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The U.S. Geological Survey (USGS), in collaboration with university, Federal, Tribal, and independent partners, conducts fundamental research on the distribution, vulnerability, and importance of permafrost in arctic and boreal ecosystems. Scientists, land managers, and policy makers use USGS data to help make decisions for development, wildlife habitat, and other needs....

Today’s Earth system challenges are far more complex and urgent than those that existed in 1879 when the USGS was established. Society’s greatest challenges are directly or indirectly linked to major areas of USGS science. Increased pressures on natural resources continue with consequences for national security, food and water availability,...

Individuals living in every region of the world are increasingly vulnerable to negative health outcomes due to extreme heat exposure. Children, in particular, may face long-term consequences associated with heat stress that affect their educational attainment and later life health and well-being. Retrospective individual-level analyses are useful for determining the...

Counts of greater sage-grouse (Centrocercus urophasianus) at leks have been used in harvest management, Endangered Species Act listing decisions, and land management policies for over half a century. Lek count sampling methods focus on counting male sage-grouse at known leks, primarily those observed visually from roads or vantage points, but...

In much of the western Cordillera of North America, the geologic framework of crustal structure generated in the Mesozoic leaves an imprint on later plutonic emplacement, subsequent structural setting, and present landscape morphology. The Merrimac plutons in the northern Sierra Nevada (California, USA) are a...

Tropical montane forests are being lost at an alarming rate but harbor some of the globe’s most unique biodiversity. The Hawaiian archipelago is a prime example of the importance of high elevation forests to species conservation and persistence as they serve...

Ash and surface water samples collected after wildfires in four different geographical locations (California, Colorado, Kansas and Alberta) were analyzed. The ash samples were leached with deionized water, and leachates were concentrated by solid phase extraction and analyzed by liquid chromatography/time-of-flight mass spectrometry. In...

A significantly elevated groundwater salinity zone was identified in the southern part of the Mesilla Valley. This investigation characterized the occurrence, spatial extent, and source of the plume of elevated groundwater salinity using a wide range of geochemical and geophysical data and methods....

The Coyote Mountain desert snail (Sonorelix harperi carrizoensis) was described in 1937 from 30 dry shells collected the previous year. We reviewed the literature and museum records and found two additional shell collections for this subspecies from the type locality one from 1958, and one from an adjacent mountain...

In unglaciated terrain, the imprint of past glacial periods is difficult to discern. The topographic signature of periglacial processes, such as solifluction lobes, may be erased or hidden by time and vegetation, and thus their import diminished. Belowground, periglacial weathering, particularly frost cracking, may have imparted a...

Insular species, particularly birds, experience high levels of speciation and endemism. Similarly, island birds experience extreme levels of extinction. Based on a 2012 taxonomic assessment, historically there were four reed-warbler species in the Mariana Islands, the Guam Reed-warbler Acrocephalus luscinia (Guam), the Nightingale Reed-warbler Acrocephalus hiwae (Saipan and Alamagan),...

In the San Joaquin Valley (SJV), California, about 10% of drinking water wells since 2010 had arsenic concentrations above the US maximum contaminant level of 10 μg/L. High concentrations of arsenic are often associated with high pH (greater than 7.8) or reduced geochemical conditions. Although most wells have low arsenic (<3 μg/L)...

Treated wastewater with high levels of ammonia has been injected, since March 1983 into the deep saline units of the Lower Floridan aquifer (LFA) from a treatment plant near the east coast of Miami-Dade County in southeastern Florida. Monitoring wells in the plant recorded ammonia concentrations above ambient levels at...

Avian keratin disorder (AKD), a disease of unknown etiology characterized by debilitating beak overgrowth, has increasingly affected wild bird populations since the 1990s. A novel picornavirus, poecivirus, is closely correlated with disease status in Black-capped Chickadees (Poecile atricapillus) in Alaska. However, our knowledge of the relationship between poecivirus and beak...

Mosquito-borne avian malaria Plasmodium relictum is a key limiting factor for endemic Hawaiian forest birds. In the past decade, populations of Kaua‘i’s endemic forest birds have been in a steep decline due to an increase in malaria transmission. To evaluate the use of available biopesticides for short-term mosquito control we...

Identifying and understanding status and trends in ecological indicators motivates continual monitoring over decades. Many programs rely on probability surveys and their companion design-based estimators for status assessments (e.g. Horvitz–Thompson). Design-based estimators do not easily extend to trend estimation nor situations with observation errors. Field-based monitoring efforts inevitably have...

Recurring slope lineae (RSL) are dark linear markings on Mars that regrow annually and likely originate from the flow of either liquid water or granular material. Following the great dust storm (or planet-encircling dust event, PEDE) of Mars year (MY) 34, Mars Reconnaissance Orbiter/High Resolution Imaging Science...

Collaborative monitoring over broad scales and levels of ecological organization can inform conservation efforts necessary to address the contemporary biodiversity crisis. An important challenge to collaborative monitoring is motivating local engagement with enough buy-in from stakeholders while providing adequate top-down direction for scientific rigor, quality control,...

The Hayward fault in California's San Francisco Bay area produces large earthquakes, with the last occurring in 1868. We examine how physics‐based dynamic rupture modeling can be used to numerically simulate large earthquakes on not only the Hayward fault, but also its connected companions to the north and south, the...

With aquifers around the world stressed by over-extraction, water managers are increasingly turning to managed aquifer recharge (MAR), directly replenishing groundwater resources through injection wells, recharge basins, or other approaches. While there has been progress in understanding the geological and infrastructure-related considerations to make MAR more effective,...

Coral reefs worldwide are experiencing rapid degradation in response to climate and land-use change, namely effects of warming sea-surface temperatures, contaminant runoff, and overfishing. Extensive coral bleaching caused by the steady rise of sea-surface temperatures is projected to increase, but our understanding and ability to predict where corals may be...

The recovery of large carnivore species from over‐exploitation can have socioecological effects; thus, reliable estimates of potential abundance and distribution represent a valuable tool for developing management objectives and recovery criteria. For sea otters (Enhydra lutris), as with many apex predators, equilibrium abundance is not constant across space but rather...

Natural disturbances are an important driver of population dynamics. Because it is difficult to observe wildlife during these events, our understanding of the strategies that species use to survive these disturbances is limited. On October 10, 2018, Hurricane Michael made landfall on Florida’s northwest coast. Using satellite and acoustic telemetry,...

Grazing management recommendations often sacrifice the intrinsic heterogeneity of grasslands by prescribing uniform grazing distributions through smaller pastures, increased stocking densities, and reduced grazing periods. The lack of patch-burn grazing in semi-arid landscapes of the western Great Plains in North America requires alternative grazing management strategies to create and maintain...

Reproduction is a key component of ecological resilience in forest ecosystems, so understanding how seed production is influenced by extreme drought is key to understanding forest recovery trajectories. If trees respond to mortality-inducing drought by preferentially allocating resources for reproduction, the...