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Page 82, results 2026 - 2050

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Conclusions, synthesis, and future directions: understanding sources of population change
Daniel Esler, Paul L. Flint, Dirk V. Derksen, Jean-Pierre L. Savard, John M. Eadie
2015, Book chapter, Ecology and Conservation of North American Sea Ducks
The material in this volume reflects the burgeoning interest in sea ducks, both as study species with compelling and unique ecological attributes and as taxa of conservation concern. In this review, we provide perspective on the current state of sea duck knowledge by highlighting key findings in the preceding chapters...
Diet of yellow-billed loons (Gavia adamsii) in Arctic lakes during the nesting season inferred from fatty acid analysis
T B Haynes, Joel A. Schmutz, Jeffrey F. Bromaghin, S J Iverson, V. M. Padula, A E Rosenberger
2015, Polar Biology (38) 1239-1247
Understanding the dietary habits of yellow-billed loons (Gavia adamsii) can give important insights into their ecology, however, studying the diet of loons is difficult when direct observation or specimen collection is impractical. We investigate the diet of yellow-billed loons nesting on the Arctic Coastal Plain of Alaska using...
Can polar bears use terrestrial foods to offset lost ice-based hunting opportunities?
Karyn D. Rode, Charles T. Robbins, Lynne Nelson, Steven C. Amstrup
2015, Frontiers in Ecology and the Environment (13) 138-145
Increased land use by polar bears (Ursus maritimus) due to climate-change-induced reduction of their sea-ice habitat illustrates the impact of climate change on species distributions and the difficulty of conserving a large, highly specialized carnivore in the face of this global threat. Some authors have suggested that terrestrial food consumption...
Prevalence and genetic diversity of haematozoa in South American waterfowl and evidence for intercontinental redistribution of parasites by migratory birds
Matthew M. Smith, Andrew M. Ramey
2015, International Journal for Parasitology: Parasites and Wildlife (4) 22-28
To understand the role of migratory birds in the movement and transmission of haematozoa within and between continental regions, we examined 804 blood samples collected from eleven endemic species of South American waterfowl in Peru and Argentina for infection by Haemoproteus, Plasmodium, and/or Leucocytozono blood parasites. Infections were detected in...
A real-time, quantitative PCR protocol for assessing the relative parasitemia of Leucocytozoon in waterfowl
Matthew M. Smith, Joel A. Schmutz, Chloe Apelgren, Andrew M. Ramey
2015, Journal of Microbiological Methods (111) 72-77
Microscopic examination of blood smears can be effective at diagnosing and quantifying hematozoa infections. However, this method requires highly trained observers, is time consuming, and may be inaccurate for detection of infections at low levels of parasitemia. To develop a molecular methodology for identifying and quantifying Leucocytozoon parasite infection in...
Polygonal tundra geomorphological change in response to warming alters future CO2 and CH4 flux on the Barrow Peninsula
Mark J. Lara, A. David McGuire, Eugénie S. Euskirchen, Craig E. Tweedie, Kenneth M. Hinkel, Alexei N. Skurikhin, Vladimir E. Romanovsky, Guido Grosse, W. Robert Bolton, Helene Genet
2015, Global Change Biology (21) 1634-1651
The landscape of the Barrow Peninsula in northern Alaska is thought to have formed over centuries to millennia, and is now dominated by ice-wedge polygonal tundra that spans drained thaw-lake basins and interstitial tundra. In nearby tundra regions, studies have identified a rapid increase in thermokarst formation (i.e., pits) over...
A tribute to George Plafker
Gary S. Fuis, Peter J. Haeussler, Brian F. Atwater
2015, Quaternary Science Reviews (113) 3-7
In a long and distinguished career, George Plafker made fundamental advances in understanding of megathrust tectonics, tsunami generation, paleoseismology, crustal neotectonics, and Alaskan geology, chiefly by means of geological field observations. George discovered that giant earthquakes result from tens of meters of seismic slip on subduction megathrusts, and he did this...
Reconnaissance investigation of the Lisburne Group in the Cobblestone Creek area, Chandler Lake quadrangle, Alaska
Julie A. Dumoulin, Michael T. Whalen
M. A. Wartes, P. L. Decker, editor(s)
2015, Alaska Division of Geological & Geophysical Surveys Preliminary Interpretive Report 2015-2
A reconnaissance investigation of the Carboniferous Lisburne Group in the Cobblestone Creek area, Chandler Lake Quadrangle, yields insights into its resource potential and regional relations. Locally porous vuggy dolostone with hydrocarbon reservoir potential occurs in the lower Lisburne in the three most southerly of five thrust sheets, and contains traces...
Sampling of sea ducks for influenza A viruses in Alaska during winter provides lack of evidence for epidemiological peak of infection.
Andrew M. Ramey, Andrew B. Reeves, Rebecca L. Poulson, Jeff Wasley, Daniel Esler, David E. Stalknecht
2015, Journal of Wildlife Diseases (51) 938-941
Sampling of sea ducks for influenza A viruses in Alaska during winter provided no evidence for an epidemiologic peak of infection. Isolates were recovered, however, that provide information on viral diversity and dispersal that may not be realized through sampling efforts focused on other avian taxa....
Diverse juvenile life-history behaviours contribute to the spawning stock of an anadromous fish population
Timothy E. Walsworth, Daniel E. Schindler, Jennifer R. Griffiths, Christian E. Zimmerman
2015, Ecology of Freshwater Fish (24) 204-213
Habitat quality often varies substantially across space and time, producing a shifting mosaic of growth and mortality trade-offs across watersheds. Traditional studies of juvenile habitat use have emphasised the evolution of single optimal strategies that maximise recruitment to adulthood and eventual fitness. However, linking the distribution of individual behaviours that...
Ecological drivers of variation in tool-use frequency across sea otter populations
Jessica Fujii, Katherine Ralls, M. Tim Tinker
2015, Behavioral Ecology (26) 519-526
Sea otters are well-known tool users, employing objects such as rocks or shells to break open hard-shelled invertebrate prey. However, little is known about how the frequency of tool use varies among sea otter populations and the factors that drive these differences. We examined 17 years of observational data on...
'Is Ash Falling?', an online ashfall reporting tool in support of improved ashfall warnings and investigations of ashfall processes
Kristi L. Wallace, Seth Snedigar, Cheryl Cameron
2015, Journal of Applied Volcanology (4)
The primary volcano hazard in Alaska is airborne ash, which endangers aircraft flying the busy North Pacific air routes and consequently affects global commerce. Downwind ashfall is also a significant threat to commerce, transportation and day-to-day activities in nearby Alaska communities. A web-enabled database, "Is Ash Falling?" has been developed...
Evidence for the assimilation of ancient glacier organic carbon in a proglacial stream food web
Jason Fellman, Eran Hood, Peter A. Raymond, J.H. Hudson, Maura Bozeman, Mayumi L. Arimitsu
2015, Limnology and Oceanography (60) 1118-1128
We used natural abundance δ13C, δ15N, and Δ14C to compare trophic linkages between potential carbon sources (leaf litter, epilithic biofilm, and particulate organic matter) and consumers (aquatic macroinvertebrates and fish) in a nonglacial stream and two reaches of the heavily glaciated Herbert River. We tested the hypothesis that proglacial stream...
The 3D Elevation Program: summary for Nevada
William J. Carswell Jr.
2015, Fact Sheet 2015-3028
Elevation data are essential to a broad range of applications, including forest resources management, wildlife and habitat management, national security, recreation, and many others. For the State of Nevada, elevation data are critical for infrastructure and construction management, natural resources conservation, flood risk management, geologic resource assessment and hazard mitigation,...
Polar bear population dynamics in the southern Beaufort Sea during a period of sea ice decline
Jeffrey F. Bromaghin, Trent L. McDonald, Ian Stirling, Andrew E. Derocher, Evan S. Richardson, Eric V. Regehr, David C. Douglas, George M. Durner, Todd C. Atwood, Steven C. Amstrup
2015, Ecological Applications (25) 634-651
In the southern Beaufort Sea of the United States and Canada, prior investigations have linked declines in summer sea ice to reduced physical condition, growth, and survival of polar bears (Ursus maritimus). Combined with projections of population decline due to continued climate warming and the ensuing loss of sea ice...
Stable carbon and nitrogen isotope trophic enrichment factors for Steller sea lion vibrissae relative to milk and fish/invertebrate diets
Craig A. Stricker, Aaron M. Christ, Michael B. Wunder, Andrew C. Doll, Sean D. Farley, Lorrie D. Rea, David A. S. Rosen, R. D. Scherer, Dominic J. Tollit
2015, Marine Ecology Progress Series (523) 255-266
Nutritional constraints have been proposed as a contributor to population declines in the endangered Steller sea lion Eumetopias jubatus in some regions of the North Pacific. Isotopic analysis of vibrissae (whiskers) is a potentially useful approach to resolving the nutritional ecology of this species because long-term (up to 8 yr)...
The 3D Elevation Program: summary for West Virginia
William J. Carswell Jr.
2015, Fact Sheet 2015-3017
Elevation data are essential to a broad range of applications, including forest resources management, wildlife and habitat management, national security, recreation, and many others. For the State of West Virginia, elevation data are critical for natural resources conservation, flood risk management, forest resources management, infrastructure and construction management, agriculture and...
Observing a catastrophic thermokarst lake drainage in northern Alaska
Benjamin M. Jones, Christopher D. Arp
2015, Permafrost and Periglacial Processes (26) 119-128
The formation and drainage of thermokarst lakes have reshaped ice-rich permafrost lowlands in the Arctic throughout the Holocene. North of Teshekpuk Lake, on the Arctic Coastal Plain of northern Alaska, thermokarst lakes presently occupy 22.5% of the landscape, and drained thermokarst lake basins occupy 61.8%. Analysis of remotely sensed imagery...
A review of infectious agents in polar bears (Ursus maritimus) and their long-term ecological relevance
Anna C. Fagre, Kelly A. Patyk, Pauline Nol, Todd C. Atwood, Karsten Hueffer, Colleen G. Duncan
2015, EcoHealth (12) 528-539
Disease was a listing criterion for the polar bear (Ursus maritimus) as threatened under the Endangered Species Act in 2008; it is therefore important to evaluate the current state of knowledge and identify any information gaps pertaining to diseases in polar bears. We conducted a systematic literature review focused...
The 3D Elevation Program: summary for Pennsylvania
William J. Carswell Jr.
2015, Fact Sheet 2015-3019
Elevation data are essential to a broad range of applications, including forest resources management, wildlife and habitat management, national security, recreation, and many others. For the Commonwealth of Pennsylvania, elevation data are critical for natural resources conservation (including the effects of drilling for oil and natural gas), agriculture and precision...
The 3D Elevation Program: summary for Iowa
William J. Carswell Jr.
2015, Fact Sheet 2015-3018
Elevation data are essential to a broad range of applications, including forest resources management, wildlife and habitat management, national security, recreation, and many others. For the State of Iowa, elevation data are critical for agriculture and precision farming, infrastructure and construction management, natural resources conservation, flood risk management, water supply...
Great (≥Mw8.0) megathrust earthquakes and the subduction of excess sediment and bathymetrically smooth seafloor
David W. Scholl, Stephe H. Kirby, Roland E. von Huene, Holly F. Ryan, Ray E. Wells, Eric L. Geist
2015, Geosphere (11) 236-265
Using older and in part flawed data, Ruff (1989) suggested that thick sediment entering the subduction zone (SZ) smooths and strengthens the trench-parallel distribution of interplate coupling. This circumstance was conjectured to favor rupture continuation and the generation of high-magnitude (≥Mw8.0) interplate thrust (IPT) earthquakes. Using larger and...
Unusually loud ambient noise in tidewater glacier fjords: a signal of ice melt
Erin C. Pettit, Kevin M. Lee, Joel P. Brann, Jeffrey A. Nystuen, Preston S. Wilson, Shad O’Neel
2015, Geophysical Research Letters (42) 2309-2316
In glacierized fjords, the ice-ocean boundary is a physically and biologically dynamic environment that is sensitive to both glacier flow and ocean circulation. Ocean ambient noise offers insight into processes and change at the ice-ocean boundary. Here we characterize fjord ambient noise and show that the average noise levels are...
Resilience and risk: a demographic model to inform conservation planning for polar bears
Eric V. Regehr, Ryan H. Wilson, Karyn D. Rode, Michael C. Runge
2015, Open-File Report 2015-1029
Climate change is having widespread ecological effects, including loss of Arctic sea ice. This has led to listing of the polar bear (Ursus maritimus) and other ice-dependent marine mammals under the U.S. Endangered Species Act (ESA). Methods are needed to evaluate the effects of climate change on population persistence to...