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Publications

USGS research activities relevant to Alaska have yielded more than 9400 historical publications. This page features some of the most recent newsworthy research findings.

Filter Total Items: 2891

Analyses on subpopulation abundance and annual number of maternal dens for the U.S. Fish and Wildlife Service on polar bears (Ursus maritimus) in the southern Beaufort Sea, Alaska

The long-term persistence of polar bears (Ursus maritimus) is threatened by sea-ice loss due to climate change, which is concurrently providing an opportunity in the Arctic for increased anthropogenic activities including natural resource extraction. Mitigating the risk of those activities, which can adversely affect the population dynamics of the southern Beaufort Sea (SBS) subpopulation, is an e
Authors
Todd C. Atwood, Jeffrey F. Bromaghin, Vijay P. Patil, George M. Durner, David C. Douglas, Kristin S. Simac

Comparative genomics and genomic epidemiology of mycobacterium avium subsp. paratuberculosis strains

Two phenotypically distinct strains of Mycobacterium avium subsp. paratuberculosis (MAP) were recognized in the 1930s but it was not until the introduction of restriction endonuclease analysis (REA) in the mid-1980s that these two strains, MAP-C and MAP-S, could be distinguished genetically. Since then, a plethora of molecular typing techniques has been applied to MAP isolates (reviewed by Li et a
Authors
Karen Stevenson, Christina Ahlstrom

Reliability of external characteristics to age Barrow’s goldeneye

Accurate assignment of age class is critical for understanding most demographic processes. For waterfowl, most techniques for determining age class require birds in hand, reducing utility for quickly and efficiently sampling a large portion of the population. As an alternative, we sought to establish an observation‐based methodology, achievable in the field with standard optics, for determining ag
Authors
Tyler L. Lewis, Daniel Esler, Danica H. Hogan, W. Sean Boyd, Timothy D. Bowman, Jonathan Thompson

Unfamiliar territory: Emerging themes for ecological drought research and management

Novel forms of drought are emerging globally, due to climate change, shifting teleconnection patterns, expanding human water use, and a history of human influence on the environment that increases the probability of transformational ecological impacts. These costly ecological impacts cascade to human communities, and understanding this changing drought landscape is one of today’s grand challenges.
Authors
Shelley D. Crausbay, Julio L. Betancourt, John B. Bradford, Jennifer M. Cartwright, William C. Dennison, Jason B. Dunham, Carolyn Armstrong Enquist, Abby G. Frazier, Kimberly R. Hall, Jeremy Littell, Charlie H. Luce, Richard Palmer, Aaron R. Ramirez, Imtiaz Rangwala, Laura Thompson, Brianne M. Walsh, Shawn Carter

Palaeotsunamis in the Sino-Pacific region

Palaeotsunami research in the Sino-Pacific region has increased markedly following the 2011 Tōhoku-oki tsunami. Recent studies encompass a variety of potential sources and cover a full range of research activities from detailed studies at individual sites through to region-wide data collation for the purposes of database development. We synthesise palaeotsunami data from around the region drawing
Authors
James Goff, Robert C. Witter, James Terry, Michaela Spiske

A manipulative thermal challenge protocol for adult salmonids in remote field settings

Manipulative experiments provide stronger evidence for identifying cause-and-effect relationships than correlative studies, but protocols for implementing temperature manipulations are lacking for large species in remote settings. We developed an experimental protocol for holding adult Chinook salmon (Oncorhynchus tshawytscha) and exposing them to elevated temperature treatments. The goal of the e
Authors
Daniel S. Donnelly, Vanessa R. von Biela, Stephen D. McCormick, Sarah M. Laske, Michael P. Carey, Shannon C. Waters, Lizabeth Bowen, Randy J Brown, Sean Larson, Christian E. Zimmerman

Transcriptomic response to elevated water temperatures in adult migrating Yukon River Chinook salmon (Oncorhynchus tshawytscha)

Chinook salmon (Oncorhynchus tshawytscha) declines are widespread and may be attributed, at least in part, to warming river temperatures. Water temperatures in the Yukon River and tributaries often exceed 18°C, a threshold commonly associated with heat stress and elevated mortality in Pacific salmon. Untangling the complex web of direct and indirect physiological effects of heat stress on salmon i
Authors
Lizabeth Bowen, Vanessa R. von Biela, Stephen D. McCormick, Amy M. Regish, Shannon C. Waters, Blythe Durbin-Johnson, Monica Britton, Matt Settles, Daniel S. Donnelly, Sarah M. Laske, Michael P. Carey, Randy J Brown, Christian E. Zimmerman

Keystone predators govern the pathway and pace of climate impacts in a subarctic marine ecosystem

Predator loss and climate change are hallmarks of the Anthropocene yet their interactive effects are largely unknown. Here, we show that massive calcareous reefs, built slowly by the alga Clathromorphum nereostratum over centuries to millennia, are now declining because of the emerging interplay between these two processes. Such reefs, the structural base of Aleutian kelp forests, are rapidly erod
Authors
Douglas B Rasher, Robert S Stenek, Jochen Halfar, Kristy J Kroeker, Justin B. Ries, M. Tim Tinker, Phoebe T W Chan, J Fietzke, Nicolas Kamenos, Brenda H. Konar, Jonathan S. Lefcheck, Christopher J D Norley, Ben Weitzman, Isaac T Westfield, James A. Estes

Microbiomes from biorepositories? 16S rRNA bacterial amplicon sequencing of archived and contemporary intestinal samples of wild mammals (Eulipotyphla: Soricidae)

Interest in gut microbial community composition has exploded recently as a result of the increasing ability to characterize these organisms and a growing understanding of their role in host fitness. New technologies, such as next generation amplicon (16S rRNA) sequencing, have enabled identification of bacterial communities from samples of diverse origin (e.g., fecal, skin, genital, environmental,
Authors
Stephen E. Greiman, Joseph A. Cook, Timothy Odem, Katelyn Cranmer, Schuyler W Liphardt, Damian M. Menning, Sarah A. Sonsthagen, Sandra L. Talbot

Influenza A viruses remain infectious for more than seven months in northern wetlands of North America

In this investigation, we used a combination of field- and laboratory-based approaches to assess if influenza A viruses (IAVs) shed by ducks could remain viable for extended periods in surface water within three wetland complexes of North America. In a field experiment, replicate filtered surface water samples inoculated with duck swabs were tested for IAVs upon collection and again after an overw
Authors
Andrew M. Ramey, Andrew B. Reeves, Judith Z. Drexler, Josh T. Ackerman, Susan E. W. De La Cruz, Andrew S. Lang, Christina Leyson, Paul T. Link, Diann Prosser, Gregory J. Robertson, Jordan Wight, Sungsu Youk, Erica Spackman, Mary Pantin-Jackwood, Rebecca L. Poulson, David E. Stallknecht

Drivers and consequences of apex predator diet composition in the Canadian Beaufort Sea

Polar bears (Ursus maritimus) rely on annual sea ice as their primary habitat for hunting marine mammal prey. Given their long lifespan, wide geographic distribution, and position at the top of the Arctic marine food web, the diet composition of polar bears can provide insights into temporal and spatial ecosystem dynamics related to climate-mediated sea ice loss. Polar bears with the greatest ecol
Authors
Katie R. N. Florko, Gregory W. Thiemann, Jeffrey F. Bromaghin

Evidence of prevalent heat stress in Yukon River Chinook salmon

Migrating adult Pacific salmon (Oncorhynchus spp.) are sensitive to warm water (>18 °C), with a range of consequences from decreased spawning success to early mortality. We examined the proportion of Yukon River Chinook salmon (O. tshawytscha) exhibiting evidence of heat stress to assess the potential that high temperatures contribute to freshwater adult mortality in a northern Pacific salmon popu
Authors
Vanessa R. von Biela, Lizabeth Bowen, Stephen D. McCormick, Michael P. Carey, Daniel S. Donnelly, Shannon C. Waters, Amy M. Regish, Sarah M. Laske, Randy J Brown, Sean Larson, Stan Zuray, Christian E. Zimmerman