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The African Jewelfish, Hemichromis letourneuxi, is an invasive, predatory cichlid fish introduced at least once to Florida. Its native range is in northern Africa. First encountered in Miami in the 1960s, it has since been found west and north within the State of Florida. It thrives in a wide range of...

In the mid-1990s, the population size of Florida panthers became so small that many individuals manifested traits associated with inbreeding depression (e.g., heart defects, cryptorchidism, high pathogen-parasite load). To mitigate these effects, pumas from Texas were introduced into South Florida to augment genetic variation in Florida panthers. In this study,...

Core IdeasOxbows reduce nitrate export from agricultural fields to adjacent rivers and streams.Oxbows are important habitat for wildlife, including the endangered Topeka shiner.Oxbows have largely disappeared from midwestern landscapes modified for agriculture.Restoring multipurpose oxbows provides multiple benefits in the agricultural Midwest.Nutrient export from the agricultural...

The newly constructed tallest building designed in conformance with performance-based design procedure in San Francisco, California is a 61-story building equipped with an accelerometric array that recorded the January 4, 2018 M4.4 Berkeley earthquake. The building is designed with concrete core shear walls and perimeter gravity steel...

Extreme precipitation events are one of the most consequential components of climate change for society. The El Niño-Southern Oscillation (ENSO) is the dominant mode of precipitation variability in the tropics and causes severe flooding and drought in many socioeconomically vulnerable regions. It remains unclear how tropical rainfall extremes and ENSO...

Land clearing, river impoundments, and other human modifications to the upland landscape and within estuarine systems can drive coastal change at local to regional scales. However, as compared with mid-latitude coasts, the impacts of human modifications along sediment-starved formerly glaciated coastal landscapes are relatively understudied. To address this...

The Colorado Department of Public Health and Environment (CDPHE), the National Park Service (NPS), and the U.S. Environmental Protection Agency (EPA) issued the Nitrogen Deposition Reduction Plan (NDRP) in 2007 to address the effects and trends of nitrogen deposition at Rocky Mountain National Park (RMNP). The agencies chose a glidepath...

Recent widespread seismicity in Oklahoma is attributed to the reactivation of pre-existing, critically stressed and seismically unstable faults due to decades of wastewater injection. However, the structure and properties of the reactivated faults remain concealed by the sedimentary cover. Here, we explore the major ingredients needed to induce earthquakes in...

Structured decision making is a systematic, transparent process for improving the quality of complex decisions by identifying measurable management objectives and feasible management actions; predicting the potential consequences of management actions relative to the stated objectives; and selecting a course of action that maximizes the total benefit achieved and balances...

The U.S. Geological Survey Columbia Environmental Research Center performs research to solve challenging environmental problems related to contaminants and habitat alterations in aquatic and terrestrial ecosystems. The research is interdisciplinary and pursued through partnerships within the U.S. Geological Survey and with national, international, state, and local agencies; nongovernmental organizations; and...

In 2016, the U.S. Geological Survey deployed more than 1,800 vertical-component nodal seismometers in Grant County, Oklahoma to study induced seismic activity associated with production of the Mississippi Limestone Play. The LArge-n Seismic Survey in Oklahoma (LASSO) array operated for approximately one month, covering a 25-km-by-32-km region with a nominal...

In the Madrean Sky Islands of western North America, a mixture of public and private land ownership and tenure creates a complex situation for collaborative efforts in conservation. In this case study, we describe the current ownership and management structures in the US-Mexico borderlands where social, political, and economic conditions...

A primary goal of volcanology is forecasting hazardous eruptive activity. Despite much progress over the last century, however, volcanoes still erupt with no detected precursors, lives and livelihoods are lost to eruptive activity, and forecasting the onsets of eruptions remains fraught with uncertainty. Long‐term forecasts are generally...

The Sierra Madre fault system accommodates contraction within a large restraining bend area of the San Andreas fault along the northern margin of the Los Angeles metropolitan area in Southern California. Reverse slip along this fault system during earthquakes controls growth of the San Gabriel Mountains and poses a significant...

We employ strong motion seismograms and static offsets from the Global Positioning System, Interferometric Synthetic Aperture Radar, and other measurements in order to derive a coseismic slip and afterslip model of the M6.0 24 August 2014 South Napa earthquake. This earthquake ruptured an ∼13‐km‐long portion of...

A previously published field-experimental investigation showed that injection of nitrate in anoxic groundwater that contained aqueous and sediment-bound Fe(II) diminished concentrations of As(V) and As(III) to below drinking-water limits. In the current study, reactive transport modeling confirmed that the observed attenuation was consistent with oxidation of Fe(II) by nitrate, leading...

Functions of inland, freshwater depressional wetlands of the Great Plains are driven by natural disturbance in the form of fluctuating water levels or shifts between wet and dry ecological states. The geographically isolated prairie potholes and playas form broad-scale systems or networks that support biodiversity and provide ecological goods and...

Lake charr Salvelinus namaycush are endemic to the formerly glaciated regions of North America and spawn primarily in lakes, unlike most other Salmoninae. Spawning habitats for lake charr are thought to be characterized by relatively large substrate particle sizes which provide sufficient interstitial spaces for egg incubation, but little is...

The Sahara in North Africa and the Gobi and Taklamakan deserts in Asia are the primary sources of mobilized dust in the atmosphere, with regional or global airborne transport estimated at 2 to 5 billion tonnes per year. Annual Asian dust plumes take about 7 to 10 d to cross the...

Invasive annual grasses are of concern in many areas of the Western United States because they tolerate resource variability and have high reproductive capacity, with propagules that are readily dispersed in disturbed areas like those created and maintained for energy development. Early-season invasive grasses “green up” earlier than the most...

The Colville Confederated Tribes (CCT) Chief Joseph Hatchery (CJH) is the fourth hatchery obligated under the Grand Coulee Dam/Dry Falls project, originating in the 1940s. Leavenworth, Entiat, and Winthrop National Fish Hatcheries were built and operated as mitigation for salmon blockage at Grand Coulee Dam, but the fourth hatchery was...

In view of the U.S. Army’s historical reliance and plans to increase demands on groundwater to supply its operations at Fort Irwin National Training Center (NTC), California, coupled with the continuing water-level declines in some developed groundwater basins as a result of pumping, the U.S. Geological Survey (USGS), in cooperation...

Globally, aquatic biodiversity is imperiled at an increasing rate, especially in diversity hotspots such as the southeastern USA. The spotfin chub Erimonax monachus is a federally threatened minnow with a disjunct distribution resulting from numerous impoundments on the Tennessee River and its tributaries in the heart of the southeastern USA. Recovery actions...

Within the field of ecology, disturbance can be defined as a physical force, agent, or process, either abiotic or biotic, causing a perturbation or stress, to an ecological component or system, relative to a specified reference state and/or system. Disturbance drive ecosystems, and our understanding of how disturbances interact with...

Noninvasive fecal sampling combined with genetic analysis is a powerful technique allowing the study of elusive or otherwise difficult to monitor species without the need for direct contact. While this method is widely used in birds and mammals, it has never been successfully applied on a large scale in reptiles....