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Page 1515, results 37851 - 37875

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Using the internet to understand angler behavior in the information age
Dustin R. Martin, Brenda M. Pracheil, Jason A. DeBoer, Gene R. Wilde, Kevin L. Pope
2012, Fisheries (37) 458-463
Declining participation in recreational angling is of great concern to fishery managers because fishing license sales are an important revenue source for protection of aquatic resources. This decline is frequently attributed, in part, to increased societal reliance on electronics. Internet use by anglers is increasing and fishery managers may use...
Estimating and predicting collection probability of fish at dams using multistate modeling
John M. Plumb, William P. Connor, Kenneth F. Tiffan, Christine M. Moffitt, Russell W. Perry, Noah S. Adams
2012, Transactions of the American Fisheries Society (141) 1364-1373
Dams can be equipped with a bypass that routes a portion of the fish that enter the turbine intakes away from the powerhouse into flumes, where they can be counted. Daily passage abundance can be estimated by dividing the number of fish counted in the bypass by the sampling rate and then...
An evaluation of a mitigation strategy for deer-vehicle collisions
John A. Bissonette, Silvia Rosa
2012, Wildlife Biology (18) 414-423
High mule deer Odocoileus hemionus mortality in southwestern Utah led to the establishment of a mitigation strategy with two major objectives: 1) reduction of wildlife-vehicle collisions and 2) restoration of landscape connectivity to facilitate wildlife movement across the roaded landscape. During our study, we assessed the effectiveness of the mitigation...
Long-term change along the Colorado River in Grand Canyon National Park (1889-2011)
R. H. Webb, J. Belnap, M. L. Scott, J.M. Friedman, T.C. Esque
2012, Newsletter
The Colorado River and its riverine resources have undergone profound changes since completion of Glen Canyon Dam in 1963, as every river runner with any history in Grand Canyon will attest. Long-term monitoring data are difficult to obtain for high-value resource areas (Webb et al. 2009), particularly in remote parts...
Discovering shared segments on the migration route of the bar-headed goose by time-based plane-sweeping trajectory clustering
Ze Luo, Yan Baoping, John Y. Takekawa, Diann J. Prosser
2012, Journal of Information and Computational Science (9) 5093-5100
We propose a new method to help ornithologists and ecologists discover shared segments on the migratory pathway of the bar-headed geese by time-based plane-sweeping trajectory clustering. We present a density-based time parameterized line segment clustering algorithm, which extends traditional comparable clustering algorithms from temporal and spatial dimensions. We present a...
Elemental mapping by Dawn reveals exogenic H in Vesta's regolith
Thomas H. Prettyman, David W. Mittlefehldt, Naoyuki Yamashita, David J. Lawrence, Andrew W. Beck, William C. Feldman, Timothy J. McCoy, Harry Y. McSween, Michael J. Toplis, Timothy N. Titus, Pasquale Tricarico, Robert C. Reedy, John S. Hendricks, Olivier Forni, Lucille Le Corre, Jian-Yang Li, Hugau Mizzon, Vishnu Reddy, Carol A. Raymond, Christopher T. Russell
2012, Science (338) 242-246
Using Dawn’s Gamma Ray and Neutron Detector, we tested models of Vesta’s evolution based on studies of howardite, eucrite, and diogenite (HED) meteorites. Global Fe/O and Fe/Si ratios are consistent with HED compositions. Neutron measurements confirm that a thick, diogenitic lower crust is exposed in the Rheasilvia basin, which is...
A meeting of the waters: interdisciplinary challenges and opportunities in tidal rivers
Scott H. Ensign, Gregory B. Noe, Cliff R. Hupp, Sergio Fagherazzi
2012, Eos, Transactions, American Geophysical Union (95) 455-456
At the interface of estuarine tides and freshwater rivers lie wetland and aquatic ecosystems, which experience dramatic effects of sea level rise. There, nontidal channels and riparian floodplains are transforming into tidal ecosystems, and tidal freshwater ecosystems are receiving increasing salinity. These river-floodplain systems have both fluvial characteristics, including meandering...
Ecology of bison, elk, and vegetation in an arid ecosystem
Kathryn A. Schoenecker
2012, Thesis
Herbivory has profound effects on vegetation production and structure in many different plant communities. The influence of herbivory on plants and ultimately ecosystem processes is shaped by the types of plants consumed, the intensity of herbivory, the evolutionary history of grazing, and the availability of water and nutrients to plants....
Landsat-7 ETM+: 12 years on-orbit reflective-band radiometric performance
B. L. Markham, M.O. Haque, J. A. Barsi, E. Micijevic, D. L. Helder, K. J. Thome, David Aaron, J. S. Czapla-Myers
2012, IEEE Transactions on Geoscience and Remote Sensing (50) 2056-2062
The Landsat-7 ETM+ sensor has been operating on orbit for more than 12 years, and characterizations of its performance have been ongoing over this period. In general, the radiometric performance of the instrument has been remarkably stable: 1) noise performance has degraded by 2% or less overall, with a few...
Biogeochemistry: unexpected uptake
Jayne Belnap
2012, Nature Geoscience (5) 443-444
Lichens, cyanobacteria, mosses and algae coat many terrestrial surfaces. These biological covers turn out to play an important role in the global cycling of carbon and nitrogen....
Spot-mapping underestimates song-territory size and use of mature forest by breeding golden-winged warblers in Minnesota, USA
Henry M. Streby, John P. Loegering, David E. Andersen
2012, Wildlife Society Bulletin (36) 40-46
Studies of songbird breeding habitat often compare habitat characteristics of used and unused areas. Although there is usually meticulous effort to precisely and consistently measure habitat characteristics, accuracy of methods for estimating which areas are used versus which are unused by birds remains generally untested. To examine accuracy of spot-mapping...
Source characterization of near-surface chemical explosions at SAFOD
Fred F. Pollitz, Justin Rubinstein, William Ellsworth
2012, Bulletin of the Seismological Society of America (102) 1348-1360
A series of near‐surface chemical explosions conducted at the San Andreas Fault Observatory at Depth (SAFOD) main hole were recorded by high‐frequency downhole receiver arrays in April 2005. These seismic recordings at depths ranging from the surface to 2.3 km constrain the shallow velocity and attenuation structure as well as...
Multiple functions of a multi-component mating pheromone in sea lamprey Petromyzon marinus
N.S. Johnson, S.-S. Yun, T.J. Buchinger, W. Li
2012, Journal of Fish Biology (80) 538-554
The role of the C24 sulphate in the mating pheromone component, 7α,12α,24-trihydroxy-5α-cholan-3-one 24-sulphate (3kPZS), to specifically induce upstream movement in ovulated female sea lampreys Petromyzon marinus was investigated. 7α,12α-dihydroxy-5α-cholan-3-one 24-oic acid (3kACA), a structurally similar bile acid released by spermiated males, but lacking the C24 sulphate ester, was tested in...
Nearshore hydrodynamics as loading and forcing factors for Escherichia coli contamination at an embayed beach
Zhongfu Ge, Richard L. Whitman, Meredith B. Nevers, Mantha S. Phanikumar, Muruleedhara N. Byappanahalli
2012, Limnology and Oceanography (57) 362-381
Numerical simulations of the transport and fate of Escherichia coli were conducted at Chicago's 63rd Street Beach, an embayed beach that had the highest mean E. coli concentration among 23 similar Lake Michigan beaches during summer months of 2000-2005, in order to find the cause for the high bacterial contamination....
Mapping critical loads of nitrogen deposition for aquatic ecosystems in the Rocky Mountains, USA
Leora Nanus, David W. Clow, Jasmine E. Saros, Verlin C. Stephens, Donald H. Campbell
2012, Environmental Pollution (166) 125-135
Spatially explicit estimates of critical loads of nitrogen (N) deposition (CLNdep) for nutrient enrichment in aquatic ecosystems were developed for the Rocky Mountains, USA, using a geostatistical approach. The lowest CLNdep estimates (−1 yr−1) occurred in high-elevation basins with steep slopes, sparse vegetation, and abundance...
Effects of supplemental feeding and aggregation on fecal glucocorticoid metabolite concentrations in elk
Victoria E. Forristal, Scott Creel, Mark L. Taper, Brandon M. Scurlock, Paul C. Cross
2012, Journal of Wildlife Management (76) 76-4
Habitat modifications and supplemental feeding artificially aggregate some wildlife populations, with potential impacts upon contact and parasite transmission rates. Less well recognized, however, is how increased aggregation may affect wildlife physiology. Crowding has been shown to induce stress responses, and increased glucocorticoid (GC) concentrations can reduce immune function and increase...
Kaolin
R.L. Virta
2012, Mining Engineering (64) 70-71
Fifteen companies mined kaolin in nine states in 2011. Production, on the basis of preliminary data, was estimated to be 5.48 Mt (6.04 million st) valued at $822 million, an increase from 5.42 Mt (5.97 million st) valued at $788 million in 2010. Production in Georgia, the top producing state,...
Hotspot: the Snake River Geothermal Drilling Project--initial report
J.W. Shervais, D. Nielson, T. Lachmar, E. H. Christiansen, L. Morgan, Wayne C. Shanks, C. Delahunty, D.R. Schmitt, L.M. Liberty, D.D. Blackwell, J. M. Glen, J.A. Kessler, K.E. Potter, M.M. Jean, C.J. Sant, T. Freeman
2012, Geothermal Resources Council Transactions (36) 767-772
The Snake River volcanic province (SRP) overlies a thermal anomaly that extends deep into the mantle; it represents one of the highest heat flow provinces in North America. The primary goal of this project is to evaluate geothermal potential in three distinct settings: (1) Kimama site: inferred high sub-aquifer geothermal...
Impact of the Deepwater Horizon oil spill on a deep-water coral community in the Gulf of Mexico
Helen K. White, Pen-Yuan Hsing, Walter Cho, Timothy M. Shank, Erik E. Cordes, Andrea M. Quattrini, Robert K. Nelson, Richard Camilli, Amanda W.J. Demopoulos, Christopher R. German, James M. Brooks, Harry H. Roberts, William Shedd, Christopher M. Reddy, Charles R. Fisher
2012, PNAS (109) 20303-20308
To assess the potential impact of the Deepwater Horizon oil spill on offshore ecosystems, 11 sites hosting deep-water coral communities were examined 3 to 4 mo after the well was capped. Healthy coral communities were observed at all sites >20 km from the Macondo well, including seven sites previously visited...
Shale Gas Development and Brook Trout: Scaling Best Management Practices to Anticipate Cumulative Effects
David Smith, Craig D. Snyder, Nathaniel P. Hitt, John A. Young, Stephen P. Faulkner
2012, Environmental Practice (14) 366-381
Shale gas development may involve trade-offs between energy development and benefits provided by natural ecosystems. However, current best management practices (BMPs) focus on mitigating localized ecological degradation. We review evidence for cumulative effects of natural gas development on brook trout (Salvelinus fontinalis) and conclude that BMPs should account for potential...
Assessing California groundwater susceptibility using trace concentrations of halogenated volatile organic compounds
Daniel A. Deeds, Justin T. Kulongoski, Kenneth Belitz
2012, Environmental Science & Technology (46) 13128-13135
Twenty-four halogenated volatile organic compounds (hVOCs) and SF6 were measured in groundwater samples collected from 312 wells across California at concentrations as low as 10–12 grams per kilogram groundwater. The hVOCs detected are predominately anthropogenic (i.e., “ahVOCs”) and as such their distribution delineates where groundwaters are impacted and susceptible to...
Assessing sloth bears as surrogates for carnivore conservation in Sri Lanka
Shyamala Ratnayeke, Frank T. van Manen
2012, Ursus (23) 206-217
Bears are large, charismatic mammals whose presence often garners conservation attention. Because healthy bear populations typically require large, contiguous areas of habitat, land conservation actions often are assumed to benefit co-occurring species, including other mammalian carnivores. However, we are not aware of an empirical test of this assumption. We used...
Context-dependent planktivory: interacting effects of turbidity and predation risk on adaptive foraging
Kevin L. Pangle, Timothy D. Malinich, David B. Bunnell, Dennis R. DeVries, Stuart A. Ludsin
2012, Ecosphere (3)
By shaping species interactions, adaptive phenotypic plasticity can profoundly influence ecosystems. Predicting such outcomes has proven difficult, however, owing in part to the dependence of plasticity on the environmental context. Of particular relevance are environmental factors that affect sensory performance in organisms in ways that alter the tradeoffs associated with...
Evidence of late-summer mating readiness and early sexual maturation in migratory tree-roosting bats found dead at wind turbines
P.M. Cryan, J.W. Jameson, E.F. Baerwald, C.K.R. Willis, R.M.R. Barclay, E.A. Snider, E.G. Crichton
2012, PLoS ONE (7)
Understanding animal mating systems is an important component of their conservation, yet the precise mating times for many species of bats are unknown. The aim of this study was to better understand the details and timing of reproductive events in species of bats that die most frequently at wind turbines...
A brief review of the construction aggregates market
Jason Christopher Willett
2012, Stone, Sand & Gravel Review (2012) 25-27
The U.S. Geological Survey defines the construction aggregates industry as those companies that mine and process crushed stone and/or construction sand and gravel. Aggregates have been used from the earliest times of our civilization for a variety of purposes - construction being the major use. As construction aggregates, crushed stone...