shallow volcanic system followed by pressurization due to gas accumulation beneath the seal. We investigate this hypothesis at Sinabung Volcano (Sumatra, Indonesia)...
Authors
Syegi Kunrat, Christoph Kern, Hilma Alfianti, Allan Lerner