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
Combined analysis of roadside and off-road breeding bird survey data to assess population change in Alaska
Management interest in North American birds has increasingly focused on species that breed in Alaska, USA, and Canada, where habitats are changing rapidly in response to climatic and anthropogenic factors. We used a series of hierarchical models to estimate rates of population change in 2 forested Bird Conservation Regions (BCRs) in Alaska based on data from the roadside North American Breeding Bi
Authors
Colleen M. Handel, John R. Sauer
New constraints on coseismic slip during southern Cascadia subduction zone earthquakes over the past 4600 years implied by tsunami deposits and marine turbidites
Forecasting earthquake and tsunami hazards along the southern Cascadia subduction zone is complicated by uncertainties in the amount of megathrust fault slip during past ruptures. Here, we estimate slip on hypothetical ruptures of the southern part of the megathrust through comparisons of late Holocene Cascadia earthquake histories derived from tsunami deposits on land and marine turbidites offsho
Authors
George R. Priest, Robert C. Witter, Yinglong J. Zhang, Chris Goldfinger, Kelin Wang, Jonathan C. Allan
Detect and exploit hidden structure in fatty acid signature data
Estimates of predator diet composition are essential to our understanding of their ecology. Although several methods of estimating diet are practiced, methods based on biomarkers have become increasingly common. Quantitative fatty acid signature analysis (QFASA) is a popular method that continues to be refined and extended. Quantitative fatty acid signature analysis is based on differences in the
Authors
Jeffrey F. Bromaghin, Suzanne M. Budge, Gregory W. Thiemann
Hydrologic impacts of changes in climate and glacier extent in the Gulf of Alaska watershed
High‐resolution regional‐scale hydrologic models were used to quantify the response of late 21st century runoff from the Gulf of Alaska (GOA) watershed to changes in regional climate and glacier extent. NCEP Climate Forecast System Reanalysis data were combined with five Coupled Model Intercomparison Project Phase 5 general circulation models (GCMs) for two representative concentration pathway (RC
Authors
Jordan Beamer, Dave Hill, Daniel Mcgrath, Anthony A. Arendt, Christian Kienholz
Tracer-based evidence of heterogeneity in subsurface flow and storage within a boreal hillslope
Runoff from boreal hillslopes is often affected by distinct soil boundaries, including the frozen boundary and the organic – mineral boundary (OMB), where highly porous and hydraulically-conductive organic material overlies fine-grained mineral soils. Viewed from the surface, ground cover appears as a patchwork on sub-meter scales, with thick, moss mats interspersed with lichen-covered, silty soil
Authors
Joshua C. Koch, Ryan C. Toohey, D.M. Reeves
Increased Arctic sea ice drift alters adult female polar bear movements and energetics
Recent reductions in thickness and extent have increased drift rates of Arctic sea ice. Increased ice drift could significantly affect the movements and the energy balance of polar bears (Ursus maritimus) which forage, nearly exclusively, on this substrate. We used radio-tracking and ice drift data to quantify the influence of increased drift on bear movements, and we modeled the consequences for
Authors
George M. Durner, David C. Douglas, Shannon Albeke, John P. Whiteman, Steven C. Amstrup, Evan Richardson, Ryan H. Wilson, Merav Ben-David
PeRL: A circum-Arctic Permafrost Region Pond and Lake database
Ponds and lakes are abundant in Arctic permafrost lowlands. They play an important role in Arctic wetland ecosystems by regulating carbon, water, and energy fluxes and providing freshwater habitats. However, ponds, i.e., waterbodies with surface areas smaller than 1. 0 × 104 m2, have not been inventoried on global and regional scales. The Permafrost Region Pond and Lake (PeRL) database presents th
Authors
Sina Muster, Kurt Roth, Moritz Langer, Stephan Lange, Fabio Cresto Aleina, Annett Bartsch, Anne Morgenstern, Guido Grosse, Benjamin M. Jones, A. B. K. Sannel, Ylva Sjöberg, Frank Gunther, Christian Andresen, Alexandra Veremeeva, Prajna R. Lindgren, Frédéric Bouchard, Mark J. Lara, Daniel Fortier, Simon Charbonneau, Tarmo A. Virtanen, Gustaf Hugelius, J. Palmtag, Matthias B. Siewert, William J. Riley, Charles Koven, Julia Boike
Autonomous acoustic recorders reveal complex patterns in avian detection probability
Avian point‐count surveys are typically designed to occur during periods when birds are consistently active and singing, but seasonal and diurnal patterns of detection probability are often not well understood and may vary regionally or between years. We deployed autonomous acoustic recorders to assess how avian availability for detection (i.e., the probability that a bird signals its presence dur
Authors
Sarah J. Thompson, Colleen M. Handel, Lance B. McNew
Genetic assessment of the effects of streamscape succession on coho salmon Oncorhynchus kisutch colonization in recently deglaciated streams
Measures of genetic diversity within and among populations and historical geomorphological data on stream landscapes were used in model simulations based on approximate Bayesian computation (ABC) to examine hypotheses of the relative importance of stream features (geomorphology and age) associated with colonization events and gene flow for coho salmon Oncorhynchus kisutch breeding in recently degl
Authors
Kim T. Scribner, Chad Soiseth, Jeffrey J. McGuire, G. Kevin Sage, Lyman K. Thorsteinson, J. L. Nielsen, E. Knudsen
Puffins reveal contrasting relationships between forage fish and ocean climate in the North Pacific
Long-term studies of predator food habits (i.e., ‘predator-based sampling’) are useful for identifying patterns of spatial and temporal variability of forage nekton in marine ecosystems. We investigated temporal changes in forage fish availability and relationships to ocean climate by analyzing diet composition of three puffin species (horned puffin Fratercula corniculata, tufted puffin Fratercula
Authors
William J. Sydeman, John F. Piatt, Sarah Ann Thompson, Marisol Garcia-Reyes, Scott A. Hatch, Mayumi L. Arimitsu, Leslie Slater, Jeffrey C. Williams, Nora A. Rojek, Stephani G. Zador, Heather M. Renner
Glacierized headwater streams as aquifer recharge corridors, subarctic Alaska
Arctic river discharge has increased in recent decades although sources and mechanisms remain debated. Abundant literature documents permafrost thaw and mountain glacier shrinkage over the past decades. Here we link glacier runoff to aquifer recharge via a losing headwater stream in subarctic Interior Alaska. Field measurements in Jarvis Creek (634 km2), a subbasin of the Tanana and Yukon Rivers,
Authors
Anna K. Lilledahl, Anne Gadeke, Shad O'Neel, T. A. Gatesman, T. A. Douglas
Decadal declines in avian herbivore reproduction: density-dependent nutrition and phenological mismatch in the Arctic
A full understanding of population dynamics depends not only on estimation of mechanistic contributions of recruitment and survival, but also knowledge about the ecological processes that drive each of these vital rates. The process of recruitment in particular may be protracted over several years, and can depend on numerous ecological complexities until sexually mature adulthood is attained. We a
Authors
Megan V. Ross, Ray T. Alisaukas, David C. Douglas, Dana K. Kellett