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Page 1474, results 36826 - 36850

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Estimating suitable environments for invasive plant species across large landscapes: a remote sensing strategy using Landsat 7 ETM+
Kendal E. Young, Laurie B. Abbott, Colleen A. Caldwell, T. Scott Schrader
2013, International Journal of Biodiversity and Conservation (5) 122-134
The key to reducing ecological and economic damage caused by invasive plant species is to locate and eradicate new invasions before they threaten native biodiversity and ecological processes. We used Landsat Enhanced Thematic Mapper Plus imagery to estimate suitable environments for four invasive plants in Big Bend National Park, southwest...
First documented occurrences of the shortnose sturgeon (Acipenser brevirostrum) in the Saco River, Maine, USA
C.E. Little, M. Kieffer, G. Wippelhauser, G. Zydlewski, M. Kinnison, L. A. Whitefleet-Smith, J.A. Sulikowski
2013, Journal of Applied Ichthyology (29) 709-712
During sampling efforts to study the more abundant Atlantic sturgeon, Acipenser oxyrinchus oxyrinchus, between May of 2009 and November of 2011, four shortnose sturgeon were captured in gill nets near the mouth of the Saco River, Maine. Two of these individuals were tagged with acoustic transmitters to monitor their movement...
Environmental DNA as a new method for early detection of New Zealand mudsnails (Potamopyrgus antipodarum)
Caren S. Goldberg, Adam Sepulveda, Andrew Ray, Jeremy A. Baumgardt, Lisette P. Waits
2013, Freshwater Science (32) 792-800
Early detection of aquatic invasive species is a critical task for management of aquatic ecosystems. This task is hindered by the difficulty and cost of surveying aquatic systems thoroughly. The New Zealand mudsnail (Potamopyrgus antipodarum) is a small, invasive parthenogenic mollusk that can reach very high population densities and severely...
Characterization of major lithologic units underlying the lower American River using water-borne continuous resistivity profiling, Sacramento, California, June 2008
Lyndsay B. Ball, Andrew Teeple
2013, Open-File Report 2013-1050
The levee system of the lower American River in Sacramento, California, is situated above a mixed lithology of alluvial deposits that range from clay to gravel. In addition, sand deposits related to hydraulic mining activities underlie the floodplain and are preferentially prone to scour during high-flow events. In contrast, sections...
Effects of depletion sampling by standard three-pass pulsed DC electrofishing on blood chemistry parameters of fishes from Appalachian streams
Christine L. Densmore, Frank M. Panek
2013, North American Journal of Fisheries Management (33) 298-306
Adverse effects on fishes captured by electrofishing techniques have long been recognized, although the extent of associated physical injury and behavioral alterations are highly variable and dependent on a number of factors. We examined the effects of three-pass pulsed DC (PDC) electrofishing on two salmonid species (Rainbow Trout Oncorhynchus mykiss...
Internal nutrient sources and nutrient distributions in Alviso Pond A3W, California
Brent R. Topping, James S. Kuwabara, Krista K. Garrett, John Y. Takekawa, Francis Parcheso, Sara Piotter, Iris Clearwater, Gregory Shellenbarger
2013, Open-File Report 2013-1128
Within the Alviso Salt Pond complex, California, currently undergoing avian-habitat restoration, pore-water profilers (U.S. Patent 8,051,727 B1) were deployed in triplicate at two contrasting sites in Pond A3W (“Inlet”, near the inflow, and “Deep”, near the middle of the pond; figs. 1 and 2; table 1, note that tables in...
Exploration Review
D.R. Wilburn, K.A. Stanley
2013, Mining Engineering (65) 32-52
This summary of international mineral exploration activities for 2012 draws upon information from industry sources, published literature and U.S. Geological Survey (USGS) specialists. The summary provides data on exploration budgets by region and mineral commodity, identifies significant mineral discoveries and areas of mineral exploration, discusses government programs affecting the mineral...
Streamflow and water-quality conditions including geologic sources and processes affecting selenium loading in the Toll Gate Creek watershed, Aurora, Arapahoe County, Colorado, 2007
Suzanne S. Paschke, Robert L. Runkel, Katherine Walton-Day, Briant A. Kimball, Keelin R. Schaffrath
2013, Scientific Investigations Report 2012-5280
Toll Gate Creek is a perennial stream draining a suburban area in Aurora, Colorado, where selenium concentrations have consistently exceeded the State of Colorado aquatic-life standard for selenium of 4.6 micrograms per liter since the early 2000s. In cooperation with the City of Aurora, Colorado, Utilities Department, a synoptic water-quality...
Mining Review
National Minerals Information Center
2013, Mining Engineering (65) 22-31
In 2012, the estimated value of mineral production increased in the United States for the third consecutive year. Production and prices increased for most industrial mineral commodities mined in the United States. While production for most metals remained relatively unchanged, with the notable exception of gold, the prices for most...
Landscape factors and hydrology influence mercury concentrations in wading birds breeding in the Florida Everglades, USA
Garth Herring, Collin A. Eagles-Smith, Joshua T. Ackerman, Dale E. Gawlik, James M. Beerens
2013, Science of the Total Environment (458-460) 637-646
The hydrology of wetland ecosystems is a key driver of both mercury (Hg) methylation and waterbird foraging ecology, and hence may play a fundamental role in waterbird exposure and risk to Hg contamination. However, few studies have investigated hydrological factors that influence waterbird Hg exposure. We examined how several landscape-level...
Endozoochory of seeds and invertebrates by migratory waterbirds in Oklahoma, USA
Andy J. Green, Dagmar Frisch, Thomas C. Michot, Larry K. Allain, Wylie C. Barrow
2013, Limnetica (32) 39-46
Given their abundance and migratory behavior, waterbirds have major potential for dispersing plants and invertebrates within North America, yet their role as vectors remains poorly understood. We investigated the numbers and types of invertebrates and seeds within freshly collected faecal samples (n = 22) of migratory dabbling ducks and shorebirds...
Breeding biology of an afrotropical forest understory bird community in northeastern Tanzania
Victor J. Mkongewa, William D. Newmark, Thomas R. Stanley
2013, Wilson Journal of Ornithology (125) 260-267
Many aspects of the breeding biology of Afrotropical forest birds are poorly known. Here we provide a description based on the monitoring of 1461 active nests over eight breeding seasons about one or more aspects of the breeding biology for 28 coexisting understory bird species on the Amani Plateau in...
Importance of terrestrial arthropods as subsidies in lowland Neotropical rain forest stream ecosystems
Gaston E. Small, Pedro J. Torres, Lauren M. Schwizer, John H. Duff, Catherine M. Pringle
2013, Biotropica (45) 80-87
The importance of terrestrial arthropods has been documented in temperate stream ecosystems, but little is known about the magnitude of these inputs in tropical streams. Terrestrial arthropods falling from the canopy of tropical forests may be an important subsidy to tropical stream food webs and could also represent an important...
Emergence flux declines disproportionately to larval density along a stream metals gradient
Travis S. Schmidt, Johanna M. Kraus, David M. Walters, Richard B. Wanty
2013, Environmental Science & Technology (47) 8784-8792
Effects of contaminants on adult aquatic insect emergence are less well understood than effects on insect larvae. We compared responses of larval density and adult emergence along a metal contamination gradient. Nonlinear threshold responses were generally observed for larvae and emergers. Larval densities decreased significantly at low metal concentrations but...
Efficacy of calf:cow ratios for estimating calf production of arctic caribou
R.D. Cameron, B. Griffith, L.S. Parrett, R.G. White
2013, Rangifer (33) 27-34
Caribou (Rangifer tarandus granti) calf:cow ratios (CCR) computed from composition counts obtained on arctic calving grounds are biased estimators of net calf production (NCP, the product of parturition rate and early calf survival) for sexually-mature females. Sexually-immature 2-year-old females, which are indistinguishable from sexually-mature females without calves, are included in...
Linking phenology and biomass productivity in South Dakota mixed-grass prairie
Matthew Rigge, Alexander Smart, Bruce Wylie, Tagir Gilmanov, Patricia Johnson
2013, Rangeland Ecology and Management (66) 579-587
Assessing the health of rangeland ecosystems based solely on annual biomass production does not fully describe plant community condition; the phenology of production can provide inferences on species composition, successional stage, and grazing impacts. We evaluate the productivity and phenology of western South Dakota mixed-grass prairie using 2000 to 2008...
Using structured decision making to manage disease risk for Montana wildlife
Michael S. Mitchell, Justin A. Gude, Neil J. Anderson, Jennifer M. Ramsey, Michael J. Thompson, Mark G. Sullivan, Victoria L. Edwards, Claire N. Gower, Jean Fitts Cochrane, Elise R. Irwin, Terry Walshe
2013, Wildlife Society Bulletin (37) 107-114
We used structured decision-making to develop a 2-part framework to assist managers in the proactive management of disease outbreaks in Montana, USA. The first part of the framework is a model to estimate the probability of disease outbreak given field observations available to managers. The second part of the framework...
Lake whitefish diet, condition, and energy density in Lake Champlain and the lower four Great Lakes following dreissenid invasions
Seth J. Herbst, J. Ellen Marsden, Brian F. Lantry
2013, Transactions of the American Fisheries Society (142) 388-398
Lake Whitefish Coregonus clupeaformis support some of the most valuable commercial freshwater fisheries in North America. Recent growth and condition decreases in Lake Whitefish populations in the Great Lakes have been attributed to the invasion of the dreissenid mussels, zebra mussels Dreissena polymorpha and quagga mussels D. bugensis, and the...
A model for evaluating effects of climate, water availability, and water management on wetland impoundments--a case study on Bowdoin, Long Lake, and Sand Lake National Wildlife Refuges
Brian A. Tangen, Robert A. Gleason, John F. Stamm
2013, Scientific Investigations Report 2013-5114
Many wetland impoundments managed by the U.S. Fish and Wildlife Service (USFWS) National Wildlife Refuge System throughout the northern Great Plains rely on rivers as a primary water source. A large number of these impoundments currently are being stressed from changes in water supplies and quality, and these problems are...
Chesapeake Bay hypoxic volume forecasts and results: June 18, 2013
Donald Scavia, Mary Anne Evans
2013, Report
The 2013 Forecast - Given the average Jan-May 2013 total nitrogen load of 162,028 kg/day, this summer’s hypoxia volume forecast is 6.1 km3, slightly smaller than average size for the period of record and almost the same as 2012....
Laurentian origin for the North Slope of Alaska: Implications for the tectonic evolution of the Arctic
J. V. Strauss, F. A. Macdonald, J. F. Taylor, John E. Repetski, W. C. McClelland
2013, Lithosphere (5) 477-482
The composite Arctic Alaska–Chukotka terrane plays a central role in tectonic reconstructions of the Arctic. An exotic, non-Laurentian origin of Arctic Alaska–Chukotka has been proposed based on paleobiogeographic faunal affinities and various geochronological constraints from the southwestern portions of the terrane. Here, we report early Paleozoic trilobite and conodont taxa...
Dynamic deformation of Seguam Island, Alaska, 1992--2008, from multi-interferogram InSAR processing
Chang-Wook Lee, Zhong Lu, Joong-Sun Won, Hyung-Sup Jung, Daniel Dzurisin
2013, Journal of Volcanology and Geothermal Research (260) 43-51
We generated a time-series of ERS-1/2 and ENVISAT interferometric synthetic aperture radar (InSAR) images to study ground surface deformation at Seguam Island from 1992 to 2008. We used the small baseline subset (SBAS) technique to reduce artifacts associated with baseline uncertainties and atmospheric delay anomalies, and processed images from two...
Baseline groundwater quality from 20 domestic wells in Sullivan County, Pennsylvania, 2012
Ronald A. Sloto
2013, Scientific Investigations Report 2013-5085
Water samples were collected from 20 domestic wells during August and September 2012 and analyzed for 47 constituents and properties, including nutrients, major ions, metals and trace elements, radioactivity, and dissolved gases, including methane and radon-222. This study, done in cooperation with the Pennsylvania Department of Conservation and Natural Resources, Bureau...
Hydraulic and water-quality data collection for the investigation of Great Lakes tributaries for Asian carp spawning and egg-transport suitability
Elizabeth A. Murphy, P. Ryan Jackson
2013, Scientific Investigations Report 2013-5106
If the invasive Asian carps (bighead carp Hypophthalmichthys nobilis and silver carp Hypophthalmichthys molitrix) migrate to the Great Lakes, in spite of the efforts to stop their advancement, these species will require the fast-flowing water of the Great Lakes tributaries for spawning and recruitment in order to establish a growing population. Two Lake...
Landscape consequences of natural gas extraction in Somerset and Westmoreland Counties, Pennsylvania,2004--2010
L.E. Milheim, E.T. Slonecker, C.M. Roig-Silva, A.R. Malizia
2013, Open-File Report 2013-1126
Increased demands for cleaner burning energy, coupled with the relatively recent technological advances in accessing unconventional hydrocarbon-rich geologic formations, have led to an intense effort to find and extract natural gas from various underground sources around the country. One of these sources, the Marcellus Shale, located in the Allegheny Plateau,...