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Two aeromagnetic surveys were flown to promote further understanding of the geology and structure in northwest Utah and adjacent parts of Nevada and Idaho by serving as a basis for geophysical interpretations and by supporting geological mapping, water and mineral resource investigations, and other topical studies. Although this area is...

A synthesis of Late Jurassic and Early Cretaceous collision-related metamorphic events in the Arctic Alaska–Chukotka microplate clarifies its likely movement history during opening of the Amerasian and Canada basins. Comprehensive tectonic reconstructions of basin opening have been problematic, in part, because of the large size of the microplate, uncertainties...

Natural resource professionals have frequently criticized universities for poorly preparing graduates to succeed in their jobs. We surveyed members of the American Fisheries Society to determine which job skills and knowledge of academic topics employers, students, and university faculty members deemed most important to early-career success of fisheries professionals. Respondents...

Health of humans, animals, plants, and ecosystems are intertwined. Disturbance tips the balance in favor of weedy species, vectors, and disease agents. Biodiversity is important to prevent imbalance in nature. However, more scholarship is needed, and there is still much more to study, understand, and manage than we currently know....

This chapter enumerates the steps required in designing and planning field studies on the ecology and conservation of reptiles, as these involve a high level of uncertainty and risk. To this end, the chapter differentiates between goals (descriptions of what one intends to accomplish) and objectives (the...

Surplus nitrogen (N) estimates, principal component analysis (PCA), and end-member mixing analysis (EMMA) were used in a multisite comparison contrasting the fate of N in diverse agricultural watersheds. We applied PCA-EMMA in 10 watersheds located in Indiana, Iowa, Maryland, Nebraska, Mississippi, and Washington ranging in size from 5 to 1254...

Invasion of North American waters by nonnative Dreissena polymorpha and D. rostriformis bugensishas resulted in declines of the Unionidae family of native North American mussels. Dreissenid mussels biofoul unionid mussels in large numbers and interfere with unionid movement, their acquisition of food, and the native mussels' ability to open and close their shells....

Corrosive groundwater, if untreated, can dissolve lead and other metals from pipes and other components in water distribution systems. Two indicators of potential corrosivity—the Langelier Saturation Index (LSI) and the Potential to Promote Galvanic Corrosion (PPGC)—were used to identify which areas in the United States might be more susceptible to...

The “Judas” technique is based on the idea that a radio-tagged individual can be used to “betray” conspecifics during the course of its routine social behavior. The Burmese python (Python bivittatus) is an invasive constrictor in southern Florida, and few methods are available for its control....

In western North America, where infestations of mountain pine beetles continue to ravage thousands of acres of forest lands, Landsat satellites bear witness to the onslaught in a way that neither humans nor most other satellites can see....

A wildfire’s devastation of forest and rangeland seldom ends when the last embers die. In the western United States, rain on a scorched mountainside can turn ash into mudslides. Debris flows unleashed by rainstorms can put nearby homes into harm’s way and send people scrambling for safety. The infrared capabilities...

Phosphorus data were collected from the Kent Park Lake watershed in Johnson County, Iowa, in 2014 and 2015 to obtain information to assist in the management of the water quality in the lake. Phosphorus concentrations were measured for sediment from several ponds in the watershed and sediment deposited in the...

Introduction The Hells Canyon Complex (HCC) is a hydroelectric project built and operated by the Idaho Power Company (IPC) that consists of three dams on the Snake River along the Oregon and Idaho border (fig. 1). The dams have resulted in the creation of Brownlee, Oxbow, and Hells Canyon Reservoirs, which have a combined storage capacity...

This study describes channel changes following completion of the Provo River Restoration Project (PRRP), the largest stream restoration project in Utah and one of the largest projects in the United States in which a gravel-bed river was fully reconstructed. We summarize project objectives and the design process, and we analyze...

Summary In response to the recent removal of international sanctions on Iran, including the lifting of “secondary” sanctions by the United States on investment into and trade with Iran, the U.S. Geological Survey National Minerals Information Center compiled and analyzed available information on the current state of Iran’s nonfuel minerals industry....

Suspended-sediment characteristics can be computed using acoustic indices derived from acoustic Doppler velocity meter (ADVM) backscatter data. The sediment acoustic index method applied in these types of studies can be used to more accurately and cost-effectively provide time-series estimates of suspended-sediment concentration and load, which is essential for informed solutions...

Livestock fences have been hypothesized to significantly contribute to mortality of lesser prairie-chickens (Tympanuchus pallidicinctus); however, quantification of mortality due to fence collisions is lacking across their current distribution. Variation in fence density, landscape composition and configuration, and land use could influence collision risk of lesser prairie-chickens. We monitored fences...

Priodontes maximus (Kerr, 1792), called the giant armadillo, is monotypic and by far the largest extant armadillo. Average adult weight is about 30kg (in captivity, as high as 80kg). Its carapace extends about halfway down its sides, making it impossible to curl up tightly. It is...

Fish represent high quality protein and nutrient sources, but Hg contamination is ubiquitous in aquatic ecosystems and can pose health risks to fish and their consumers. Potential health risks posed to fish and humans by Hg contamination in fish were assessed in western Canada and the United States. A large...

Thyroid hormone reportedly induces masculinization of genetic females and goitrogen treatment delays testicular differentiation (ovary-to-testis transformation) in genetic males of Zebrafish. This study explored potential molecular mechanisms of these phenomena. Zebrafish were treated with thyroxine (T4, 2 nM), goitrogen [methimazole (MZ), 0.15 mM], MZ (0.15 mM) and T4 (2 nM) (rescue treatment), or reconstituted...

Resource flows from adjacent ecosystems are critical in maintaining structure and function of freshwater food webs. Migrating sea lamprey (Petromyzon marinus) deliver a pulsed marine-derived nutrient subsidy to rivers in spring when the metabolic demand of producers and consumers are increasing. However, the spatial and temporal dynamics of these nutrient...

Many anthropogenic disturbances have contributed to the decline of Pacific lampreys (Entosphenus tridentatus), but potential negative effects of contaminants on lampreys are unclear. Lamprey ammocoetes are the only detritivorous fish in the lower Willamette River, Oregon, USA, and have been observed in Portland Harbor sediments. Their long benthic larval stage...

High-resolution seismic-reflection and refraction images of the 1906 surface rupture zone of the San Andreas Fault near Woodside, California reveal evidence for one or more additional near-surface (within about 3 meters [m] depth) fault strands within about 25 m of the 1906 surface rupture. The 1906 surface rupture above the...

The crater lake of Kawah Ijen volcano, East Java, Indonesia, has displayed large and rapid changes in temperature at point locations during periods of unrest, but measurement techniques employed to-date have not resolved how the lake’s thermal regime has evolved over both space and time. We applied a novel approach...

Using a geology-based assessment methodology, the U.S. Geological Survey estimated undiscovered, technically recoverable mean resource of 44.5 trillion cubic feet of shale gas in the Karoo Province of South Africa and Lesotho, Africa....