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Large carnivores are capable of consuming substantial biomasses that can significantly alter their body mass and condition over short periods. Here we examine the intra-seasonal variation of polar bear (Ursus maritimus Phipps, 1774) body mass, energy intake, and condition in the spring from two subpopulations. We evaluate the biological and temporal...

A species' distribution depends on its tolerance to environmental conditions. These conditions are defined by a minimum, maximum, and optimal ranges of single and combined factors. Forays into environmental conditions outside the minimum or maximum tolerance of a species (i.e., thresholds) are predicted to have large effects on a species'...

Beginning in 2020, the National Park Service (NPS) began a systematic effort to document the occurrence of stratotypes exposed within, partially within, and near NPS administrative boundaries. The NPS stratotype inventory project represents an important component of a geologic resource inventory, as these designations are vital to our national geologic...

In subduction zones worldwide, seafloor pressure data are used to observe tectonic deformation, particularly from megathrust earthquakes and slow slip events (SSEs). However, such measurements are also sensitive to oceanographic circulation-generated pressures over a range of frequencies that conflate with tectonic signals of interest. Using seafloor pressure and temperature data...

Effective, practical options for managing disease in wildlife populations are limited, especially after diseases become established. Removal strategies (e.g., hunting or culling) are used to control wildlife diseases across a wide range of systems, despite conflicting evidence of their effectiveness. This is especially true for chronic wasting disease (CWD), an...

Among the most immediate drivers of American burying beetle (Nicrophorus americanus Olivier) declines, nontarget toxicity to pesticides is poorly understood. Acute, episodic exposure to neonicotinoid insecticides at environmentally relevant concentrations is linked to negative impacts on beneficial terrestrial insect taxa. Beyond mortality, behavioral indicators of toxicity are often better suited to...

We hypothesized that bighorn sheep ewes with chronic nasal Mycoplasma ovipneumoniae carriage are the source of infection that results in fatal lamb pneumonia. We tested this hypothesis in captive bighorn ewes at two study facilities over a 5-year period, by identifying carrier ewes and then comparing lamb fates in groups that did...

Wildfires can have a profound impact on hydrosedimentary interactions, or the relationship between sediment and runoff, in forested headwater streams. Quantification of sediment-runoff dynamics at the event scale is integral for understanding source areas and transport of suspended-sediment through a watershed following wildfire. Here we used high-frequency turbidity and stream...

More landscapes require restoration than can feasibly be treated, and so decision-support tools to prioritize areas for treatment are needed. Moreover, restoration is complicated by the threat of biological invasion in disturbed areas, and so indicators of ecosystem resistance to invasion and resilience to disturbance (hereafter R&R) are important...

Traditional conservation efforts have centred on safeguarding individual species, but these strategies have limitations in a world where entire ecosystems are rapidly changing. Ecosystem conservation can maintain critical ecological functions, but often lacks the detail necessary for the effective conservation of threatened or endangered species. The conservation of such species...

This study assesses the impacts of five proposed restoration actions at Little Dauphin Island, a low-lying relic spit in a semi-enclosed bay system on the Alabama coast. A Delft3D model is developed to simulate annual scale (five-year) sediment transport and resulting bed level changes. The model is validated with observed...

Microbial processing of atmospheric nitrogen (N) deposition regulates the retention and mobilization of N in soils, with important implications for water quality. Understanding the links between N deposition, microbial communities, N transformations, and water quality is critical as N deposition shifts toward reduced N and remains persistently high in many...

Strong earthquakes along subduction zones are often devastating events, but sparse records along some tectonic margins limit our understanding of seismic hazards. Constraining shaking intensities is critical, especially in subduction zones with infrequent but large-magnitude earthquakes like the Cascadia Subduction Zone (CSZ), where the lack of recorded ground motions has...

The degree of organic sulfurization is broadly relevant yet underreported. We present a statistically significant correlation between whole rock S/Fe and the measured degree of organic sulfurization in the thermally immature Cenomanian–Turonian Eagle Ford Group. This relationship shows a sink switch for sulfur from pyrite to organic matter. Excess iron...

Introduction The widely used National Land Cover Database (NLCD) has long been the foundational land cover source for scientists, resource managers, and decision makers across the United States.In 2024, a reinvention as Annual NLCD added the key improvement of annual time steps to show decades of change at a higher frequency...

This is the second volume in the U.S. Geological Survey (USGS) series of reports on stratigraphy entitled “Stratigraphic Notes,” which consists of short papers that highlight stratigraphic studies, changes in stratigraphic nomenclature, and explanations of stratigraphic names and concepts used on published geologic maps. “Stratigraphic Notes” is a long-term (multiyear),...

Earthquakes are a rapid-onset hazard where advance planning and learning plays a key role in mitigating injuries and death to individuals. Recent advances in earthquake detection have resulted in the development of earthquake early warning (EEW) systems. These systems can provide advance warning to predetermined geographic regions that an earthquake...

Identifying populations at highest risk from climate change is a critical component of conservation efforts. However, vulnerability assessments are usually applied at the species level, even though intraspecific variation in exposure, sensitivity and adaptive capacity play a crucial role in determining vulnerability. Genomic data can inform intraspecific vulnerability by identifying...

Hillslope sediment transport processes such as bioturbation, rainsplash, and granular mechanics occur across the entire planet. Yet, it remains uncertain how these small-scale processes act together to shape landscapes. Longstanding hillslope diffusion theory posits that hillslope processes are spatially limited, whereas new concepts of nonlocal sediment transport argue otherwise. However,...

Conservationists are increasingly leveraging systematic conservation planning (SCP) to inform restoration actions that enhance biodiversity. However, restoration frequently drives ecological transformations at local scales, potentially resulting in trade-offs among wildlife species and communities. The Conservation Interactions Principle (CIP), coined more than 15 years ago, cautions SCP practitioners regarding the importance of jointly and...

Many mountain belts are built through repeated collision, and in the case of orogenies closely spaced in time, determining when one orogeny ends and another begins can be challenging. The southern Appalachian mountains were formed by three mountain-building events closely spaced in time, including the Taconic (ca. 480–440 Ma), Neoacadian...

Subsidy–stress gradients offer a useful framework for understanding ecological responses to perturbation and may help inform ecological metrics in highly modified systems. Historic, region-wide shifts from bottomland hardwood forest to row crop agriculture can cause positively skewed impact gradients in alluvial plain ecoregions, resulting in tolerant organisms that typically exhibit...

The chronology of mafic eruptions and their temporal relation to rhyolitic volcanism in the Yellowstone Plateau volcanic field are poorly known, thereby limiting our understanding of the way(s) in which mafic magmatism drives rhyolitic activity. To address this, we measured 40Ar/39Ar eruption ages on 13 mafic samples collected from Henrys Fork...

Despite the long-standing recognition that animals partition activities, for example, across different periods of the day, understanding of how habitat selection varies according to specific temporal periods or behavioral activities remains limited for most species. For example, although much of the animal kingdom is nocturnally active, studies that characterize nocturnal...

In the arid western Snake River Plain around the City of Mountain Home, Idaho, declining groundwater levels concern agricultural, municipal, and other water users who rely on groundwater for sustenance because surface-water resources are limited. The U.S. Geological Survey developed this hydrogeologic framework to provide an updated characterization of groundwater...