Search Results

Airborne radiometric surveys use passive geophysical techniques to characterize geochemical variations at or near earth’s surface. These methods have been used for a variety of mapping applications, including mineral resource evaluation. However, detailed characterization of smaller geologic targets, including mine waste features, requires flying at lower altitudes and with tighter...

A high-resolution Earth Mapping Resources Initiative airborne geophysical survey was flown in the southwest North American porphyry copper province to improve bedrock geologic maps and to identify areas that have unrecognized critical mineral resource potential. During the review of the aeromagnetic data, a distinctly monopolar-shaped, negative magnetic anomaly was observed...

The predictive accuracy of regional hydrologic models often varies across both time and space. Interpreting relationships between watershed characteristics, hydrologic regimes, and model performance can reveal potential areas for model improvement. In this study, we use machine learning to assess model performance of a regional hydrologic model to forecast the...

The warm deserts of North America are characterized by diverse environments that include the transition zone between tropical and temperate regions on the continent. This vast region includes the Sonoran and Chihuahuan deserts, which have different precipitation regimes and are composed of different floras and faunas, separated by the Cochise...

The drivers of population dynamics are a primary interest of ecologists, and predicting the consequences of climate variability on wildlife populations benefits from an understanding of how weather causes variation in the vital rates of populations. Given recent and projected extremes in annual precipitation in the Sierra Nevada of California,...

ObjectiveHorseshoe crabs Limulus polyphemus play a vital role in the Delaware Bay ecosystem. The migratory stopover of several shorebird species occurs during the horseshoe crab spawning season, and the eggs of horseshoe crabs provide an essential food source to fuel their northward migration to breeding areas. High commercial fishery use of horseshoe...

ContextInterspecific interactions shape ecological communities, influence community dynamics, and drive co-evolution. Despite their ecological significance, predation and competition remain understudied in plains spotted skunks (Spilogale interrupta), a species of conservation concern. Clarifying how predator management influences their occurrence is crucial for effective conservation.AimsWe investigated how coyote (Canis latrans)...

We investigate patterns of cumulative offsets on the faults that ruptured in 2019 and along the Garlock Fault in the Ridgecrest region, California using recently published gravity and aeromagnetic data. We also examine the relationship of basin structure and bedrock structure to the 2019 M7.1 Ridgecrest earthquake ruptures (Fig. 1A),...

BackgroundFor migratory fishes, habitat selection in dimensions of temperature and depth may be jointly used to define the bathythermal niche. Seasonal and long-term changes in the availability of bathythermal habitat can cause behavioral responses that have consequences for managing interjurisdictional fisheries that target migratory fishes. Management of such...

The use of winter cover crops and conservation tillage are agricultural practices promoted to reduce nutrient and sediment loss from cropland, improve soil health, increase infiltration, and support farm nutrient cycling and ecosystem services. However, environmental performance of these practices is variable in the working farm landscape. The Lower Chesapeake...

Natural history museum records may provide unique information on the distribution of species that can supplement survey data collected by resource managers. However, there can be challenges to using museum data for analyses, such as spurious geographic information, misidentifications, and incorrect labeling. Museum records have been centralized...

Ecological systems can undergo large changes and regime shifts that are either catastrophic, neutral, or desirable. Rivers worldwide have recently undergone desirable regime shifts related to re-oligotrophy, which is a notable and ongoing reduction in concentrations of total suspended solids (TSS), total N, total P, or phytoplankton. For example, the...

The U.S. Geological Survey (USGS) periodically releases updates to National Seismic Hazard Model (NSHM) for the United States and its territories leveraging current scientific knowledge and methodologies to guide public policy, building codes, and risk assessments regarding potential ground shaking due to earthquakes...

Data describing habitat suitability are crucial for implementing effective conservation planning but are often lacking at regional and continental scales. We address this gap for 4 bat species that are listed, proposed for listing, or under Endangered Species Act listing review by highlighting a framework for estimating summer roost suitability...

We needed to evaluate available orbital data of NASA’s Volatiles Investigating Polar Exploration Rover (VIPER) mission area in order to derive a variety of maps to help the science team identify scientifically interesting places for the rover to visit and to provide scientific context for our mission....

Secretive marsh birds experienced precipitous declines due to losses in wetland habitat across North America. However, from 1998 to 2004, wetland area increased, and between 2009 and 2019, the extent of emergent wetlands did not significantly decrease. This raises the question: how did secretive marsh birds, which...

The coastal Cactus Wren (Campylorhynchus brunneicapillus) persists in small and fragmented populations throughout southern California that are subject to genetic drift and inbreeding. We combined individual banding and resighting data and genotyped individuals at 22 microsatellite loci to assess whether heterozygosity was associated with survival across three...

Accurately characterizing 3D fault geometry is vital for improving our understanding of earthquake behavior and informing the development of seismic hazard models. Despite their importance, subsurface fault structures tend to be poorly constrained because of limitations in observational data. Improvements to the seismic networks and earthquake detection algorithms have increased...

ABSTRACTObjectiveAlthough most facets of Largemouth Bass Micropterus nigricans ecology have been researched, the upper tiers of weight distributions (i.e., ≥3.6 kg; herein, “lunkers”) have received little attention due to the challenges of collecting sufficient sample sizes. Our aim was to estimate Largemouth Bass recruitment to higher...

BackgroundTimely information on wildfire burn severity is critical to assess and mitigate potential post-fire impacts on soils, vegetation, and hillslope stability. Tracking individual fire spread and intensity using satellite active fire data provides a pathway to near real-time (NRT) information. Here, we generated a large database (n = 2177) of wildfire events...

In urban areas, floodplain restoration is gaining prominence as a strategy for restoring the natural functions of floodplain ecosystems and reducing flood risk. This has spurred research into potential interactions between floodwaters, the hyporheic zone, and the floodplain aquifer. An urban restored stream in Wisconsin, USA, was used as a...

Automation using deep learning methods is a useful alternative to manual methods of petrographic segmentation, but often requires user familiarity with coding and/or algorithms. We examine the DragonflyTM program's deep learning tools for application by users with a variety of skill levels as a method for petrographic image segmentation. An...

Maars pose considerable hazards due to their more explosive nature (compared with more common scoria cones) and likelihood that eruptions produce pyroclastic surges. Blue Lake crater is a maar in the Oregon High Cascades that erupted within the last 3000 years, making it one of the youngest eruptions in the Oregon...

ContextCheatgrass (Bromus tectorum L.) is a problem across the western United States, where it outcompetes and replaces native grass species, alters habitats, and increases the risk of wildfires. Cheatgrass greens up earlier in the growing season compared to native grasses, making it classifiable with multi-temporal and multi-spectral remote sensing.ObjectivesWe mapped cheatgrass...

The Pacific walrus (Odobenus rosmarus divergens) has a single, panmictic stock that ranges across the Bering and Chukchi Seas. However, its seasonal distribution is incompletely described, particularly in autumn when herds gather on shore, and abundance is of interest to management entities. We monitored walrus herds using satellite imagery on...