Food availability and offspring sex in a monogamous seabird: insights from an experimental approach
Thomas Merkling, Sarah Leclaire, Etienne Danchin, Emeline Lhuillier, Richard H. Wagner, Joel White, Scott A. Hatch, Pierrick Blanchard
2012, Behavioral Ecology (23) 751-758
Sex allocation theory predicts that parents should favor offspring of the sex that provides the greatest fitness return. Despite growing evidence suggesting that vertebrates are able to overcome the constraint of chromosomal sex determination, the general pattern remains equivocal, indicating a need for experimental investigations. We used an experimental feeding...
Vegetation shifts observed in arctic tundra 17 years after fire
Kirsten Barrett, Adrian V. Rocha, Martine Janet van de Weg, Gaius Shaver
2012, Remote Sensing Letters (3) 729-736
With anticipated climate change, tundra fires are expected to occur more frequently in the future, but data on the long-term effects of fire on tundra vegetation composition are scarce. This study addresses changes in vegetation structure that have persisted for 17 years after a tundra fire on the North Slope...
Structure of marine predator and prey communities along environmental gradients in a glaciated fjord
Martin Renner, Mayumi L. Arimitsu, John F. Piatt
2012, Canadian Journal of Fisheries and Aquatic Sciences (69) 2029-2045
Spatial patterns of marine predator communities are influenced to varying degrees by prey distribution and environmental gradients. We examined physical and biological attributes of an estuarine fjord with strong glacier influence to determine the factors that most influence the structure of predator and prey communities. Our results suggest that some...
Molecular detection of hematozoa infections in tundra swans relative to migration patterns and ecological conditions at breeding grounds
Andrew M. Ramey, Craig R. Ely, Joel A. Schmutz, John M. Pearce, Darryl J. Heard
2012, PLoS ONE (7)
Tundra swans (Cygnus columbianus) are broadly distributed in North America, use a wide variety of habitats, and exhibit diverse migration strategies. We investigated patterns of hematozoa infection in three populations of tundra swans that breed in Alaska using satellite tracking to infer host movement and molecular techniques to assess the...
A simple method for in situ monitoring of water temperature in substrates used by spawning salmonids
Christian E. Zimmerman, James E. Finn
2012, Journal of Fish and Wildlife Management (3) 288-295
Interstitial water temperature within spawning habitats of salmonids may differ from surface-water temperature depending on intragravel flow paths, geomorphic setting, or presence of groundwater. Because survival and developmental timing of salmon are partly controlled by temperature, monitoring temperature within gravels used by spawning salmonids is required to adequately describe the...
High shrew diversity on Alaska's Seward Peninsula: Community assembly and environmental change
Andrew G. Hope
2012, Northwestern Naturalist (93) 101-110
In September 2010, 6 species of shrews (genus: Sorex) were collected at a single locality on the Seward Peninsula of Alaska. Such high sympatric diversity within a single mammalian genus is seldom realized. This phenomenon at high latitudes highlights complex Arctic community dynamics that reflect significant turnover through time as...
Spawning salmon and the fitness of stream-dwelling fishes: Marine-derived nutrients show saturating effects on growth and energy storage in juvenile salmonids
D.J. Rinella, M.S. Wipfli, C. A. Stricker, R. Heintz
2012, Canadian Journal of Fisheries and Aquatic Sciences (69) 73-84
We examined how marine-derived nutrients (MDN), in the form of spawning Pacific salmon, influenced the nutritional status and d15N of stream-dwelling fishes. We sampled juvenile coho salmon (Oncorhynchus kisutch) and Dolly Varden (Salvelinus malma) during spring and fall from 11 south-central Alaskan streams that ranged widely in spawning salmon biomass...
Chronic hydrocarbon exposure of harlequin ducks in areas affected by the Selendang Ayu oil spill at Unalaska Island, Alaska
Paul L. Flint, J.L. Schamber, K.A. Trust, A.K. Miles, J.D. Henderson, B.W. Wilson
2012, Environmental Toxicology and Chemistry (31) 2828-2831
We evaluated chronic exposure of harlequin ducks (Histrionicus histrionicus) to hydrocarbons associated with the 2004 M/V Selendang Ayu oil spill at Unalaska Island, Alaska. We measured levels of hepatic 7-ethoxyresorufin-O-deethylase activity (EROD) in liver biopsy samples as an indicator of hydrocarbon exposure in three oiled bays and one reference bay in...
Using surface velocities to calculate ice thickness and bed topography: A case study at Columbia Glacier, Alaska, USA
R.W. McNabb, R. Hock, Shad O’Neel, Lowell A. Rasmussen, Y. Ahn, M. Braun, H. Conway, S. Herreid, I. Joughin, W.T. Pfeffer, B.E. Smith, M. Truffer
2012, Journal of Glaciology (58) 1151-1164
Information about glacier volume and ice thickness distribution is essential for many glaciological applications, but direct measurements of ice thickness can be difficult and costly. We present a new method that calculates ice thickness via an estimate of ice flux. We solve the familiar continuity equation between adjacent flowlines, which...
Moderating Argos location errors in animal tracking data
David C. Douglas, Rolf Weinziert, Sarah C. Davidson, Roland Kays, Martin Wikelski, Gil Bohrer
2012, Methods in Ecology and Evolution (3) 999-1007
1. The Argos System is used worldwide to satellite-track free-ranging animals, but location errors can range from tens of metres to hundreds of kilometres. Low-quality locations (Argos classes A, 0, B and Z) dominate animal tracking data. Standard-quality animal tracking locations (Argos classes 3, 2 and 1) have larger errors...
Bioenergetics model for estimating food requirements of female Pacific walruses (Odobenus rosmarus divergens)
S.R. Noren, Mark S. Udevitz, C.V. Jay
2012, Marine Ecology Progress Series (460) 261-275
Pacific walruses Odobenus rosmarus divergens use sea ice as a platform for resting, nursing, and accessing extensive benthic foraging grounds. The extent of summer sea ice in the Chukchi Sea has decreased substantially in recent decades, causing walruses to alter habitat use and activity patterns which could affect their energy...
Analysis of low-frequency seismic signals generated during a multiple-iceberg calving event at Jakobshavn Isbræ, Greenland
Fabian Walter, Jason M. Amundson, Shad O’Neel, Martin Truffer, Mark Fahnestock, Helen A. Fricker
2012, Journal of Geophysical Research (117)
We investigated seismic signals generated during a large-scale, multiple iceberg calving event that occurred at Jakobshavn Isbræ, Greenland, on 21 August 2009. The event was recorded by a high-rate time-lapse camera and five broadband seismic stations located within a few hundred kilometers of the terminus. During the event two full-glacier-thickness...
Cenozoic tectono-thermal history of the Tordrillo Mountains, Alaska: Paleocene-Eocene ridge subduction, decreasing relief, and late Neogene faulting
Jeff A. Benowitz, Peter J. Haeussler, Paul W. Layer, Paul B. O'Sullivan, Wes K. Wallace, Robert J. Gillis
2012, Geochemistry, Geophysics, Geosystems (13)
Topographic development inboard of the continental margin is a predicted response to ridge subduction. New thermochronology results from the western Alaska Range document ridge subduction related orogenesis. K-feldspar thermochronology (KFAT) of bedrock samples from the Tordrillo Mountains in the western Alaska Range complement existing U-Pb, 40Ar/39Ar and AFT (apatite fission track)...
Behavioral vs. molecular sources of conflict between nuclear and mitochondrial DNA: The role of male-biased dispersal in a Holarctic sea duck
Jeffrey L. Peters, Kimberly A. Bolender, John M. Pearce
2012, Molecular Ecology (21) 3562-3575
Genetic studies of waterfowl (Anatidae) have observed the full spectrum of mitochondrial (mt) DNA population divergence, from apparent panmixia to deep, reciprocally monophyletic lineages. Yet, these studies often found weak or no nuclear (nu) DNA structure, which was often attributed to male-biased gene flow, a common behaviour within this family....
Effects of sea ice on winter site fidelity of Pacific common eiders (Somateria mollissima v-nigrum)
Margaret R. Petersen, David C. Douglas, Heather M. Wilson, Sarah E. McCloskey
2012, The Auk (129) 399-408
In northern marine habitats, the presence or absence of sea ice results in variability in the distribution of many species and the quality and availability of pelagic winter habitat. To understand the effects of ice on intra- and inter-annual winter site fidelity and movements in a northern sea-duck species, we...
A multi-sensor lidar, multi-spectral and multi-angular approach for mapping canopy height in boreal forest regions
David J. Selkowitz, Gordon Green, Birgit E. Peterson, Bruce Wylie
2012, Remote Sensing of Environment (121) 458-471
Spatially explicit representations of vegetation canopy height over large regions are necessary for a wide variety of inventory, monitoring, and modeling activities. Although airborne lidar data has been successfully used to develop vegetation canopy height maps in many regions, for vast, sparsely populated regions such as the boreal forest biome,...
Characterizing post-drainage succession in Thermokarst Lake Basins on the Seward Peninsula, Alaska with TerraSAR-X Backscatter and Landsat-based NDVI data
Prajna Regmi, Guido Grosse, Miriam C. Jones, Benjamin M. Jones, Katey Walter Anthony
2012, Remote Sensing (4) 3741-3765
Drained thermokarst lake basins accumulate significant amounts of soil organic carbon in the form of peat, which is of interest to understanding carbon cycling and climate change feedbacks associated with thermokarst in the Arctic. Remote sensing is a tool useful for understanding temporal and spatial dynamics of drained basins. In...
Evidence of accelerated beak growth associated with avian keratin disorder in black-capped chickadees (Poecile atricapillus)
Caroline R. Van Hemert, Colleen M. Handel, Todd M. O'Hara
2012, Journal of Wildlife Diseases (48) 686-694
We recently documented an epizootic of beak deformities in more than 2,000 Black-capped Chickadees (Poecile atricapillus) and other wild bird species in North America. This emerging avian disease, which has been termed avian keratin disorder, results in gross overgrowth of the rhamphotheca, the outer, keratinized layer of the beak. To...
Soil data for a collapse-scar bog chronosequence in Koyukuk Flats National Wildlife Refuge, Alaska, 2008
Jonathan A. O’Donnell, Jennifer W. Harden, Kristen L. Manies, M. Torre Jorgenson
2012, Open-File Report 2012-1230
Peatlands in the northern permafrost region store large amounts of organic carbon, most of which is currently stored in frozen peat deposits. Recent warming at high-latitudes has accelerated permafrost thaw in peatlands, which will likely result in the loss of soil organic carbon from previously frozen peat deposits to the...
Polar and brown bear genomes reveal ancient admixture and demographic footprints of past climate change
Webb Miller, Stephan C. Schuster, Andreanna J. Welch, Aakrosh Ratan, Oscar C. Bedoya-Reina, Fangqing Zhao, Hie Lim Kim, Richard C. Burhans, Daniela I. Drautz, Nicola E. Wittekindt, Lynn P. Tomsho, Enrique Ibarra-Laclette, Luis Herrera-Estrella, Elizabeth L. Peacock, Sean Farley, George K. Sage, Karyn D. Rode, Martyn E. Obbard, Rafael Montiel, Lutz Bachmann, Olafur Ingolfsson, Jon Aars, Thomas Mailund, Øystein Wiig, Sandra L. Talbot, Charlotte Lindqvist
2012, Proceedings of the National Academy of Sciences (109) E2382-E2390
Polar bears (PBs) are superbly adapted to the extreme Arctic environment and have become emblematic of the threat to biodiversity from global climate change. Their divergence from the lower-latitude brown bear provides a textbook example of rapid evolution of distinct phenotypes. However, limited mitochondrial and nuclear DNA evidence conflicts in...
Carry-over effects of winter location contribute to variation in timing of nest initiation and clutch size in black brant (Branta bernicla nigricans)
Jason L. Schamber, James S. Sedinger, David H. Ward
2012, The Auk (129) 205-210
We assessed carry-over effects from winter location on timing of nest initiation and clutch size of Black Brant (Branta bernicla nigricans) using observations of individually marked brant breeding at the Tutakoke River colony in Alaska, and wintering along a latitudinal gradient at three areas on the Pacific coast of Baja...
Peat accumulation in drained thermokarst lake basins in continuous, ice-rich permafrost, northern Seward Peninsula, Alaska
Miriam C. Jones, Guido Grosse, Benjamin M. Jones, Katey Walter Anthony
2012, Journal of Geophysical Research G: Biogeosciences (117) G00M07
Thermokarst lakes and peat-accumulating drained lake basins cover a substantial portion of Arctic lowland landscapes, yet the role of thermokarst lake drainage and ensuing peat formation in landscape-scale carbon (C) budgets remains understudied. Here we use measurements of terrestrial peat thickness, bulk density, organic matter content, and basal radiocarbon age...
Predicted eelgrass response to sea level rise and its availability to foraging Black Brant in Pacific coast estuaries
Frank J. Shaughnessy, Whelan Gilkerson, Jeffrey M. Black, David H. Ward, Mark Petrie
2012, Ecological Applications (22) 1743-1761
Managers need to predict how animals will respond to habitat redistributions caused by climate change. Our objective was to model the effects of sea level rise on total eelgrass (Zostera marina) habitat area and on the amount of that area that is accessible to Brant geese (Branta bernicla), specialist grazers...
Local-area-enhanced, 2.5-meter resolution natural-color and color-infrared satellite-image mosaics of the Aynak mineral district in Afghanistan: Chapter E in Local-area-enhanced, high-resolution natural-color and color-infrared satellite-image mosaics of mineral districts in Afghanistan
Philip A. Davis, Laura E. Cagney, Scott A. Arko, Michelle L. Harbin
2012, Data Series 709-E
The U.S. Geological Survey (USGS), in cooperation with the U.S. Department of Defense Task Force for Business and Stability Operations, prepared databases for mineral-resource target areas in Afghanistan. The purpose of the databases is to (1) provide useful data to ground-survey crews for use in performing detailed assessments of the...
Local-area-enhanced, 2.5-meter resolution natural-color and color-infrared satellite-image mosaics of the Badakhshan mineral district in Afghanistan: Chapter F in Local-area-enhanced, high-resolution natural-color and color-infrared satellite-image mosaics of mineral districts in Afghanistan
Philip A. Davis, Scott A. Arko, Michelle L. Harbin
2012, Data Series 709-F
The U.S. Geological Survey (USGS), in cooperation with the U.S. Department of Defense Task Force for Business and Stability Operations, prepared databases for mineral-resource target areas in Afghanistan. The purpose of the databases is to (1) provide useful data to ground-survey crews for use in performing detailed assessments of the...
