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Page 10, results 226 - 250

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Sensitivity analysis of lake mass balance in discontinuous permafrost: the example of disappearing Twelvemile Lake, Yukon Flats, Alaska (USA)
S.M. Jepsen, C.I. Voss, Michelle Ann Walvoord, J.R. Rose, B. J. Minsley, B. D. Smith
2013, Hydrogeology Journal (21) 185-200
Many lakes in northern high latitudes have undergone substantial changes in surface area over the last four decades, possibly as a result of climate warming. In the discontinuous permafrost of Yukon Flats, interior Alaska (USA), these changes have been non-uniform across adjacent watersheds, suggesting local controls on lake water budgets....
The IUGS/IAGC Task Group on Global Geochemical Baselines
David B. Smith, Xueqiu Wang, Shaun Reeder, Alecos Demetriades
2012, Earth Science Frontiers (19) 1-6
The Task Group on Global Geochemical Baselines, operating under the auspices of both the International Union of Geological Sciences (IUGS) and the International Association of Geochemistry (IAGC), has the long-term goal of establishing a global geochemical database to document the concentration and distribution of chemical elements in the Earth’s surface...
History and progress of the North American Soil Geochemical Landscapes Project, 2001-2010
David B. Smith, William F. Cannon, Laurel G. Woodruff, Francisco Moreira Rivera, Andrew N. Rencz, Robert G. Garrett
2012, Earth Science Frontiers (19) 19-32
In 2007, the U.S. Geological Survey, the Geological Survey of Canada, and the Mexican Geological Survey initiated a low-density (1 site per 1600 km2, 13323 sites) geochemical and mineralogical survey of North American soils (North American Soil Geochemical Landscapes Project). Sampling and analytical protocols were developed at a series of...
Shale Gas Development and Brook Trout: Scaling Best Management Practices to Anticipate Cumulative Effects
David Smith, Craig D. Snyder, Nathaniel P. Hitt, John A. Young, Stephen P. Faulkner
2012, Environmental Practice (14) 366-381
Shale gas development may involve trade-offs between energy development and benefits provided by natural ecosystems. However, current best management practices (BMPs) focus on mitigating localized ecological degradation. We review evidence for cumulative effects of natural gas development on brook trout (Salvelinus fontinalis) and conclude that BMPs should account for potential...
Passage probabilities of juvenile Chinook salmon through the powerhouse and regulating outlet at Cougar Dam, Oregon, 2011
John W. Beeman, Amy C. Hansen, Scott D. Evans, Philip V. Haner, Hal C. Hansel, Collin D. Smith
2012, Open-File Report 2012-1250
Cougar Dam near Springfield, Oregon, is one of several federally owned and operated flood-control projects within the Willamette Valley of western Oregon that were determined by the National Oceanic and Atmospheric Administration’s National Marine Fisheries Service in 2008 to impact the long-term viability of several salmonid stocks. In response to...
A novel antibody-based biomarker for chronic algal toxin exposure and sub-acute neurotoxicity
Kathi A. Lefebvre, Elizabeth R. Frame, Frances Gulland, John D. Hansen, Preston S. Kendrick, Richard P. Beyer, Theo K. Bammler, Frederico M. Farin, Emma M. Hiolski, Donald R. Smith, David J. Marcinek
2012, PLoS ONE (7) e36213
The neurotoxic amino acid, domoic acid (DA), is naturally produced by marine phytoplankton and presents a significant threat to the health of marine mammals, seabirds and humans via transfer of the toxin through the foodweb. In humans, acute exposure causes a neurotoxic illness known as amnesic shellfish poisoning characterized by...
A multi-metric assessment of environmental contaminant exposure and effects in an urbanized reach of the Charles River near Watertown, Massachusetts
Stephen B. Smith, Patrick J. Anderson, Paul C. Baumann, Lawrence R. DeWeese, Steven L. Goodbred, James J. Coyle, David S. Smith
2012, Open-File Report 2012-1195
The Charles River Project provided an opportunity to simultaneously deploy a combination of biomonitoring techniques routinely used by the U.S. Geological Survey National Water Quality Assessment Program, the Biomonitoring of Environmental Status and Trends Project, and the Contaminant Biology Program at an urban site suspected to be contaminated with polycyclic...
Free tropospheric transport of microorganisms from Asia to North America
D. Smith, Dan Jaffe, Michele Birmele, Dale W. Griffin, Andrew Schuerger, J. Hee, Michael Roberts
2012, Microbial Ecology (64) 973-985
Microorganisms are abundant in the troposphere and can be transported vast distances on prevailing winds. This study measures the abundance and diversity of airborne bacteria and fungi sampled at the Mt. Bachelor Observatory (located 2.7 km above sea level in North America) where incoming free tropospheric air routinely arrives from...
Shifting species interactions in terrestrial dryland ecosystems under altered water availability and climate change
Kevin E. McCluney, Jayne Belnap, Scott L. Collins, Angélica L. González, Elizabeth M. Hagen, J. Nathaniel Holland, Burt P. Kotler, Fernando T. Maestre, Stanley D. Smith, Blair O. Wolf
2012, Biological Reviews (87) 563-582
Species interactions play key roles in linking the responses of populations, communities, and ecosystems to environmental change. For instance, species interactions are an important determinant of the complexity of changes in trophic biomass with variation in resources. Water resources are a major driver of terrestrial ecology and climate change is...
Estimating tag loss of the Atlantic Horseshoe crab, Limulus polyphemus, using a multi-state model
Catherine Alyssa Butler, Conor P. McGowan, J. Barry Grand, David Smith
2012, Conference Paper
The Atlantic Horseshoe crab, Limulus polyphemus, is a valuable resource along the Mid-Atlantic coast which has, in recent years, experienced new management paradigms due to increased concern about this species role in the environment. While current management actions are underway, many acknowledge the need for improved and updated parameter estimates...
Dawn at Vesta: testing the protoplanetary paradigm
C.T. Russell, C.A. Raymond, A. Coradini, H.Y. McSween, M.T. Zuber, A. Nathues, Maria-Cristina DeSanctis, R. Jaumann, A.S. Konopliv, F. Preusker, S.W. Asmar, R.S. Park, R. Gaskell, H.U. Keller, S. Mottola, T. Roatsch, J.E.C. Scully, D.E. Smith, P. Tricarico, M.J. Toplis, U.R. Christensen, W. C. Feldman, D. J. Lawrence, T.J. McCoy, T.H. Prettyman, R.C. Reedy, M.E. Sykes, T.N. Titus
2012, Science (336) 684-686
The Dawn spacecraft targeted 4 Vesta, believed to be a remnant intact protoplanet from the earliest epoch of solar system formation, based on analyses of howardite-eucrite-diogenite (HED) meteorites that indicate a differentiated parent body. Dawn observations reveal a giant basin at Vesta's south pole, whose excavation was sufficient to produce...
Archive eggs: a research and management tool for avian conservation breeding
Des H.V. Smith, Axel Moehrenschlager, Nancy Christensen, Dwight Knapik, Keith Gibson, Sarah J. Converse
2012, Wildlife Society Bulletin (36) 342-349
Worldwide, approximately 168 bird species are captive-bred for reintroduction into the wild. Programs tend to be initiated for species with a high level of endangerment. Depressed hatching success can be a problem for such programs and has been linked to artificial incubation. The need for artificial incubation is driven by...
Interim results from a study of the behavior of juvenile Chinook salmon at Cougar Reservoir and Dam, Oregon, March--August 2011
John W. Beeman, Hal C. Hansel, Amy C. Hansen, Philip V. Haner, Jamie M. Sprando, Collin D. Smith, Scott D. Evans
2012, Open-File Report 2012-1106
The movements and dam passage of yearling juvenile Chinook salmon implanted with acoustic transmitters and passive integrated transponder tags were studied at Cougar Reservoir and Dam, near Springfield, Oregon. A total of 411 hatchery fish and 26 wild fish were tagged and released between March 7 and May 21, 2011....
Use of real-time PCR to detect canine parvovirus in feces of free-ranging wolves
L. David Mech, Emily S. Almberg, Douglas Smith, Sagar Goyal, Randall S. Singer
2012, Journal of Wildlife Diseases (48) 473-476
Using real-time PCR, we tested 15 wolf (Canis lupus) feces from the Superior National Forest (SNF), Minnesota, USA, and 191 from Yellowstone National Park (YNP), USA, collected during summer and 13 during winter for canine parvovirus (CPV)-2 DNA. We also tested 20 dog feces for CPV-2 DNA. The PCR assay...
Characterization of nutrients and fecal indicator bacteria at a concentrated swine feeding operation in Wake County, North Carolina, 2009-2011
Stephen L. Harden, Shane W. Rogers, Michael A. Jahne, Carrie E. Shaffer, Douglas G. Smith
2012, Open-File Report 2012-1047
Hydrologic and water-quality data were collected during October 2009–January 2011 to characterize nutrient and bacteria concentrations in stormwater runoff from agricultural fields that receive wastewater originating at a swine facility at North Carolina State University's Lake Wheeler Road Field Laboratory (LWRFL) in Wake County, North Carolina. The swine facility consists...
Nonlinear effects of group size on the success of wolves hunting elk
Daniel R. MacNulty, Douglas W. Smith, L. David Mech, John A. Vucetich, Craig Packer
2012, Behavioral Ecology (23) 75-82
Despite the popular view that social predators live in groups because group hunting facilitates prey capture, the apparent tendency for hunting success to peak at small group sizes suggests that the formation of large groups is unrelated to prey capture. Few empirical studies, however, have tested for nonlinear relationships between...
Biosolids, crop, and groundwater data for a biosolids-application area near Deer Trail, Colorado, 2009 and 2010
Tracy J.B. Yager, David B. Smith, James G. Crock
2012, Data Series 664
During 2009 and 2010, the U.S. Geological Survey monitored the chemical composition of biosolids, crops, and groundwater related to biosolids applications near Deer Trail, Colorado, in cooperation with the Metro Wastewater Reclamation District. This monitoring effort was a continuation of the monitoring program begun in 1999 in cooperation with the...
Experimental and environmental factors affect spurious detection of ecological thresholds
Jonathan P. Daily, Nathaniel P. Hitt, David Smith, Craig D. Snyder
2012, Ecology (93) 17-23
Threshold detection methods are increasingly popular for assessing nonlinear responses to environmental change, but their statistical performance remains poorly understood. We simulated linear change in stream benthic macroinvertebrate communities and evaluated the performance of commonly used threshold detection methods based on model fitting (piecewise quantile regression [PQR]), data partitioning (nonparametric...
Available benthic habitat type may influence predation risk in larval lampreys
Dustin M. Smith, Stuart A. Welsh, Philip J. Turk
2012, Ecology of Freshwater Fish (21) 160-163
Population declines of lamprey species have largely been attributed to habitat degradation, yet there still remain many unanswered questions about the relationships between lampreys and their habitats (Torgensen & Close 2004; Smith et al. 2011). One...
Airborne electromagnetic imaging of discontinuous permafrost
B. J. Minsley, J.D. Abraham, B. D. Smith, J. C. Cannia, C.I. Voss, M.T. Jorgenson, Michelle Ann Walvoord, B.K. Wylie, L. Anderson, L.B. Ball, M. Deszcz-Pan, T.P. Wellman, T. A. Ager
2012, Geophysical Research Letters (39) 1-8
The evolution of permafrost in cold regions is inextricably connected to hydrogeologic processes, climate, and ecosystems. Permafrost thawing has been linked to changes in wetland and lake areas, alteration of the groundwater contribution to streamflow, carbon release, and increased fire frequency. But detailed knowledge about the dynamic state of permafrost...
Parasite invasion following host reintroduction: a case of Yellowstone’s wolves
Paul C. Cross, Emily S. Almberg, Andrew P. Dobson, Douglas W. Smith, Peter J. Hudson
2012, Philosophical Transactions of the Royal Society B: Biological Sciences (367) 2840-2851
Wildlife reintroductions select or treat individuals for good health with the expectation that these individuals will fare better than infected animals. However, these individuals, new to their environment, may also be particularly susceptible to circulating infections and this may result in high morbidity and mortality, potentially jeopardizing the goals of...
Patterns of mortality in free-ranging California condors (Gymnogyps californianus)
B.A. Rideout, I. Stalis, R. Papendick, A. Pessier, B. Puschner, M.E. Finkelstein, D. R. Smith, Matthew Johnson, M. Mace, R. Stroud, J. Brandt, J. Burnett, C. Parish, J. Petterson, C. Witte, C. Stringfield, K. Orr, J. Zuba, M. Wallace, J. Grantham
2012, Journal of Wildlife Diseases (48) 95-112
We document causes of death in free-ranging California Condors (Gymnogyps californianus) from the inception of the reintroduction program in 1992 through December 2009 to identify current and historic mortality factors that might interfere with establishment of self-sustaining populations in the wild. A total of 135 deaths occurred from October 1992...