Subduction-zone magnetic anomalies and implications for hydrated forearc mantle
R.J. Blakely, T.M. Brocher, R.E. Wells
2005, Geology (33) 445-448
Continental mantle in subduction zones is hydrated by release of water from the underlying oceanic plate. Magnetite is a significant byproduct of mantle hydration, and forearc mantle, cooled by subduction, should contribute to long-wavelength magnetic anomalies above subduction zones. We test this hypothesis with a quantitative model of the Cascadia...
Geographic variation in survival and migratory tendency among North American Common Mergansers
John M. Pearce, John A. Reed, Paul L. Flint
2005, Journal of Field Ornithology (76) 109-118
Movement ecology and demographic parameters for the Common Merganser (Mergus merganser americanus) in North America are poorly known. We used band-recovery data from five locations across North America spanning the years 1938–1998 to examine migratory patterns and estimate survival rates. We examined competing time-invariant, age-graduated models with program MARK...
Population genetic structure of annual and perennial populations of Zostera marina L. along the Pacific coast of Baja California and the Gulf of California
Raquel Muñiz-Salazar, Sandra L. Talbot, George K. Sage, David H. Ward, Alejandro Cabello-Pasini
2005, Molecular Ecology (14) 711-722
The Baja California peninsula represents a biogeographical boundary contributing to regional differentiation among populations of marine animals. We investigated the genetic characteristics of perennial and annual populations of the marine angiosperm, Zostera marina, along the Pacific coast of Baja California and in the Gulf of California, respectively. Populations of Z....
Benthic invertebrate community structure is influenced by forest succession after clearcut logging in southeastern Alaska
O. Hernandez, R.W. Merritt, M.S. Wipfli
2005, Hydrobiologia (533) 45-59
To assess the effects of timber harvesting on headwater streams in upland forests, benthic community structure was contrasted among four dominant forest management types (old growth, red alder-dominated young growth, conifer-dominated young growth, clearcut) and instream habitats (woody debris, cobble, gravel) in southeastern Alaska. Benthos in streams of previously harvested...
Population size and trend of Yellow-billed Loons in northern Alaska
Susan L. Earnst, Robert A Stehn, Robert Platte, William W. Larned, Edward J. Mallek
2005, Condor (107) 289-304
The Yellow-billed Loon (Gavia adamsii) is of conservation concern due to its restricted range, small population size, specific habitat requirements, and perceived threats to its breeding and wintering habitat. Within the U.S., this species breeds almost entirely within the National Petroleum Reserve-Alaska, nearly all of which is open, or proposed...
Serosurvey of selected zoonotic agents in polar bears (Ursus maritimus)
H. Rah, B.B. Chomel, Erich H. Follmann, R.W. Kasten, C.H. Hew, T.B. Farver, G.W. Garner, Steven C. Amstrup
2005, Veterinary Record (156) 7-13
Between 1982 and 1999 blood samples were collected from 500 polar bears (Ursus maritimus) captured in the Beaufort and Chukchi seas, to determine the seroprevalence of Brucella species, Toxoplasma gondii, and Trichinella species infections. The bears were classified into four age groups, cubs, yearlings, subadults and adults. Brucella and Toxoplasma...
InSAR studies of Alaska volcanoes
Zhong Lu, Chuck Wicks, Daniel Dzurisin, John A. Power
2005, Korean Journal of Remote Sensing (21) 59-72
Interferometric synthetic aperture radar (InSAR) is a remote sensing technique capable of measuring ground surface deformation with sub-centimeter precision and spatial resolution in tens-ofmeters over a large region. This paper describes basics of InSAR and highlights our studies of Alaskan volcanoes with InSAR images acquired from European ERS-l and ERS-2,...
Parallel structure among environmental gradients and three trophic levels in a subarctic estuary
Suzann G. Speckman, John F. Piatt, C. V. Minte-Vera, Julia K. Parrish
2005, Progress in Oceanography (66) 25-65
We assessed spatial and temporal variability in the physical environment of a subarctic estuary, and examined concurrent patterns of chlorophyll α abundance (fluorescence), and zooplankton and forage fish community structure. Surveys were conducted in lower Cook Inlet, Alaska, during late July and early August from 1997 through 1999. Principle components analysis...
Capture-recapture methods in practice
Bryan F.J. Manly, Steven C. Amstrup, Trent L. McDonald
Steven C. Amstrup, Trent L. McDonald, Bryan F.J. Manly, editor(s)
2005, Book chapter, Handbook of capture-recapture analysis
No abstract available....
Analysis of vegetation distribution in Interior Alaska and sensitivity to climate change using a logistic regression approach
M.P. Calef, A. D. McGuire, H.E. Epstein, T.S. Rupp, H.H. Shugart
2005, Journal of Biogeography (32) 863-878
Aim: To understand drivers of vegetation type distribution and sensitivity to climate change. Location: Interior Alaska. Methods: A logistic regression model was developed that predicts the potential equilibrium distribution of four major vegetation types: tundra, deciduous forest, black spruce forest and white spruce forest based on elevation, aspect, slope, drainage...
Oceanographic conditions structure forage fishes into lipid-rich and lipid-poor communities in lower Cook Inlet, Alaska, USA
Alisa A. Abookire, John F. Piatt
2005, Marine Ecology Progress Series (287) 229-240
Forage fishes were sampled with a mid-water trawl in lower Cook Inlet, Alaska, USA, from late July to early August 1996 to 1999. We sampled 3 oceanographically distinct areas of lower Cook Inlet: waters adjacent to Chisik Island, in Kachemak Bay, and near the Barren Islands. In 163 tows using...
Relationship of otolith strontium-to-calcium ratios and salinity: Experimental validation for juvenile salmonids
Christian E. Zimmerman
2005, Canadian Journal of Fisheries and Aquatic Sciences (62) 88-97
Analysis of otolith strontium (Sr) or strontium-to-calcium (Sr:Ca) ratios provides a powerful tool to reconstruct the chronology of migration among salinity environments for diadromous salmonids. Although use of this method has been validated by examination of known individuals and translocation experiments, it has never been validated under controlled experimental conditions....
Impact of millennial-scale Holocene climate variability on eastern North American terrestrial ecosystems: Pollen-based climatic reconstruction
Debra A. Willard, C.E. Bernhardt, D.A. Korejwo, S.R. Meyers
2005, Global and Planetary Change (47) 17-35
We present paleoclimatic evidence for a series of Holocene millennial-scale cool intervals in eastern North America that occurred every ???1400 years and lasted ???300-500 years, based on pollen data from Chesapeake Bay in the mid-Atlantic region of the United States. The cool events are indicated by significant decreases in pine...
Allocating harvests among polar bear stocks in the Beaufort Sea
Steven C. Amstrup, George M. Durner, I. Stirling, T. L. McDonald
2005, Arctic (58) 247-259
Recognition that polar bears are shared by hunters in Canada and Alaska prompted development of the “Polar Bear Management Agreement for the Southern Beaufort Sea.” Under this Agreement, the harvest of polar bears from the southern Beaufort Sea (SBS) is shared between Inupiat hunters of Alaska and Inuvialuit hunters of...
Role of land-surface changes in arctic summer warming
F. S. Chapin III, M. Sturm, Mark C. Serreze, J.P. McFadden, J.R. Key, A.H. Lloyd, A. D. McGuire, T.S. Rupp, A.H. Lynch, Joshua P. Schimel, J. Beringer, W.L. Chapman, H.E. Epstein, E.S. Euskirchen, L. D. Hinzman, G. Jia, C.-L. Ping, K.D. Tape, C.D.C. Thompson, D.A. Walker, J.M. Welker
2005, Science (310) 657-660
A major challenge in predicting Earth's future climate state is to understand feedbacks that alter greenhouse-gas forcing. Here we synthesize field data from arctic Alaska, showing that terrestrial changes in summer albedo contribute substantially to recent high-latitude warming trends. Pronounced terrestrial summer warming in arctic Alaska correlates with a lengthening...
Breeding ecology of Spectacled Eiders Somateria fischeri in Northern Alaska
J. Bart, S.L. Earnst
2005, Wildfowl (55) 83-98
Spectacled Eiders Somateria fischeri were studied on the Colville River delta during 1994-1999, prior to oil field development, to document aspects of breeding biology that are poorly known, especially for northern-nesting populations. Both sexes arrived June 6-12; many males remained for only about 10 days. Density on the 178-km2 study...
Ordovician "sphinctozoan" sponges from Prince of Wales Island, southeastern Alaska
J.K. Rigby, Susan M. Karl, R. B. Blodgett, J.F. Baichtal
2005, Journal of Paleontology (79) 862-870
A faunule of silicified hypercalcified "sphinctozoan" sponges has been recovered from a clast of Upper Ordovician limestone out of the Early Devonian Karheen Formation on Prince of Wales Island in southeastern Alaska. Included in the faunule are abundant examples of the new genus Girtyocoeliana, represented by Girtyocoeliana epiporata (Rigby and...
Fire effects on soil organic matter content, composition, and nutrients in boreal interior Alaska
J. C. Neff, J.W. Harden, G. Gleixner
2005, Conference Paper, Canadian Journal of Forest Research
Boreal ecosystems contain a substantial fraction of the earth's soil carbon stores and are prone to frequent and severe wildfires. In this study, we examine changes in element and organic matter stocks due to a 1999 wildfire in Alaska. One year after the wildfire, burned soils contained between 1071 and...
Distribution and density of moose in relation to landscape characteristics: Effects of scale
J.A.K. Maier, J. M. Ver Hoef, A. D. McGuire, R.T. Bowyer, L. Saperstein, H.A. Maier
2005, Conference Paper, Canadian Journal of Forest Research
We analyzed the relation between early winter distribution and density of female moose (Alces alces L.) and habitat heterogeneity in interior Alaska. We tested for effects of vegetation type, topography, distance to rivers and towns, occurrence and timing of fire, and landscape metrics. A spatial linear model was used to...
Mudstone sedimentation at high latitudes: Ice as a transport medium for mud and supplier of nutrients
J.H.S. Macquaker, M.A. Keller
2005, Journal of Sedimentary Research (75) 696-709
Controls on mudstone deposition at high latitudes are poorly known relative to low latitudes. In recent sediments deposited in these environments, ice significantly influences sediment transport and primary productivity. The products of ice transport are relatively well known in glacimarine settings, but are less well known from below melting sea...
Spatial and temporal variations in the age structure of Arctic sea ice
G. I. Belchansky, David C. Douglas, Nikita G. Platonov
2005, Geophysical Research Letters (32)
Spatial and temporal variations in the age structure of Arctic sea ice are investigated using a new reverse chronology algorithm that tracks ice-covered pixels to their location and date of origin based on ice motion and concentration data. The Beaufort Gyre tends to harbor the oldest (>10 years old) sea...
Co-occurrence of Pacific sleeper sharks Somniosus pacificus and harbor seals Phoca vitulina in Glacier Bay
S. James Taggart, A.G. Andrews, Jennifer Mondragon, E.A. Mathews
2005, Alaska Fishery Research Bulletin (11) 113-117
We present evidence that Pacific sleeper sharks Somniosus pacificus co-occur with harbor seals Phoca vitulina in Glacier Bay, Alaska, and that these sharks scavenge or prey on marine mammals. In 2002, 415 stations were fished throughout Glacier Bay on a systematic sampling grid. Pacific sleeper sharks were caught at 3...
Ice elevations and surface change on the Malaspina Glacier, Alaska
J. Sauber, B. Molnia, C. Carabajal, S. Luthcke, R. Muskett
2005, Geophysical Research Letters (32) 1-4
Here we use Ice, Cloud and land Elevation Satellite (ICESat)-derived elevations and surface characteristics to investigate the Malaspina Glacier of southern Alaska. Although there is significant elevation variability between ICESat tracks on this glacier, we were able to discern general patterns in surface elevation change by using a regional digital...
Interferometric synthetic aperture radar study of Okmok volcano, Alaska, 1992-2003: Magma supply dynamics and postemplacement lava flow deformation
Z. Lu, Timothy Masterlark, Daniel Dzurisin
2005, Journal of Geophysical Research B: Solid Earth (110) 1-18
Okmok volcano, located in the central Aleutian arc, Alaska, is a dominantly basaltic complex topped with a 10-km-wide caldera that formed circa 2.05 ka. Okmok erupted several times during the 20th century, most recently in 1997; eruptions in 1945, 1958, and 1997 produced lava flows within the caldera. We used...
Seasonal marine growth of Bristol Bay sockeye salmon (Oncorhynchus nerka) in relation to competition with Asian pink salmon (O. gorbuscho) and the 1977 ocean regime shift
Gregory T. Ruggerone, Ed Farley, Jennifer L. Nielsen, Peter Hagen
2005, Fishery Bulletin (103) 355-370
Recent research demonstrated significantly lower growth and survival of Bristol Bay sockeye salmon (Oncorhynchus nerka) during odd-numbered years of their second or third years at sea (1975, 1977, etc.), a trend that was opposite that of Asian pink salmon (O. gorbuscha) abundance. Here we evaluated seasonal growth trends of Kvichak...
