Nesting habitat relationships of sympatric Crested Caracaras, Red-tailed Hawks, and White-tailed Hawks in South Texas
M.A. Actkinson, W.P. Kuvlesky Jr., C. W. Boal, L.A. Brennan, F. Hernandez
2007, Wilson Journal of Ornithology (119) 570-578
We quantified nesting-site habitats for sympatric White-tailed Hawks (Buteo albicaudatus) (n = 40), Red-tailed Hawks (B. jamaicensis) (n = 39), and Crested Caracaras (Caracara cheriway) (n = 24) in the Coastal Sand Plain of south Texas. White-tailed Hawks and Crested Caracara nest sites occurred in savannas, whereas Red-tailed Hawk nest...
Hazard assessment of the Tidal Inlet landslide and potential subsequent tsunami, Glacier Bay National Park, Alaska
G. F. Wieczorek, E.L. Geist, R.J. Motyka, M. Jakob
2007, Landslides (4) 205-215
An unstable rock slump, estimated at 5 to 10 × 106 m3, lies perched above the northern shore of Tidal Inlet in Glacier Bay National Park, Alaska. This landslide mass has the potential to rapidly move into Tidal Inlet and generate large, long-period-impulse tsunami waves. Field and photographic examination...
Disruptions of stream sediment size and stability by lakes in mountain watersheds: Potential effects on periphyton biomass
A.K. Myers, A.M. Marcarelli, C.D. Arp, M. A. Baker, W.A. Wurtsbaugh
2007, Journal of the North American Benthological Society (26) 390-400
The location of a stream reach relative to other landforms in a watershed is an important attribute. We hypothesized that lakes disrupt the frequency of finer, more mobile sediments and thereby change sediment transport processes such that benthic substrates are more stable (i.e., less mobile) below lakes than above lakes....
Highstand fans in the California borderland: The overlooked deep-water depositional systems
Jacob A. Covault, William R. Normark, Brian W. Romans, Stephan A. Graham
2007, Geology (35) 783-786
Contrary to widely used sequence-stratigraphic models, lowstand fans are only part of the turbidite depositional record; our analysis reveals that a comparable volume of coarse-grained sediment has been deposited in California borderland deep-water basins regardless of sea level. Sedimentation rates and periods of...
Dissolution of biogenic ooze over basement edifices in the equatorial Pacific with implications for hydrothermal ventilation of the oceanic crust
B.A. Bekins, A.J. Spivack, E.E. Davis, L. A. Mayer
2007, Geology (35) 679-682
Recent observations indicate that curious closed depressions in carbonate sediments overlying basement edifices are widespread in the equatorial Pacific. A possible mechanism for their creation is dissolution by fluids exiting basement vents from off-axis hydrothermal flow. Quantitative analysis based on the retrograde solubility...
Potential hazards of environmental contaminants to avifauna residing in the Chesapeake Bay estuary
Barnett A. Rattner, Peter C. McGowan
2007, Waterbirds (30) 63-81
A search of the Contaminant Exposure and Effects-Terrestrial Vertebrates (CEE-TV) database revealed that 70% of the 839 Chesapeake Bay records deal with avian species. Studies conducted on waterbirds in the past 15 years indicate that organochlorine contaminants have declined in eggs and tissues, although p,p'-DDE, total polychlorinated biphenyls (PCBs) and...
Comparative velocity structure of active Hawaiian volcanoes from 3-D onshore-offshore seismic tomography
J. Park, J.K. Morgan, C.A. Zelt, P. G. Okubo, L. Peters, N. Benesh
2007, Earth and Planetary Science Letters (259) 500-516
We present a 3-D P-wave velocity model of the combined subaerial and submarine portions of the southeastern part of the Island of Hawaii, based on first-arrival seismic tomography of marine airgun shots recorded by the onland seismic network. Our model shows that high-velocity materials (6.5-7.0??km/s) lie beneath Kilauea's summit, Koae...
Optimal use of resources structures home ranges and spatial distribution of black bears
M.S. Mitchell, R. A. Powell
2007, Animal Behaviour (74) 219-230
Research has shown that territories of animals are economical. Home ranges should be similarly efficient with respect to spatially distributed resources and this should structure their distribution on a landscape, although neither has been demonstrated empirically. To test these hypotheses, we used home range models that optimize resource use according...
Structure and composition of a watershed-scale sediment information network
W. R. Osterkamp, J. R. Gray, J.B. Laronne, J.R. Martin
2007, International Journal of Sediment Research (22) 238-246
A 'Watershed-Scale Sediment Information Network' (WaSSIN), designed to complement UNESCO's International Sedimentation Initiative, was endorsed as an initial project by the World Association for Sedimentation and Erosion Research. WaSSIN is to address global fluvial-sediment information needs through a network approach based on consistent protocols for the collection, analysis, and storage...
Physical and hormonal examination of Missouri River shovelnose sturgeon reproductive stage: A reference guide
M. L. Wildhaber, D. M. Papoulias, A. J. DeLonay, D. E. Tillitt, J.L. Bryan, M.L. Annis
2007, Journal of Applied Ichthyology (23) 382-401
From May 2001 to June 2002 Wildhaber et al. (2005) conducted monthly sampling of Lower Missouri River shovelnose sturgeon (Scaphirhynchus platorynchus) to develop methods for determination of sex and the reproductive stage of sturgeons in the field. Shovelnose sturgeon were collected from the Missouri River and ultrasonic and endoscopic imagery and...
A new ghost-node method for linking different models and initial investigations of heterogeneity and nonmatching grids
J.E. Dickinson, S.C. James, S. Mehl, M. C. Hill, S. A. Leake, G.A. Zyvoloski, C.C. Faunt, A.-A. Eddebbarh
2007, Advances in Water Resources (30) 1722-1736
A flexible, robust method for linking parent (regional-scale) and child (local-scale) grids of locally refined models that use different numerical methods is developed based on a new, iterative ghost-node method. Tests are presented for two-dimensional and three-dimensional pumped systems that are homogeneous or that have simple heterogeneity. The parent and...
Sexual selection in the squirrel treefrog Hyla squirella: the role of multimodal cue assessment in female choice
Ryan C. Taylor, Bryant W. Buchanan, Jessie L. Doherty
2007, Animal Behaviour (74) 1753-1763
Anuran amphibians have provided an excellent system for the study of animal communication and sexual selection. Studies of female mate choice in anurans, however, have focused almost exclusively on the role of auditory signals. In this study, we examined the effect of both auditory and visual cues on female choice...
Scale-dependent habitat selection of nesting Great Egrets and Snowy Egrets
Eric D. Stolen, J.A. Collazo, H.F. Percival
2007, Waterbirds (30) 384-393
Foraging habitat selection of nesting Great Egrets (Ardea alba) and Snowy Egrets (Egretta thula) was investigated within an estuary with extensive impounded salt marsh habitat. Using a geographic information system, available habitat was partitioned into concentric bands at five, ten, and 15 km radius from nesting colonies to assess the...
Rainfall limit of the N cycle on Earth
Stephanie A. Ewing, Greg Michalski, Mark Thiemens, R.C. Quinn, J. L. Macalady, S. Kohl, Scott D. Wankel, Carol Kendall, Christopher P McKay, Ronald Amundson
2007, Global Biogeochemical Cycles (21)
In most climates on Earth, biological processes control soil N. In the Atacama Desert of Chile, aridity severely limits biology, and soils accumulate atmospheric NO3−. We examined this apparent transformation of the soil N cycle using a series of ancient Atacama Desert soils (>2 My) that vary in rainfall (21...
Reproductive phenologies in a diverse temperate ant fauna
R.R. Dunn, C.R. Parker, M. Geraghty, N.J. Sanders
2007, Ecological Entomology (32) 135-142
1. Ant nuptial flights are central to understanding ant life history and ecology but have been little studied. This study examined the timing of nuptial flights, the synchronicity of nuptial flights (as a potential index of mating strategy), and variation in nuptial flights with elevation and among years in a...
Evidence of lake whitefish spawning in the Detroit River: Implications for habitat and population recovery
E.F. Roseman, G.W. Kennedy, J. Boase, B.A. Manny, T. N. Todd, W. Stott
2007, Journal of Great Lakes Research (33) 397-406
Historic reports imply that the lower Detroit River was once a prolific spawning area for lake whitefish (Coregonus clupeaformis) prior to the construction of the Livingstone shipping channel in 1911. Large numbers of lake whitefish migrated into the river in fall where they spawned on expansive limestone bedrock and gravel...
Changes in ice-margin processes and sediment routing during ice-sheet advance across a marginal moraine
P. G. Knight, C.E. Jennings, R. I. Waller, Z. P. Robinson
2007, Geografiska Annaler, Series A: Physical Geography (89) 203-215
Advance of part of the margin of the Greenland ice sheet across a proglacial moraine ridge between 1968 and 2002 caused progressive changes in moraine morphology, basal ice formation, debris release, ice-marginal sediment storage, and sediment transfer to the distal proglacial zone. When the ice margin is behind the moraine,...
Distributions of pharmaceuticals in an urban estuary during both dry- and wet-weather conditions
M.J. Benotti, Bruce J. Brownawell
2007, Environmental Science & Technology (41) 5795-5802
Pharmaceuticals and selected major human metabolites are ubiquitous in Jamaica Bay, a wastewater-impacted estuary at concentrations in the low ng/L to low ??g/L range. Concentrations throughout the bay are often consistent with conservative behavior during dry-weather conditions, as evidenced by nearly linear concentration-salinity relationships. Deviation from conservative behavior is noted...
Sources and transport of algae and nutrients in a Californian river in a semi-arid climate
Nobuhito Ohte, Randy A. Dahlgren, Steven R. Silva, Carol Kendall, Charles R. Kratzer, Daniel H. Doctor
2007, Freshwater Biology (52) 2476-2493
1. To elucidate factors contributing to dissolved oxygen (DO) depletion in the Stockton Deep Water Ship Channel in the lower San Joaquin River, spatial and temporal changes in algae and nutrient concentrations were investigated in relation to flow regime under the semiarid climate conditions. 2. Chlorophyll-a (chl-a) concentration and loads...
Distribution and sedimentary characteristics of tsunami deposits along the Cascadia margin of western North America
R. Peters, B. Jaffe, G. Gelfenbaum
2007, Sedimentary Geology (200) 372-386
Tsunami deposits have been found at more than 60 sites along the Cascadia margin of Western North America, and here we review and synthesize their distribution and sedimentary characteristics based on the published record. Cascadia tsunami deposits are best preserved, and most...
Oxygen and sulfur isotope systematics of sulfate produced by bacterial and abiotic oxidation of pyrite
N. Balci, Wayne C. Shanks III, B. Mayer, K.W. Mandernack
2007, Geochimica et Cosmochimica Acta (71) 3796-3811
To better understand reaction pathways of pyrite oxidation and biogeochemical controls on ??18O and ??34S values of the generated sulfate in acid mine drainage (AMD) and other natural environments, we conducted a series of pyrite oxidation experiments in the laboratory. Our biological and abiotic experiments were conducted under aerobic conditions...
Manganese-enhanced magnetic resonance microscopy of mineralization
I.E. Chesnick, T.I. Todorov, J.A. Centeno, D.E. Newbury, Justin R. Small, K. Potter
2007, Magnetic Resonance Imaging (25) 1095-1104
Paramagnetic manganese (II) can be employed as a calcium surrogate to sensitize magnetic resonance microscopy (MRM) to the processing of calcium during bone formation. At high doses, osteoblasts can take up sufficient quantities of manganese, resulting in marked changes in water proton T1, T2 and magnetization transfer ratio values compared...
Large-scale scour of the sea floor and the effect of natural armouring processes, land reclamation Maasvlakte 2, port of Rotterdam
S. Boer, E. Elias, S. Aarninkhof, D. Roelvink, T. Vellinga
2007, Conference Paper, Coastal Sediments '07 - Proceedings of 6th International Symposium on Coastal Engineering and Science of Coastal Sediment Processes
Morphological model computations based on uniform (non-graded) sediment revealed an unrealistically strong scour of the sea floor in the immediate vicinity to the west of Maasvlakte 2. By means of a state-of-the-art graded sediment transport model the effect of natural armouring and sorting of bed material on the scour process...
Kinematic GPS solutions for aircraft trajectories: Identifying and minimizing systematic height errors associated with atmospheric propagation delays
S. Shan, M. Bevis, E. Kendrick, G.L. Mader, D. Raleigh, K. Hudnut, M. Sartori, D. Phillips
2007, Geophysical Research Letters (34)
When kinematic GPS processing software is used to estimate the trajectory of an aircraft, unless the delays imposed on the GPS signals by the atmosphere are either estimated or calibrated via external observations, then vertical height errors of decimeters can occur. This problem is clearly manifested when the aircraft is...
Weirs: Counting and sampling adult salmonids in streams and rivers
Christian E. Zimmerman, Laura M. Zabkar
2007, Book chapter, Salmonid field protocols handbook: techniques for assessing status and trends in salmon and trout populations.
Weirs—which function as porous barriers built across stream—have long been used to capture migrating fish in flowing waters. For example, the Netsilik peoples of northern Canada used V-shaped weirs constructed of river rocks gathered onsite to capture migrating Arctic char Salvelinus alpinus (Balikci 1970). Similarly, fences constructed of stakes and...
