Rhyolitic calderas of the Yukon-Tanana Terrane, east central Alaska: volcanic remnants of a mid-Cretaceous magmatic arc
C. R. Bacon, H.L. Foster, James G. Smith
1990, Journal of Geophysical Research (95) 21451-21461
Four large but poorly exposed rhyolitic calderas are present in the Yukon-Tanana terrane (YTT) in east central Alaska. At least two are mid-Cretaceous in age (~93 Ma). Similar volcanic rocks, the South Fork Volcanics, occur northeast of the Tintina fault in Yukon Territory. Evidence for the calderas consists of thick...
Eruptions of Mount St. Helens : Past, present, and future
Robert I. Tilling, Lyn J. Topinka, Donald A. Swanson
1990, Report
Mount St. Helens, located in southwestern Washington about 50 miles northeast of Portland, Oregon, is one of several lofty volcanic peaks that dominate the Cascade Range of the Pacific Northwest; the range extends from Mount Garibaldi in British Columbia, Canada, to Lassen Peak in northern California. Geologists call Mount St....
Seismic anisotropy due to preferred mineral orientation observed in shallow crustal rocks in southern Alaska
T.M. Brocher, N.I. Christensen
1990, Geology (18) 737-740
Laboratory velocity measurements and structural field relations explain the observation of a significant seismic anisotropy within highly foliated rocks in southern Alaska. The orientation of the principal compressive stress indicates that this anisotropy is not related to extensive dilatancy, but can be satisfactorily...
Bowers Swell: Evidence for a zone of compressive deformation concentric with Bowers Ridge, Bering Sea
M. S. Marlow, A. K. Cooper, S. V. Dadisman, E.L. Geist, P.R. Carlson
1990, Marine and Petroleum Geology (7) 398-409
Bowers Swell is a newly discovered bathymetric feature which is up to 90 m high, between 12 and 20 km wide, and which extends arcuately about 400 km along the northern and eastern sides of Bowers Ridge. The swell was first revealed on GLORIA sonographs and subsequently mapped on seismic...
Evaluation of gases, condensates, and SO2 emissions from Augustine volcano, Alaska: the degassing of a Cl-rich volcanic system
R.B. Symonds, William I. Rose Jr., T.M. Gerlach, Paul H. Briggs, R.S. Harmon
1990, Bulletin of Volcanology (52) 355-374
After the March-April 1986 explosive eruption a comprehensive gas study at Augustine was undertaken in the summers of 1986 and 1987. Airborne COSPEC measurements indicate that passive SO2 emission rates declined exponentially during this period from 380??45 metric tons/day (T/D) on 7/24/86 to 27??6 T/D on 8/24/87. These data are...
A geochemical sampling technique for use in areas of active alpine glaciation: an application from the central Alaska Range
G.C. Stephens, E.B. Evenson, D.E. Detra
1990, Journal of Geochemical Exploration (37) 301-321
In mountainous regions containing extensive glacier systems there is a lack of suitable material for conventional geochemical sampling. As a result, in most geochemical sampling programs a few stream-sediment samples collected at, or near, the terminus of valley glaciers are used...
Reflected and mode-converted seismic waves within the shallow Aleutian subduction zone, southern Kenai Peninsula, Alaska
C.D. Stephens, R.A. Page, J.C. Lahr
1990, Journal of Geophysical Research Solid Earth (95) 6883-6897
Pronounced secondary phases observed in local recordings of quarry shots and earthquakes on the southern Kenai Peninsula, Alaska, are identified as reflected P and S and converted S-to-P phases originating within four depth ranges: in the upper few kilometers of the Cook Inlet Tertiary basin, at midcrustal depths within the...
Computer-aided procedure for counting waterfowl on aerial photographs
D. Bajzak, John F. Piatt
1990, Wildlife Society Bulletin (18) 125-129
Examination of 46 Canada goose goslings yielded 14 species of parasites, including five Protozoa, four Nematoda, two Cestoda, and three Trematoda. Evidence indicates that goslings acquired most of these infections during their first week of life. Some parasites, Prosthogonimus sp., occurred only in younger birds. Others, Leucocytozoon simondi, were...
Growth and equilibrium in sea otter populations
J. A. Estes
1990, Journal of Animal Ecology (59) 385-400
(1) Counts through time were compiled for five sea otter (Enhydra lutris) populations in the north-east Pacific Ocean that were below equilibrium density: Attu Island, south-east Alaska, British Columbia, Washington State, and central California. Similar data were obtained from the equilibrium density population at Amchitka Island in 1971 and 1986....
Site 765: Sedimentology
Leg 123 Shipboard Scientific Party
1990, Proceedings of the Ocean Drilling Program: Initial Reports (123) 113
Various techniques were used to decipher the sedimentation history of Site 765, including Markov chain analysis of facies transitions, XRD analysis of clay and other minerals, and multivariate analysis of smear-slide data, in addition to the standard descriptive procedures employed by the shipboard sedimentologist. This chapter presents brief summaries of...
Components of breeding productivity in a marine bird community: key factors and concordance
Scott A. Hatch, Martha A. Hatch
1990, Canadian Journal of Zoology (68) 1680-1690
We estimated components of annual breeding productivity for eight species of marine birds on the Semidi Islands in the western Gulf of Alaska. Mortality of eggs and young, caused primarily by avian predators, accounted for most of the annual variation in productivity. Failure to produce eggs, clutch size variation, and...
Nest-site selection by Emperor Geese and Cackling Canada Geese
Margaret R. Petersen
1990, The Wilson Bulletin (102) 413-426
Differences were found in habitat structure between nest sites of Emperor Geese (Chen canagicus) and Cackling Canada Geese (Branta canadensis minima) during a 5-year study (1982-1986) at Kokechik Bay, Alaska. Emperor Geese tended to select sites that afforded concealment from avian predators before incubation began. Cackling Canada Geese tended to...
Breeding seasons of oceanic birds in a subarctic colony
Scott A. Hatch, Martha A. Hatch
1990, Canadian Journal of Zoology (68) 1664-1679
We studied the breeding seasons of marine birds on the Semidi Islands, western Gulf of Alaska, from 1976 to 1983. Distributions of laying or hatching observed in 11 species during 1–7 years are presented; less detailed information is available on the breeding schedules of three species. The combined laying period...
Individual variation in behavior and breeding success of Northern Fulmars
Scott A. Hatch
1990, The Auk (107) 750-755
In a sample of breeding Northern Fulmars (Fulmarus glacialis) observed in 4-5 years, up to 43% of the variability in 13 attributes of breeding behavior was consistent among individuals or pairs. Sample means for most attributes were correlated in a predictable way with annual levels of breeding success. Except for...
Immediate impact of the 'Exxon Valdez' oil spill on marine birds
John F. Piatt, Calvin J. Lensink, William Butler, Marshal Kendziorek, David R. Nysewander
1990, The Auk (107) 387-397
On 24 March 1989, the oil tanker 'Exxon Valdez' spilled 260,000 barrels of crude oil in Prince William Sound, Alaska. Oil eventually drifted over $30,000\ {\rm km}^{2}$ of coastal and offshore waters occupied by approximately one million marine birds. More than 30,000 dead birds of 90 species were retrieved from...
Effects of human disturbance on breeding Least and Crested Auklets at St. Lawrence Island, Alaska
John F. Piatt, Bay D. Roberts, Wayne W. Lidster, John L. Wells, Scott A. Hatch
1990, The Auk (107) 342-350
We studied breeding success, chick growth, and diets of Least (Aethia pusilla) and Crested (A. cristatella) auklets on St. Lawrence Island, Alaska, in summer 1987. Least Auklets had higher breeding success on control plots (50-66%) than on disturbed plots (36%). Crested Auklets had a breeding success of 42% on disturbed...
Incubation rhythm in the Fulmar Fulmarus glacialis: Annual variation and sex roles
Scott A. Hatch
1990, Ibis (132) 515-524
I monitored the incubation schedules of Fulmars Fulmarus glacialis in an Alaskan colony by observing nests where the male and female were of different colour phases. Complete shifts of up to 16 days were recorded; the average shift in mid-incubation was 4–6 days. Mean shift length was inversely correlated with...
The importance of subarctic intertidal habitats to shorebirds: A study of the central Yukon-Kuskokwim Delta, Alaska
Robert E. Gill Jr., Colleen M. Handel
1990, The Condor (92) 709-725
A 6-year study of shorebird use of intertidal habitats of the Yukon-Kuskokwim Delta revealed this area to be one of the premiere sites for shorebirds throughout the Holarctic and worthy of designation as a Hemispheric Shorebird Reserve in the Western Hemisphere Shorebird Reserve Network. The study area, which covered 10%...
Site 765: Sediment Lithostratigraphy
Leg 123 Shipboard Scientific Party
1990, Proceedings of the Ocean Drilling Program: Initial Reports (123) 76-94
A 935-m-thick succession of Quaternary through Lower Cretaceous sediments was recovered at Site 765 (Fig. 10). A single core of Quaternary sediment was obtained from Hole 765A; drilling terminated and a new hole was drilled in an attempt to establish the mud line. Quaternary through middle Miocene sediments were cored...
Time allocation by northern fulmars during the breeding season
Scott A. Hatch
1990, Ornis Scandinavica (21) 89-98
Averaged over the whole breeding cycle (pre-laying through mid-chick stage), breeding fulmars spent about 39% of their time at the breeding site and 61% of their time at sea. Annual means of site occupancy before egg-laying were positively correlated with breeding success, suggesting that time allocation was a sensitive indicator...
Is the polar bear (Ursus maritimus) a hibernator? Continued studies on opioids and hibernation
David S. Bruce, Nancy K. Darling, Katheleen J. Seeland, Peter R. Oeltgen, Sita P. Nilekani, Steven C. Amstrup
1990, Pharmacology Biochemistry and Behavior (35) 705-711
Polar bear behavior and biochemistry suggest they may have the ability to hibernate year-round, even though this species is not considered to be a true hibernator. This observation, plus the discovery of a hibernation-induced trigger (HIT) in the blood of black bears, prompted the examination of polar bear blood collected...
Error in telemetry studies: Effects of animal movement on triangulation
Joel A. Schmutz, Gary C. White
1990, Journal of Wildlife Management (54) 506-510
We used Monte Carlo simulations to investigate the effects of animal movement on error of estimated animal locations derived from radio-telemetry triangulation of sequentially obtained bearings. Simulated movements of 0-534 m resulted in up to 10-fold increases in average location error but <10% decreases in location precision when observer-to-animal distances...
Extra-pair copulations in Black Brant
Daniel Welsh, James S. Sedinger
1990, The Condor (92) 242-244
Monogamy is the primary mating system among waterfowl, but extra-pair copulations (EPCs) have been documented in at least 39 species (McKinney et al. 1983). Extra-pair copulations occur in most Holarctic species of dabbling ducks (Anas spp.), but have been recorded in only three species of geese: Lesser Snow Geese, Chen...
Postrelease monitoring of radio-instrumented sea otters in Prince William Sound
C. Monnett, L.M. Rotterman, C. Stack, Daniel H. Monson
Keith Bayha, Jennifer Kormendy, editor(s)
1990, Biological Report 90(12)
Sea otters (Enhydra lutris) that were captured in western Prince William Sound (PWS) or the Gulf of Alaska, treated, and held in captivity at the temporary rehabilitation centers established in response to the T/V Exxon Valdez oil spill were instrumented with radio transmitters, released into eastern PWS, and monitored by...
Effects of visiting black brant nests on egg and nest survival
James S. Sedinger
1990, Journal of Wildlife Management (54) 437-443
I used 2 methods to evaluate the effect of visiting black brant (Branta bernicla nigricans) nests on survival of whole nests and eggs in a single colony on the Yukon-Kuskokwim Delta, Alaska. The first technique regressed survival of nests or eggs during a time interval against interval length. Departure of...
