Stratigraphic and microfossil evidence for a 4500-year history of Cascadia subduction zone earthquakes and tsunamis at Yaquina River estuary, Oregon, USA
Nicholas A Graehl, Harvey M. Kelsey, Robert C. Witter, Eileen Hemphill-Haley, Simon E. Engelhart
2015, GSA Bulletin (127) 211-226
The Sallys Bend swamp and marsh area on the central Oregon coast onshore of the Cascadia subduction zone contains a sequence of buried coastal wetland soils that extends back ∼4500 yr B.P. The upper 10 of the 12 soils are represented in multiple cores. Each soil is abruptly overlain...
Low productivity of Chinook salmon strongly correlates with high summer stream discharge in two Alaskan rivers in the Yukon drainage
Jason R. Neuswanger, Mark S. Wipfli, Matthew J. Evenson, Nicholas F. Hughes, Amanda E. Rosenberger
2015, Canadian Journal of Fisheries and Aquatic Sciences (72) 1125-1137
Yukon River Chinook salmon (Oncorhynchus tshawytscha) populations are declining for unknown reasons, creating hardship for thousands of stakeholders in subsistence and commercial fisheries. An informed response to this crisis requires understanding the major sources of variation in Chinook salmon productivity. However, simple stock–recruitment models leave much of the variation in...
Ursus maritimus
Oystein Wiig, Steven C. Amstrup, Todd C. Atwood, Kristin L Kaidre, Nicholas J Lunn, Martyn E. Obbard, Eric V. Regehr, Gregory W. Thiemann
2015, Book chapter, The IUCN Red List of Threatened Species 2015
No abstract available....
Examining the utility of bulk otolith δ13C to describe diet in wild-caught black rockfish Sebastes melanops
Vanessa R. von Biela, Seth D. Newsome, Christian E. Zimmerman
2015, Aquatic Biology (23) 201-208
Otolith carbon isotope δ13C values may provide temporally resolved diet proxies in fish. If otolith δ13C values reflect diet, isotope values from recent otolith and muscle tissue should correlate and known ontogenetic diet shifts should be reflected in comparisons between otolith material deposited during different life history stages. We analyzed...
Provenance and detrital zircon geochronologic evolution of lower Brookian foreland basin deposits of the western Brooks Range, Alaska, and implications for early Brookian tectonism
Thomas E. Moore, Paul B. O’Sullivan, Christopher J. Potter, Raymond A. Donelick
2015, Geosphere (11) 93-122
The Upper Jurassic and Lower Cretaceous part of the Brookian sequence of northern Alaska consists of syntectonic deposits shed from the north-directed, early Brookian orogenic belt. We employ sandstone petrography, detrital zircon U-Pb age analysis, and zircon fission-track double-dating methods to investigate these deposits in a succession of thin...
Historic and Contemporary Status of Sea Otters in the North Pacific
James L. Bodkin
Shawn E. Larson, Arthur Gross, Glenn R. VanBlaricom, editor(s)
2015, Book chapter, Sea Otter Conservation
Similar to other species that in recent centuries experienced unregulated human exploitation, sea otters were extirpated throughout large portions of their historic range in the North Pacific. For most of the twentieth century, with cessation of the fur trade and because of concerted efforts at conservation, sea otters recovered much...
From icefield to ocean - Explore the many ways that glaciers influence Alaska's Coastal Ecosystems.
Shad O’Neel, Eran Hood, Kristin Timm
2015, Report
No abstract available....
Sensitivity of tsunami evacuation modeling to direction and land cover assumptions
Mathew C. Schmidtlein, Nathan J. Wood
2015, Applied Geography (56) 154-163
Although anisotropic least-cost-distance (LCD) modeling is becoming a common tool for estimating pedestrian-evacuation travel times out of tsunami hazard zones, there has been insufficient attention paid to understanding model sensitivity behind the estimates. To support tsunami risk-reduction planning, we explore two aspects of LCD modeling as it applies to pedestrian...
Testing the nutritional-limitation, predator-avoidance, and storm-avoidance hypotheses for restricted sea otter habitat use in the Aleutian Islands, Alaska
Nathan L. Stewart, Brenda Konar, M. Tim Tinker
2015, Oecologia (177) 645-655
Sea otters (Enhydra lutris) inhabiting the Aleutian Islands have stabilized at low abundance levels following a decline and currently exhibit restricted habitat-utilization patterns. Possible explanations for restricted habitat use by sea otters can be classified into two fundamentally different processes, bottom-up and top-down forcing. Bottom-up hypotheses argue that changes in the...
Pronounced chemical response of Subarctic lakes to climate-driven losses in surface area
Tyler L. Lewis, Mark S. Lindberg, Joel A. Schmutz, Patricia J. Heglund, Jennifer R. Rover, Joshua C. Koch, Mark R. Bertram
2015, Global Change Biology (21) 1140-1152
Losses in lake area have been observed for several Arctic and Subarctic regions in recent decades, with unknown consequences for lake ecosystems. These reductions are primarily attributed to two climate-sensitive mechanisms, both of which may also cause changes in water chemistry: (i) increased imbalance of evaporation relative to inflow, whereby...
The 3D Elevation Program: summary for Wyoming
William J. Carswell Jr.
2015, Fact Sheet 2014-3108
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 Wyoming, elevation data are critical for geologic resource assessment and hazard mitigation, flood risk management, water supply an quality, natural resources conservation,...
Spatiotemporal variation of surface shortwave forcing from fire-induced albedo change in interior Alaska
Shengli Huang, Devendra Dahal, Heping Liu, Suming Jin, Claudia J. Young, Shuang Liu, Shu-Guang Liu
2015, Canadian Journal of Forest Research (45) 276-285
The albedo change caused by both fires and subsequent succession is spatially heterogeneous, leading to the need to assess the spatiotemporal variation of surface shortwave forcing (SSF) as a component to quantify the climate impacts of high-latitude fires. We used an image reconstruction approach to compare postfire albedo with the...
Testing the use of bulk organic δ13C, δ15N, and Corg:Ntot ratios to estimate subsidence during the 1964 great Alaska earthquake
Adrian M. Bender, Robert C. Witter, Matthew Rogers
2015, Quaternary Science Reviews (113) 134-146
During the Mw 9.2 1964 great Alaska earthquake, Turnagain Arm near Girdwood, Alaska subsided 1.7 ± 0.1 m based on pre- and postearthquake leveling. The coseismic subsidence in 1964 caused equivalent sudden relative sea-level (RSL) rise that is stratigraphically preserved as mud-over-peat contacts where intertidal silt buried peaty marsh surfaces. Changes in intertidal microfossil...
Permafrost-associated gas hydrate: is it really approximately 1% of the global system?
Carolyn Ruppel
2015, Journal of Chemical & Engineering Data (60) 429-436
Permafrost-associated gas hydrates are often assumed to contain ∼1 % of the global gas-in-place in gas hydrates based on a study26 published over three decades ago. As knowledge of permafrost-associated gas hydrates has grown, it has become clear that many permafrost-associated gas hydrates are inextricably linked to an associated conventional...
Demography of the Pacific walrus (Odobenus rosmarus divergens): 1974-2006
Rebecca L. Taylor, Mark S. Udevitz
2015, Marine Mammal Science (31) 231-254
Global climate change may fundamentally alter population dynamics of many species for which baseline population parameter estimates are imprecise or lacking. Historically, the Pacific walrus is thought to have been limited by harvest, but it may become limited by global warming-induced reductions in sea ice. Loss of sea ice, on...
Variations in population vulnerability to tectonic and landslide-related tsunami hazards in Alaska
Nathan J. Wood, Jeff Peters
2015, Natural Hazards (75) 1811-1831
Effective tsunami risk reduction requires an understanding of how at-risk populations are specifically vulnerable to tsunami threats. Vulnerability assessments primarily have been based on single hazard zones, even though a coastal community may be threatened by multiple tsunami sources that vary locally in terms of inundation extents and wave arrival...
Introduced northern pike consumption of salmonids in Southcentral Alaska
Adam Sepulveda, David S. Rutz, Aaron W Dupuis, Patrick A Shields, Kristine J. Dunker
2015, Ecology of Freshwater Fish (24) 519-531
The impacts of introduced northern pike (Esox lucius) on salmonid populations have attracted much attention because salmonids are popular subsistence, sport and commercial fish. Concern over the predatory effects of introduced pike on salmonids is especially high in Southcentral Alaska, where pike were illegally introduced to the Susitna River basin...
The conservation of sea otters: a prelude
James L. Bodkin, Shawn E. Larson
2015, Book chapter, Sea Otter Conservation
The story of sea otters over the past 275 years chronicles their decline to near extinction and the roads to recovery that cross various conflicts, and in the end provides lessons that will aid the conservation of other threatened species and compromised ecosystems. Sea otters inspire strong human emotions ranging...
Brood rearing ecology of King Eiders breeding on the North Slope of Alaska
Laura M. Phillips, Abby N. Powell
2015, Wilson Journal of Ornithology (121) 430-434
Influences of glacial melt and permafrost thaw on the age of dissolved organic carbon in the Yukon River basin
George R. Aiken, Robert G.M. Spencer, Robert G. Striegl, Paul F. Schuster, Peter A. Raymond
2014, Global Biogeochemical Cycles (28) 525-537
Responses of near-surface permafrost and glacial ice to climate change are of particular significance for understanding long-term effects on global carbon cycling and carbon export by high-latitude northern rivers. Here we report Δ14C-dissolved organic carbon (DOC) values and dissolved organic matter optical data for the Yukon River, 15...
Prevalence of pure versus mixed snow cover pixels across spatial resolutions in alpine environments: implications for binary and fractional remote sensing approaches
David J. Selkowitz, Richard Forster, Megan K. Caldwell
2014, Remote Sensing (6) 12478-12508
Remote sensing of snow-covered area (SCA) can be binary (indicating the presence/absence of snow cover at each pixel) or fractional (indicating the fraction of each pixel covered by snow). Fractional SCA mapping provides more information than binary SCA, but is more difficult to implement and may not be feasible with...
A reply to Jepsen, N., K. Aarestrup and S.J. Cooke. Tagging fish in the field: ethical and procedural considerations. A comment to the recent paper of D. Mulcahy; Legal, ethical and procedural bases for the use of aseptic techniques to implant electronic devices, ( Journal of Fish and Wildlife Management 4: 211–219)
Daniel M. Mulcahy
2014, Journal of Fish and Wildlife Management (5) 445-449
Effects of invasive European bird cherry (Prunus padus) on leaf litter processing by aquatic invertebrate shredder communities in urban Alaskan streams
David A. Roon, Mark S. Wipfli, Tricia L. Wurtz
2014, Hydrobiologia (736) 17-30
European bird cherry (Prunus padus) (EBC) is an invasive ornamental tree that is spreading rapidly in riparian forests of urban Alaska. To determine how the spread of EBC affects leaf litter processing by aquatic invertebrate shredders, we conducted complementary leaf pack experiments in two streams located in Anchorage, Alaska. The...
Wildlife health in a rapidly changing North: focus on avian disease
Caroline R. Van Hemert, John M. Pearce, Colleen M. Handel
2014, Frontiers in Ecology and the Environment (12) 548-556
Climate-related environmental changes have increasingly been linked to emerging infectious diseases in wildlife. The Arctic is facing a major ecological transition that is expected to substantially affect animal and human health. Changes in phenology or environmental conditions that result from climate warming may promote novel species assemblages as host and...
The 2010 slow slip event and secular motion at Kilauea, Hawai`i inferred from TerraSAR-X InSAR data
Jingyi Chen, Howard A. Zebker, Paul Segall, Asta Miklius
2014, Journal of Geophysical Research B: Solid Earth (119) 6667-6683
We present here an Small BAseline Subset (SBAS) algorithm to extract both transient and secular ground deformations on the order of millimeters in the presence of tropospheric noise on the order of centimeters, when the transient is of short duration and known time, and the background deformation is smooth in...
