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: 3111
Population dynamics of Greater Scaup breeding on the Yukon-Kuskokwim Delta, Alaska Population dynamics of Greater Scaup breeding on the Yukon-Kuskokwim Delta, Alaska
Populations of greater scaup (Aythya marila) remained relatively stable during a period when populations of lesser scaup (A. affinis) have declined from historic levels. To assist in describing these differences in population trends, from 1991 through 2000, we studied the survival, nesting ecology, and productivity of greater scaup on the Yukon-Kuskokwim Delta (Y-K Delta), Alaska, to...
Authors
Paul L. Flint, J. Barry Grand, Thomas F. Fondell, Julie A. Morse
Future for polar bears in a declining sea ice environment: What do we know? Future for polar bears in a declining sea ice environment: What do we know?
During an April 22, 2006, interview on the CBC radio program “The House,” Tim Flannery, author of the recent book “The Weathermakers,” stated, “Projections of the polar bear specialists are that by about 2030, around that date, the species will be extinct because of global warming induced changes in the Arctic sea ice.” That statement was followed on May 4th by quotations in the Toronto...
Authors
Steven C. Amstrup
Comparison of remotely deployed satellite radio transmitters on walruses Comparison of remotely deployed satellite radio transmitters on walruses
No abstract available.
Authors
C.V. Jay, M. P. Heide-Jorgensen, Anthony S. Fischbach, M.V. Jensen, D.F. Tessler, A.V. Jensen
Minding the gap: Frequency of indels in mtDNA control region sequence data and influence on population genetic analyses Minding the gap: Frequency of indels in mtDNA control region sequence data and influence on population genetic analyses
Insertions and deletions (indels) result in sequences of various lengths when homologous gene regions are compared among individuals or species. Although indels are typically phylogenetically informative, occurrence and incorporation of these characters as gaps in intraspecific population genetic data sets are rarely discussed. Moreover, the impact of gaps on estimates of fixation...
Authors
John M. Pearce
Breeding and moulting locations and migration patterns of the Atlantic population of Steller's eiders Polysticta stelleri as determined from satellite telemetry Breeding and moulting locations and migration patterns of the Atlantic population of Steller's eiders Polysticta stelleri as determined from satellite telemetry
This study was designed to determine the spring, summer, autumn, and early winter distribution, migration routes, and timing of migration of the Atlantic population of Steller's eiders Polysticta stelleri. Satellite transmitters were implanted in 20 eiders captured in April 2001 at Vads??, Norway, and their locations were determined from 5 May 2001 to 6 February 2002. Regions where birds
Authors
Margaret R. Petersen, Jan O. Bustnes, Geir H. Systad
Genetic structure of eelgrass Zostera marina meadows in an embayment with restricted water flow Genetic structure of eelgrass Zostera marina meadows in an embayment with restricted water flow
Genetic structure of the seagrass Zostera marina in a coastal lagoon with restricted water flow, and with heterogeneous water residence times and oceanographic characteristics, was assessed using 8 polymorphic microsatellite loci. Analyses of genetic differentiation (θ) and Bayesian clustering suggested that the Z. marina population in San Quintin Bay (SQB) is genetically substructured...
Authors
Raquel Muniz-Salazar, Sandra L. Talbot, George K. Sage, David H. Ward, Alejandro Cabello-Pasini
Demography, genetics, and the value of mixed messages Demography, genetics, and the value of mixed messages
Iverson et al. (2004) used estimates of the homing rate for molting adult Harlequin Ducks (Histrionicus histrionicus) in Alaska to draw inferences about population structure. Homing rates, defined as one minus the ratio of birds recaptured elsewhere to those recaptured at the original banding site, were high (0.95–1.00) for males and females. Iverson et al. (2004) concluded that these...
Authors
John M. Pearce, Sandra L. Talbot
North Kona slump: Submarine flank failure during the early(?) tholeiitic shield stage of Hualalai Volcano North Kona slump: Submarine flank failure during the early(?) tholeiitic shield stage of Hualalai Volcano
The North Kona slump is an elliptical region, about 20 by 60 km (1000-km2 area), of multiple, geometrically intricate benches and scarps, mostly at water depths of 2000–4500 m, on the west flank of Hualalai Volcano. Two dives up steep scarps in the slump area were made in September 2001, using the ROV Kaiko of the Japan Marine Science and Technology Center (JAMSTEC), as part of a...
Authors
P. W. Lipman, M.L. Coombs
Piggyback tectonics: Long-term growth of Kilauea on the south flank of Mauna Loa Piggyback tectonics: Long-term growth of Kilauea on the south flank of Mauna Loa
Compositional and age data from offshore pillow lavas and volcaniclastic sediments, along with on-land geologic, seismic, and deformation data, provide broad perspectives on the early growth of Kilauea Volcano and the long-term geometric evolution of its rift zones. Sulfur-rich glass rinds on pillow lavas and volcaniclastic sediments derived from them document early underwater growth of...
Authors
Peter W. Lipman, Thomas W. Sisson, Michelle L. Coombs, Andrew T. Calvert, Jun-Ichi Kimura
Traversing a boreal forest landscape: Summer movements of Tule Greater White-fronted Geese Traversing a boreal forest landscape: Summer movements of Tule Greater White-fronted Geese
We monitored the movement, distribution and site affinities of radio-marked Tule Greater White-fronted Geese (Anser albifrons elgasi) during spring and summer in Alaska, 1994-1997 and 2004. Our assessment of summer movements was comprehensive, as locations were obtained during prenesting, nesting, and molt for over 90% of geese with active radios captured during winter or the previous...
Authors
Craig R. Ely, K.S. Bollinger, Jerry W. Hupp, D.V. Derksen, J. Terenzi, John Y. Takekawa, D.L. Orthmeyer, T.C. Rothe, M.J. Petrula, D.R. Yparraguirre
Interspecific resource partitioning in sympatric ursids Interspecific resource partitioning in sympatric ursids
The fundamental niche of a species is rarely if ever realized because the presence of other species restricts it to a narrower range of ecological conditions. The effects of this narrower range of conditions define how resources are partitioned. Resource partitioning has been inferred but not demonstrated previously for sympatric ursids. We estimated assimilated diet in relation to body...
Authors
Jerrold L. Belant, Knut Kielland, Erich H. Follmann, Layne G. Adams
Evaluation of aerial survey methods for Dall's sheep Evaluation of aerial survey methods for Dall's sheep
Most Dall's sheep (Ovis dalli dalli) population-monitoring efforts use intensive aerial surveys with no attempt to estimate variance or adjust for potential sightability bias. We used radiocollared sheep to assess factors that could affect sightability of Dall's sheep in standard fixed-wing and helicopter surveys and to evaluate feasibility of methods that might account for sightability...
Authors
Mark S. Udevitz, Brad S. Shults, Layne G. Adams, Christopher Kleckner