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The lower Paleozoic (Silurian and Ordovician) carbonate stratal succession is divided into six unnamed stratigraphic units in the northern part of the Taylor Mountains D-1 1:63,360-scale quadrangle of southwestern Alaska. Several of these units have previously been recognized in the McGrath and Medfra quadrangles to the northeast in strata of...

Recent mapping and interpretation of Quaternary geologic features has improved our understanding of the interaction between volcanic, glacial, and tectonic activity in the Cold Bay and False Pass 1:250,000-scale quadrangles on the Alaska Peninsula. The glacial and volcanic record of the map area strongly suggests that continental-shelf glaciations and two...

Landscape variables were employed as indices of habitat heterogeneity, fragmentation, and human influence on the environment to characterize constituent units of a 635 km2 grid covering the state of Pennsylvania. Species richness was determined by overlaying the distributions of all 60 terrestrial mammalian species found within the state. All landscape...

Age structure and morphology differ among Pacific salmon (Oncorhynchus spp.) populations. Sexual selection and reproductive capacity (fecundity and egg size) generally favor large (old), deep-bodied fish. We hypothesized that natural selection from physical access to spawning grounds and size-biased predation by bears, Ursus spp., opposes such large, deep-bodied salmon. Accordingly, size and shape...

Use of high densities of newly recruited Pacific herring Clupea pallasi for the closed-pound spawn-on-kelp (PPSOK) fishery in Prince William Sound, Alaska, was associated with increased gamete retention, decreased product quality, and increased prevalence of viral hemorrhagic septicemia virus (VHSV) relative to the confinement of older cohorts at lower densities. To maximize...

Effects of color bands on adult birds have been investigated in many studies, but much less is known about the effects of bands on birds banded at hatch. We captured Semipalmated Sandpiper (Calidris pusilla) chicks at hatch on the Alaskan North Slope and attached 0–3 bands to them. The chicks...

Park managers are concerned that moose (Alces alces), caribou (Rangifer tarandus), and grizzly bears (Ursus arctos) may be avoiding areas along the 130 km road through Denali National Park as a result of high traffic volume, thus decreasing opportunities for visitors to view wildlife. A wildlife monitoring system was developed in...

Although forage quality strongly affects gosling growth and consequently juvenile survival, the relative use of different plant communities by brood rearing geese has been poorly studied. On the Yukon-Kuskokwim Delta, Alaska, population growth and juvenile recruitment of Emperor Geese (Chen canagica) are comparatively low, and it is unknown whether their...

One hundred thirty-nine taxa of lichens including two lichen parasites are reported from St. Matthew and St. Paul Islands in the Bering Sea. Caloplaca lithophila is new to Alaska. Wide-ranging arctic-alpine and boreal species dominate the lichens; a coastal element is moderately represented, while amphi-Beringian species form a minor element....

Measures of repeatability have long been used to assess patterns of variation in egg size within and among females. We compared different analytical approaches for estimating repeatability of egg size of Black Brant. Separate estimates of repeatability for eggs of each clutch size and laying sequence number varied from 0.49...

We measured surface elevations, stage of annual peak flooding, and sedimentation along 10 toposequences across coastal ecosystems on the Yukon-Kuskokwim (Y-K) Delta in western Alaska during 1994-1998 to assess some of the physical processes affecting ecosystem distribution. An ecotype was assigned to each of 566 points, and differences in elevations...

We present data on geographic variation in polychlorinated biphenyl (PCB) congeners in adult female polar bears (Ursus maritimus) from Svalbard eastward to the Chukchi Sea. Blood samples from 90 free-living polar bears were collected in 1987–1995. Six PCB congeners, penta to octa chlorinated (PCB-99, -118, -153, -156, -180,...

This issue of Reviews in Fish Biology and Fisheries contains six papers addressing several critical aspects of hybridization in fishes and aquatic organisms. Hybridization is a phenomenon long recognized in fishes (Hubbs, 1920, 1955; Schwarz, 1981), as well as in other plant and vertebrate taxa, despite some rather dogmatic proclamations...

We studied nutrient reserve dynamics of female Lesser Scaup (Aythya affinis) to identify sources of intraspecific variation in strategies of nutrient acquisition for meeting the high nutritional and energetic costs of egg formation. We collected data from interior Alaska and combined these with data for Lesser Scaup from midcontinent breeding...

Carbonate rocks of the Lisburne Group (Carboniferous-Permian) occur widely throughout northern Alaska. In the NPRA, seismic mapping and well penetrations show that the Lisburne occurs throughout the subsurface except in northernmost NPRA where it is missing by depositional onlap. Lisburne strata encountered in 11 exploratory wells in the northern part...

Techniques for the hydraulic restoration of placer-mined streams and floodplains were developed in Denali National Park and Preserve, Alaska. The two-year study at Glen Creek focused on a design of stream and floodplain geometry using hydraulic capacity and shear stress equations. Slope and sinuosity values were based on regional relationships....

No abstract available....

Alaska is home to more than 40 active volcanoes, many of which have erupted violently and repeatedly in the last 200 years. This CD-ROM contains 97 digitized color 35-mm images which represent a small fraction of thousands of photographs taken by Alaska Volcano Observatory scientists, other researchers, and private citizens....

As part of the U.S. Geological Survey?s National Water-Quality Assessment Program, ground-water samples were collected from 34 existing wells in the Cook Inlet Basin in south-central Alaska during 1999. All ground-water samples were from aquifers composed of glacial or alluvial sediments. The water samples were used to determine the occurrence...

Seasonal properties of vegetation covering northern boreal and arctic landscapes are considered important as input to numerous climate change studies. In this study, multitemporal phenological characteristics of Alaskan vegetation were studied for the State as a whole, and 19 of 20 ecoregions were studied using seasonally truncated, composited advanced very...

Between August 3 and 8,2000,the Alaska Volcano Observatory completed a Global Positioning System (GPS) survey at Augustine Volcano, Alaska. Augustine is a frequently active calcalkaline volcano located in the lower portion of Cook Inlet (fig. 1), with reported eruptions in 1812, 1882, 1909?, 1935, 1964, 1976, and 1986 (Miller et...

The effect of urbanization on stream macroinvertebrate communities was examined by using data gathered during a 1999 reconnaissance of 14 sites in the Municipality of Anchorage, Alaska. Data collected included macroinvertebrate abundance, water chemistry, and trace elements in bed sediments. Macroinvertebrate relative-abundance data were edited and used in metric and...

This report is preliminary and has not been reviewed for conformity with U.S. Geological Survey editorial standards or with the North American Stratigraphic Code. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government....

The Yukon River Basin, which encompasses 330,000 square miles in northwestern Canada and central Alaska (Fig. 1), is one of the largest and most diverse ecosystems in North America. The Yukon River is also fundamental to the ecosystems of the eastern Bering Sea and Chukchi Sea, providing most of the...