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Page 58, results 1426 - 1450

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Landscapes and seascapes and tectonics
Warren J. Nokleberg, David Scholl, Thomas K. Bundtzen, David B. Stone
Thomas K. Bundtzen, Warren J. Nokleberg, Raymond A. Price, David W. Scholl, David B. Stone, editor(s)
2017, Book chapter, Dynamic geology of the Northern Cordillera (Alaska and western Canada) and adjacent marine areas: Tectonics, hazards, and resources
No abstract available....
Environmental and behavioral changes may influence the exposure of an Arctic apex predator to pathogens and contaminants
Todd C. Atwood, Colleen G. Duncan, Kelly A. Patyk, Pauline Nol, Jack Rhyan, Matthew McCollum, Melissa A. McKinney, Andrew M. Ramey, Camila Cerqueira-Cezar, Oliver C H Kwok, Jitender P Dubey, S.G. Hennager
2017, Scientific Reports (7)
Recent decline of sea ice habitat has coincided with increased use of land by polar bears (Ursus maritimus) from the southern Beaufort Sea (SB), which may alter the risks of exposure to pathogens and contaminants. We assayed blood samples from SB polar bears to assess prior exposure to the pathogens...
Temporal complexity of southern Beaufort Sea polar bear diets during a period of increasing land use
Melissa A. McKinney, Todd C. Atwood, Sara J. Iverson, Elizabeth L. Peacock
2017, Ecosphere (8)
From 2000 to 2013, use of land as a seasonal habitat by polar bears (Ursus maritimus) of the southern Beaufort Sea (SB) subpopulation substantially increased. This onshore use has been linked to reduced spatial and temporal availability of sea ice, as well as to the availability of subsistence‐harvested bowhead whale...
Relative influences of climate change and human activity on the onshore distribution of polar bears
Ryan H. Wilson, Eric V. Regehr, Michelle St. Martin, Todd C. Atwood, Elizabeth L. Peacock, Susanne Miller, George J. Divoky
2017, Biological Conservation (214) 288-294
Climate change is altering habitat for many species, leading to shifts in distributions that can increase levels of human-wildlife conflict. To develop effective strategies for minimizing human-wildlife conflict, we must understand the relative influences that climate change and other factors have on wildlife distributions. Polar bears (Ursus maritimus) are increasingly...
Demographic and temporal variations in immunity and condition of polar bears (Ursus maritimus) from the southern Beaufort Sea
Lorin Neuman-Lee, Patricia Terletzky, Todd C. Atwood, Eric Gese, Geoffrey Smith, Sydney Greenfield, John Pettit, Susannah French
2017, Journal of Experimental Zoology Part A: Ecological Genetics and Physiology (327) 333-346
Assessing the health and condition of animals in their natural environment can be problematic. Many physiological metrics, including immunity, are highly influenced by specific context and recent events to which researchers may be unaware. Thus, using a multifaceted physiological approach and a context-specific analysis encompassing multiple time scales can be...
Polar bear attacks on humans: Implications of a changing climate
James Wilder, Dag Vongraven, Todd C. Atwood, Bob Hansen, Amalie Jessen, Anatoly A. Kochnev, Geoff York, Rachel Vallender, Daryll Hedman, Melissa Gibbons
2017, Wildlife Society Bulletin (41) 537-547
Understanding causes of polar bear (Ursus maritimus) attacks on humans is critical to ensuring both human safety and polar bear conservation. Although considerable attention has been focused on understanding black (U. americanus) and grizzly (U. arctos) bear conflicts with humans, there have been few attempts to systematically collect, analyze, and...
Movements and habitat use of White-fronted Geese (Anser albifrons frontalis) during the remigial molt in arctic Alaska, USA
Paul L. Flint, Brandt W. Meixell
2017, Waterbirds (40) 272-281
Proposed oil and gas leasing in the National Petroleum Reserve - Alaska has raised questions about possible impacts of development on molting Greater White-fronted Geese (Anser albifrons frontalis) and their habitats. We used GPS transmitters to record fine-scale location data of molting and post-molt White-fronted Geese to assess patterns of...
Best practices for assessing forage fish fisheries-seabird resource competition
William J. Sydeman, Sarah Ann Thompson, Tycho Anker-Nilssen, Mayumi L. Arimitsu, Ashley Bennison, Sophie Bertrand, Philipp Boersch-Supan, Charlotte Boyd, Nicole C. Bransome, Robert J.M. Crawford, Francis Daunt, Robert W. Furness, Dimas Gianuca, Amanda Gladics, Laura Koehn, Jennifer W. Lang, Elizabeth Loggerwell, Taryn L. Morris, Elizabeth M. Phillips, Jennifer Provencher, André E. Punt, Claire Saraux, Lynne Shannon, Richard B. Sherley, Alejandro Simeone, Ross M. Wanless, Sarah Wanless, Stephani Zador
2017, Fisheries Research (194) 209-221
Worldwide, in recent years capture fisheries targeting lower-trophic level forage fish and euphausiid crustaceans have been substantial (∼20 million metric tons [MT] annually). Landings of forage species are projected to increase in the future, and this harvest may affect marine ecosystems and predator-prey interactions by removal or redistribution of biomass...
Remote measurement of river discharge using thermal particle image velocimetry (PIV) and various sources of bathymetric information
Carl J. Legleiter, Paul J. Kinzel, Jonathan M. Nelson
2017, Journal of Hydrology (554) 490-506
Although river discharge is a fundamental hydrologic quantity, conventional methods of streamgaging are impractical, expensive, and potentially dangerous in remote locations. This study evaluated the potential for measuring discharge via various forms of remote sensing, primarily thermal imaging of flow velocities but also spectrally-based depth retrieval from passive optical image...
U.S. Geological Survey experience with the residual absolutes method
E. William Worthington, Jurgen Matzka
2017, Geoscientific Instrumentation, Methods and Data Systems (6) 419-427
The U.S. Geological Survey (USGS) Geomagnetism Program has developed and tested the residual method of absolutes, with the assistance of the Danish Technical University's (DTU) Geomagnetism Program. Three years of testing were performed at College Magnetic Observatory (CMO), Fairbanks, Alaska, to compare the residual method with the null method. Results show that the two...
Recurrent Holocene movement on the Susitna Glacier Thrust Fault: The structure that initiated the Mw 7.9 Denali Fault earthquake, central Alaska
Stephen Personius, Anthony J. Crone, Patricia A. Burns, Nadine G. Reitman
2017, Bulletin of the Seismological Society of America (107) 1593-1609
We conducted a trench investigation and analyzed pre‐ and postearthquake topography to determine the timing and size of prehistoric surface ruptures on the Susitna Glacier fault (SGF), the thrust fault that initiated the 2002 Mw 7.9 Denali fault earthquake sequence in central Alaska. In two of our three hand‐excavated trenches, we found...
Future of Pacific salmon in the face of environmental change: Lessons from one of the world's remaining productive salmon regions
Erik R. Schoen, Mark S. Wipfli, Jamie Trammell, Daniel J. Rinella, Angelica L. Floyd, Jess Grunblatt, Molly D. McCarthy, Benjamin E. Meyer, John M. Morton, James E. Powell, Anupma Prakash, Matthew N. Reimer, Svetlana L. Stuefer, Horacio Toniolo, Brett M. Wells, Frank D. W. Witmer
2017, Fisheries (42) 538-553
Pacific salmon Oncorhynchus spp. face serious challenges from climate and landscape change, particularly in the southern portion of their native range. Conversely, climate warming appears to be allowing salmon to expand northwards into the Arctic. Between these geographic extremes, in the Gulf of Alaska region, salmon are at historically high abundances but...
Harvesting wildlife affected by climate change: a modelling and management approach for polar bears
Eric V. Regehr, Ryan H. Wilson, Karyn D. Rode, Michael C. Runge, Harry Stern
2017, Journal of Applied Ecology (54) 1534-1543
The conservation of many wildlife species requires understanding the demographic effects of climate change, including interactions between climate change and harvest, which can provide cultural, nutritional or economic value to humans.We present a demographic model that is based on the polar bear Ursus maritimus life cycle and includes density-dependent...
Continuously amplified warming in the Alaskan Arctic: Implications for estimating global warming hiatus
Kang Wang, Tingjun Zhang, Xiangdong Zhang, Gary D. Clow, Elchin E. Jafarov, Irina Overeem, Vladimir Romanovsky, Xiaoqing Peng, Bin Cao
2017, Geophysical Research Letters (44) 9029-9038
Historically, in situ measurements have been notoriously sparse over the Arctic. As a consequence, the existing gridded data of surface air temperature (SAT) may have large biases in estimating the warming trend in this region. Using data from an expanded monitoring network with 31 stations in the Alaskan Arctic, we...
Challenges and solutions for applying the travel cost demand model to geographically remote visitor destinations: A case study of bear viewing at Katmai National Park and Preserve
Leslie Richardson, Christopher Huber, John B. Loomis
2017, Human Dimensions of Wildlife (22) 550-563
Remote and unique destinations present difficulties when attempting to construct traditional travel cost models to value recreation demand. The biggest limitation comes from the lack of variation in the dependent variable, defined as the number of trips taken over a set time frame. There are various approaches that can be...
Surveillance for highly pathogenic influenza A viruses in California during 2014–2015 provides insights into viral evolutionary pathways and the spatiotemporal extent of viruses in the Pacific Americas Flyway
Andrew M. Ramey, Nichola J. Hill, Troy Cline, Magdalena Plancarte, Susan De La Cruz, Michael L. Casazza, Joshua T. Ackerman, Joseph P. Fleskes, T. Winston Vickers, Andrew B. Reeves, Frances Gulland, Christine Fontaine, Diann J. Prosser, Jonathan Runstadler, Walter M. Boyce
2017, Emerging Microbes & Infections (6) 1-10
We used surveillance data collected in California before, concurrent with, and subsequent to an outbreak of highly pathogenic (HP) clade 2.3.4.4 influenza A viruses (IAVs) in 2014–2015 to (i) evaluate IAV prevalence in waterfowl, (ii) assess the evidence for spill-over infections in marine mammals and (iii) genetically characterize low-pathogenic (LP)...
Prey partitioning and use of insects by juvenile sockeye salmon and a potential competitor, threespine stickleback, in Afognak Lake, Alaska
Natura Richardson, Anne H. Beaudreau, Mark S. Wipfli, Heather Finkle
2017, Ecology of Freshwater Fish (26) 586-601
Freshwater growth of juvenile sockeye salmon (Oncorhynchus nerka) depends upon the quality and quantity of prey and interactions with potential competitors in the foraging environment. To a large extent, knowledge about the ecology of lake-rearing juvenile sockeye salmon has emerged from studies of commercially important runs returning to deep nursery...
2015 Volcanic activity in Alaska—Summary of events and response of the Alaska Volcano Observatory
James P. Dixon, Cheryl E. Cameron, Alexandra M. Iezzi, Kristi L. Wallace
2017, Scientific Investigations Report 2017-5104
The Alaska Volcano Observatory (AVO) responded to eruptions, volcanic unrest or suspected unrest, and seismic events at 14 volcanic centers in Alaska during 2015. The most notable volcanic activity consisted of continuing intermittent ash eruptions from Cleveland and Shishaldin volcanoes in the Aleutian Islands. Two eruptive episodes, at Veniaminof and...
National assessment of shoreline change—Summary statistics for updated vector shorelines and associated shoreline change data for the north coast of Alaska, U.S.-Canadian Border to Icy Cape
Ann E. Gibbs, Bruce M. Richmond
2017, Open-File Report 2017-1107
Long-term rates of shoreline change for the north coast of Alaska, from the U.S.-Canadian border to the Icy Cape region of northern Alaska, have been updated as part of the U.S. Geological Survey’s National Assessment of Shoreline Change Project. Short-term shoreline change rates are reported for the first time. Additional...
Fatal attraction? Intraguild facilitation and suppression among predators
Kelly J. Sivy, Casey B. Pozzanghera, James B. Grace, Laura R. Prugh
2017, The American Naturalist (190) 663-679
Competition and suppression are recognized as dominant forces that structure predator communities. Facilitation via carrion provisioning, however, is a ubiquitous interaction among predators that could offset the strength of suppression. Understanding the relative importance of these positive and negative interactions is necessary to anticipate community-wide responses to apex predator declines...
Glacial conditioning of stream position and flooding in the braid plain of the Exit Glacier foreland, Alaska
Janet H. Curran, Michael G. Loso, Haley B. Williams
2017, Geomorphology (293 ) 272-288
Flow spilling out of an active braid plain often signals the onset of channel migration or avulsion to previously occupied areas. In a recently deglaciated environment, distinguishing between shifts in active braid plain location, considered reversible by fluvial processes at short timescales, and more permanent glacier-conditioned changes in stream position can be critical to...
Effects of surgically implanted transmitters on reproduction and survival in mallards
Jennifer Sheppard, Todd W. Arnold, Courtney L. Amundson, David Klee
2017, Wildlife Society Bulletin (41) 597-604
Abdominally implanted radiotransmitters have been widely used in studies of waterbird ecology; however, the longer handling times and invasiveness of surgical implantation raise important concerns about animal welfare and potential effects on data quality. Although it is difficult to assess effects of handling and marking wild animals by comparing them...
Neotectonics of interior Alaska and the late Quaternary slip rate along the Denali fault system
Peter J. Haeussler, Ari Matmon, David P. Schwartz, Gordon G. Seitz
2017, Geosphere (13) 1-19
The neotectonics of southern Alaska (USA) are characterized by a several hundred kilometers–wide zone of dextral transpressional that spans the Alaska Range. The Denali fault system is the largest active strike-slip fault system in interior Alaska, and it produced a Mw 7.9 earthquake in 2002. To evaluate the late Quaternary slip...
Deep-sea coral research and technology program: Alaska deep-sea coral and sponge initiative final report
Chris Rooper, Robert P. Stone, Peter Etnoyer, Christina Conrath, Jennifer Reynolds, H. Gary Greene, Branwen Williams, Enrique Salgado, Cheryl L. Morrison, Rhian G. Waller, Amanda W.J. Demopoulos
2017, NOAA Technical Memorandum NMFS-OHC-2
Deep-sea coral and sponge ecosystems are widespread throughout most of Alaska’s marine waters. In some places, such as the central and western Aleutian Islands, deep-sea coral and sponge resources can be extremely diverse and may rank among the most abundant deep-sea coral and sponge communities in the world. Many different...
QFASAR: Quantitative fatty acid signature analysis with R
Jeffrey F. Bromaghin
2017, Methods in Ecology and Evolution (8) 1158-1162
Knowledge of predator diets provides essential insights into their ecology, yet diet estimation is challenging and remains an active area of research.Quantitative fatty acid signature analysis (QFASA) is a popular method of estimating diet composition that continues to be investigated and extended. However, software to implement QFASA...