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Page 70, results 1726 - 1750

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Not all publications have extents, not all extents are completely accurate
Osmoregulatory physiology and rapid evolution of salinity tolerance in threespine stickleback recently introduced to fresh water
Jeffrey N Divino, Michelle Y. Monette, Stephen D. McCormick, Paul H. Yancey, Kyle G. Flannery, Michael A. Bell, Jennifer L. Rollins, Frank A. von Hippel, Eric T. Schultz
2016, Evolutionary Ecology Research (17) 179-201
Background: Post-Pleistocene diversification of threespine stickleback in fresh water offers a valuable opportunity to study how changes in environmental salinity shape physiological evolution in fish. In Alaska, the presence of both ancestral oceanic populations and derived landlocked populations, including recent lake introductions, allows us to examine rates and direction of evolution...
Pacific walrus coastal haulout database, 1852-2016— Background report
Anthony S. Fischbach, Anatoly A. Kochnev, Joel L. Garlich-Miller, Chadwick V. Jay
2016, Open-File Report 2016-1108
Walruses are large benthic predators that rest out of water between foraging bouts. Coastal “haulouts” (places where walruses rest) are formed by adult males in summer and sometimes by females and young when sea ice is absent, and are often used repeatedly across seasons and years. Understanding the geography and historical...
Arctic sea ice decline contributes to thinning lake ice trend in northern Alaska
Vladimir Alexeev, Christopher D. Arp, Benjamin M. Jones, Lei Cai
2016, Environmental Research Letters (11)
Field measurements, satellite observations, and models document a thinning trend in seasonal Arctic lake ice growth, causing a shift from bedfast to floating ice conditions. September sea ice concentrations in the Arctic Ocean since 1991 correlate well (r = +0.69,p < 0.001) to this lake regime shift. To understand how and to what extent...
The Water-Quality Partnership for National Parks—U.S. Geological Survey and National Park Service, 1998–2016
Mark A. Nilles, Pete E Penoyer, Amy S. Ludtke, Alan C. Ellsworth
2016, Fact Sheet 2016-3041
The U.S. Geological Survey (USGS) and the National Park Service (NPS) work together through the USGS–NPS Water-Quality Partnership to support a broad range of policy and management needs related to high-priority water-quality issues in national parks. The program was initiated in 1998 as part of the Clean Water Action Plan,...
A synthesis of Jurassic and Early Cretaceous crustal evolution along the southern margin of the Arctic Alaska–Chukotka microplate and implications for defining tectonic boundaries active during opening of Arctic Ocean basins
Alison B. Till
2016, Lithosphere (8) 219-237
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...
Mineral deposits and metallogeny of Alaska
Richard J. Goldfarb, Corey J. Meighan, Lawrence D. Meinert, Frederic H. Wilson
2016, Book chapter, Mineral resources in the Arctic
Alaska, the largest State within the United States, and mainly located north of latitude 60°, is an important part of the Circum-Arctic region. Alaska is a richly endowed region with a long and complex geologic history. The mining history is short by world standards but nevertheless there are a number...
Hyperspectral surveying for mineral resources in Alaska
Raymond F. Kokaly, Garth E. Graham, Todd M. Hoefen, Karen D. Kelley, Michaela R. Johnson, Bernard E. Hubbard
2016, Fact Sheet 2016-3029
Alaska is a major producer of base and precious metals and has a high potential for additional undiscovered mineral resources. However, discovery is hindered by Alaska’s vast size, remoteness, and rugged terrain. New methods are needed to overcome these obstacles in order to fully evaluate Alaska’s geology and mineral resource...
Detection, prevalence, and transmission of avian hematozoa in waterfowl at the Arctic/sub-Arctic interface: co-infections, viral interactions, and sources of variation.
Brandt W. Meixell, Todd W. Arnold, Mark S. Lindberg, Matthew M. Smith, Andrew M. Ramey, Jonathan A. Runstadler
2016, Parasites & Vectors (9)
Background: The epidemiology of avian hematozoa at high latitudes is still not well understood, particularly in sub-Arctic and Arctic habitats, where information is limited regarding seasonality and range of transmission, co-infection dynamics with parasitic and viral agents, and possible fitness consequences of infection. Such information is important as climate warming...
Forecasting the relative influence of environmental and anthropogenic stressors on polar bears
Todd C. Atwood, Bruce G. Marcot, David C. Douglas, Steven C. Amstrup, Karyn D. Rode, George M. Durner, Jeffrey F. Bromaghin
2016, Ecosphere (7)
Effective conservation planning requires understanding and ranking threats to wildlife populations. We developed a Bayesian network model to evaluate the relative influence of environmental and anthropogenic stressors, and their mitigation, on the persistence of polar bears (Ursus maritimus). Overall sea ice conditions, affected by rising global temperatures, were the most...
Identifying Kittlitz's Murrelet nesting habitat in North America at the landscape scale
Jonathan J. Felis, Michelle L. Kissling, Robb S.A. Kaler, Leah A. Kenney, Matthew J. Lawonn
2016, Journal of Fish and Wildlife Management (7) 323-333
The Kittlitz's Murrelet (Brachyramphus brevirostris) is a small, non-colonial seabird endemic to marine waters of Alaska and eastern Russia that may have experienced significant population decline in recent decades, in part because of low reproductive success and terrestrial threats. Although recent studies have shed new light on Kittlitz's Murrelet nesting...
Blood selenium concentrations in female Pacific black brant molting in Arctic Alaska: Relationships with age and habitat salinity
J. Christian Franson, Paul L. Flint, Joel A. Schmutz
2016, Marine Pollution Bulletin (111) 453-455
Blood samples collected from 81 female Pacific black brant (Branta bernicla nigricans) molting near Teshekpuk Lake, Alaska, were analyzed for selenium concentration. The concentration of selenium in blood of after second year (hatched two or more years ago) females (0.84 μg/g wet weight) was significantly greater than the concentration in second...
A point mutation in the polymerase protein PB2 allows a reassortant H9N2 influenza isolate of wild-bird origin to replicate in human cells.
Islam T.M. Hussein, Eric J. Ma, Brandt W. Meixell, Nichola J. Hill, Mark S. Lindberg, Randy A. Albrecht, Justin Bahl, Jonathan A. Runstadler
2016, Infection, Genetics and Evolution (41) 279-288
H9N2 influenza A viruses are on the list of potentially pandemic subtypes. Therefore, it is important to understand how genomic reassortment and genetic polymorphisms affect phenotypes of H9N2 viruses circulating in the wild bird reservoir. A comparative genetic analysis of North American H9N2 isolates of wild bird origin identified a...
Automated mapping of persistent ice and snow cover across the western U.S. with Landsat
David J. Selkowitz, Richard R. Forster
2016, ISPRS Journal of Photogrammetry and Remote Sensing (117) 126-140
We implemented an automated approach for mapping persistent ice and snow cover (PISC) across the conterminous western U.S. using all available Landsat TM and ETM+ scenes acquired during the late summer/early fall period between 2010 and 2014. Two separate validation approaches indicate this dataset provides...
Increased water deficit decreases Douglas fir growth throughout western US forests
Christina M Restaino, David L. Peterson, Jeremy S. Littell
2016, Proceedings of the National Academy of Sciences of the United States of America (113) 9557-9562
Changes in tree growth rates can affect tree mortality and forest feedbacks to the global carbon cycle. As air temperature increases, evaporative demand also increases, increasing effective drought in forest ecosystems. Using a spatially comprehensive network of Douglas-fir (Pseudotsuga menziesii) chronologies from 122 locations that experience distinctly different climate in...
Spatiotemporal patterns of mercury accumulation in lake sediments of western North America
Paul Drevnick, Colin A. Cooke, Daniella Barraza, Jules M. Blais, Kenneth Coale, Brian F. Cumming, Chris Curtis, Biplob Das, William F. Donahue, Collin A. Eagles-Smith, Daniel R. Engstrom, William F. Fitzgerald, Chad V. Furl, John R. Gray, Roland I. Hall, Togwell A. Jackson, Kathleen R. Laird, W. Lyle Lockhart, Robie W. Macdonald, M. Alisa Mast, Callie Mathieu, Derek C.G. Muir, Peter Outridge, Scott Reinemann, Sarah E. Rothenberg, Ana Carolina Ruiz-Fernandex, Louis, Rhea Sanders, Hamed Sanei, Elliott Skierszkan, Peter C. Van Metre, Timothy Veverica, Johan A. Wiklund, Brent B. Wolfe
2016, Science of the Total Environment (568) 1157-1170
For the Western North America Mercury Synthesis, we compiled mercury records from 165 dated sediment cores from 138 natural lakes across western North America. Lake sediments are accepted as faithful recorders of historical mercury accumulation rates, and regional and sub-regional temporal and spatial trends were...
Threshold sensitivity of shallow Arctic lakes and sublake permafrost to changing winter climate
Christopher D. Arp, Benjamin M. Jones, Guido Grosse, Allen C. Bondurant, Vladimir E. Romanovksy, Kenneth M. Hinkel, Andrew D. Parsekian
2016, Geophysical Research Letters (43) 6358-6365
Interactions and feedbacks between abundant surface waters and permafrost fundamentally shape lowland Arctic landscapes. Sublake permafrost is maintained when the maximum ice thickness (MIT) exceeds lake depth and mean annual bed temperatures (MABTs) remain below freezing. However, declining MIT since the 1970s is likely causing talik development below...
Effects of Lead Exposure, Environmental Conditions, and Metapopulation Processes on Population Dynamics of Spectacled Eiders.
Paul L. Flint, J. Barry Grand, Margaret R. Petersen, Robert F. Rockwell
2016, North American Fauna (81) 1-41
Spectacled eider Somateria fischeri numbers have declined and they are considered threatened in accordance with the US Endangered Species Act throughout their range. We synthesized the available information for spectacled eiders to construct deterministic, stochastic, and metapopulation models for this species that incorporated current estimates of vital rates such as...
Genome sequence of a novel H14N7 subtype influenza A virus isolated from a blue-winged teal (Anas discors) harvested in Texas, USA
Andrew M. Ramey, Andrew B. Reeves, Rebecca L. Poulson, Deborah L. Carter, Nicholas Davis-Fields, David E. Stallknecht
2016, Genome Announcements (4)
We report here the complete genome sequence of a novel H14N7 subtype influenza A virus (IAV) isolated from a blue-winged teal (Anas discors) harvested in Texas, USA. The genomic characteristics of this IAV strain with a previously undetected subtype combination suggest recent viral evolution within the New World wild-bird IAV...
Waterfowl populations are resilient to immediate and lagged impacts of wildfires in the boreal forest
Tyler Lewis, Joel A. Schmutz, Courtney L. Amundson, Mark S. Lindberg
2016, Journal of Applied Ecology (53)
Summary 1. Wildfires are the principal disturbance in the boreal forest, and their size and frequency are increasing as the climate warms. Impacts of fires on boreal wildlife are largely unknown, especially for the tens of millions of waterfowl that breed in the region. This knowledge gap creates significant barriers...
Surface water connectivity drives richness and composition of Arctic lake fish assemblages
Sarah M. Laske, Trevor B. Haynes, Amanda E. Rosenberger, Joshua C. Koch, Mark S. Wipfli, Matthew Whitman, Christian E. Zimmerman
2016, Freshwater Biology (61) 1090-1104
Surface water connectivity can influence the richness and composition of fish assemblages, particularly in harsh environments where colonisation factors and access to seasonal refugia are required for species persistence. Studies regarding influence of connectivity on Arctic fish distributions are limited and are rarely applied to whole assemblage patterns....
The geochemical atlas of Alaska, 2016
Gregory K. Lee, Douglas B. Yager, Jeffrey L. Mauk, Matthew Granitto, Paul Denning, Bronwen Wang, Melanie B. Werdon
2016, Data Series 908
A rich legacy of geochemical data produced since the early 1960s covers the great expanse of Alaska; careful treatment of such data may provide significant and revealing geochemical maps that may be used for landscape geochemistry, mineral resource exploration, and geoenvironmental investigations over large areas. To maximize the spatial density...
Elements in whole blood of Northwestern Crows (Corvus caurinus) in Alaska: No evidence for an association with beak deformities
Caroline R. Van Hemert, Colleen M. Handel
2016, Journal of Wildlife Diseases (52) 713-718
A recent outbreak of beak deformities among resident birds in Alaska has raised concern about environmental contamination as a possible underlying factor. We measured whole blood concentrations of 30 essential and nonessential elements to determine whether any were associated with beak deformities in Northwestern Crows (Corvus caurinus). We tested for...
Evidence for the exchange of blood parasites between North America and the Neotropics in blue-winged teal (Anas discors)
Andrew M. Ramey, John A. Reed, Patrick Walther, Paul Link, Joel A. Schmutz, David C. Douglas, David E. Stallknecht, Catherine Soos
2016, Parasitology Research (115) 3923-3939
Blue-winged teal (Anas discors) are abundant, small-bodied dabbling ducks that breed throughout the prairies of the northcentral USA and central Canada and that winter in the southern USA and northern Neotropics. Given the migratory tendencies of this species, it is plausible that blue-winged teal may disperse avian pathogens,...
Wildfire risk as a socioecological pathology
A. Paige Fischer, Thomas A. Spies, Toddi A Steelman, Cassandra Moseley, Bart R. Johnson, John D. Bailey, Alan A Ager, Patrick S. Bourgeron, Susan Charnley, Brandon M. Collins, Jeffrey D Kline, Jessica E Leahy, Jeremy S. Littell, James D. A. Millington, Max Nielsen-Pincus, Christine S Olsen, Travis B Paveglio, Christopher I. Roos, Michelle M Steen-Adams, Forrest R Stevens, Jelena Vukomanovic, Eric M White, David M J S Bowman
2016, Frontiers in Ecology and the Environment (14) 276-284
Wildfire risk in temperate forests has become a nearly intractable problem that can be characterized as a socioecological “pathology”: that is, a set of complex and problematic interactions among social and ecological systems across multiple spatial and temporal scales. Assessments of wildfire risk could benefit from recognizing and accounting for...
Models for ecological models: Ocean primary productivity
Christopher K. Wikle, William B. Leeds, Mevin Hooten
2016, CHANCE (29) 23-30
The ocean accounts for more than 70% of planet Earth's surface, and it processes are critically important to marine and terrestrial life.  Ocean ecosystems are strongly dependent on the physical state of the ocean (e.g., transports, mixing, upwelling, runoff, and ice dynamics(.  As an example, consider the Coastal Gulf of...