A generalized framework for inferring river bathymetry from image-derived velocity fields
Carl J. Legleiter, Paul J. Kinzel
2025, Geomorphology (479)
Although established techniques for remote sensing of river bathymetry perform poorly in turbid water, image velocimetry can be effective under these conditions. This study describes a framework for mapping both of these attributes: Depths Inferred from Velocities Estimated by Remote Sensing, or DIVERS. The workflow involves linking image-derived velocities to...
Critical Minerals in Ores (CMiO) database
George N. D. Case, Garth E. Graham, Christopher Lawley, Evgeniy Bastrakov, David Huston, Albert H. Hofstra, Vladimir Lisitsin, Steph Hawkins, Bronwen Wang
2025, Fact Sheet 2025-3002
Critical minerals are commodities essential to modern industrial and strategic technologies and are highly vulnerable to supply chain disruption. The Critical Minerals Mapping Initiative (CMMI) is a collaboration among the U.S. Geological Survey (USGS), the Geological Survey of Canada, and Geoscience Australia that aims to deepen global understanding of where...
Shortening migration by 4500 km does not affect nesting phenology or increase nest success for black brant (Branta bernicla nigricans) breeding in Arctic and subarctic Alaska
Toshio Doroff Matsuoka, Vijay P. Patil, Jerry W. Hupp, Alan G. Leach, John Reed, James S. Sedinger, David H. Ward
2025, Movement Ecology (13)
BackgroundSince the 1980s, Pacific Black Brant (Branta bernicla nigricans, hereafter brant) have shifted their winter distribution northward from Mexico to Alaska (approximately 4500 km) with changes in climate. Alongside this shift, the primary breeding population of brant has declined. To understand the population-level implications of the changing migration strategy...
Reconstruction of Holocene and Last Interglacial vegetation dynamics and wildfire activity in Southern Siberia
Jade Margerum, Julia Homann, Stuart Umbo, Gernot Nehrke, Thorsten Hoffmann, Anton Vaks, Aleksandr Kononov, Alexander Osintsev, Alena Maria Giesche, Andrew Mason, Franziska A. Lechleitner, Gideon M. Henderson, Ola Kwiecien, Sebastian F.M. Breitenbach
2025, Climate of the Past (21) 661-677
Wildfires are a rapidly increasing threat to boreal forests. While our understanding of the drivers behind wildfires and their environmental impact is growing, it is mostly limited to the observational period. Here we focus on the boreal forests of southern Siberia and exploit a U–Th-dated stalagmite from Botovskaya Cave, located...
United States Register of Introduced and Invasive Species
Annie Simpson, Mark T. Wiltermuth, Mireya Dorado
2025, Fact Sheet 2024-3037
The pervasive and insidious threat of invasive species costs the United States more than $120 billion, annually. An invasive species is an organism that is not native to a locality and causes (or is likely to cause) harm. An introduced species is one that is nonnative to a locality and...
A 700-year rupture sequence of great eastern Aleutian earthquakes from tsunami modeling of stratigraphic records
Yoshiki Yamazaki, Kwok Fai Cheung, Thorne Lay, SeanPaul La Selle, Robert C. Witter, Bruce E. Jaffe
2025, Nature Communications (16)
Great Aleutian underthrusting earthquakes produced destructive tsunamis impacting Hawaiʻi in 1946 and 1957. Prior modeling of the 1957 tsunami deposit and runup records on eastern Aleutian and Hawaiian Islands jointly with tide-gauge observations across the Pacific Ocean constrained a rupture model with shallow slip up to 26 m along 600 km of...
Exposure of wild mammals inhabiting Alaska to influenza A(H5N1) virus
Andrew M. Ramey, Kimberlee B. Beckmen, David T. Saafeld, Kerry Nicholson, Buck A. Mangipane, Laura Celeste Scott, David E. Stallknecht, Rebecca L. Poulson
2025, Emerging Infectious Diseases (31) 804-808
Serum samples from wild mammals inhabiting Alaska, USA, showed that 4 species, including Ursus arctos bears and Vulpes vulpes foxes, were exposed to influenza A(H5N1) viruses. Results indicated some mammals in Alaska survived H5N1 virus infection. Surveillance efforts may be improved by incorporating information on susceptibility and detectable immune responses among wild mammals....
Delineating ecologically-distinct groups for annual cycle management of a declining shorebird
Elly C. Knight, J. D. Carlisle, Andy J. Boyce, D.C. Bradley, Paula Cimprich, Stephanie Coates, Stephen J. Dinsmore, Cory J. Gregory, Joel G. Jorgensen, Jeffrey F. Kelly, David Newstead, Alina Olalla, Larkin A. Powell, Amy L. Scarpignato, T. Lee Tibbitts, Nils Warnock, Walter Wehtje, Peter P. Marra, Autumn-Lynn Harrison
2025, Journal of Applied Ecology (62) 1152-1165
1. Patterns of migratory connectivity are increasingly used to understand and manage threats throughout the annual cycle of migratory species. Strong migratory connectivity refers to when individuals from different populations remain spatially separated across the annual cycle, which may expose populations to unique sets of threats and conditions that cause...
Measuring polar bear health using allostatic load
Sarah Teman, Todd C. Atwood, Sarah J. Converse, Tricia Fry, Kristin L. Laidre
2025, Conservation Physiology (13)
The southern Beaufort Sea polar bear sub-population (Ursus maritimus) has been adversely affected by climate change and loss of sea ice habitat. Even though the sub-population is likely decreasing, it remains difficult to link individual polar bear health and physiological change to sub-population effects. We developed an index of allostatic...
Estimating spatially explicit survival and mortality risk from telemetry data with thinned point process models
Joseph Michael Eisaguirre, Medeleine G. Lohman, Graham G. Frye, Heather E. Johnson, Thomas V. Riecke, Perry J. Williams
2025, Ecology Letters (28)
Mortality risk for animals often varies spatially and can be linked to how animals use landscapes. While numerous studies collect telemetry data on animals, the focus is typically on the period when animals are alive, even though there is important information that could be gleaned about mortality risk. We introduce...
Mount Spurr Volcano
Kristi L. Wallace, Christopher F. Waythomas, Michelle L. Coombs, A.M. Nastan
2025, Alaska Division of Geological & Geophysical Surveys Information Circular 98
No abstract available....
A practical decision tool for marine bird mortality assessments
Johanna Alexandra Harvey, Andrew M. Ramey, Stephanie Avery-Gomm, Gregory Robertson, Marc Romano, Jennifer M. Mullinax, Megan Boldenow, Philip W. Atkinson, Diann Prosser
2025, Preprint
Given the rise in anthropogenic, environmental, and disease events contributing to marine bird mortality, there is a critical need to improve the rigor of mortality assessments. Deficits in data collection and mortality estimation can hinder a manager’s ability to document event scales and inform population level impacts. Therefore, to inform...
Phase 1 technical implementation plan for the expansion of the ShakeAlert earthquake early warning system to Alaska
Cecily J. Wolfe, Natalia A. Ruppert, Douglas D. Given, Michael E. West, Valerie Thomas, Jessica R. Murray, Ronni Grapenthin
2025, Open-File Report 2025-1003
Executive SummaryThe conference report accompanying the fiscal year (FY) 2022 Consolidated Appropriations Act (Public Law 117–103) for the U.S. Department of the Interior and related agencies directed the U.S. Geological Survey (USGS) to “work with the State of Alaska to develop an implementation plan to be completed within two years...
Did the Aleutian Basin form by plate capture or backarc basin opening?
Robert J. Stern, David W. Scholl, Matthew A. Malkowski, Kylara M. Martin, Ginger Barth, Daniel S. Scheirer
2025, International Geology Review (67) 1697-1719
The origin of the Aleutian Basin is unresolved because its crust is deeply buried beneath sediments. It has been interpreted as forming in the Eocene when the Beringian convergent margin jumped seaward to south of the Aleutian arc, thereby capturing a large sector of Cretaceous Pacific crust. Alternatively, it may...
Apatite geo-thermochronology and geochemistry constrain Oligocene-Miocene growth and geodynamics of the northeastern Tibetan Plateau
Chao Guo, Zhiyong Zhang, Richard O. Lease, Marco Malusa, David Chew, Haijian Lu, Lin Wu, Dunfeng Xiang, Nan Wang, Bernhard Grasemann, Wenjiao Xiao
2025, Geophysical Research Letters (52)
Understanding the geodynamics of plateau evolution requires examining the spatial and temporal aspects of mountain building in the northeastern Tibetan Plateau, which are still under debate. Here we integrate apatite geo-thermochronological and geochemical data from the Oligocene-Miocene succession of the Xunhua Basin to elucidate the evolution of the regional topography....
Developing a probabilistic tsunami hazard assessment framework for Pacific sources: USGS Powell Center meeting summary
Jason R. Patton, Stephanie L Ross, Marie C. Eble, Christodoulos Kyriakopoulos, Patrick J. Lynett, DmitriyJ. Nicolsky, Kenneth Ryan, Hong Kie Thio, Rick I. Wilson, Baoning Wu
2025, Environmental & Engineering Geoscience (31) 67-76
Multi-organizational principal investigators formed a U.S. Geological Survey (USGS) Powell Center Working Group (WG), Tsunami Source Standardization for Hazards Mitigation in the United States, to develop a comprehensive series of sources capable of generating tsunamis that could impact U.S. state and territory coastal areas using probabilistic tsunami hazard analysis (PTHA)....
An unexplained tsunami: Was there megathrust slip during the 2020 Mw7.6 Sand Point, Alaska, earthquake?
Sean R. Santellanes, Dara Elyse Goldberg, Pablo Koch, Diego Melgar, William L. Yeck, Brendan W. Crowell, Jiun-Ting Lin
2025, Seismica (4) 1-13
On October 19, 2020, the Mw7.6 Sand Point earthquake struck south of the Shumagin Islands in Alaska. Moment tensors indicate the earthquake was primarily strike-slip, yet the event produced an enigmatic tsunami that was larger and more widespread than expected for an earthquake of that magnitude and mechanism. Using a...
A fire deficit persists across diverse North American forests despite recent increases in area burned
Sean Parks, Chris Guiterman, Ellis Margolis, Maggie Lonergan, Ellen Whitman, John T. Abatzoglou, Donald A. Falk, James B. Johnston , Lori D. Daniels, Charles W. Lafon, Rachel A. Loehman, Kurt F. Kipfmueller, Cameron E. Naficy, Marc-Andre Parisien, Jeanne Portier, Michael C. Stambaugh, A. Park Williams, Andreas Paul Wion, Larissa Yocom
2025, Nature Communications (16)
Rapid increases in wildfire area burned across North American forests pose novel challenges for managers and society. Increasing area burned raises questions about whether, and to what degree, contemporary fire regimes (1984–2022) are still departed from historical fire regimes (pre-1880). We use the North American tree-ring fire-scar network (NAFSN), a...
Bait trapping of waterfowl increases the environmental contamination of avian influenza virus (AIV)
Cassandra Andrew, Landon McPhee, Kevin Kuchinski, Jordan Wight, Ishraq Rahman, Sarah Mansour, Gabrielle Angelo Cortez, Marzieh Kalhor, Ethan Kenmuir, Natalie Prystajecky, Kathryn Hargan, Andrew Lang, James Leafloor, Catherine Soos, Andrew M. Ramey, Chelsea Himsworth
2025, Journal of Wildlife Management (89)
Highly pathogenic avian influenza virus (HPAIV) H5Nx clade 2.3.4.4b has circulated in North America since late 2021, resulting in higher rates of morbidity and mortality in wild birds than observed in this region before. The objective of this study was to determine whether baiting, which is widely conducted in Canada...
2022 Volcanic activity in Alaska and the Northern Mariana Islands—Summary of events and response of the Alaska Volcano Observatory
Tim R. Orr, Hannah R. Dietterich, Ronni Grapenthin, Matthew M. Haney, Matthew W. Loewen, Pablo Saunders-Shultz, Darren Tan, Christopher F. Waythomas, Aaron G. Wech
2025, Scientific Investigations Report 2024-5108
In 2022, the Alaska Volcano Observatory responded to eruptions, volcanic unrest or suspected unrest, increased seismicity, and other significant activity at 11 volcanic centers in Alaska and in the Northern Mariana Islands. Eruptive activity in Alaska consisted of repeated small, ash-producing, phreatomagmatic explosions from Mount Young on Semisopochnoi Island; the...
Forecasting sea otter recolonization: Insights from isotopic analysis of modern and zooarchaeological populations
Emma A. Elliott Smith, Madonna L. Moss, Hannah P. Wellman, Verena A. Gill, Daniel Monson, Seth D. Newsome
2025, Proceedings of the Royal Society B, Biological Sciences (292)
Retrospective datasets offer essential context for conservation by revealing species’ ecological roles before industrial-era human impacts. We analysed isotopic compositions of pre-industrial and modern sea otters (Enhydra lutris) to reconstruct pre-extirpation ecology and offer insights for management. Our study focuses on southeast Alaska (SEAK), where sea otters are recolonizing, and...
The importance of method selection when estimating diet composition with quantitative fatty acid signature analysis
Jeffrey F. Bromaghin, Todd C. Atwood, Karyn D. Rode
2025, PLoS ONE (20)
Quantitative fatty acid signature analysis (QFASA) is a common method of estimating the composition of prey species in the diets of consumers from polar and temperate ecosystems in which lipids are an important source of energy. A key characteristic of QFASA is that the large number of fatty acids that...
Towards mobile wind measurements using joust configured ultrasonic anemometer for applications in gas flux quantification
Derek Hollenbeck, Colin W. Edgar, Eugenie Euskirchen, Kristen L. Manies
2025, Drones (9)
Small uncrewed aerial systems (sUASs) can be used to quantify emissions of greenhouse and other gases, providing flexibility in quantifying these emissions from a multitude of sources, including oil and gas infrastructure, volcano plumes, wildfire emissions, and natural sources. However, sUAS-based emission estimates are sensitive to the accuracy of wind...
Variation in energetic balance among free-ranging polar bears during the spring mating and foraging season
Anthony M. Pagano, Stephen N. Atkinson, Louise C. Archer
2025, Arctic Science (11) 1-14
Large carnivores are capable of consuming substantial biomasses that can significantly alter their body mass and condition over short periods. Here we examine the intra-seasonal variation of polar bear (Ursus maritimus Phipps, 1774) body mass, energy intake, and condition in the spring from two subpopulations. We evaluate the biological and temporal...
Slow slip detectability in seafloor pressure records offshore Alaska
Erik Fredrickson, Joan S. Gomberg, William Wilcock, Susan Hautala, Albert Hermann, H. Paul Johnson
2025, Journal of Geophysical Research (128)
In subduction zones worldwide, seafloor pressure data are used to observe tectonic deformation, particularly from megathrust earthquakes and slow slip events (SSEs). However, such measurements are also sensitive to oceanographic circulation-generated pressures over a range of frequencies that conflate with tectonic signals of interest. Using seafloor pressure and temperature data...
