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Brimstone Basin, a remote area of intense hydrothermal alteration a few km east of the Yellowstone Caldera, is rarely studied and has long been considered to be a cold remnant of an ancient hydrothermal system. A field campaign in 2008 confirmed that gas emissions from the few small vents were...

Pacific walruses (Odobenus rosmarus divergens) occupying shelf waters of Pacific Arctic seas migrate during spring and summer from 3 breeding areas in the Bering Sea to form sexually segregated nonbreeding aggregations. We assessed genetic relationships among 2 putative breeding populations and 6 nonbreeding aggregations. Analyses of mitochondrial DNA (mtDNA) control...

In 2013, the U.S. Geological Survey (USGS) National Water-Quality Assessment Program (NAWQA) and USGS Columbia Environmental Research Center (CERC) will be collaborating with the U.S. Environmental Protection Agency (EPA) National Rivers and Streams Assessment (NRSA) to assess stream quality across the Midwestern United States. The sites selected for this study...

This assessment was conducted to fulfill the requirements of section 712 of the Energy Independence and Security Act (EISA) of 2007 and to improve understanding of carbon and greenhouse gas (GHG) fluxes in ecosystems of the Western United States. The assessment examined carbon storage, carbon fluxes, and other GHG fluxes...

Probabilities of arsenic occurrence in groundwater from bedrock aquifers at concentrations of 1, 5, and 10 micrograms per liter (µg/L) were estimated during 2011 using multivariate logistic regression. These estimates were developed for use by the New Hampshire Environmental Public Health Tracking Program. About 39 percent of New Hampshire bedrock...

Lake Maumelle, located in central Arkansas northwest of the cities of Little Rock and North Little Rock, is one of two principal drinking-water supplies for the Little Rock, and North Little Rock, Arkansas, metropolitan areas. Lake Maumelle and the Maumelle River (its primary tributary) are more pristine than most other...

Dry deposition of speciated mercury, i.e., gaseous oxidized mercury (GOM), particulate-bound mercury (PBM), and gaseous elemental mercury (GEM), was estimated for the year 2008–2009 at 19 monitoring locations in eastern and central North America. Dry deposition estimates were obtained by combining monitored two- to four-hourly speciated ambient concentrations with modeled...

We surveyed birds on grain and non-grain fields in the Tulare Basin of California treated post-harvest with two types of flooding that varied in duration and depth of water applied (Flooded-type fields [FLD]: 1 week; Irrigated-type fields [IRG]: <1-15 cm water for <1 week at a...

The U. S. Geological Survey, in cooperation with the U.S. Department of Energy, is mapping the distribution of basalt flows and sedimentary interbeds at the Idaho National Laboratory in three dimensions to provide data for refining numerical models of groundwater flow and contaminant transport in the eastern Snake River Plain...

As the world's largest distributed store of fresh water, ground water plays a central part in sustaining ecosystems and enabling human adaptation to climate variability and change. The strategic importance of ground water for global water and food security will probably intensify under climate change as more frequent and intense...

The U.S. Geological Survey has developed an open-standard data integration framework for working efficiently and effectively with large collections of climate and other geoscience data. A web interface accesses catalog datasets to find data services. Data resources can then be rendered for mapping and dataset metadata are derived directly from...

Riverine catostomids can show a wide range of interspecific variation in life-history characteristics. Understanding these differences is an important consideration in evaluating the sensitivity of these fishes to disturbance and in formulating effective conservation strategies, particularly when dealing with an assemblage consisting of multiple species within a watershed. We collected...

Northern high-latitude rivers transport large amounts of terrestrially derived dissolved organic matter (DOM) from boreal and arctic ecosystems to coastal areas and oceans. Current knowledge of the biodegradability of DOM in these rivers is limited, particularly for large rivers discharging to the Arctic Ocean. We conducted a seasonally comprehensive study...

Large rivers throughout the world have been modified by using dike structures to divert water flows to deepwater habitats to maintain navigation channels. These modifications have been implicated in the decline in habitat diversity and native fishes. However, dike structures have been modified in the Missouri River USA to increase...

Study Summary The influence of stream flow on salmon smolt emigration survival is a topic of widespread management interest. We collected smolt survival data to inform flow management decisions in the Yakima Basin. The Yakima River watershed drains the eastern slopes of the Cascade Mountain Range in central Washington State. The...

Interstitial water temperature within spawning habitats of salmonids may differ from surface-water temperature depending on intragravel flow paths, geomorphic setting, or presence of groundwater. Because survival and developmental timing of salmon are partly controlled by temperature, monitoring temperature within gravels used by spawning salmonids is required to adequately describe the...

Aquifer overexploitation could significantly impact crop production in the United States because 60% of irrigation relies on groundwater. Groundwater depletion in the irrigated High Plains and California Central Valley accounts for ∼50% of groundwater depletion in the United States since 1900. A newly developed High Plains recharge map shows that...

Alternative male phenotypes in salmonine fishes arise from individuals that mature as larger and older anadromous marine-migrants or as smaller and younger freshwater residents. To better understand the processes influencing the expression of these phenotypes we examined the influences of growth in length (fork length) and whole body lipid content...

As the only extant deepwater cisco in Lake Michigan, bloater is currently at record low levels of abundance.  Several mechanisms to regulate their recruitment have been proposed, including skewed sex ratios, predation on their larvae by adult alewife, and climatic factors during early life history stages, but none has...

The thermal output from the Yellowstone magma chamber can be estimated from the Cl flux in the major rivers in Yellowstone National Park; and by utilizing continuous discharge and electrical conductivity measurements the Cl flux can be calculated. The relationship between electrical conductivity and concentrations of Cl and other geothermal...

Characterization of vertebrate chemo-orientation strategies over long distances is difficult because it is often not feasible to conduct highly controlled hypothesis-based experiments in natural environments. To overcome the challenge, we couple in-stream behavioral observations of female sea lampreys (Petromyzon marinus) orienting to plumes of a synthesized mating pheromone, 7a,12a,24-trihydroxy-5a-cholan-3-one-24-sulfate (3kPZS),...

The migratory population of the King Rail (Rallus elegans) has declined dramatically during the past 50 years, emphasizing the need to document the distribution and status of this species to help guide conservation efforts. In an effort to guide King Rail breeding habitat protection and restoration, a landscape suitability index...

We compared Bythotrephes population demographics and dynamics to predator (planktivorous fish) and prey (small-bodied crustacean zooplankton) densities at a site sampled through the growing season in Lakes Michigan, Huron, and Erie. Although seasonal average densities of Bythotrephes were similar across lakes (222/m2 Erie, 247/m2 Huron, 162/m2 Michigan), temporal trends in...

Although global food production has been rising, the world sti ll faces a major food security challenge. Over one billion people are currently undernourished (Wheeler and Kay, 2010). By the 2050s, the human population is projected to grow to 9.1 billion. Over three-quarters of these people will be living in...

The Northern Rockies Ecoregion (Omernik, 1987; U.S. Environmental Protection Agency, 1997) covers approximately 162,746 km2 (63,200 mi2), primarily in Idaho but also including areas in western Montana and northeastern Washington (fig. 1). Canada forms the northern border of the ecoregion. To the west it is bordered by the Columbia Plateau...