Cavity-nesting birds and the cavity-tree resource in plains cottonwood bottomlands
James A. Sedgwick, Fritz L. Knopf
1986, Journal of Wildlife Management (50) 247-252
Densities of, and potential nesting substrates for, cavity-nesting birds were examined in a mature plains cottonwood (Populus sargentii) community in northeastern Colorado. Although snag (dead tree) densities were low (0.66/ha), the cavity-nesting guild included 7 species with densities ≤ 463 birds/100 ha. This finding suggests that cavity nesters...
Comparison of four artificial substrates and the Ponar grab for benthic invertebrate collection
Keith V. Slack, Rodger F. Ferreira, Robert C. Averett
1986, Journal of the American Water Resources Association (22) 237-248
Four different bottom‐placed artificial substrates were compared with the Ponar grab for collecting benthic invertebrates. Artificial substrate samples of organisms were larger and more diverse than those of the grab. Barbeque Basket samplers caught the most taxa and individuals and Beak Trays caught the least. Chironomids and crustaceans were dominant...
Parasitization of meadow voles, Microtus pennsylvanicus (ORD), by American dog ticks, Dermacentor variabilis (Say), and adult tick movement during high host density
J. F. Carroll, J.D. Nichols
1986, Journal of Entomological Science (21) 102-113
The numbers of host-seeking adult American dog ticks, Dermacentor variabilis (Say), in a sweet gum field in Maryland reflected changes in the population density of a host species, the meadow vole, Microtus pennsylvanicus (Ord), which within 1.5 yr fell from an estimated 157 to 8 voles on a 0.8 ha grid. During high vole...
Crustal structure of Oaxaca, Mexico, from seismic refraction measurements
C.M. Valdes, Walter D. Mooney, S.K. Singh, C. Lomnitz, James H. Luetgert, C.E. Helsley, B.T.R. Lewis, M. Mena
1986, Bulletin of the Seismological Society of America (76) 547-563
Seismic refraction and gravity data have been analyzed to obtain a model of the compressional-wave velocity structure of the ocean-to-continent transition in the State of Oaxaca in southwestern Mexico. Crustal thickness on the continent at the latitude 18°N is 45 ± 4 km, based on reflected phases from the Moho...
Stratigraphic potential of Bolboforma significantly increased by new finds in the North Atlantic and South Pacific
C. Wylie Poag, A. L. Karowe
1986, Palaios (1) 162-171
Until now, the genus Bolboforma, a problematic group of calcareous microfossils, has been recorded only in Oligocene to Pliocene marine sedimentary rocks, chiefly in the eastern North Atlantic region. We add to this eastern North Atlantic record six new sites and eleven undescribed species from the continental slopes of Ireland...
Northern pintail body condition during wet and dry winters in the Sacramento Valley, California
Michael R. Miller
1986, Journal of Wildlife Management (50) 189-198
Body weights and carcass composition of male and female adult northern pintails (Anas acuta) were investigated in the Sacramento Valley, California, from August to March 1979-82. Pintails were lightweight, lean, and had reduced breast, leg, and heart muscles during August-September. Ducks steadily gained weight after arrival; and body, carcass (body...
Groundwater transport of strontium 90 in a glacial outwash environment
Kenneth L. Kipp Jr., Kenneth G. Stollenwerk, David B. Grove
1986, Water Resources Research (22) 519-530
As part of the investigation of groundwater contamination at a uranium-scrap recovery plant at Wood River Junction, Rhode Island, laboratory experiments led to the development of a model for predicting the transport of strontium 90 in glacial outwash sediments based on an approximate mechanism for ion exchange. The multicomponent system...
Physiological condition of autumn-banded mallards and its relationship to hunting vulnerability
Gary R. Hepp, Robert J. Blohm, Robert E. Reynolds, James E. Hines, James D. Nichols
1986, Journal of Wildlife Management (50) 177-183
An important topic of waterfowl ecology concerns the relationship between the physiological condition of ducks during the nonbreeding season and fitness, i.e., survival and future reproductive success. We investigated this subject using direct band recovery records of mallards (Anas platyrhynchos) banded in autumn (1 Oct-15 Dec) 1981-83 in the Mississippi...
Internal-wave currents as a mechanism to account for large sand waves in Navarinsky Canyon head, Bering Sea
H. A. Karl, D.A. Cacchione, P.R. Carlson
1986, Journal of Sedimentary Research (56) 706-714
Sand waves are found in the heads of four of five large submarine canyons that incise the northern continental margin of the Bering Sea. The sand waves occur in a restricted depth zone of about 175-490 m. Those in Navarinsky Canyon, the area surveyed in most detail, are best developed...
Sediment transport simulation in an armoured stream
Robert T. Milhous, Jeffrey B. Bradley, Cindy L. Loeffler
1986, Book, Proceedings of the Fourth Federal Interagency Sedimentation Conference
Improved methods of calculating bed material stability and transport must be developed for a gravel bed stream having an armoured surface in order to use the HEC-6 model to examine channel change. Good possibilities exist for use of a two layer model based on the Schoklitsch and the Einstein-Brown...
Volcano monitoring at the U.S. Geological Survey's Hawaiian Volcano Observatory
Christina C. Heliker, J. D. Griggs, T. Jane Takahashi, Thomas L. Wright
Henry Spall, editor(s)
1986, Earthquakes & Volcanoes (USGS) (18) 4-69
The island of Hawaii has one of the youngest landscapes on Earth, formed by frequent addition of new lava to its surface. Because Hawaiian are generally nonexplosive and easily accessible, the island has long attracted geologists interested in studying the extraordinary power of volcanic eruptions. The U.S. Geological Survey's Hawaiian Volcano...
Comment and Reply on “Ouachita trough: Part of a Cambrian failed rift system”: COMMENT
Keith B. Ketner, R. L. Ethington, John E. Repetski, Reuben James
Ross, C. G. Stone
1986, Geology (14) 627-627
No abstract available....
National atlas: Territorial growth
H. George Stoll
1986, Report
No abstract available....
Preparing a FWS cumulative impacts program: January 1985 workshop proceedings
Samuel C. Williamson, Carl L. Armour, Richard L. Johnson
1986, Report, Biological Report
No abstract available....
Miocene diatoms from Richmond, Virginia
George William Andrews
1986, Journal of Paleontology (60) 497-538
In downtown Richmond, Va., a highly diatomaceous deposit contains a diatom assemblage in which 87 taxa have been identified. The diatoms indicate that this sedimentary unit is correlative with Lithologic Unit 19 of the Choptank Formation of middle Miocene age. Also in Richmond, a sedimentary unit correlated with the Eastover...
The application of habitat modeling to the desert tortoise (Gopherus agassizii)
Melvin L. Schamberger, Frederick B. Turner
1986, Herpetologica (42) 134-138
Habitat modeling offers an approach to understanding some management problems of desert tortoises (Gopherus agassizii) and to focusing new research efforts. Modeling can provide (1) a method to organize existing information, (2) a means to identify whether physical habitat or some factor outside the scope of the habitat model...
Modeling contamination of shallow unconfined aquifers through infiltration beds
D.W. Ostendorf
1986, Water Resources Research (22) 375-382
We model the transport of a simply reactive contaminant through an infiltration bed and underlying shallow, one-dimensional, unconfined aquifer with a plane, steeply sloping bottom in the assumed absence of dispersion and downgradient dilution. The effluent discharge and ambient groundwater flow under the infiltration beds are presumed to form a...
Predictive accuracy of a ground-water model--Lessons from a postaudit
Leonard F. Konikow
1986, Groundwater (24) 173-184
Hydrogeologic studies commonly include the development, calibration, and application of a deterministic simulation model. To help assess the value of using such models to make predictions, a postaudit was conducted on a previously studied area in the Salt River and lower Santa Cruz River basins in central Arizona. A deterministic,...
Renesting Characteristics of Captive Mallards on Experimental Ponds
G.A. Swanson, T.L. Shaffer, J.F. Wolf, F.B. Lee
1986, Journal of Wildlife Management (50) 32-38
Renesting characteristics of captive wild-strain mallards (Anas platyrhynchos) were investigated on experimental ponds in southcentral North Dakota during the breeding seasons of 1976-81. Renesting efforts and egg production increased during the 1st 3 years. Post-yearling females that experienced clutch loss during early incubation produced 3 clutches of eggs during the...
Miocene silicoflagellates from Chatham Rise, Deep Sea Drilling Project Site 594
David Bukry
1986, Initial Reports of the D.S.D.P. (90) 925-937
Miocene silicoflagellates, dominated by Mesocena, are identified and correlated from Site 594 to other Deep Sea Drilling Project sites. Relative paleotemperature values from silicoflagellates at Site 594 are very low, supporting the evidence of the associated cold-water, low-diversity Coccolith assemblages. The greatest abundances of Mesocena diodon nodosa yet recorded occur...
Cation-ratio and accelerator radiocarbon dating of rock varnish on Mojave artifacts and landforms
R.I. Dorn, D.B. Bamforth, T.A. Cahill, J. C. Dohrenwend, B. D. Turrin, D.J. Donahue, A.J.T. Jull, A. Long, M.E. Macko, E.B. Weil, D.S. Whitley, T.H. Zabel
1986, Science (231) 830-833
The first accelerator radiocarbon dates of rock varnishes are reported along with potassium/argon ages of lava flows and conventional radiocarbon dates of pluvial lake shorelines, in an empirical calibration of rock varnish K+ + Ca2+/Ti4+ ratios with age in the Mojave Desert, eastern California. This calibration was used to determine the cation-ratio...
Discussion of "Aquifer test analysis in fractured rocks with linear flow pattern" by Z. Sen
Paul A. Heish
1986, Groundwater (24) 530-530
No abstract available. ...
Kovats and lee retention indices determined by gas chromatography/mass spectrometry for organic compounds of environmental interest
Colleen E. Rostad, Wilfred E. Pereira
1986, Journal of Separation Science (9) 328-334
Retention indices of standard organic compounds of environmental interest were determined by gas chromatography/mass spectrometry, using a DB‐5 fused‐silica capillary column. Retention indices are useful references for tentative compound identification by gas chromatography, or confirmation by gas chromatography/mass spectrometry. They provide elution order for isomers that...
Palynological and iridium anomalies at Cretaceous-Tertiary boundary, south-central Saskatchewan
D. J. Nichols, D.M. Jarzen, C. J. Orth, P. Q. Oliver
1986, Science (231) 714-717
The Cretaceous-Tertiary boundary in south-central Saskatchewan is marked by coincident anomalies in abundance of iridium and fern spores at the extinction level of a suite of Cretaceous pollen taxa. Evidence of disruption of the terrestrial flora includes the fern-spore abundance anomaly and local extinction of as much as 30 percent...
Strain accumulation in the Shumagin and Yakataga seismic gaps, Alaska
J.C. Savage, M. Lisowski, W.H. Prescott
1986, Science (231) 585-587
Strain accumulation during the 1980-85 interval has been measured by means of trilateration surveys in the Shumagin and Yakataga seismic gaps, which are the two regions identified as the most likely sites for the next great thrust earthquakes along the Alaska-Aleutian arc. No significant strain accumulation was detected in the...
