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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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...
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....
Kittiwake diets and chick production signal a 2008 regime shift in the Northeast Pacific
Scott A. Hatch
2013, Marine Ecology Progress Series (477) 271-284
I examined ~2700 food samples collected from adult and nestling black-legged kittiwakes Rissa tridactyla from 1978 through 2011 on Middleton Island in the Gulf of Alaska. The kittiwake diet was composed chiefly of fish, but invertebrates were taken in appreciable quantities in April and May. Upon spring arrival at the...
Diet of the eastern mudminnow (Umbra pygmaea DeKay) from two geographically distinct populations within the North American native range
Frank M. Panek, Judith S. Weis
2013, Northeastern Naturalist (20) 37-48
Umbra pygmaea (Eastern Mudminnow) is a freshwater species common in Atlantic slope coastal lowlands from southern New York to northern Florida and is typical of slow-moving, mud-bottomed, and highly vegetated streams, swamps, and small ponds. We examined its seasonal food habits at the Great Swamp National Wildlife Refuge (NWR), NJ...
Development of MODFLOW-USG: an un-structured grid version of MODFLOW
Sorab Panday
2013, International Association of Hydrogeologists Newsletter (42) 4-5
MODFLOW was revolutionary when it was first unveiled by the USGS in 1988, and since then it has been the most widely used groundwater flow modeling program in the world. MODFLOW’s simulation capabilities have evolved substantially since its initial release and it has been an inspiration for more comprehensive analysis...
Historical rock falls in Yosemite National Park, California (1857-2011)
Greg M. Stock, Brian D. Collins, David J. Santaniello, Valerie L. Zimmer, Gerald F. Wieczorek, James B. Snyder
2013, Data Series 746
Inventories of rock falls and other types of landslides are valuable tools for improving understanding of these events. For example, detailed information on rock falls is critical for identifying mechanisms that trigger rock falls, for quantifying the susceptibility of different cliffs to rock falls, and for developing magnitude-frequency relations. Further,...
Methods and results of peak-flow frequency analyses for streamgages in and bordering Minnesota, through water year 2011
Erich W. Kessler, David L. Lorenz, Christopher A. Sanocki
2013, Scientific Investigations Report 2013-5110
Peak-flow frequency analyses were completed for 409 streamgages in and bordering Minnesota having at least 10 systematic peak flows through water year 2011. Selected annual exceedance probabilities were determined by fitting a log-Pearson type III probability distribution to the recorded annual peak flows. A detailed explanation of the methods that...
Kinetics of homogeneous and surface-catalyzed mercury(II) reduction by iron(II)
Aria Amirbahman, Douglas B. Kent, Gary P. Curtis, Mark C. Marvin-DiPasquale
2013, Environmental Science & Technology (47) 7204-7213
Production of elemental mercury, Hg(0), via Hg(II) reduction is an important pathway that should be considered when studying Hg fate in environment. We conducted a kinetic study of abiotic homogeneous and surface-catalyzed Hg(0) production by Fe(II) under dark anoxic conditions. Hg(0) production rate, from initial 50 pM Hg(II) concentration, increased...
Disinfection of three wading boot surfaces infested with New Zealand mudsnails
Kelly A. Stockton, Christine M. Moffitt
2013, North American Journal of Fisheries Management (33) 529-538
New Zealand mudsnails Potamopyrgus antipodarum (NZMS) have been introduced into many continents and are easily transported live while attached to wading and other field gear. We quantified the relative attachment by different life stages of NZMS to felt, neoprene, and rubber-soled boots exposed to two densities of NZMS in experimental...
Multi-temporal maps of the Montaguto earth flow in southern Italy from 1954 to 2010
Luigi Guerriero, Paola Revellino, Jeffrey A. Coe, Mariano Focareta, Gerardo Grelle, Vincenzo Albanese, Angelo Corazza, Francesco M. Guadagno
2013, Journal of Maps (9) 135-145
Historical movement of the Montaguto earth flow in southern Italy has periodically destroyed residences and farmland, and damaged the Italian National Road SS90 and the Benevento-Foggia National Railway. This paper provides maps from an investigation into the evolution of the Montaguto earth flow from 1954 to 2010. We used aerial...
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,...
