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Page 44, results 1076 - 1100

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Selecting a landscape model for natural resource management applications
Robert E. Keane, Rachel A. Loehman, Lisa M. Holsinger
2019, Current Landscape Ecology Reports (4) 31-40
Purpose of Review: Climate change and associated ecological impacts have challenged many conventional, observation-based approaches for predicting ecosystem and landscape responses to natural resource management. Complex spatial ecological models provide powerful, flexible tools which managers and others can use to make inferences about management impacts on future, no-analog landscape conditions. However,...
Integrated modeling reveals shifts in waterfowl population dynamics under climate change
Qing Zhao, Scott Boomer, Andy Royle
2019, Ecography (42) 1470-1481
1. Climate change has been identified as one of the most important drivers of wildlife populations. The development of appropriate conservation strategies relies on reliable predictions of population responses to climate change, which require in-depth understanding of the complex relationships between climate and population dynamics through density dependent demographic processes....
Remote sensing of river flow in Alaska—New technology to improve safety and expand coverage of USGS streamgaging
Jeff Conaway, John R. Eggleston, Carl J. Legleiter, John Jones, Paul J. Kinzel, John W. Fulton
2019, Fact Sheet 2019-3024
The U.S. Geological Survey monitors water level (water surface elevation relative to an arbitrary datum) and measures streamflow in Alaska rivers to compute and compile river flow records for use by water resource planners, engineers, and land managers to design infrastructure, manage floodplains, and protect life, property, and aquatic resources....
Soil physical, hydraulic, and thermal properties in interior Alaska, USA: Implications for hydrologic response to thawing permafrost conditions
Brian A. Ebel, Joshua C. Koch, Michelle A. Walvoord
2019, Water Resources Research (55) 4427-4447
Boreal forest regions are a focal point for investigations of coupled water and biogeochemical fluxes in response to wildfire disturbances, climate warming, and permafrost thaw. Soil hydraulic, physical, and thermal property measurements for mineral soils in permafrost regions are limited, despite substantial influences on cryohydrogeologic model results. This work expands...
Permafrost collapse is accelerating carbon release
Merritt R. Turetsky, Benjamin W. Abbott, Miriam Jones, Katey Walter Anthony, David Olefeldt, Edward A. Schuur, Charles Koven, A.D. McGuire, Guido Grosse, Peter Kuhry, Gustaf Hugelius, David M. Lawrence, Carolyn Gibson, A. B. K. Sannel
2019, Nature (569) 32-34
This much is clear: the Arctic is warming fast, and frozen soils are starting to thaw, often for the first time in thousands of years. But how this happens is as murky as the mud that oozes from permafrost when ice melts.As the temperature of the ground rises above freezing,...
Identification of single nucleotide polymorphisms for use in a genetic stock identification system for greater white-fronted goose (Anser albifrons) subspecies wintering in California
Robert E. Wilson, Sarah A. Sonsthagen, Jeffrey M. DaCosta, Craig R. Ely, Michael D. Sorenson, Sandra L. Talbot
2019, Open-File Report 2019-1040
California provides wintering habitat for most greater white-fronted geese (Anser albifrons [GWFG]) in the Pacific Flyway and this population has rapidly increased since the 1980s. Increased harvest of GWFG wintering in California may prevent agricultural depredation while providing increased hunting opportunities. However, changes in harvest levels are unlikely to...
The complimentary role of lentic and lotic habitats for Arctic grayling in a complex stream-lake network in Arctic Alaska
Mark S. Wipfli, Kurt C. Heim1, Christopher D. Arp2, Matthew S. Whitman3
2019, Ecology of Freshwater Fish (28) 209-221
Lakes can be important to stream dwelling fishes, yet how individuals exploit habitat heterogeneity across complex stream-lake networks is poorly understood. Furthermore, despite growing awareness that intermittent streams are widely used by fish, studies documenting use of seasonally accessible lakes remain scarce. We studied Arctic grayling (Thymallus arcticus) in a...
Gas hydrate production testing – Knowledge gained
Timothy S. Collett
2019, Conference Paper, Proceedings of the Offshore Technology Conference
Since their initial discovery in the 1960’s, gas hydrates have been considered to be an important potential source of unconventional natural gas. Significant progress has been made relative to our understanding of the geologic and engineering controls on the ultimate energy potential of gas hydrate; however, more work is required...
Cloud cover and delayed herbivory relative to timing of spring onset interact to dampen climate change impacts on net ecosystem exchange in a coastal Alaskan wetland
Josh Leffler, Karen H. Beard, Katharine C. Kelsey, Ryan T. Choi, Joel A. Schmutz, Jeffrey Welker
2019, Environmental Research Letters (14)
Rapid warming in northern ecosystems over the past four decades has resulted in earlier spring, increased precipitation, and altered timing of plant–animal interactions, such as herbivory. Advanced spring phenology can lead to longer growing seasons and increased carbon (C) uptake. Greater precipitation coincides with greater cloud cover possibly suppressing photosynthesis....
Monitoring annual trends in abundance of eelgrass (Zostera marina) at Izembek National Wildlife Refuge, Alaska, 2018
David H. Ward, Courtney L. Amundson
2019, Open-File Report 2019-1042
A lagoon-wide, point-sampling survey of eelgrass (Zostera marina) abundance was conducted in Izembek Lagoon, Alaska, August 7–16, 2018, the ninth year of annual surveys (2007–11, 2015–18). Mean predicted aboveground biomass of eelgrass across 116 sampled points was 238 grams per square meter (g m-2) (95 percent confidence interval: 203–278 g...
Evolution of the Arctic Alaska Sedimentary Basin
David W. Houseknecht
2019, Book chapter, Sedimentary Basins of the United States and Canada
The Arctic Alaska basin occupies the eastern part of the Arctic Alaska – Chukotka microplate, which rifted from the Canadian Arctic margin during opening of the Canada Basin. Stratigraphy comprises four tectonostratigraphic sequences. (1) The Devonian and older Franklinian sequence consists of sedimentary and metasedimentary rocks deposited on the Arctic...
Phenological mismatch between season advancement and migration timing alters Arctic plant traits
Ryan T. Choi, Karen H. Beard, A. Joshua Leffler, Katharine C. Kelsey, Joel A. Schmutz, Jeffrey Welker
2019, Journal of Ecology (107) 2503-2518
1. Climate change is creating phenological mismatches between herbivores and their plant resources throughout the Arctic. While advancing growing seasons and changing arrival times of migratory herbivores has been shown to have consequences for herbivores and forage quality, developing mismatches are also likely to influence other traits of plants, such as...
Carbon dioxide enhanced oil recovery and residual oil zone studies at the U.S. Geological Survey
Peter D. Warwick, Emil D. Attanasi, Madalyn S. Blondes, Sean T. Brennan, Marc L. Buursink, Colin A. Doolan, Philip A. Freeman, Hossein Jahediesfanjani, C. Özgen Karacan, Celeste D. Lohr, Matthew D. Merrill, Ricardo A. Olea, Jacqueline N. Roueché, Jenna L. Shelton, Ernie Slucher, Brian A. Varela, Mahendra K. Verma
2019, Conference Paper
The U.S. Geological Survey (USGS) is preparing a national resource assessment of the potential hydrocarbons recoverable after injection of carbon dioxide (CO2) into conventional oil reservoirs in the United States. The implementation of CO2-enhanced oil recovery (CO2-EOR) techniques can increase hydrocarbon production, and lead to incidental retention of CO2 in...
Alaska Shorebird Conservation Plan, Version III
Daniel R. Ruthrauff
2019, Book
In recognition of declines among perhaps half of Alaska’s breeding shorebirds, ongoing or emerging threats to shorebirds and their habitats, and considerable knowledge of Alaska’s shorebirds acquired over the past decade, the Alaska Shorebird Group decided that the Alaska Shorebird Conservation Plan was due for updates. Similar to Version II...
Satellite tracking of gulls and genomic characterization of fecal bacteria reveals environmentally mediated acquisition and dispersal of antimicrobial resistant Escherichia coli on the Kenai Peninsula, Alaska
Christina Ahlstrom, Jonas Bonnedahl, Hanna Woksepp, Jorge Hernandez, John Reed, T. Lee Tibbitts, Björn Olsen, David C. Douglas, Andrew M. Ramey
2019, Molecular Ecology (28) 2531-2545
Gulls (Larus spp.) have frequently been reported to carry Escherichia coli exhibiting antimicrobial resistance (AMR E. coli); however, the pathways governing the acquisition and dispersal of such bacteria are not well-described. We equipped 17 landfill-foraging gulls with satellite transmitters and collected gull fecal samples longitudinally from four locations on the...
The rise of an apex predator following deglaciation
Mevin Hooten, George G. Esslinger
2019, Diversity and Distributions (25) 895-908
AimSea otters (Enhydra lutris) are an apex predator of the nearshore marine community and nearly went extinct at the turn of the 20th century. Reintroductions and legal protection allowed sea otters to re‐colonize much of their former range. Our objective was to chronicle the colonization of...
Changes in behavior are unable to disrupt a trophic cascade involving a specialist herbivore and its food plant
Madeleine G Lohman, Thomas V. Riecke, Cheyenne R Acevedo, Brian T. Person, Joel A. Schmutz, Brian D. Uher-Koch, James S. Sedinger
2019, Article
Changes in ecological conditions can induce changes in behavior and demography of wild organisms, which in turn may influence population dynamics. Pacific black brant (Branta bernicla nigricans) nesting in colonies on the Yukon-Kuskokwim Delta (YKD) in western Alaska have declined substantially (~50%) since the turn of the century. Pacific black...
Holocene thermokarst lake dynamics in northern Interior Alaska: The interplay of climate, fire, and subsurface hydrology
Lesleigh Anderson, Mary E. Edwards, Mark D. Shapley, Bruce P. Finney, Catherine Langdon
2019, Frontiers in Earth Science (7) 1-22
The current state of permafrost in Alaska and meaningful expectations for its future evolution are informed by long-term perspectives of previous permafrost degradation. Thermokarst processes in permafrost landscapes often lead to widespread lake formation and the spatial and temporal evolution of thermokarst lake landscapes reflects the combined effects of climate,...
Energetic costs of aquatic locomotion in a subadult polar bear
Anthony M. Pagano, Amy Cutting, Nicole Nicassio-Hiskey, Amy Hash, Terrie M. Williams
2019, Marine Mammal Science (35) 649-659
Most marine mammals rely on swimming as their primary form of locomotion. These animals have evolved specialized morphologies, physiologies, and behaviors that have enabled them to efficiently move through an aquatic environment (Williams 1999). Such adaptations include body streamlining, modified plantar surfaces for propulsion, and abilities...
AVO-G2S: A modified, open-source Ground-to-Space atmospheric specification for infrasound modeling
Hans Schwaiger, Alexandra M. Iezzi, David Fee
2019, Computers & Geosciences (125) 90-97
To facilitate infrasound propagation studies, we present AVO-G2S, an open-source, Ground-to-Space model which provides temperature and wind specifications from the surface to an altitude of 225 km. This model provides a means of smoothly characterizing atmospheric conditions using multiple numerical weather prediction forecast and reanalysis products, along with upper-atmospheric...
Serologic evidence for influenza A virus exposure in three loon species (Gavia spp.) breeding in Alaska
Brian D. Uher-Koch, Timothy J. Spivey, Caroline R. Van Hemert, Joel A. Schmutz, Kaijun Jiang, Xiu-Feng Wan, Andrew M. Ramey
2019, Journal of Wildlife Diseases (55) 862-867
Limited information exists about exposure to influenza A viruses (IAVs) in many wild waterbird species, including loons. We analyzed serum samples from breeding adult Pacific (Gavia pacifica), Red-throated (Gavia stellata), and Yellow-billed (Gavia adamsii) loons sampled at three locations along the coast of Alaska, US from 2008 to 2017 to...
Assessing patterns of annual change to permafrost bluffs along the North Slope coast of Alaska using high-resolution imagery and elevation models
Ann E. Gibbs, Matt Nolan, Bruce M. Richmond, Alexander G. Snyder, Li Erikson
2019, Geomorphology (336) 152-164
Coastal permafrost bluffs at Barter Island, on the North Slope, Beaufort Sea Coast of Alaska are among the most rapidly eroding along Alaska’s coast, having retreated up to 132 m between 1955 and 2015. Here we quantify rates and patterns of change over a single year using very-high resolution orthophotomosaics...
Energy allocation and feeding ecology of juvenile chum salmon (Oncorhynchus keta) during transition from freshwater to saltwater
Sean E. Burril, Vanessa R. von Biela, Nicola Hillbruber, Christian E. Zimmerman
2019, Polar Biology (41) 1447-1461
Pacific salmon (Oncorhynchus spp.) populations near their northern range extent in the Arctic-Yukon-Kuskokwim region of Alaska have undergone major changes in population trajectory and illuminated the lack of basic information on juvenile ecology. This study fills information gaps on the early life history of chum salmon at northern latitudes. Energy...
Measurement of long-term channel change through repeated cross-section surveys at bridge crossings in Alaska
Karenth L. Dworsky, Jeffrey S. Conaway
2019, Open-File Report 2019-1028
The U.S. Geological Survey (USGS) has been working with Alaska Department of Transportation and Public Facilities (ADOT&PF) since 1993 to provide hydraulic assessments of scour for bridges throughout Alaska. The purpose of the program is to evaluate, monitor, and study streambed scour at bridges in Alaska; this includes surveying...
Parallel signatures of selection at genomic islands of divergence and the major histocompatibility complex in ecotypes of sockeye salmon across Alaska
Wesley Larson, Tyler H. Dann, Morten T. Limborg, Garrett J. McKinney, James E. Seeb, Lisa W. Seeb
2019, Molecular Ecology (28) 2254-2271
Understanding the genetic mechanisms that facilitate adaptive radiation is an important component of evolutionary biology. Here, we genotyped 82 neutral SNPs, seven SNPs in islands of divergence identified in a previous study (island SNPs), and a region of the major histocompatibility complex (MHC) in 32 populations of sockeye salmon to...