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
Mineral constraints on arctic caribou (Rangifer tarandus): a spatial and phenological perspective Mineral constraints on arctic caribou (Rangifer tarandus): a spatial and phenological perspective
Arctic caribou (Rangifer tarandus) have the longest terrestrial migration of any ungulate but little is known about the spatial and seasonal variation of minerals in summer forages and the potential impacts of mineral nutrition on the foraging behavior and nutritional condition of arctic caribou. We investigated the phenology, availability, and mechanistic relationships of calcium...
Authors
K. W. Oster, P.S. Barboza, David D. Gustine, Kyle Joly, R. D. Shively
Analyzing floating and bedfast lake ice regimes across Arctic Alaska using 25 years of space-borne SAR imagery Analyzing floating and bedfast lake ice regimes across Arctic Alaska using 25 years of space-borne SAR imagery
Late-winter lake ice regimes are controlled by water depth relative to maximum ice thickness (MIT). When MIT exceeds maximum water depth, lakes freeze to the bottom with bedfast ice (BI) and when MIT is less than maximum water depth lakes have floating ice (FI). Both airborne radar and space-borne synthetic aperture radar (SAR) imagery (Ku-, X-, C-, and L-band) have been used previously...
Authors
Melanie Engram, Christopher D. Arp, Benjamin M. Jones, Olaniyi A Ajadi, Franz J Meyer
Avian predator buffers against variability in marine habitats with flexible foraging behavior Avian predator buffers against variability in marine habitats with flexible foraging behavior
How well seabirds compensate for variability in prey abundance and composition near their breeding colonies influences their distribution and reproductive success. We used tufted puffins (Fratercula cirrhata) as forage fish samplers to study marine food webs from the western Aleutian Islands (53°N, 173°E) to Kodiak Island (57°N, 153°W), Alaska, during August 2012–2014. Around each colony...
Authors
Sarah K. Schoen, John F. Piatt, Mayumi L. Arimitsu, Brielle Heflin, Erica N. Madison, Gary S. Drew, Martin Renner, Nora A. Rojek, David C. Douglas, Anthony R. DeGange
Energetic solutions of Rock Sandpipers to harsh winter conditions rely on prey quality Energetic solutions of Rock Sandpipers to harsh winter conditions rely on prey quality
Rock Sandpipers Calidris ptilocnemis have the most northerly non-breeding distribution of any shorebird in the Pacific Basin (upper Cook Inlet, Alaska; 61°N, 151°W). In terms of freezing temperatures, persistent winds and pervasive ice, this site is the harshest used by shorebirds during winter. We integrated physiological, metabolic, behavioural and environmental aspects of the non...
Authors
Daniel R. Ruthrauff, Anne Dekinga, Robert E. Gill, Theunis Piersma
Volcanic ash deposition, eelgrass beds, and inshore habitat loss from the 1920s to the 1990s at Chignik, Alaska Volcanic ash deposition, eelgrass beds, and inshore habitat loss from the 1920s to the 1990s at Chignik, Alaska
We quantified the shallowing of the seafloor in five of six bays examined in the Chignik region of the Alaska Peninsula, confirming National Ocean Service observations that 1990s hydrographic surveys were shallower than previous surveys from the 1920s. Castle Bay, Chignik Lagoon, Hook Bay, Kujulik Bay and Mud Bay lost volume as calculated from Mean Lower Low Water (Chart Datum) to the...
Authors
Mark Zimmermann, Gregory T. Ruggerone, Jeffrey T. Freymueller, Nicole Kinsman, David H. Ward, Kyle R. Hogrefe
Convergence of marine megafauna movement patterns in coastal and open oceans Convergence of marine megafauna movement patterns in coastal and open oceans
The extent of increasing anthropogenic impacts on large marine vertebrates partly depends on the animals’ movement patterns. Effective conservation requires identification of the key drivers of movement including intrinsic properties and extrinsic constraints associated with the dynamic nature of the environments the animals inhabit. However, the relative importance of intrinsic versus...
Authors
A. M. M. Sequeira, J.P. Rodriguez, V. M. Eguíluz, R. Harcourt, M. Hindell, D.W. Sims, C.M. Duarte, D.P. Costa, J. Fernandez-Gracia, L.C. Ferreira, G.C. Hays, M. R. Heupel, M.G. Meekan, A. Aven, F. Bailleul, A. M. M. Baylis, M. L. Berumen, C. D. Braun, J. Burns, M.J. Caley, R. Campbell, R.H. Carmichael, E. Clua, L. D. Einoder, Ari Friedlaender, M. E. Goebel, S.D. Goldsworthy, C. Guinet, J. Gunn, D. Hamer, N. Hammerschlag, M. Hammill, L.A. Hückstädt, N.E. Humphries, M.-A. Lea, A. Lowther, A. Mackay, E. McHuron, J. Mckenzie, L. McLeay, C.R. McMahon, K. Mengersen, M. M. C. Muelbert, Anthony M. Pagano, B. Page, N. Queiroz, P. W. Robinson, S. A. Shaffer, M. Shivji, G. B. Skomal, S. Thorrold, S. Villegas-Amtmann, M. Weise, R. Wells, B. Wetherbee, A. Wiebkin, B. Wienecke, M. Thums
Neoproterozoic–early Paleozoic provenance evolution of sedimentary rocks in and adjacent to the Farewell terrane (interior Alaska) Neoproterozoic–early Paleozoic provenance evolution of sedimentary rocks in and adjacent to the Farewell terrane (interior Alaska)
New detrital zircon U-Pb data from the Farewell terrane of interior Alaska illuminate its early provenance evolution and connections with other Alaskan terranes. Five samples come from Neoproterozoic units in the central Farewell terrane. Basal “ferruginous beds” and the overlying Windy Fork Formation have prominent detrital zircon age populations between 2000 and 1800 Ma, with the Windy...
Authors
Julie A. Dumoulin, James V. Jones, Dwight Bradley, Alison B. Till, Stephen E. Box, Paul B. O’Sullivan
Dietary plasticity in a nutrient-rich system does not influence brown bear (Ursus arctos) body condition or denning Dietary plasticity in a nutrient-rich system does not influence brown bear (Ursus arctos) body condition or denning
Behavioral differences within a population can allow use of a greater range of resources among individuals. The brown bear (Ursus arctos) is a generalist omnivore that occupies diverse habitats and displays considerable plasticity in food use. We evaluated whether brown bear foraging that resulted in deviations from a proposed optimal diet influenced body condition and, in turn, denning...
Authors
Lindsey S. Mangipane, Jerrold L. Belant, Diana J. R. Lafferty, David D. Gustine, Tim L. Hiller, Michael E. Colvin, Buck A. Mangipane, Grant V. Hilderbrand
Aeolian stratigraphy describes ice-age paleoenvironments in unglaciated Arctic Alaska Aeolian stratigraphy describes ice-age paleoenvironments in unglaciated Arctic Alaska
Terrestrial paleoenvironmental records with high dating resolution extending into the last ice age are rare from the western Arctic. Such records can test the synchronicity and extent of ice-age climatic events and define how Arctic landscapes respond to rapid climate changes. Here we describe the stratigraphy and sedimentology of a yedoma deposit in Arctic Alaska (the Carter Section)...
Authors
Benjamin V. Gaglioti, Daniel H. Mann, Pamela Groves, Michael L. Kunz, Louise M. Farquharson, Richard E. Reanier, Benjamin M. Jones, Matthew J. Wooller
High-energy, high-fat lifestyle challenges an Arctic apex predator, the polar bear High-energy, high-fat lifestyle challenges an Arctic apex predator, the polar bear
Regional declines in polar bear (Ursus maritimus) populations have been attributed to changing sea ice conditions, but with limited information on the causative mechanisms. By simultaneously measuring field metabolic rates, daily activity patterns, body condition, and foraging success of polar bears moving on the spring sea ice, we found that high metabolic rates (1.6 times greater than...
Authors
Anthony M. Pagano, George M. Durner, Karyn D. Rode, Todd C. Atwood, Stephen N. Atkinson, Elizabeth Peacock, Daniel P. Costa, Megan A. Owen, Terrie M. Williams
Life‐history tradeoffs revealed by seasonal declines in reproductive traits of Arctic‐breeding shorebirds Life‐history tradeoffs revealed by seasonal declines in reproductive traits of Arctic‐breeding shorebirds
Seasonal declines in breeding performance are widespread in wild animals, resulting from temporal changes in environmental conditions or from individual variation. Seasonal declines might drive selection for early breeding, with implications for other stages of the annual cycle. Alternatively, selection on the phenology of nonbreeding stages could constrain timing of the breeding season...
Authors
Emily L. Weiser, Stephen C. Brown, Richard B. Lanctot, H. River Gates, Kenneth F. Abraham, Rebecca L. Bentzen, Joel Bety, Rodney W. Brook, Megan L. Boldenow, Tyrone F. Donnelly, Willow B. English, Scott A. Flemming, Samantha E. Franks, H. Grant Gilchrist, Marie-Andree Giroux, Andrew C. Johnson, Lisa V. Kennedy, Laura Koloski, Eunbi Kwon, Jean-Francois Lamarre, David B. Lank, Nicolas Lecomte, Joseph R. Liebezeit, Laura McKinnon, Erica Nol, 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
Phenotypic plasticity and climate change: Can polar bears respond to longer Arctic summers with an adaptive fast? Phenotypic plasticity and climate change: Can polar bears respond to longer Arctic summers with an adaptive fast?
Plasticity in the physiological and behavioural responses of animals to prolonged food shortages may determine the persistence of species under climate warming. This is particularly applicable for species that can “adaptively fast” by conserving protein to protect organ function while catabolizing endogenous tissues. Some Ursids, including polar bears (Ursus maritimus), adaptively fast...
Authors
John P. Whiteman, Henry J. Harlow, George M. Durner, Eric V Regher, Steven C. Amstrup, Merav Ben-David