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Page 3958, results 98926 - 98950

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Ectoparasitism and the role of green nesting material in the European starling
P.T. Fauth, Christopher H. Kremer, James E. Hines
1991, Oecologia (88) 22-29
The use of green nesting material is widespread among birds. Recent evidence suggests that birds use secondary chemicals contained in green plants to control ectoparasites. We manipulated green nesting material and ectoparasites of European starlings (Sturnus vulgaris) to test two hypotheses: (1) ectoparasites adversely affect prefledging survival and morphometrics or...
Tomographic imaging of subducted lithosphere below northwest Pacific island arcs
R. van der Hilst, R. Engdahl, W. Spakman, G. Nolet
1991, Nature (353) 37-43
The seismic tomography problem does not have a unique solution, and published tomographic images have been equivocal with regard to the deep structure of subducting slabs. An improved tomographic method, using a more realistic background Earth model and surface-reflected as well as direct seismic phases, shows that slabs beneath the...
Conservation of the Yellowstone grizzly bear
David J. Mattson, Matthew M. Reid
1991, Conservation Biology (5) 364-372
We review literature relevant to the conservation of Yellowstone's grizzly bear population and appraise the bear's long-term viability. We conclude that the population is isolated and vulnerable to epidemic perturbation and that the carrying capacity of the habitat is likely to shift downward under conditions of climate change. Viability analyses...
Rare earth elements in Japan Sea sediments and diagenetic behavior of Ce/Ce∗: results from ODP Leg 127
R. Murray, Marilyn R. Buchholtz ten Brink, Hans-Juergen Brumsack, David C. Gerlach, G. Price Russ
1991, Geochimica et Cosmochimica Acta (55) 2453-2466
The relative effects of paleoceanographic and paleogeographic variations, sediment lithology, and diagenetic processes on the recorded rare earth element (REE) chemistry of Japan Sea sediments are evaluated by investigating REE total abundances and relative fractionations in 59 samples from Ocean Drilling Program Leg 127. REE total abundances (ΣREE) in the Japan...
Lead accumulation and osprey production near a mining site on the Coeur d'Alene River, Idaho
Charles J. Henny, Lawrence J. Blus, David J. Hoffman, Robert A. Grove, Jeffrey S. Hatfield
1991, Archives of Environmental Contamination and Toxicology (21) 415-424
Mining and smelting at Kellogg-Smelterville, Idaho, resulted in high concentrations of lead in Coeur d'Alene (CDA) River sediments 15–65 km downstream, where ospreys (Pandion haliaetus) nested. Adult and nestling ospreys living along the CDA River had significantly higher blood lead concentrations than those at Lake Coeur d'Alene (intermediate area) or...
Hydrologic pathways and chemical composition of runoff during snowmelt in Loch Vale Watershed, Rocky Mountain National Park, Colorado, USA
A. Scott Denning, Jill Baron, M. Alisa Mast, Mary Arthur
1991, Water, Air, & Soil Pollution (59) 107-123
Intensive sampling of a stream draining an alpine-subalpine basin revealed that depressions in pH and acid neutralizing capacity (ANC) of surface water at the beginning of the spring snowmelt in 1987 and 1988 were not accompanied by increases in strong acid anions, and that surface waters did not become acidic...
Striped bass stocks and concentrations of polychlorinated biphenyls
Mary C. Fabrizio, Ronald J. Sloan, John F. O'Brien
1991, Transactions of the American Fisheries Society (120) 541-551
Harvest restrictions on striped bass Morone saxatilis fisheries in Atlantic coastal states were relaxed in 1990, but consistent, coastwide regulations of the harvest have been difficult to implement because of the mixed‐stock nature of the fisheries and the recognized contamination of Hudson River fish by polychlorinated biphenyls (PCBs). We...
Low-cost field estimation of yellow perch daily ration
R.S. Hayward, F. Joseph Margraf, D.L. Parrish, B. Vondracek
1991, Transactions of the American Fisheries Society (120) 589-604
We used 2 yearsˈ diel food weight data from stomachs of Lake Erie yellow perch Perca flavescens to make Elliott‐Persson (E–P) estimates of daily ration and to construct consumption response surface (CRS) regression models. The CRS models provided relatively accurate, low‐cost estimates of daily ration from only one to four fish collections...
Analysis and modeling of long‐term stream temperatures on the Steamboat Creek Basin, Oregon: Implications for land use and fish habitat
Steven W. Hostetler
1991, Journal of the American Water Resources Association (27) 637-647
Steamboat Creek basin is an important source of timber and provides crucial spawning and rearing habitat for anadromous steelhead trout (Oncorhynchus mykiss). Because stream temperatures are near the upper limit of tolerance for the survival of juvenile steelhead, the possible long‐term effect of clear‐cut logging on...
Relations among fault behavior, subsurface geology, and three-dimensional velocity models
A.J. Michael, D. Eberhart-Phillips
1991, Science (253) 651-654
The development of three-dimensional P-wave velocity models for the regions surrounding five large earthquakes in California has lead to the recognition of relations among fault behavior and the material properties of the rocks that contact the fault at seismogenic depths; regions of high moment release appear to correlate with high...
40Ar/39Ar age of the Lathrop Wells volcanic center, Yucca Mountain, Nevada
B. D. Turrin, D. Champion, R.J. Fleck
1991, Science (253) 654-657
Paleomagnetic and 40Ar/39Ar analyses from the Lathrop Wells volcanic center, Nevada, indicate that two eruptive events have occurred there. The ages (136 ± 8 and 141 ± 9 thousand years ago) for these two events are analytically indistinguishable. The small angular difference (4.7°) between the paleomagnetic directions from these two events...
Acid precipitation and food quality: Effects of dietary Al, Ca and P on bone and liver characteristics in American black ducks and mallards
Donald W. Sparling
1991, Archives of Environmental Contamination and Toxicology (21) 281-288
American black ducks (Anas rubripes) and mallards (A. platyrhynchos) were fed diets varying in concentrations of aluminum (Al), calcium (Ca), and phosphorus (P) for 10 weeks to identify toxic effects of Al under conditions representative of areas with acid precipitation. Femur and liver tissues were analyzed for Al, Ca, and...
Growth and development of thermoregulation in nestling San Miguel Island Song Sparrows
Mark K. Sogge, Michael D. Kern, Robert Kern, Charles van Riper III
1991, The Condor (93) 773-776
Patterns of growth (reviewed by Ricklefs 1968, 1969; O'Connor 1984) and the development of endothermy (reviewed by Dawson and Hudson 1970, Dunn 1975, Hill and Beaver 1982) have been well-studied in altricial wild birds, especially passerines. But few studies compare grown and thermogenesis in separate populations of the same...
Major and trace element mass flux in fumarolic deposits, Valley of Ten Thousand Smokes, Alaska: Rhyolite-rich protolith
J. J. Papike, T. E. C. Keith, Michael N. Spilde, C.K. Shearer, K. C. Galbreath, J.C. Laul
1991, Geophysical Research Letters (18) 1545-1548
Three fossil fumaroles in rhyolite-rich ash-flow tuff from the lower Valley of Ten Thousand Smokes (VTTS) have been studied to ascertain chemical losses and gains and mineralogical evolution during fumarolic alteration and subsequent cooling and weathering processes. Major oxide and trace element data were interpreted using the isocon method of...
Seismic evidence for magma in the vicinity of Mt. Katmai, Alaska
Peter L. Ward, Andrew M. Pitt, Eliot Endo
1991, Geophysical Research Letters (18) 1537-1540
P-wave traveltime delays of as much as 0.9 sec are consistently observed at one seismic station from local and regional earthquakes 70 to 150 km deep. This station is on the southwest flank of Mt. Trident, the most recently active volcano within Katmai National Park, Alaska. Delays from local shallow...
Paleomagnetism of three upper Jurassic ash-flow sheets in southeastern Arizona: Implications for regional deformation
Jonathan T. Hagstrum, Peter W. Lipman
1991, Geophysical Research Letters (18) 1413-1416
A sequence of three petrologically distinct Upper Jurassic ash-flow tuffs has been sampled for paleomagnetic analysis in the Huachuca Mountains, Canelo Hills, and Mustang Mountains of southeastern Arizona. Site-mean paleomagnetic directions for these units indicate significant vertical-axis rotations between sampling localities (≃15°–40°), and a comparison of these and previously published...
Palaeobotanical evidence for a June 'impact winter' at the Cretaceous/Tertiary boundary
J. A. Wolfe
1991, Nature (352) 420-423
A large bolide impact, such as that thought to have occurred at the Cretaceous/Tertiary (K/T) boundary, should produce large amounts of light-attenuating debris, thereby causing an 'impact winter'1–3. Because of thermal buffering in the oceans, evidence for a brief (1–2 months2–4) impact winter would be found only in terrestrial environments....
Stocking of hatchery-reared striped bass in the Patuxent River, Maryland: Survival, relative abundance, and cost‐effectiveness
R.M. Dorazio, B.M. Florence, C.M. Wooley
1991, North American Journal of Fisheries Management (11) 435-442
Hatchery‐reared fingerlings of striped bass Morone saxatilis were tagged, stocked, and recovered in the Patuxent River, Maryland, to estimate their survival and abundance relative to wild young of the year and to compare the costs and benefits of stocking phase‐I (35–50 mm, total length) and phase‐II (150–200 mm) fish. About 100,000 phase‐I...
H4IIE rat hepatoma cell bioassay-derived 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents in colonial fish-eating waterbird eggs from the Great Lakes
Donald E. Tillitt, Gerald T. Ankley, David A. Verbrugge, John P. Giesy, James P. Ludwig, Timothy J. Kubiak
1991, Archives of Environmental Contamination and Toxicology (21) 91-101
Fish-eating waterbirds from the Great Lakes of North America have shown symptoms of poisoning similar to those observed in laboratory exposures of various avian species to planar halogenated hydrocarbons (PHHs). PHHs, include among others, polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs) and have...