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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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Changes in vegetation structure and gopher tortoise population structure after 17 years of restoration management Changes in vegetation structure and gopher tortoise population structure after 17 years of restoration management

We examined a study plot sampled in the Conecuh National Forest of southern Alabama in 1999 and again in 2016 after stand thinning and persistent prescribed fire were used to improve habitat quality. These management activities were designed, in part, to enhance habitat quality for the gopher tortoise (Gopherus polyphemus), a species considered for protection under the Endangered Species...
Authors
Rebecca C. Pudner, Hardin Waddle, Suzi P. Mersmann, John S. Kush, Craig Guyer, Sharon M. Hermann

Testing a generalizable machine learning workflow for aquatic invasive species on Rainbow Trout (Oncorhynchus mykiss) in northwest Montana Testing a generalizable machine learning workflow for aquatic invasive species on Rainbow Trout (Oncorhynchus mykiss) in northwest Montana

Biological invasions are accelerating worldwide, causing major ecological and economic impacts in aquatic ecosystems. The urgent decision-making needs of invasive species managers can be better met by the integration of biodiversity big data with large-domain models and data-driven products. Remotely sensed data products can be combined with existing invasive species occurrence data via...
Authors
Sean C. Carter, Charles B. van Rees, Brian K. Hand, Clint C. Muhlfeld, Gordon Luikart, John S Kimball

Acute mortality in California tiger salamander (Ambystoma californiense) and Santa Cruz long-toed salamander (Ambystoma macrodactylum croceum) caused by Ribeiroia ondatrae (Class: Trematoda) Acute mortality in California tiger salamander (Ambystoma californiense) and Santa Cruz long-toed salamander (Ambystoma macrodactylum croceum) caused by Ribeiroia ondatrae (Class: Trematoda)

In early September 2019, a morbidity and mortality event affecting California tiger salamanders (Ambystoma californiense) and Santa Cruz long-toed salamanders (Ambystoma macrodactylum croceum) in late stages of metamorphosis was reported at a National Wildlife Refuge in Santa Cruz County, California, U.S.A. During the postmortem disease investigation, severe integumentary metacercarial...
Authors
Saskia Keller, Constance Roderick, Christopher Caris, Daniel A. Grear, Rebecca A. Cole

The effects of ENSO and the North American monsoon on mast seeding in two Rocky Mountain conifer species The effects of ENSO and the North American monsoon on mast seeding in two Rocky Mountain conifer species

We aimed to disentangle the patterns of synchronous and variable cone production (i.e. masting) and its relationship to climate in two conifer species native to dry forests of western North America. We used cone abscission scars to reconstruct ca 15 years of recent cone production in Pinus edulis and Pinus ponderosa, and used redundancy analysis to relate time series of annual cone...
Authors
Andreas Wion, Ian S. Pearse, Kyle C. Rodman, Thomas T. Veblen, Miranda D. Redmond

The ecology and evolution of synchronized reproduction in long-lived plants The ecology and evolution of synchronized reproduction in long-lived plants

Populations of many long-lived plants exhibit spatially synchronized seed production that varies extensively over time, so that seed production in some years is much higher than on average, while in others, it is much lower or absent. This phenomenon termed masting or mast seeding has important consequences for plant reproductive success, ecosystem dynamics and plant–human interactions...
Authors
Mario B. Pesendorfer, Davide Ascoli, Michal Bogdziewicz, Andrew Hacket-Pain, Ian S. Pearse, Giorgio Vacchiano

Machine learning predictions of nitrate in groundwater used for drinking supply in the conterminous United States Machine learning predictions of nitrate in groundwater used for drinking supply in the conterminous United States

Groundwater is an important source of drinking water supplies in the conterminous United State (CONUS), and presence of high nitrate concentrations may limit usability of groundwater in some areas because of the potential negative health effects. Prediction of locations of high nitrate groundwater is needed to focus mitigation and relief efforts. A three-dimensional extreme gradient...
Authors
Katherine Marie Ransom, Bernard T. Nolan, Paul E. Stackelberg, Kenneth Belitz, Miranda S. Fram

Evolution in eruptive style of the 2018 eruption of Veniaminof volcano, Alaska, reflected in groundmass textures and remote sensing Evolution in eruptive style of the 2018 eruption of Veniaminof volcano, Alaska, reflected in groundmass textures and remote sensing

Variable eruptive style and explosivity is common in basaltic to basaltic andesite volcanoes but can have uncertain origins. Veniaminof volcano in the Alaska-Aleutian arc is a frequently active open-vent center, regularly producing Strombolian eruptions and small lava flows from an intracaldera cone within an intracaldera ice cap. The September–December 2018 eruption of Veniaminof...
Authors
Matthew W. Loewen, Hannah R. Dietterich, Nathan Graham, Pavel Izbekof

Modes of climate variability bridge proximate and evolutionary mechanisms of masting Modes of climate variability bridge proximate and evolutionary mechanisms of masting

There is evidence that variable and synchronous reproduction in seed plants (masting) correlates to modes of climate variability, e.g. El Niño Southern Oscillation and North Atlantic Oscillation. In this perspective, we explore the breadth of knowledge on how climate modes control reproduction in major masting species throughout Earth's biomes. We posit that intrinsic properties of...
Authors
Davide Ascoli, Andrew Hacket-Pain, Ian S. Pearse, Giorgio Vacchiano, Susanna Corti, Paolo Davini

Active virus-host interactions at sub-freezing temperatures in Arctic peat soil Active virus-host interactions at sub-freezing temperatures in Arctic peat soil

Background Winter carbon loss in northern ecosystems is estimated to be greater than the average growing season carbon uptake and is primarily driven by microbial decomposers. Viruses modulate microbial carbon cycling via induced mortality and metabolic controls, but it is unknown whether viruses are active under winter conditions (anoxic and sub-freezing temperatures).Results We used...
Authors
Gareth Trubl, Jeffrey A Kimbrel, Jose Liquet-Gonzalez, Erin E. Nuccio, Peter K. Weber, Jennifer Pett-Ridge, Janet K. Jansson, Mark Waldrop, Steve Blazewicz

Understanding mast seeding for conservation and land management Understanding mast seeding for conservation and land management

Masting, the intermittent and synchronous production of large seed crops, can have profound consequences for plant populations and the food webs that are built on their seeds. For centuries, people have recorded mast crops because of their importance in managing wildlife populations. In the past 30 years, we have begun to recognize the importance of masting in conserving and managing...
Authors
Ian S. Pearse, Andreas Wion, Angela Gonzalez, Mario B. Pesendorfer

Effects of hydrologic variability and remedial actions on first flush and metal loading from streams draining the Silverton caldera, 1992–2014 Effects of hydrologic variability and remedial actions on first flush and metal loading from streams draining the Silverton caldera, 1992–2014

This study examined water quality in the upper Animas River watershed, a mined watershed that gained notoriety following the 2015 Gold King mine release of acid mine drainage to downstream communities. Water-quality data were used to evaluate trends in metal concentrations and loads over a two-decade period. Selected sites included three sites on tributary streams and one main-stem site...
Authors
Tanya N Petach, Robert L. Runkel, Rory M. Cowie, Diane M. McKnight

Similarities and differences between two deadly Caribbean coral diseases: White plague and stony coral tissue loss disease Similarities and differences between two deadly Caribbean coral diseases: White plague and stony coral tissue loss disease

For several decades, white plagues (WPDs: WPD-I, II and III) and more recently, stony coral tissue loss disease (SCTLD) have significantly impacted Caribbean corals. These diseases are often difficult to separate in the field as they produce similar gross signs. Here we aimed to compare what we know about WPD and SCTLD in terms of: (1) pathology, (2) etiology, and (3) epizootiology. We...
Authors
Aldo Cróquer, Ernesto Weil, Caroline Rogers
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