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Page 1299, results 32451 - 32475

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Multiscale habitat selection of wetland birds in the northern Gulf Coast
Bradley A. Pickens, Sammy L. King
2014, Estuaries and Coasts (37) 1301-1311
The spatial scale of habitat selection has become a prominent concept in ecology, but has received less attention in coastal ecology. In coastal marshes, broad-scale marsh types are defined by vegetation composition over thousands of hectares, water-level management is applied over hundreds of hectares, and fine-scale habitat is depicted by...
Conserving Prairie Pothole Region wetlands and surrounding grasslands: evaluating effects on amphibians
David M. Mushet, Jordan L. Neau
2014, Report
The maintenance of viable and genetically diverse populations of amphibians in the Prairie Pothole Region of the United States depends on upland as well as wetland over-wintering and landscape level habitat features.Prairie pothole wetlands provide important amphibian breeding habitat while grasslands surrounding these wetlands provide foraging habitat for adults, overwintering...
Phenological adjustment in arctic bird species: relative importance of snow melt and ecological factors
Joseph R. Liebezeit, K. E. B. Gurney, Michael E. Budde, Steve Zack, David H. Ward
2014, Polar Biology (37) 1309-1320
Previous studies have documented advancement in clutch initiation dates (CIDs) in response to climate change, most notably for temperate-breeding passerines. Despite accelerated climate change in the Arctic, few studies have examined nest phenology shifts in arctic breeding species. We investigated whether CIDs have advanced for the most abundant breeding shorebird...
Experimental test of theory for the stability of partially saturated vertical cut slopes
Michael M. Morse, N. Lu, Alexandra Wayllace, Jonathan W. Godt, W.A. Take
2014, Journal of Geotechnical and Geoenvironmental Engineering (140)
This paper extends Culmann's vertical-cut analysis to unsaturated soils. To test the extended theory, unsaturated sand was compacted to a uniform porosity and moisture content in a laboratory apparatus. A sliding door that extended the height of the free face of the slope was lowered until the vertical cut failed....
Northern bobwhite predator avoidance behavior in response to varying types of threat
R.A. Perkins, Clint W. Boal, Dale Rollins, R. Perez
2014, Journal of Wildlife Management (78) 1272-1281
The flight behavior and cover use of northern bobwhite (Colinus virginianus) have been examined in several studies, but the current data lack quantitative measures of how bobwhites respond to natural threats. We examined aspects of bobwhite behavior in response to 4 threat categories: researcher, hunter, raptor, and mammal. We found...
Inorganic elements in green sea turtles (Chelonia mydas): relationships among external and internal tissues
Derek R. Faust, Michael J. Hooper, George P. Cobb, Melanie Barnes, Donna Shaver, Shauna Ertolacci, Philip N. Smith
2014, Environmental Toxicology and Chemistry (33) 2020-2027
Inorganic elements from anthropogenic sources have entered marine environments worldwide and are detectable in marine organisms, including sea turtles. Threatened and endangered classifications of sea turtles have heretofore made assessments of contaminant concentrations difficult because of regulatory restrictions on obtaining samples using nonlethal techniques. In the present study, claw and...
Indo-Pacific sea surface temperature influences on failed consecutive rainy seasons over eastern Africa
Andrew Hoell, Christopher C. Funk
2014, Climate Dynamics (43) 1645-1660
Rainfall over eastern Africa (10°S–10°N; 35°E–50°E) is bimodal, with seasonal maxima during the "long rains" of March–April–May (MAM) and the "short rains" of October–November–December (OND). Below average precipitation during consecutive long and short rains seasons over eastern Africa can have devastating long-term impacts on water availability and agriculture. Here, we...
Quaternary ostracode and foraminiferal biostratigraphy and paleoceanography in the western Arctic Ocean
Thomas M. Cronin, Lauren H. DeNinno, L.V. Polyak, Emma K. Caverly, Richard Z. Poore, Alec R. Brenner, J. Rodriguez-Lazaro, R.E. Marzen
2014, Marine Micropaleontology (111) 118-133
The stratigraphic distributions of ostracodes and selected calcareous benthic and planktic foraminiferal species were studied in sediment cores from ~ 700 to 2700 m water depth on the Northwind, Mendeleev, and Lomonosov Ridges in the western Arctic Ocean. Microfaunal records in most cores cover mid- to late Quaternary sediments deposited in the...
Use of isotopic sulfur to determine whitebark pine consumption by Yellowstone bears: a reassessment
Charles C. Schwartz, Justin E. Teisberg, Jennifer K. Fortin, Mark A. Haroldson, Christopher Servheen, Charles T. Robbins, Frank T. van Manen
2014, Wildlife Society Bulletin (38) 664-670
Use of naturally occurring stable isotopes to estimate assimilated diet of bears is one of the single greatest breakthroughs in nutritional ecology during the past 20 years. Previous research in the Greater Yellowstone Ecosystem (GYE), USA, established a positive relationship between the stable isotope of sulfur (δ34S) and consumption of...
Sampling from living organisms
Christina A. Kellogg
2014, Book chapter, Biofouling methods
Living organisms, unlike inanimate surfaces, seem to exert some control over their surface microbiota, in many cases maintaining conserved, species-specific microbial communities. Microbial ecologists seek to characterize and identify these microbes to understand the roles they are playing in the larger organism's biology....
The effect of call libraries and acoustic filters on the identification of bat echolocation
Matthew Clement, Kevin L Murray, Donald I Solick, Jeffrey C Gruver
2014, Ecology and Evolution (4) 3482-3493
Quantitative methods for species identification are commonly used in acoustic surveys for animals. While various identification models have been studied extensively, there has been little study of methods for selecting calls prior to modeling or methods for validating results after modeling. We obtained two call libraries with a combined 1556...
Combining demographic and genetic factors to assess population vulnerability in stream species
Erin L. Landguth, Clint C. Muhlfeld, Leslie W. Jones, Robin S. Waples, Diane Whited, Winsor H. Lowe, John Lucotch, Helen Neville, Gordon Luikart
2014, Ecological Applications (24) 1505-1524
Accelerating climate change and other cumulative stressors create an urgent need to understand the influence of environmental variation and landscape features on the connectivity and vulnerability of freshwater species. Here, we introduce a novel modeling framework for aquatic systems that integrates spatially explicit, individual‐based, demographic and genetic (demogenetic) assessments with...
A ternary age-mixing model to explain contaminant occurrence in a deep supply well
Bryant C. Jurgens, Laura M. Bexfield, Sandra M. Eberts
2014, Groundwater (52) 25-39
The age distribution of water from a public-supply well in a deep alluvial aquifer was estimated and used to help explain arsenic variability in the water. The age distribution was computed using a ternary mixing model that combines three lumped parameter models of advection-dispersion transport of environmental tracers, which represent...
Temporal changes in taxonomic and functional diversity of fish assemblages downstream from mountaintop mining
Nathaniel P. Hitt, Douglas B. Chambers
2014, Freshwater Science (33) 915-926
Mountaintop mining (MTM) affects chemical, physical, and hydrological properties of receiving streams, but the long-term consequences for fish-assemblage structure and function are poorly understood. We sampled stream fish assemblages using electrofishing techniques in MTM exposure sites and reference sites within the Guyandotte River basin, USA, during 2010–2011. We calculated indices...
Tidal and seasonal effects on survival rates of the endangered California clapper rail: Does invasive Spartina facilitate greater survival in a dynamic environment?
Cory T. Overton, Michael L. Casazza, John Y. Takekawa, Donald R. Strong, Marcel Holyoak
2014, Biological Invasions (16) 1897-1914
Invasive species frequently degrade habitats, disturb ecosystem processes, and can increase the likelihood of extinction of imperiled populations. However, novel or enhanced functions provided by invading species may reduce the impact of processes that limit populations. It is important to recognize how invasive species benefit endangered species to determine overall...
In situ and laboratory toxicity of coalbed natural gas produced waters with elevated sodium bicarbonate
Aida M. Farag, David D. Harper, Don Skaar
2014, Environmental Toxicology and Chemistry (33) 2086-2093
Some tributaries in the Powder River Structural Basin, USA, were historically ephemeral, but now contain water year round as a result of discharge of coalbed natural gas (CBNG)-produced waters. This presented the opportunity to study field sites with 100% effluent water with elevated concentrations of sodium bicarbonate. In situ experiments,...
Succession of Laramide magmatic and magmatic-hydrothermal events in the Patagonia Mountains, Santa Cruz County, Arizona
Peter Vikre, Frederick T. Graybeal, Robert J. Fleck, Mark D. Barton, Eric Seedorff
2014, Economic Geology (109) 1667-1704
This investigation of the space-time progression of magmatism and hydrothermal activity in the Patagonia Mountains of southern Arizona is based on field and paragenetic relationships, and on U-Pb and 40Ar/39Ar geochronology of igneous and hydrothermal minerals. The Patagonia Mountains consist of Precambrian, Paleozoic, and Mesozoic sedimentary, granitic, and volcanic rocks, Laramide...
Partitioning the non‑consumptive effects of predators on preywith complex life histories
Jon M. Davenport, Blake R. Hossack, Winsor H. Lowe
2014, Oecologia (176) 149-155
Non-consumptive effects (NCEs) of predators on prey can be as strong as consumptive effects (CEs) and may be driven by numerous mechanisms, including predator characteristics. Previous work has highlighted the importance of predator characteristics in predicting NCEs, but has not addressed how complex life histories of prey could mediate predator...
Characterization of Lone Pine, California, tremolite asbestos and preparation of research material
Martin Harper, Bradley S. Van Gosen, Owen S Crankshaw, Stacy S Doorn, J. Todd Ennis, Sara E Harrison
2014, The Annals of Occupational Hygiene (59) 91-103
Well-characterized amphibole asbestos mineral samples are required for use as analytical standards and in future research projects. Currently, the National Institute for Standards and Technology Standard Reference Material samples of asbestos are listed as ‘Discontinued’. The National Institute for Occupational Safety and Health (NIOSH) has a goal under the Asbestos...
Analysis of regional scale risk to whirling disease in populations of Colorado and Rio Grande cutthroat trout using Bayesian belief network model
Kimberley Kolb Ayre, Colleen A. Caldwell, Jonah Stinson, Wayne G. Landis
2014, Risk Analysis (34) 1589-1605
Introduction and spread of the parasite Myxobolus cerebralis, the causative agent of whirling disease, has contributed to the collapse of wild trout populations throughout the intermountain west. Of concern is the risk the disease may have on conservation and recovery of native cutthroat trout. We employed a Bayesian belief network to...
Pollen dispersal by catapult: Experiments of Lyman J. Briggs on the flower of mountain laurel
John R. Nimmo, Paula M. Hermann, M.B. Kirkham, Edward R. Landa
2014, Physics in Perspective (16) 371-389
The flower of Kalmia latifolia L. employs a catapult mechanism that flings its pollen to considerable distances. Physicist Lyman J. Briggs investigated this phenomenon in the 1950s after retiring as longtime director of the National Bureau of Standards, attempting to explain how hydromechanical effects inside the flower’s stamen could make...
Age-specific survival of male golden-cheeked warblers on the Fort Hood Military Reservation, Texas
Adam Duarte, James E. Hines, James D. Nichols, Jeffrey S. Hatfield, Floyd W. Weckerly
2014, Avian Conservation and Ecology (9)
Population models are essential components of large-scale conservation and management plans for the federally endangered Golden-cheeked Warbler (Setophaga chrysoparia; hereafter GCWA). However, existing models are based on vital rate estimates calculated using relatively small data sets that are now more than a decade old. We estimated more current, precise adult...
List of recent land mammals from Mexico, 2014
Jose Ramirez-Pulido, Noe Gonzalez-Ruiz, Alfred L. Gardner, Joaquin Arroyo-Cabrales
2014, Book
We provide an updated list of the Recent land mammals of Mexico and include information on the taxonomy of certain species, and where appropriate, the endemic and threatened status of all species listed. Several taxonomic and nomenclatural changes have been made since publication of the last list of the Mexican...
Variation in the terrestrial isotopic composition and atomic weight of argon
John Karl Böhlke
2014, Pure and Applied Chemistry (86) 1421-1432
The isotopic composition and atomic weight of argon (Ar) are variable in terrestrial materials. Those variations are a source of uncertainty in the assignment of standard properties for Ar, but they provide useful information in many areas of science. Variations in the stable isotopic composition and atomic weight of Ar...