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Page 895, results 22351 - 22375

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Book review: Behavioral ecology of the eastern red-backed salamander: 50 years of research
Susan C. Walls, Joseph C. Mitchell
2017, Herpetological Review (48) 468-470
In commemoration of the 100th anniversary of the British Ecological Society, Sutherland et al. (2013) identified 100 questions of fundamental significance in “pure” (i.e., not applied) ecology. A somewhat unexpected outcome of these authors’ exercise was the realization that, after 100 years of comprehensive, intensive scientific research, there remained “profound...
Human presence diminishes the importance of climate in driving fire activity across the United States
Alexandra D. Syphard, Jon E. Keeley, Anne Hopkins Pfaff, Ken Ferschweiler
2017, PNAS (114) 13750-13755
Growing human and ecological costs due to increasing wildfire are an urgent concern in policy and management, particularly given projections of worsening fire conditions under climate change. Thus, understanding the relationship between climatic variation and fire activity is a critically important scientific question. Different factors limit fire behavior in different...
Co-producing simulation models to inform resource management: a case study from southwest South Dakota
Brian W. Miller, Amy J. Symstad, Leonardo Frid, Nicholas A. Fisichelli, Gregor W. Schuurman
2017, Ecosphere (8)
Simulation models can represent complexities of the real world and serve as virtual laboratories for asking “what if…?” questions about how systems might respond to different scenarios. However, simulation models have limited relevance to real-world applications when designed without input from people who could use the simulated scenarios to inform...
Declining survival of black brant from subarctic and arctic breeding areas
Alan G. Leach, David H. Ward, James S. Sedinger, Mark S. Lindberg, W. Sean Boyd, Jerry W. Hupp, Robert J. Ritchie
2017, Journal of Wildlife Management (81) 1210-1218
Since the mid 1990s, the number of black brant (Branta bernicla nigricans; brant) nests on the Yukon‐Kuskokwim Delta (YKD), Alaska, USA, the historically predominant breeding area of brant, has declined steadily. This has caused researchers and managers to question if arctic breeding populations can compensate for the reduction in brant...
Linking fluvial and aeolian morphodynamics in the Grand Canyon, USA
Alan Kasprak, Sara G. Bangen, Daniel D. Buscombe, Joshua Caster, Amy E. East, Paul E. Grams, Joel B. Sankey
2017, Conference Paper, RCEM 2017 - Back to Italy: The 10th Symposium on River, Coastal and Estuarine Morphodynamics
In river valleys, fluvial and upland landscapes are intrinsically linked through sediment exchange between the active channel, near-channel fluvial deposits, and higher elevation upland deposits. During floods, sediment is transferred from channels to low-elevation nearchannel deposits [Schmidt and Rubin, 1995]. Particularly in dryland river valleys, subsequent aeolian reworking of these...
The Southern Appalachian Brook Trout management conundrum: What should restoration look like in the 21st Century?
Matt A. Kulp, Shawna Mitchell, David C. Kazyak, Bernard R. Kuhajda, Jason Henegar, T. Casey Weathers, Anna George, Joshua R. Ennen, Tim King
2017, Conference Paper, Proceedings of the wild trout XII symposium
Brook Trout Salvelinus fontinalis in the southern Appalachian portion of their range have been isolated in remote headwater systems for millennia. Recent genetic investigations indicate extremely low allelic diversity, heterozygosity and effective population sizes in many streams. In populations restored using multiple source stocks, limited introgression has been observed despite...
Characterization of microsatellite loci for the Gulf Coast waterdog (Necturus beyeri) using paired-end Illumina shotgun sequencing and cross-amplification in other Necturus
Jennifer Y. Lamb, Brian R. Kreiser, Hardin Waddle, Carl P. Qualls
2017, Herpetological Review (48) 458-763
Amphibians are one of the most threatened groups of vertebrates (Stuart et al. 2004; Wake and Vredenburg 2008), and the application of molecular techniques to amphibian ecology and genetics has dramatically improved our ability to conserve species and populations (see Shaffer et al. [2015] for review). Microsatellites, tandem repeats of...
Are nest boxes ecological traps for red-footed falcons Falco vespertinius at Naurzum
Todd E. Katzner, Alexander E. Bragin, Evgeny A. Bragin
2017, Conference Paper, Biological diversity of Asian Steppe: Proceedings of the III international scientific conference
Nest box programs are frequently implemented for conservation of cavity-nesting birds, but their effectiveness is rarely evaluated in comparison to birds not using nest boxes. In the European Palearctic, Red-Footed Falcon (Falco vespertinus) populations are both of high conservation concern and are strongly associated with nest box programs in heavily...
Born of fire: In search of volcanoes in U.S. national parks, four striking examples
Laura Walkup, Thomas Casadevall, Vincent L. Santucci
2017, Earth Sciences History (36) 197-244
Geologic features, particularly volcanic features, have been protected by the National Park Service since its inception. Some volcanic areas were nationally protected even before the National Park Service was established. The first national park, Yellowstone National Park, is one of the most widely known geothermal and volcanic areas in the...
Permafrost-related processes and recent response to climatic changes
Marina Leibman, Alexandr Kizyakov, Guido Grosse, Benjamin M. Jones, M. Torre Jorgenson, Mikhail Z. Kanevskiy
2017, Book chapter, Snow, water, ice and permafrost in the Arctic (SWIPA) 2017
Permafrost-related processes have direct and indirect consequences to northern environments, but the impacts are affected by complex interactions involving positive and negative feedbacks at the surface (Jorgenson et al. 2010), climatic trends and fluctuations (Romanovsky et al. 2010; Konishchev 2011), and terrain and ground ice conditions (French and Shur 2010,...
Implications of refining vertical resolution of hydraulic conductivity in the numerical modeling of groundwater flow to surface water, NAS Whiting Field, Florida
Eric D. Swain, Bruce G. Campbell, James Landmeyer
2017, Conference Paper, Fourth international symposium on bioremediation and sustainable environmental technologies
Naval Air Station Whiting Field is located near Milton, Florida and is one of the Navy's two primary pilot training bases. Commissioned in 1943, historic operations at Whiting Field generated industrial wastes that contaminated soil and the water-table aquifer. The Environmental Protection Agency placed Whiting Field on the Superfund program’s...
Application of organic petrology in high maturity shale gas systems
Paul C. Hackley
2017, Book chapter, Geology: Current and future developments
Application of incident light microscopy techniques for organic petrology in high temperature thermogenic shale gas systems demonstrates that solid bitumen is the dominant organic matter. Solid bitumen is retained as a residual conversion product as oil-prone kerogen cracks to hydrocarbons or occurs from the cracking of once liquid oil. Oil-prone...
Preliminary-assessment and upgrade of a groundwater flow model of the Seacoast Bedrock Aquifer, New Hampshire
Thomas J. Mack
2017, Conference Paper, Proceedings of the MODFLOW and more 2017 conference
In 2003 and 2004, the U.S. Geological Survey investigated the availability of groundwater resources in a 160-square mile area of coastal New Hampshire (Figure 1) using a regional groundwater flow model (Mack, 2009). At that time, population growth and increasing water demand prompted concern for the sustainability of the region’s...
Preliminary assessment of porphyry copper deposits in the Sierra Maestra, Cuba
Lukas Zurcher, Floyd Gray, Timothy Hayes, Greta J. Orris, Mark E. Gettings, Mark D. Cocker, Leila Gass
2017, Conference Paper, GEOCIENCIAS 2017 Proceedings volume "Memorias, Trabajos y Resumenes"
The U.S. Geological Survey’s “three-step” form of mineral-resource assessment was used to obtain a preliminary estimate of copper resources in undiscovered porphyry deposits of the Paleogene Sierra Maestra Arc. Results of this preliminary assessment suggest that a mean of 3.2 undiscovered deposits are likely present. This estimate is comparable to...
Severe Drought Impacts Female Pheasant Physiology in Southwest Nebraska
J. A. Laskowski, G. C. Bachman, Joseph J. Fontaine
2017, Prairie Naturalist (49) 57-65
In 2012, Nebraska experienced one of the worst droughts since the 1930s, accompanied by abnormally high temperatures. We studied the impacts of the 2012 summer drought on female ring-necked pheasant (Phasianus colchicus) body condition and baseline and stress-induced corticosterone concentrations (CORT). We hypothesized that drought conditions would reduce pheasant body...
Analysis of artificially matured shales with confocal laser scanning raman microscopy: Applications to organic matter characterization
Grant A. Myers, Kelsey Kehoe, Paul C. Hackley
2017, Conference Paper
Raman spectroscopy has been suggested as a method for characterizing the thermal maturity of rocks. The literature contains many empirical correlations between thermal maturity proxies, such as vitrinite reflectance (VRo) and pyrolysis-Tmax, with spectral metrics such as Raman peak-widths, peak-center positions, peak-areas and all manner of differences and ratios of...
Effects of isolation on ant assemblages depend on microhabitat
Xuan Chen, Benjamin Adams, Michael Layne, Christopher M. Swarzenski, David O. Norris, Linda Hooper-Bui
2017, Ecosphere (8) 1-12
How isolation affects biological communities is a fundamental question in ecology and conservation biology. Local diversity (α) and regional diversity (γ) are consistently lower in insular areas. The pattern of species turnover (β diversity) and the influence of isolation on competitive interactions are less predictable. Differences in communities across microhabitats...
Influence of lake surface area and total phosphorus on annual bluegill growth in small impoundments of central Georgia
Cecil A. Jennings, Aaron P. Sundmark
2017, Southeastern Naturalist (16) 546-566
The relationships between environmental variables and the growth rates of fishes are important and rapidly expanding topics in fisheries ecology. We used an informationtheoretic approach to evaluate the influence of lake surface area and total phosphorus on the age-specific growth rates of Lepomis macrochirus (Bluegill) in 6 small impoundments in central Georgia....
Spatial ecology and movement of reintroduced Canada lynx
Frances E. Buderman, Mevin Hooten, Jacob S. Ivan, Tanya Shenk
2017, Ecography (41) 126-139
Understanding movement behavior and identifying areas of landscape connectivity is critical for the conservation of many species. However, collecting fine‐scale movement data can be prohibitively time consuming and costly, especially for rare or endangered species, whereas existing data sets may provide the best available information on animal movement. Contemporary movement...
Population genetic structure and gene flow of Adélie penguins (Pygoscelis adeliae) breeding throughout the western Antarctic Peninsula
Kristen B. Gorman, Sandra L. Talbot, Sarah A. Sonsthagen, George K. Sage, Megan C. Gravley, Tony D. Williams, William R. Fraser
2017, Antarctic Science (29) 499-510
Adélie penguins (Pygoscelis adeliae) are responding to ocean–climate variability throughout the marine ecosystem of the western Antarctic Peninsula (WAP) where some breeding colonies have declined by 80%. Nuclear and mitochondrial DNA (mtDNA) markers were used to understand historical population genetic structure and gene flow given relatively recent and continuing reductions...
Occupancy and abundance of Eleutherodactylus wightmanae and E. brittoni along elevational gradients in west-central Puerto Rico
Kelen D. Monroe, Jaime A. Collazo, Krishna Pacifici, Brian J. Reich, Alberto R. Puente-Rolon, Adam J. Terando
2017, Caribbean Naturalist (40) 1-18
Populations of Eleutherodactylus species in Puerto Rico have declined in recent decades due to habitat loss and long-term climatic changes. The conservation of these habitat specialists requires an understanding of factors influencing their abundance and distribution, which at present is scant. We estimated occupancy probability and the probability of encountering ≥2 individuals of...
Comparison of the precision of age estimates generated from fin rays, scales, and otoliths of Blue Sucker
Matthew R. Acre, Celeste Alejandrez, Jessica East, Wade A. Massure, S. Miyazono, Jessica E. Pease, Elizabeth L. Roesler, H.M. Williams, Timothy B. Grabowski
2017, Southeastern Naturalist (16) 215-224
Evaluating the precision of age estimates generated by different readers and different calcified structures is an important part of generating reliable estimations of growth, recruitment, and mortality for fish populations. Understanding the potential loss of precision associated with using structures harvested without sacrificing individuals, such as...
CYP1A protein expression and catalytic activity in double-crested cormorants experimentally exposed to Deepwater Horizon Mississippi Canyon 252 oil
Courtney R. Alexander, Michael J. Hooper, Dave Cacela, Kim D. Smelker, Caleshia S. Calvin, Karen M. Dean, Steve J. Bursian, Fred L. Cunningham, Katie C. Hanson-Dorr, Katherine E. Horak, John P. Isanhart, Jane E. Link, Susan A. Shriner, Celine A.J. Godard-Codding
2017, Ecotoxicology and Environmental Safety (146) 68-75
Double-crested cormorants (Phalacrocorax auritus, DCCO) were orally exposed to Deepwater Horizon Mississippi Canyon 252 (DWH) oil to investigate oil-induced toxicological impacts. Livers were collected for multiple analyses including cytochrome P4501A (CYP1A) enzymatic activity and protein expression. CYP1A enzymatic activity was measured by alkoxyresorufin O-dealkylase (AROD) assays. Activities specific to the...