Variables influencing the presence of subyearling fall Chinook salmon in shoreline habitats of the Hanford Reach, Columbia River
K.F. Tiffan, L.O. Clark, R.D. Garland, D.W. Rondorf
2006, North American Journal of Fisheries Management (26) 351-360
Little information currently exists on habitat use by subyearling fall Chinook salmon Oncorhynchus tshawytscha rearing in large, main-stem habitats. We collected habitat use information on subyearlings in the Hanford Reach of the Columbia River during May 1994 and April-May 1995 using point abundance electrofishing. We analyzed measures of physical habitat...
Random versus fixed-site sampling when monitoring relative abundance of fishes in headwater streams of the upper Colorado River basin
M.C. Quist, K.G. Gerow, M.R. Bower, W.A. Hubert
2006, North American Journal of Fisheries Management (26) 1011-1019
Native fishes of the upper Colorado River basin (UCRB) have declined in distribution and abundance due to habitat degradation and interactions with normative fishes. Consequently, monitoring populations of both native and nonnative fishes is important for conservation of native species. We used data collected from Muddy Creek, Wyoming (2003-2004), to...
Mercury in coal and the impact of coal quality on mercury emissions from combustion systems
Allan Kolker, Constance L. Senior, Jeffrey C. Quick
2006, Applied Geochemistry (21) 1821-1836
The proportion of Hg in coal feedstock that is emitted by stack gases of utility power stations is a complex function of coal chemistry and properties, combustion conditions, and the positioning and type of air pollution control devices employed. Mercury in bituminous coal is found primarily within Fe-sulfides, whereas lower...
Short-term oscillations in avian molt intensity: Evidence from the golden eagle Aquila chrysaetos
D. H. Ellis, J.W. Lish, M. Kery, S.M. Redpath
2006, Journal of Avian Biology (37) 642-644
From a year-long study of molt in the golden eagle Aquila chrysaetos, we recorded 2069 contour feathers replaced in 137 d (6 May-19 September). Very few contour feathers were lost outside this period. From precise daily counts of feathers lost, and using time series analysis, we identified short-term fluctuations (i.e.,...
Soil grain analyses at Meridiani Planum, Mars
C.M. Weitz, R. C. Anderson, J.F. Bell III, W. H. Farrand, Kenneth E. Herkenhoff, J. R. Johnson, B.L. Jolliff, R.V. Morris, S. W. Squyres, R.J. Sullivan
2006, Journal of Geophysical Research E: Planets (111)
Grain‐size analyses of the soils at Meridiani Planum have been used to identify rock sources for the grains and provide information about depositional processes under past and current conditions. Basaltic sand, dust, millimeter‐size hematite‐rich spherules interpreted as concretions, spherule fragments, coated partially buried spherules, basalt fragments, sedimentary outcrop fragments, and...
The origin of neap-spring tidal cycles
E.P. Kvale
2006, Marine Geology (235) 5-18
The origin of oceanic tides is a basic concept taught in most introductory college-level sedimentology/geology, oceanography, and astronomy courses. Tides are typically explained in the context of the equilibrium tidal theory model. Yet this model does not take into account real tides in many parts of the world. Not only...
Extreme U-Th disequilibrium in rift-related basalts, rhyolites and granophyric granite and the timescale of rhyolite generation, intrusion and crystallization at Alid volcanic center, Eritrea
J. B. Lowenstern, B. L. A. Charlier, M.A. Clynne, J. L. Wooden
2006, Journal of Petrology (47) 2105-2122
Rhyolite pumices and co-erupted granophyric (granite) xenoliths yield evidence for rapid magma generation and crystallization prior to their eruption at 15·2 ± 2·9 ka at the Alid volcanic center in the Danikil Depression, Eritrea. Whole-rock U and Th isotopic analyses show 230Th excesses up to 50%...
Community maturity, species saturation and the variant diversity- productivity relationships in grasslands
Q. Guo, T. Shaffer, T. Buhl
2006, Ecology Letters (9) 1284-1292
Detailed knowledge of the relationship between plant diversity and productivity is critical for advancing our understanding of ecosystem functioning and for achieving success in habitat restoration efforts. However, effects and interactions of diversity, succession and biotic invasions on productivity remain elusive. We studied newly established communities in relation to preexisting...
Mallard brood movements, wetland use, and duckling survival during and following a prairie drought
Gary L. Krapu, P.J. Pietz, D.A. Brandt, R. R. Cox Jr.
2006, Journal of Wildlife Management (70) 1436-1444
We used radiotelemetry to study mallard (Anas platyrhynchos) brood movements, wetland use, and duckling survival during a major drought (1988-1992) and during the first 2 years of the subsequent wet period (1993-1994) at 4 51-km2 sites in prairie pothole landscapes in eastern North Dakota, USA. About two-thirds of 69 radiomarked...
Damped regional-scale stress inversions: Methodology and examples for southern California and the Coalinga aftershock sequence
J.L. Hardebeck, A.J. Michael
2006, Journal of Geophysical Research B: Solid Earth (111)
We present a new focal mechanism stress inversion technique to produce regional-scale models of stress orientation containing the minimum complexity necessary to fit the data. Current practice is to divide a region into small subareas and to independently fit a stress tensor to the focal mechanisms of each subarea. This...
Effects of increased feeding frequency on growth of hybrid bluegill in ponds
C.R. Sager, D.L. Winkelman
2006, North American Journal of Aquaculture (68) 313-316
Increased feeding frequency has been used in aquaculture to increase growth and food conversion efficiency, and recent laboratory studies have indicated that feeding frequency could be used to reduce the size variation within groups of hybrid bluegills (F1: male bluegill Lepomis macrochirus x female green sunfish L. cyanellus). Our experiment...
Using digital photographs and object-based image analysis to estimate percent ground cover in vegetation plots
J.D. Luscier, W.L. Thompson, J. M. Wilson, B.E. Gorham, L.D. Dragut
2006, Frontiers in Ecology and the Environment (4) 408-413
Ground vegetation influences habitat selection and provides critical resources for survival and reproduction of animals. Researchers often employ visual methods to estimate ground cover, but these approaches may be prone to observer bias. We therefore evaluated a method using digital photographs of vegetation to objectively quantify percent ground cover of...
Modeling nearshore morphological evolution at seasonal scale
D.-J.R. Walstra, P. Ruggiero, G. Lesser, G. Gelfenbaum
2006, Conference Paper, Coastal Dynamics 2005 - Proceedings of the Fifth Coastal Dynamics International Conference
A process-based model is compared with field measurements to test and improve our ability to predict nearshore morphological change at seasonal time scales. The field experiment, along the dissipative beaches adjacent to Grays Harbor, Washington USA, successfully captured the transition between the high-energy erosive conditions of winter and the low-energy...
Using on-site bioassays to determine selenium risk to propagated endangered fishes
Ann L. Allert, James F. Fairchild, Thomas W. May, Linda C. Sappington, N. Darnall, M. Wilson
2006, North American Journal of Fisheries Management (26) 308-316
The Utah Reclamation, Mitigation and Conservation Commission is determining the feasibility of establishing a hatchery and grow-out facility for endangered June suckers Chasmistes liorus at Goshen Warm Springs, Utah. A survey of water quality indicated that selenium and other contaminants may be of concern at Goshen Warm Springs. We conducted...
Imaging the transition from Aleutian subduction to Yakutat collision in central Alaska, with local earthquakes and active source data
D. Eberhart-Phillips, D.H. Christensen, T.M. Brocher, R. Hansen, N.A. Ruppert, Peter J. Haeussler, G.A. Abers
2006, Journal of Geophysical Research B: Solid Earth (111)
In southern and central Alaska the subduction and active volcanism of the Aleutian subduction zone give way to a broad plate boundary zone with mountain building and strike-slip faulting, where the Yakutat terrane joins the subducting Pacific plate. The interplay of these tectonic elements can be best understood by considering...
Denitrification potential of different land-use types in an agricultural watershed, lower Mississippi valley
S. Ullah, S.P. Faulkner
2006, Ecological Engineering (28) 131-140
Expansion of agricultural land and excessive nitrogen (N) fertilizer use in the Mississippi River watershed has resulted in a three-fold increase in the nitrate load of the river since the early 1950s. One way to reduce this nitrate load is to restore wetlands at suitable locations between croplands and receiving...
Response of microbial community composition and function to soil climate change
M. P. Waldrop, M.K. Firestone
2006, Microbial Ecology (52) 716-724
Soil microbial communities mediate critical ecosystem carbon and nutrient cycles. How microbial communities will respond to changes in vegetation and climate, however, are not well understood. We reciprocally transplanted soil cores from under oak canopies and adjacent open grasslands in a California oak-grassland ecosystem to determine how microbial communities respond...
Influence of riffle and snag habitat specific sampling on stream macroinvertebrate assemblage measures in bioassessment
L. Wang, B.W. Weigel, P. Kanehl, K. Lohman
2006, Environmental Monitoring and Assessment (119) 245-273
Stream macroinvertebrate communities vary naturally among types of habitats where they are sampled, which affects the results of environmental assessment. We analyzed macroinvertebrates collected from riffle and snag habitats to evaluate influences of habitat-specific sampling on taxon occurrence, assemblage measures, and biotic indices. We found considerably more macroinvertebrate taxa unique...
DNA damage and external lesions in brown bullheads (Ameiurus nebulosus) from contaminated habitats
X. Yang, J. Meier, L. Chang, M. Rowan, P. C. Baumann
2006, Environmental Toxicology and Chemistry (25) 3035-3038
The Comet assay was used to compare levels of DNA damage in brown bullheads (Ameiurus nebulosus) collected from three known contaminated locations, the Cuyahoga River (OH, USA), Ashtabula River (OH, USA; both tributaries to Lake Erie, USA), and Ashumet Pond (Cape Cod, MA, USA), with brown...
Predicted changes in subyearling fall Chinook salmon rearing and migratory habitat under two drawdown scenarios for John Day Reservoir, Columbia River
K.F. Tiffan, R.D. Garland, D.W. Rondorf
2006, North American Journal of Fisheries Management (26) 894-907
We evaluated the potential effects of two different drawdown scenarios on rearing and migration habitat of subyearling fall Chinook salmon Oncorhynchus tshawytscha in John Day Reservoir on the Columbia River. We compared habitats at normal operating pool elevation with habitats at drawdown to spillway crest elevation and drawdown to the...
Dynamics of seismogenic volcanic extrusion at Mount St Helens in 2004-05
R.M. Iverson, D. Dzurisin, C. A. Gardner, T.M. Gerlach, R.G. LaHusen, M. Lisowski, J. J. Major, S. D. Malone, J.A. Messerich, S.C. Moran, J.S. Pallister, A.I. Qamar, S. P. Schilling, J.W. Vallance
2006, Nature (444) 439-443
The 2004-05 eruption of Mount St Helens exhibited sustained, near-equilibrium behaviour characterized by relatively steady extrusion of a solid dacite plug and nearly periodic shallow earthquakes. Here we present a diverse data set to support our hypothesis that these earthquakes resulted from stick-slip motion along the margins of the plug...
Environmental threats to tidal-marsh vertebrates of the San Francisco Bay estuary
John Y. Takekawa, I. Woo, Hildie Spautz, N. Nur, Grenier J. Letitia, K. Malamud-Roam, Nordby J. Cully, A.N. Cohen, F. Malamud-Roam, Wainwright-De La Cruz
Greenberg R.Maldonado J.E.Droege S.McDonald M.V., editor(s)
2006, Studies in Avian Biology 176-197
The San Francisco Bay and delta system comprises the largest estuary along the Pacific Coast of the Americas and the largest remaining area for tidal-marsh vertebrates, yet tidal marshes have been dramatically altered since the middle of the 19th century. Although recent efforts to restore ecological functions are notable, numerous...
Genetic effects of ELISA-based segregation for control of bacterial kidney disease in Chinook salmon (Oncorhynchus tshawytscha)
J.J. Hard, D.G. Elliott, R.J. Pascho, D.M. Chase, L.K. Park, J. R. Winton, D.E. Campton
2006, Canadian Journal of Fisheries and Aquatic Sciences (63) 2793-2808
We evaluated genetic variation in ability of Chinook salmon (Oncorhynchus tshawytscha) to resist two bacterial pathogens: Renibacterium salmoninarum, the agent of bacterial kidney disease (BKD), and Listonella anguillarum, an agent of vibriosis. After measuring R. salmoninarum antigen in 499 adults by enzyme-linked immunosorbent assay (ELISA), we mated each of 12...
A portable non-invasive trapping array for sampling amphibians and reptiles
A.N. Rice, K.G. Rice, J.H. Waddle, F.J. Mazzotti
2006, Herpetological Review (37) 429-430
[No abstract available]...
Association between wetland disturbance and biological attributes in floodplain wetlands
S. R. Chipps, D.E. Hubbard, K.B. Werlin, N.J. Haugerud, K.A. Powell, John Thompson, T. Johnson
2006, Wetlands (26) 497-508
We quantified the influence of agricultural activities on environmental and biological conditions of floodplain wetlands in the upper Missouri River basin. Seasonally-flooded wetlands were characterized as low impact (non-disturbed) or high impact (disturbed) based on local land use. Biological data collected from these wetlands were used to develop a wetland...
