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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: 3104

Family Salmonidae Truchas; Trouts and salmons Family Salmonidae Truchas; Trouts and salmons

No abstract available.
Authors
D.A. Hendrickson, J. L. Nielsen, Richard L. Mayden, S.M. Norris

Patterns of growth and body condition in sea otters from the Aleutian archipelago before and after the recent population decline Patterns of growth and body condition in sea otters from the Aleutian archipelago before and after the recent population decline

1. Growth models for body mass and length were fitted to data collected from 1842 sea otters Enhydra lutris shot or live-captured throughout south-west Alaska between 1967 and 2004. Growth curves were constructed for each of two main year groups: 1967–71 when the population was at or near carrying capacity and 1992–97 when the population was in steep decline. Analyses of data collected...
Authors
K.L. Laidre, J. A. Estes, M. T. Tinker, James L. Bodkin, Daniel H. Monson, K. Schneider

Nesting habitat of the Tule Greater White-fronted Goose Anser albifrons elgasi Nesting habitat of the Tule Greater White-fronted Goose Anser albifrons elgasi

This paper presents the first information on the availability and use of nesting habitat by the rare Tule Greater White-fronted Goose Anser albifrons elgasi. The breeding range was sampled by marking geese with radio transmitters on wintering and moulting areas, and tracking them to nest sites in Alaska. Nesting habitat was described at the scales of ecoregion, wetland ecosystem...
Authors
R.V. Densmore, Craig R. Ely, K.S. Bollinger, S. Kratzer, Mark S. Udevitz, D.J. Fehringer, T.C. Rothe

Techniques for identifying predators of goose nests Techniques for identifying predators of goose nests

We used cameras and artificial eggs to identify nest predators of dusky Canada goose Branta canadensis occidentalis nests during 1997-2000. Cameras were set up at 195 occupied goose nests and 60 artificial nests. We placed wooden eggs and domestic goose eggs that were emptied and then filled with wax or foam in an additional 263 natural goose nests to identify predators from marks in the
Authors
R. Michael Anthony, J.B. Grand, T.F. Fondell, David A. Miller

The conservation and population status of the world's waders at the turn of the millennium The conservation and population status of the world's waders at the turn of the millennium

Using information from many sources, but especially data collated for the third edition of Wetlands International’s Waterbird Population Estimates, we review the status of the world’s waders in the late 1990s. There are widespread declines in most regions and biotopes caused principally by loss and degradation of wetland (and other) habitats. On different flyways, between 33%and 68% of...
Authors
David A. Stroud, Andy Baker, D.E. Blanco, Nick C. Davidson, B. Ganter, Robert E. Gill, P.M. Gonzalez, L. Haanstra, R. I. G. Morrison, Theunis Piersma, D. Scott, O. Thorup, R. West, J.L. Wilson, Christoph Zockler

Pelagic seabird surveys in the Tuamotu and Gambier Archipelagos, French Polynesia Pelagic seabird surveys in the Tuamotu and Gambier Archipelagos, French Polynesia

We conducted pelagic seabird surveys in the Gambier and Tuamotu Archipelagos in the southeastern Pacific Ocean totaling 40 hours during 7-27 March 2003 and 22.5 hours during 22-27 July 2001. We used a 300-m-wide strip transect to estimate seabird density, and we estimated relative abundance of birds at all distances. In 2001, we observed a total of 326 birds of 18 species. The mean...
Authors
Eric A. Vanderwerf, Ray J. Pierce, Verena A. Gill, Graham Wragg, Philippe Raust, T. Lee Tibbitts

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

Summary of preliminary 2D inundation modeling for three Hattian landslide dam breach scenarios Summary of preliminary 2D inundation modeling for three Hattian landslide dam breach scenarios

On October 8, 2005, a M 7.6 earthquake near Muzafarrabad, Pakistan, triggered a landslide that dammed the Karli River and one of its tributaries about 4 km upstream of the confluence of the Karli and Jhelum rivers near the town of Hattian Bala. The smaller dam on the tributary of the Karli River has been artificially breached and is no longer a hazard. When the larger dammed lake on the...
Authors
Roger P. Denlinger, Daniel R.H. O’Connell, Matt Jones

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

Kittiwakes strategically reduce investment in replacement clutches Kittiwakes strategically reduce investment in replacement clutches

Many life-history traits are expressed interactively in life, but to a varying extent on different occasions. Changes in trait expression can be accounted for by differences in the quality of the environment (‘environmental constraint’ hypothesis) or by strategic adjustments, if the relative contribution of the trait to fitness varies with time (‘strategic allocation’ hypothesis). In...
Authors
J. Gasparini, A. Roulin, V.A. Gill, Scott A. Hatch, T. Boulinier

Simulating the influences of various fire regimes on caribou winter habitat Simulating the influences of various fire regimes on caribou winter habitat

Caribou are an integral component of high‐latitude ecosystems and represent a major subsistence food source for many northern people. The availability and quality of winter habitat is critical to sustain these caribou populations. Caribou commonly use older spruce woodlands with adequate terrestrial lichen, a preferred winter forage, in the understory. Changes in climate and fire regime...
Authors
T. Scott Rupp, Mark Olson, Layne G. Adams, Bruce W. Dale, Kyle Joly, Jonathan Henkelman, William B. Collins, Anthony M. Starfield

Spatial and temporal variation in sea otter demography Spatial and temporal variation in sea otter demography

1) Better information on historical and current population dynamics is central to understanding patterns of growth and decline in the California sea otter population. We developed a maximum likelihood-based analytical method to estimate historical age/sex specific vital rates as well as spatial and temporal variation in vital rates from longitudinal databases on population census numbers...
Authors
M. Tim Tinker, Daniel F. Doak, James A. Estes, Brian B. Hatfield, Michelle M. Steadler, James L. Bodkin
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