Biological correlates of sea urchin recruitment in kelp forest and urchin barren habitats
Ben Weitzman, Brenda H. Konar
2021, Marine Ecology Progress Series (663) 115-125
Shifts between the alternate stable states of sea urchin barren grounds and kelp forests correspond to sea urchin density. In the Aleutian Archipelago, green sea urchins Strongylocentrotus polyacanthus are the dominant herbivores that graze kelp forests. Sea urchin recruitment is an important driver that influences sea urchin density, particularly in the absence...
Glacial dust surpasses both volcanic ash and desert dust in its iron fertilization potential
Bess G. Koffman, Meg F. Yoder, Taylor Methven, Lena Hanschka, Helen B. Sears, Patrick L. Saylor, Kristi L. Wallace
2021, Global Biogeochemical Cycles (35)
The subarctic Pacific Ocean and Bering Sea comprise the second-largest high nitrate, low chlorophyll region in the world, where primary production is limited by the availability of iron (Fe). To estimate the potential impact of different terrestrial aerosol Fe sources on marine ecosystems, we performed a suite of laboratory assessments...
U.S. Geological Survey Arctic ecosystem assessments
John M. Pearce, Caroline R. Van Hemert
2021, Fact Sheet 2021-3016
The U.S Geological Survey (USGS) conducts natural hazard and resource assessments of the Earth’s ecosystems and the response of those ecosystems to environmental change, human activities, and land use. Arctic regions of Alaska are important for cultural and economic sustainability and host a wide variety of wildlife species, many of...
Investigation of algal toxins in a multispecies seabird die-off in the Bering and Chukchi seas
Caroline R. Van Hemert, Robert J. Dusek, Matthew M. Smith, Robert Kaler, Gay Sheffield, Lauren M. Divine, Kathy J. Kuletz, Susan Knowles, Julia S. Lankton, D. Ransom Hardison, R. Wayne Litaker, Timothy Jones, Hillary K. Burgess, Julia K. Parrish
2021, Journal of Wildlife Diseases (57) 399-407
Between 2014 and 2017, widespread seabird mortality events were documented annually in the Bering and Chukchi seas, concurrent with dramatic reductions of sea ice, warmer than average ocean temperatures, and rapid shifts in marine ecosystems. Among other changes in the marine environment, harmful algal blooms (HABs) that produce the neurotoxins...
Dating fault damage along the eastern Denali fault zone with hematite (U-Th)/He thermochronometry
Robert G. McDermott, Alexis K. Ault, Jonathan Caine
2021, Earth and Planetary Science Letters (563)
Unraveling complex slip histories in fault damage zones to understand relations among deformation, hydrothermal alteration, and surface uplift remains a challenge. The dextral eastern Denali fault zone (EDFZ; southwest Yukon, Canada) bounds the Kluane Ranges and hosts a variety of fault-related rocks, including hematite fault surfaces, which have been exhumed...
Whole‐genome resequencing reveals persistence of forest‐associated mammals in Late Pleistocene refugia along North America’s North Pacific Coast
Jocelyn P. Colella, Tianying Lan, Sandra L. Talbot, Charlotte Lindqvist, Joseph A. Cook
2021, Journal of Biogeography (48) 1153-1169
AimNumerous glacial refugia have been hypothesized along North America's North Pacific Coast that may have increased divergence of refugial taxa, leading to elevated endemism and subsequently clustered hybrid zones following deglaciation. The locations and community composition of these ice‐free areas remains controversial, but whole‐genome sequences now enable...
Ecosystem response persists after a prolonged marine heatwave
Robert M. Suryan, Mayumi L. Arimitsu, Heather A. Coletti, Russell R. Hopcroft, Mandy Lindeberg, Steven J. Barbeaux, Sonia Batten, William J. Burt, Mary Anne Bishop, James L. Bodkin, R. Brenner, Robert W. Campbell, Daniel A. Cushing, Seth L. Danielson, Martin W. Dorn, Brie Drummond, Daniel Esler, Thomas S. Gelatt, Dana H. Hanselman, Katrin Iken, David B. Irons, Scott A. Hatch, Stormy Haught, Kris Holderied, David G. Kimmel, Brenda H. Konar, Kathy J. Kuletz, Arthur B. Kettle, Benjamin J. Laurel, John M. Maniscalco, Daniel Monson, Craig O. Matkin, Caitlin McKinstry, John Moran, D. Olsen, John F. Piatt, Wayne A. Palsson, W. Scott Pegau, Lauren A. Rogers, Nora A. Rojek, Anne Schaefer, Ingrid B. Spies, J.M. Straley, Suzanne L. Strom, Marysia Szymkowiak, Kathryn L. Sweeney, Ben P. Weitzman, Ellen M. Yasumiishi, Stephanie Zador
2021, Scientific Reports (11)
Some of the longest and most comprehensive marine ecosystem monitoring programs were established in the Gulf of Alaska following the environmental disaster of the Exxon Valdez oil spill over 30 years ago. These monitoring programs have been successful in assessing recovery from oil spill impacts, and their continuation decades later has now provided...
U.S. Geological Survey—Department of the Interior Region 11, Alaska —2020 annual science report
Elizabeth M. Powers, Dee M. Williams, editor(s)
2021, Open-File Report 2021-1010
U.S. Geological Survey (USGS) Mission: The USGS national mission is to monitor, analyze, and predict current and evolving dynamics of complex human and natural Earth-system interactions and to deliver actionable information at scales and timeframes relevant to decision-makers. Consistent with the national mission, the USGS in Alaska provides...
Determinants of gray wolf (Canis lupus) sightings in Denali National Park
Bridget L. Borg, Stephen M. Arthur, Jeffrey A. Falke, Laura R. Prugh
2021, Arctic (74) 51-66
Wildlife viewing within protected areas is an increasingly popular recreational activity. Management agencies are often tasked with providing these opportunities, yet quantitative analyses of factors influencing wildlife sightings are lacking. We analyzed locations of GPS-collared wolves and wolf sightings from 2945 trips in Denali National Park and Preserve, Alaska, USA,...
Using bottom trawls to monitor subsurface water clarity in marine ecosystems
Sean K. Rohan, Stan Kotwicki, Kelly A. Kearney, Jennifer A Schulien, Edward A. Laman, Edward D. Cokelet, David Beauchamp, Lyle L. Britt, Kerim Y. Aydin, Stephani G. Zador
2021, Progress in Oceanography (194)
Biophysical processes that affect subsurface water clarity play a key role in ecosystem function. However, subsurface water clarity is poorly monitored in marine ecosystems because doing so requires in-situ sampling that is logistically difficult to conduct and sustain. Novel solutions are...
Extending seasonal discharge records for streamgage sites on the North Fork Fortymile and Middle Fork Fortymile Rivers, Alaska, through water year 2020
Janet H. Curran
2021, Scientific Investigations Report 2021-5014
Daily mean discharge records are needed for management of selected streams in the Fortymile River Basin. The U.S. Geological Survey, in cooperation with the U.S. Bureau of Land Management, updated a technique for estimating seasonal (partial year) discharge at two short-record streamgage sites in the basin and evaluated the...
Reduced quality and synchronous collapse of forage species disrupts trophic transfer during a prolonged marine heatwave
Mayumi L. Arimitsu, John F. Piatt, Scott Hatch, Rob Suryan, Sonia Batten, Mary Anne Bishop, Rob Campbell, Heather Coletti, Dan Cushing, Kristen Gorman, Stormy Haught, Russell Hopcroft, Kathy Kuletz, Caitlin Elizabeth Marsteller, Caitlin McKinstry, David McGowan, John Moran, R. Scott Pegau, Anne Schaefer, Sarah K. Schoen, Jan Straley, Vanessa R. von Biela
2021, Book chapter, The Pacific marine heatwave: Monotoring during a major perturbation in the Gulf of Alaska
The Gulf of Alaska forage fish community includes a few key species that differ markedly in their timing of spawning, somatic growth and lipid storage, and in their migration behavior. This diversity in life history strategies facilitates resilience in marine food webs because it buffers predators against the naturally high...
A study of marine temperature variations in the northern Gulf of Alaska across years of marine heatwaves and cold spells
Seth L. Danielson, Tyler D. Hennon, Daniel Monson, Rob M. Suryan, Rob W. Campbell, Steven J. Baird, Kristine Holderied, Thomas Weingartner
2021, Report, The Pacific marine heatwave: Monotoring during a major perturbation in the Gulf of Alaska
We use over 100 in situ and remotely sensed temperature datasets to investigate thermal variability within and across the intertidal nearshore, coastal and offshore waters of the northern Gulf of Alaska. For the years 1970 through 2019 we document a warming trend of 0.24±0.10 °C per decade for the coastal...
Genomic comparison of carbapenem-resistant Enterobacteriaceae from humans and gulls in Alaska
Christina Ahlstrom, Anna Frick, Catherine Pongratz, Kimberly Spink, Catherine Xavier, Jonas Bonnedahl, Andrew M. Ramey
2021, Journal of Global Antimicrobial Resistance (25) 23-25
ObjectivesWildlife may harbor clinically important antimicrobial resistant (AMR) bacteria, but the role of wildlife in the epidemiology of AMR bacterial infections in humans is largely unknown. In this study, we aimed to assess dissemination of theblaKPC carbapenemase gene among humans and gulls in Alaska.<h3...
Seal body condition and atmospheric circulation patterns influence polar bear body condition, recruitment, and feeding ecology in the Chukchi Sea
Karyn D. Rode, Eric V. Regehr, Jeffrey F. Bromaghin, Ryan H. Wilson, Michelle St. Martin, Justin A. Crawford, Lori T. Quakenbush
2021, Global Change Biology (27) 2684-2701
Polar bears (Ursus maritimus) are experiencing loss of sea ice habitats used to access their marine mammal prey. Simultaneously, ocean warming is changing ecosystems that support marine mammal populations. The interactive effects of sea ice and prey are not well understood yet may explain spatial‐temporal variation in the response of...
Response of an asymmetrical five-story building in Fairbanks, Alaska during the November 30, 2018 M7.1 Anchorage, Alaska earthquake
Mehmet Çelebi, Natalia Ruppert
2021, Report
A recently constructed, five-story, asymmetrical steel building on the campus of the University of Alaska, Fairbanks was equipped with a strong-motion array that recorded the M7.1 Anchorage earthquake of November 30, 2018 at an epicentral distance of 408 km. The largest recorded peak accelerations at...
U–Pb zircon eruption age of the Old Crow tephra and review of extant age constraints
Seth D. Burgess, Jorge A. Vazquez, Christopher F. Waythomas, Kristi L. Wallace
2021, Quaternary Geochronology (66)
Eruption of the Old Crow tephra deposited ~200 km3 of volcanic ash throughout Alaska and the northwestern Yukon (eastern Beringia), providing an isochronous marker across the region on a scale unique in the Pleistocene. The Old Crow tephra represents a critical temporal piercing point used...
Eruption of compositionally heterogeneous andesites from a complex storage region during the 2006 eruption of Augustine Volcano
Mary Catherine Benage, Heather M. Wright, Michelle L. Coombs
2021, Bulletin of Volcanology (83)
Despite the common occurrence of heterogeneous andesitic eruptions, few studies have investigated the compositional effects on microlite crystallization and vesiculation in co-erupted natural samples. In 2006, Augustine Volcano erupted compositionally heterogeneous andesites that range from 56.4 to 63.3 wt% SiO2 and include two endmember lithologic groups: low-silica andesite (LSA) and high-silica andesite...
Subducting oceanic basement roughness impacts on upper plate tectonic structure and a backstop splay fault zone activated in the southern Kodiak aftershock region of the Mw 9.2, 1964 megathrust rupture, Alaska
Anne Krabbenhoeft, Roland E. von Huene, John J. Miller, Dirk Klaeschen
2021, Geosphere (17) 409-437
In 1964, the Alaska margin ruptured in a giant Mw 9.2 megathrust earthquake, the 2nd largest during worldwide instrumental recording. The coseismic slip and aftershock region offshore Kodiak Island was surveyed in 1977 – 1981 to understand the region’s tectonics. We re-processed multichannel seismic (MCS) field data using current standard...
Implications of historical and contemporary processes on genetic differentiation of a declining boreal songbird: The rusty blackbird
Robert E. Wilson, Steven M. Matsuoka, Luke L. Powell, James A. Johnson, Dean W. Demarest, Diana Stralberg, Sarah A. Sonsthagen
2021, Diversity (13)
The arrangement of habitat features via historical or contemporary events can strongly influence genomic and demographic connectivity, and in turn affect levels of genetic diversity and resilience of populations to environmental perturbation. The rusty blackbird (Euphagus carolinus) is a forested wetland habitat specialist whose population size...
Geochemical advances in Arctic Alaska oil typing - North Slope oil correlation and charge history
Palma J. Botterell, David W. Houseknecht, Paul G. Lillis, Silvana M. Barbanti, Jeremy E. Dahl, J. Michael Moldowan
2021, Marine and Petroleum Geology (127)
The Arctic Alaska petroleum province is geologically and geochemically complex. Mixed hydrocarbon charge from multiple source rocks and/or levels of thermal maturity is common within an individual oil pool. Biomarker and chemometric statistical analyses were used to correlate twenty-nine oils to five oil families derived from: (1) Triassic Shublik Formation (calcareous...
Decadal-scale hotspot methane ebullition within lakes following abrupt permafrost thaw
K.W. Anthony, P. Lindgren, P. Hanke, M. Engram, P. Anthony, R. Daanen, A. Bondurant, A.K. Liljedahl, J. Lenz, G. Grosse, B.M. Jones, L. S. Brosius, Stephanie R. James, Burke J. Minsley, Neal Pastick, J. Munk, J. P. Chanton, C.E. Miller, F.J. Meyer
2021, Environmental Research Letters (16)
Thermokarst lakes accelerate deep permafrost thaw and the mobilization of previously frozen soil organic carbon. This leads to microbial decomposition and large releases of carbon dioxide (CO2) and methane (CH4) that enhance climate warming. However, the time scale of permafrost-carbon emissions following thaw is not well known...
Extreme Quaternary plate boundary exhumation and strike slip localized along the southern Fairweather fault, Alaska, USA
Richard O. Lease, Peter J. Haeussler, Robert C. Witter, Daniel F. Stockli, Adrian Bender, Harvey Kelsey, Paul O'Sullivan
2021, Geology (49) 602-606
The Fairweather fault (southeastern Alaska, USA) is Earth’s fastest-slipping intracontinental strike-slip fault, but its long-term role in localizing Yakutat–(Pacific–)North America plate motion is poorly constrained. This plate boundary fault transitions northward from pure strike slip to transpression where it comes onshore and undergoes a <25°, 30-km-long restraining double bend. To...
Local explosion detection and infrasound localization by reverse time migration using 3-D finite-difference wave propagation
David Fee, Liam Toney, Keehoon Kim, Richard Sanderson, Alexandra M. Iezzi, Robin S Matoza, Silvio DeAngelis, Art Jolly, John J. Lyons, Matthew M. Haney
2021, Frontiers in Earth Science (9)
Infrasound data are routinely used to detect and locate volcanic and other explosions, using both arrays and single sensor networks. However, at local distances (<15 km) topography often complicates acoustic propagation, resulting in inaccurate acoustic travel times leading to biased source locations when assuming straight-line propagation. Here we...
The imminent calving retreat of Taku Glacier
Christopher J. McNeil, Jason Amundson, Shad O'Neel, Roman Motyka, Louis C. Sass, Martin Truffer, Jenna Ziemann, Seth Campbell
2021, Eos, American Geophysical Union
Along the rugged Southeast Alaska coast, 30 kilometers northeast of the state capital Juneau, a tidewater glacier has largely defied global trends by steadily advancing for most of the past century while most glaciers on Earth retreated. This 55-kilometer-long and nearly 1,500-meter-thick tidewater glacier, named Taku Glacier, or T'aaḵú Ḵwáan Sít'i in...
