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: 3082
DNA metabarcoding of feces to infer summer diet of Pacific walruses DNA metabarcoding of feces to infer summer diet of Pacific walruses
Environmental conditions in the Chukchi Sea are changing rapidly and may alter the abundance and distribution of marine species and their benthic prey. We used a metabarcoding approach to identify potentially important prey taxa from Pacific walrus (Odobenus rosmarus divergens) fecal samples (n = 87). Bivalvia was the most dominant class of prey (66% of all normalized counts) and...
Authors
Sarah A. Sonsthagen, Chadwick V. Jay, Robert S. Cornman, Anthony S. Fischbach, Jacqueline M. Grebmeier, Sandra L. Talbot
Late Cenozoic climate change paces landscape adjustments to Yukon River capture Late Cenozoic climate change paces landscape adjustments to Yukon River capture
Late Cenozoic cooling and changes in glacial–interglacial cycle tempo are thought to increase global rates of erosion starting ~3 million years ago (Ma). Bedrock rivers set rates and patterns of erosion in most landscapes, but constraints on river response to late Cenozoic climate change remain elusive. Here, we determine cosmogenic isotope and luminescence ages of well-preserved bedrock...
Authors
Adrian Bender, Richard O. Lease, Lee B. Corbett, Paul R. Bierman, Marc Caffee, Tammy M. Rittenour
Wildfire-initiated talik development exceeds current thaw projections: Observations and models from Alaska's continuous permafrost zone Wildfire-initiated talik development exceeds current thaw projections: Observations and models from Alaska's continuous permafrost zone
As the Arctic warms and wildfire occurrence increases, talik formation in permafrost regions is projected to expand and affect the cycling of water and carbon. Yet, few unified field and modeling studies have examined this process in detail, particularly in areas of continuous permafrost. We address this gap by presenting multimethod, multiseasonal geophysical measurements of permafrost...
Authors
David M. Rey, Michelle A. Walvoord, Burke J. Minsley, Brian A. Ebel, Clifford I. Voss, Kamini Singha
Fish growth rates and lake sulphate explain variation in mercury levels in ninespine stickleback (Pungitius pungitius) on the Arctic Coastal Plain of Alaska Fish growth rates and lake sulphate explain variation in mercury levels in ninespine stickleback (Pungitius pungitius) on the Arctic Coastal Plain of Alaska
Mercury concentrations in freshwater food webs are governed by complex biogeochemical and ecological interactions that spatially vary and are often mediated by climate. The Arctic Coastal Plain of Alaska (ACP) is a heterogeneous, lake-rich landscape where variability in mercury accumulation is poorly understood. Earlier research indicated that the level of catchment influence on lakes...
Authors
Samantha M. Burke, Christian E. Zimmerman, Sarah M. Laske, Joshua C. Koch, Allison M. Derry, Stephanie Guernon, Brian A. Branfireun, Heidi K. Swanson
After-hatch and hatch year Buff-breasted Sandpipers (Calidris subruficollis) can be sexed accurately using morphometric measures After-hatch and hatch year Buff-breasted Sandpipers (Calidris subruficollis) can be sexed accurately using morphometric measures
Determining the sex of birds quickly in the field can help in studies of behavior and distribution, and when selecting particular sexes for deploying tracking devices or collecting samples. However, discerning males from females is difficult in species that are plumage monomorphic and have overlapping sexual-size dimorphism, as in Buff-breasted Sandpipers Calidris subruficollis. We...
Authors
Juliana Bose de Almeida, Iara F. Lopes, Lewis Oring, T. Lee Tibbitts, Lisa M. Pajot, Richard B. Lanctot
Mate fidelity improves survival and breeding propensity of a long‐lived bird Mate fidelity improves survival and breeding propensity of a long‐lived bird
Evolutionary and behavioural ecologists have long been interested in factors shaping the variation in mating behaviour observed in nature. Although much of the research on this topic has focused on the consequences of mate choice and mate change on annual reproductive success, studies of a potential positive link between mate fidelity and adult demographic rates have been comparatively...
Authors
Alan G. Leach, Thomas V. Riecke, James S. Sedinger, David H. Ward, Sean Boyd
Mitochondrial genome diversity and population mitogenomics of Polar cod (Boreogadus saida) and Arctic dwelling gadoids Mitochondrial genome diversity and population mitogenomics of Polar cod (Boreogadus saida) and Arctic dwelling gadoids
High-latitude fish typically exhibit a narrow thermal tolerance window, which may pose challenges when coping with temperatures that shift outside of a species’ range of tolerance. Due to its role in aerobic metabolism and energy balance, the mitochondrial genome is likely critical for the acclimation and adaptation to differing temperature regimes in marine ectotherms. As oceans...
Authors
Robert E. Wilson, Sarah A. Sonsthagen, Noel Sme, Anthony J. Gharrett, Andrew Majewski, Kate Wedemeyer, R. John Nelson, Sandra L. Talbot
Response: Commentary: Variability in Shelf Sedimentation in Response to Fluvial Sediment Supply and Coastal Erosion Over the Past 1,000 Years in Monterey Bay, CA, United States Response: Commentary: Variability in Shelf Sedimentation in Response to Fluvial Sediment Supply and Coastal Erosion Over the Past 1,000 Years in Monterey Bay, CA, United States
No abstract available.
Authors
Joe Carlin, Jason A. Addison, Amy Wagner, Valerie Evelyn Schwartz, Jamie Hayward, Victoria Severin
Sample-size considerations for a study of shorebird nest survival in the 1002 Area, Arctic National Wildlife Refuge, Alaska Sample-size considerations for a study of shorebird nest survival in the 1002 Area, Arctic National Wildlife Refuge, Alaska
Authorization of lease sales for oil development in the 1002 Area of the Arctic National Wildlife Refuge has highlighted gaps in information about biological communities in the area. The U.S. Fish and Wildlife Service, which is planning a study to evaluate spatial variation in the nest survival of tundra-breeding shorebirds to identify hotspots with high nest survival, sought advice from...
Authors
Emily L. Weiser
Dietary fat concentrations influence fatty acid assimilation patterns in Atlantic pollock (Pollachius virens) Dietary fat concentrations influence fatty acid assimilation patterns in Atlantic pollock (Pollachius virens)
A key aspect in the use of fatty acids (FA) to estimate predator diets using Quantitative FA Signature Analysis (QFASA) is the ability to account for FA assimilation through the use of calibration coefficients (CC). Here, we tested the assumption that CC are independent of dietary fat concentrations by feeding Atlantic pollock (Pollachius virens) three formulated diets with very similar...
Authors
Suzanne M. Budge, Katherine Townsend, Santosh P Lall, Jeffrey F. Bromaghin
Annual adult survival drives trends in Arctic-breeding shorebirds but knowledge gaps in other vital rates remain Annual adult survival drives trends in Arctic-breeding shorebirds but knowledge gaps in other vital rates remain
Conservation status and management priorities are often informed by population trends. Trend estimates can be derived from population surveys or models, but both methods are associated with sources of uncertainty. Many Arctic-breeding shorebirds are thought to be declining based on migration and/or overwintering population surveys, but data are lacking to estimate the trends of some...
Authors
Emily L. Weiser, Richard B. Lanctot, Stephen C. Brown, H. River Gates, Joel Bety, Megan L. Boldenow, Rodney W. Brook, Glen S. Brown, Willow B. English, Scott A. Flemming, Samantha E. Franks, H. Grant Gilchrist, Marie-Andree Giroux, Andrew C. Johnson, Steve Kendall, Lisa V. Kennedy, Laura Koloski, Eunbi Kwon, Jean-Francois Lamarre, David B. Lank, Christopher J. Latty, Nicolas Lecomte, Joseph R. Liebezeit, Rebecca L McGuire, Laura McKinnon, Erica Nol, David C. Payer, Johanna Perz, Jennie Rausch, Martin D. Robards, Sarah T. Saalfeld, Nathan R. Senner, Paul A. Smith, Mikhail Soloviev, Diana V Solovyeva, David H. Ward, Paul F. Wood, Brett K. Sandercock
Geochronologic and Hf-isotope framework of Proterozoic rocks from central New Mexico, USA: Formation of the Mazatzal crustal province in an extended continental margin arc Geochronologic and Hf-isotope framework of Proterozoic rocks from central New Mexico, USA: Formation of the Mazatzal crustal province in an extended continental margin arc
The growth of southern Laurentia has been attributed to the accretion of juvenile arc terranes during the successive 1.74-1.68 Ga Yavapai and 1.65-1.60 Ga Mazatzal orogenies. However, in light of the increasing importance of the ca. 1.49-1.40 Ga Mesoproterozoic Picuris orogeny, the tectonic setting in which the Mazatzal crustal province and its distinctive quartzite-rhyolite successions...
Authors
Mark E. Holland, Tyler A. Grambling, Karl E. Karlstrom, James V. Jones, Kimberly N. Nagotko, Christopher G. Daniel