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Glacial Lake Noatak formed repeatedly during middle and late Pleistocene time as expanding glaciers from the DeLong Mountains blocked the Noatak River valley. Downcutting by the Noatak River has exposed thick sediment successions in bluffs up to 86 m high. Two river bluffs, Nk-26 and Nk-29A, contain correlative organic-rich flood-plain...

Surveys of aggregation sites can provide unbiased estimates of annual trends in population size if the proportion of the population counted at these sites does not vary systematically among years. However, counts at these sites tend to be highly variable and resulting trend estimates typically have poor precision. I developed...

We found up to 10 ppm wet weight of selenium in blood samples collected from emperor geese (Chen canagica) on their breeding grounds on the Yukon‐Kuskokwim Delta in western Alaska, USA. Incubating adult females captured in late May through mid‐June 1997 had significantly higher concentrations of selenium in their blood...

Organochlorine pesticides, polychlorinated biphenyls (PCBs) including non-ortho PCBs, polychlorinated dibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs) were measured in sea otter liver tissue from California, southeast Alaska, and the western Aleutian archipelago collected between 1988 and 1992. Average total dichlorodiphenyltrichloroethane concentrations for California otters (850 μg/kg wet weight) were over 20 times...

We studied productivity, diets, and environmental contaminants in nesting bald eagles from the western Aleutian Islands, Alaska, USA, during the summers of 1993 and 1994. Productivity on Adak, Tanaga, and Amchitka Islands ranged from 0.88 to 1.24 young produced per occupied site and was comparable to that of healthy populations...

The effects of small population size on genetic diversity and subsequent population recovery are theoretically predicted, but few empirical data are available to describe those relations. We use data from four remnant and three translocated sea otter ( Enhydra lutris) populations to examine relations among magnitude and duration of minimum population...

We describe reproductive characteristics of Golden Eagles (Aquila chrysaetos) breeding in Denali National Park, Alaska during an entire snowshoe hare (Lepus americanus) cycle, 1988-1997. Data on nesting eagles were collected at 58 to 72 nesting areas annually using two aerial surveys. Surveys were conducted during the incubation period to determine...

This bibliography contains over 1,700 published and unpublished references on the family Ammodytidae with an emphasis on the genus Ammodytes. The references are alphabetical by author and then by year of publication.Abstracts and summaries are included for the references we have seen and those provided electronically by others. Abstracts written...

The U.S. Marine Mammal Protection Act (MMPA) and International Agreement on the Conservation of Polar Bears mandate that boundaries and sizes of polar bear (Ursus maritimus) populations be known so they can be managed at optimum sustainable levels. However, data to estimate polar bear numbers for the Chukchi/Bering Sea and...

Sand lance (Ammodytes) constitute a major prey for at least some populations of over 100 species of consumer, including 40 species of birds, 12 species of marine mammals, 45 species of fishes, and some invertebrates. Variation in the availability of sand lance (and other forage fishes) can have major effects...

We tested prototype GPS collars on 8 free-ranging wolves (Canis lupus) and 3 white-tailed deer (Odocoileus virginianus) for varying periods between February and August 1997. We programmed the 920-gm collars to make a location attempt 6-96 times per day. The collars were designed to be remotely released from the animal...

The Cambrian Adams Argillite and the Devonian Nation River Formation are two sandstone-bearing units within a remarkably complete Paleozoic stratigraphic section in east-central Alaska. These strata, now foreshortened and fault-bounded, were originally contiguous with miogeoclinal strata to the east that formed as a...

A small Holocene fan is forming where Queen Inlet, a hanging valley, enters West Arm fjord, Glacier Bay, Alaska. Queen fan formed in the last 80 years following retreat of the Little Ice Age glacier that filled Glacier Bay about 200 yr BP. It was built mainly by a turbidite...

We studied egg size variation of Greater Scaup (Aythya marila) nesting on the Yukon-Kuskokwim Delta, Alaska from 1991-1996. Mean egg size was 64.36±0.03 (SE) ml. Egg size did not vary with clutch size or serve as an index of body size. There was less than 2% overlap in total clutch...

Highly reflective linear features occur in water depths of 20-30 m in northern Bristol Bay (Alaska, USA) and are, in places, over 600 m in length. Their length-to-width ratio is over 100:1. The lineations are usually characterized by large transverse ripples with wavelengths of 1-2 m. The lineations trend about...

Temperatures across the northern regions of North America have been increasing for 150 years, and forests have responded to this increase. In the Noatak National Preserve in Alaska, white spruce (Picea glauca [Moench] Voss) forests reach their northern limit, occurring primarily on well-drained sites and as gallery forests along streams....

Rainbow trout native to the McCloud River, California, USA (Oncorhynchus mykiss stonei) are thought to represent a relic, nonanadromous trout adapted to harsh, fragmented environments. These fish, commonly named McCloud River ‘redband’ trout, survive in their most primitive form in a small, spring-fed stream, Sheepheaven Creek, in the upper McCloud...

Permian to Cretaceous melange of the McHugh Complex on the Kenai Peninsula, south-central Alaska includes blocks and belts of graywacke, argillite, limestone, chert, basalt, gabbro, and ultramafic rocks, intruded by a variety of igneous rocks. An oceanic plate stratigraphy is repeated hundreds of times across the map area, but most...

The Kodiak-Katmai geodetic array, nine monuments distributed along a profile trending north-northwestward across Kodiak Island and the Alaska Peninsula, was surveyed in 1993, 1995 and 1997 to determine the deformation at the Alaska-Aleutian subduction zone. Velocities on Kodiak island measured relative to the stable North American...

Male polar bears (Ursus maritimus) have not been successfully instrumented with satellite transmitters because they readily shed collar-mounted transmitters. Seven male polar bears were captured on the pack ice off the northern coast of Alaska and surgically implanted with satellite transmitters with percutaneous antennae into the subcutaneous space of the...

Three 60 m long, 2·8 m high snowfences have been erected to study long-term effects of changing winter snow conditions on arctic and alpine tundra. This paper describes the experimental design and short-term effects. Open-top fiberglass warming chambers are placed along the experimental snow...

We studied genetic structure in polar bear (Ursus maritimus) populations by typing a sample of 473 individuals spanning the species distribution at 16 highly variable microsatellite loci. No genetic discontinuities were found that would be consistent with evolutionarily significant periods of isolation between groups. Direct comparison of movement data and...

We present major- and trace- element geochemical data for 27 amphibolites and six greenstones from three structural packages in the Yukon-Tanana Upland of east-central Alaska: the Lake George assemblage (LG) of Devono-Mississippian augen gneiss, quartz-mica schist, quartzite, and amphibolite; the Taylor Mountain assemblage (TM) of mafic schist and gneiss, marble,...