Genetic reconstruction of a bullfrog invasion to elucidate vectors of introduction and secondary spread
Pauline L. Kamath, Adam J. Sepulveda, Megan J. Layhee
2016, Ecology and Evolution (6) 5221-5233
Reconstructing historical colonization pathways of an invasive species is critical for uncovering factors that determine invasion success and for designing management strategies. The American bullfrog (Lithobates catesbeianus) is endemic to eastern North America, but now has a global distribution and is considered to be one of the worst invaders in...
Characterizing supraglacial meltwater channel hydraulics on the Greenland Ice Sheet from in situ observations
Colin J. Gleason, Laurence C. Smith, Vena W. Chu, Carl J. Legleiter, Lincoln H. Pitcher, Brandon T. Overstreet, Asa K. Rennermalm, Richard R. Forster, Kang Yang
2016, Earth Surface Processes and Landforms (41) 2111-2122
Supraglacial rivers on the Greenland ice sheet (GrIS) transport large volumes of surface meltwater toward the ocean, yet have received relatively little direct research. This study presents field observations of channel width, depth, velocity, and water surface slope for nine supraglacial channels on the southwestern GrIS collected between 23 July...
Geographic distribution of genetic diversity in populations of Rio Grande Chub Gila pandora
Rene Galindo, Wade Wilson, Colleen A. Caldwell
2016, Conservation Genetics (17) 1081-1091
In the southwestern United States (US), the Rio Grande chub (Gila pandora) is state-listed as a fish species of greatest conservation need and federally listed as sensitive due to habitat alterations and competition with non-native fishes. Characterizing genetic diversity, genetic population structure, and effective number of breeders...
Geology and biology of the "Sticky Grounds," shelf-margin carbonate mounds, and mesophotic ecosystem in the eastern Gulf of Mexico
Stanley D. Locker, John K. Reed, Stephanie Farrington, Stacey Harter, Albert C. Hine, Shane Dunn
2016, Continental Shelf Research (125) 71-87
Shelf-margin carbonate mounds in water depths of 116–135 m in the eastern Gulf of Mexico along the central west Florida shelf were investigated using swath bathymetry, side-scan sonar, sub-bottom imaging, rock dredging, and submersible dives. These enigmatic structures, known to fisherman as the “Sticky Grounds”, trend along slope, are...
High concentrations of manganese and sulfur in deposits on Murray Ridge, Endeavour Crater, Mars
Raymond E. Arvidson, Steven W. Squyres, Richard V. Morris, Andrew H. Knoll, Ralf Gellert, Benton C. Clark, Jeffrey G. Catalano, Bradley L. Jolliff, Scott M. McLennan, Kenneth E. Herkenhoff, Scott VanBommel, David W. Mittelfehldt, John P. Grotzinger, Edward A. Guinness, Jeffrey R. Johnson, James F. Bell III, William H. Farrand, Nathan Stein, Valerie K. Fox, Matthew P. Golombek, Margaret A. G. Hinkle, Wendy M. Calvin, Paulo A. de Souza Jr.
2016, American Mineralogist (101) 1389-1405
Mars Reconnaissance Orbiter HiRISE images and Opportunity rover observations of the ~22 km wide Noachian age Endeavour Crater on Mars show that the rim and surrounding terrains were densely fractured during the impact crater-forming event. Fractures have also propagated upward into the overlying Burns formation sandstones. Opportunity’s observations show that...
Impact of formation water geochemistry and crude oil biodegradation on microbial methanogenesis
Jenna L. Shelton, Jennifer C. McIntosh, Peter D. Warwick, John E. McCray
2016, Organic Geochemistry (98) 105-117
Converting non-producible crude oil to CH4 via methanogenic crude oil biodegradation in oil reservoirs could serve as one way to increase our energy profile. Yet, field data supporting the direct relationship between methanogenesis and crude oil biodegradation are sparse. Indicators of methanogenesis, based on the formation water and gas geochemistry...
An association between a cusk eel (Bassozetus sp.) and a black coral (Schizopathes sp.) in the deep western Indian Ocean
Andrew R. Gates, Kirsty Morris, Daniel O.B. Jones, Kenneth J. Sulak
2016, Marine Biodiversity Records (47) 971-977
Detailed observations in the deep sea can reveal previously unknown behaviour, species interactions and fine-scale habitat heterogeneity. Here, the first in situ images of the black coral Schizopathes sp. (Anthozoa: Antipatharia) in the deep western Indian Ocean have been obtained from remotely operated vehicle video footage and time-lapse photography. In...
Estimation of peak discharge quantiles for selected annual exceedance probabilities in northeastern Illinois
Thomas M. Over, Riki J. Saito, Andrea G. Veilleux, Padraic S. O’Shea, Jennifer B. Sharpe, David T. Soong, Audrey L. Ishii
2016, Scientific Investigations Report 2016-5050
This report provides two sets of equations for estimating peak discharge quantiles at annual exceedance probabilities (AEPs) of 0.50, 0.20, 0.10, 0.04, 0.02, 0.01, 0.005, and 0.002 (recurrence intervals of 2, 5, 10, 25, 50, 100, 200, and 500 years, respectively) for watersheds in Illinois based on annual maximum peak...
Regional differences in upland forest to developed (urban) land cover conversions in the conterminous U.S., 1973–2011
Roger F. Auch, Mark A. Drummond, George Z. Xian, Kristi Sayler, William Acevedo, Janis Taylor
2016, Forests (7)
In this U.S. Geological Survey study of forest land cover across the conterminous U.S. (CONUS), specific proportions and rates of forest conversion to developed (urban) land were assessed on an ecoregional basis. The study period was divided into six time intervals between 1973 and 2011. Forest land cover was the...
Loss of genetic diversity and increased subdivision in an endemic Alpine Stonefly threatened by climate change
Steve Jordan, J. Joseph Giersch, Clint C. Muhlfeld, Scott Hotalling, Liz Fanning, Tyler H. Tappenbeck, Gordon Luikart
2016, PLoS ONE (11)
Much remains unknown about the genetic status and population connectivity of high-elevation and high-latitude freshwater invertebrates, which often persist near snow and ice masses that are disappearing due to climate change. Here we report on the conservation genetics of the meltwater stonefly Lednia tumana (Ricker) of Montana, USA, a cold-water...
Jaguar taxonomy and genetic diversity for southern Arizona, United States, and Sonora, Mexico
Melanie Culver, Alexander Ochoa Hein
2016, Open-File Report 2016-1109
Executive SummaryThe jaguar is the largest Neotropical felid and the only extant representative of the genus Panthera in the Americas. In recorded history, the jaguars range has extended from the Southern United States, throughout Mexico, to Central and South America, and they occupy a wide variety of habitats. A previous...
Reconsidering earthquake scaling
Joan S. Gomberg, Aaron G. Wech, Kenneth Creager, K. Obara, Duncan Agnew
2016, Geophysical Research Letters (43) 6243-6251
The relationship (scaling) between scalar moment, M0, and duration, T, potentially provides key constraints on the physics governing fault slip. The prevailing interpretation of M0-T observations proposes different scaling for fast (earthquakes) and slow (mostly aseismic) slip populations and thus fundamentally different driving mechanisms. We show that a single model of slip events within...
Small-scale barriers mitigate desertification processes and enhance plant recruitment in a degraded semiarid grassland
Stephen E. Fick, Cheryl E. Decker, Michael C. Duniway, Mark E. Miller
2016, Ecosphere (7)
Anthropogenic desertification is a problem that plagues drylands globally; however, the factors which maintain degraded states are often unclear. In Canyonlands National Park on the Colorado Plateau of southeastern Utah, many degraded grasslands have not recovered structure and function >40 yr after release from livestock grazing pressure, necessitating active...
Groundwater-flow model for the Wood River Valley aquifer system, south-central Idaho
Jason C. Fisher, James R. Bartolino, Allan H. Wylie, Jennifer Sukow, Michael McVay
2016, Scientific Investigations Report 2016-5080
A three-dimensional numerical model of groundwater flow was developed for the Wood River Valley (WRV) aquifer system, Idaho, to evaluate groundwater and surface-water availability at the regional scale. This mountain valley is located in Blaine County and has a drainage area of about 2,300 square kilometers (888 square miles). The...
Threshold sensitivity of shallow Arctic lakes and sublake permafrost to changing winter climate
Christopher D. Arp, Benjamin M. Jones, Guido Grosse, Allen C. Bondurant, Vladimir E. Romanovksy, Kenneth M. Hinkel, Andrew D. Parsekian
2016, Geophysical Research Letters (43) 6358-6365
Interactions and feedbacks between abundant surface waters and permafrost fundamentally shape lowland Arctic landscapes. Sublake permafrost is maintained when the maximum ice thickness (MIT) exceeds lake depth and mean annual bed temperatures (MABTs) remain below freezing. However, declining MIT since the 1970s is likely causing talik development below...
A spatially explicit suspended-sediment load model for western Oregon
Daniel R. Wise, Jim O’Connor
2016, Scientific Investigations Report 2016-5079
We calibrated the watershed model SPARROW (Spatially Referenced Regressions on Watershed attributes) to give estimates of suspended-sediment loads for western Oregon and parts of northwestern California. Estimates of suspended-sediment loads were derived from a nonlinear least squares regression that related explanatory variables representing landscape and transport conditions to measured suspended-sediment...
Estimating peak-flow frequency statistics for selected gaged and ungaged sites in naturally flowing streams and rivers in Idaho
Molly S. Wood, Ryan L. Fosness, Kenneth D. Skinner, Andrea G. Veilleux
2016, Scientific Investigations Report 2016-5083
The U.S. Geological Survey, in cooperation with the Idaho Transportation Department, updated regional regression equations to estimate peak-flow statistics at ungaged sites on Idaho streams using recent streamflow (flow) data and new statistical techniques. Peak-flow statistics with 80-, 67-, 50-, 43-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent annual...
The role of habitat filtering in the leaf economics spectrum and plant susceptibility to pathogen infection
Miranda E Welsh, James P. Cronin, Charles E. Mitchell
2016, Journal of Ecology (104) 1768-1777
1.The Leaf Economics Spectrum (LES) describes global covariation in the traits of plant leaves. The LES is thought to arise from biophysical constraints and habitat filtering (ecological selection against unfit trait combinations along environmental gradients). However, the role of habitat filtering in generating the LES has not been tested experimentally. 2.If...
The Maryland Coastal Plain Aquifer Information System: A GIS-based tool for assessing groundwater resources
David C. Andreasen, Mark R. Nardi, Andrew W. Staley, Grufron Achmad, John W. Grace
2016, Special Paper of the Geological Society of America (520) 159-170
Groundwater is the source of drinking water for ∼1.4 million people in the Coastal Plain Province of Maryland (USA). In addition, groundwater is essential for commercial, industrial, and agricultural uses. Approximately 0.757 × 109 L d–1 (200 million gallons/d) were withdrawn in 2010. As a result of decades of withdrawals...
Mercury risk to avian piscivores across western United States and Canada
Allyson K. Jackson, David C. Evers, Collin A. Eagles-Smith, Joshua T. Ackerman, James J. Willacker, John E. Elliott, Jesse M. Lepak, Stacy S. Vander Pol, Colleen E. Bryan
2016, Science of the Total Environment (568) 685-696
The widespread distribution of mercury (Hg) threatens wildlife health, particularly piscivorous birds. Western North America is a diverse region that provides critical habitat to many piscivorous bird species, and also has a well-documented history of mercury contamination from legacy mining and atmospheric deposition. The diversity of landscapes in the west...
Pre/post-closure assessment of groundwater pharmaceutical fate in a wastewater‑facility-impacted stream reach
Paul M. Bradley, Larry B. Barber, Jimmy M. Clark, Joseph W. Duris, William T. Foreman, Edward T. Furlong, Carrie E. Givens, Laura E. Hubbard, Kasey J. Hutchinson, Celeste A. Journey, Steffanie H. Keefe, Dana W. Kolpin
2016, Science of the Total Environment (568) 916-925
Pharmaceutical contamination of contiguous groundwater is a substantial concern in wastewater-impacted streams, due to ubiquity in effluent, high aqueous mobility, designed bioactivity, and to effluent-driven hydraulic gradients. Wastewater treatment facility (WWTF) closures are rare environmental remediation events; offering unique insights into contaminant persistence, long-term wastewater impacts, and ecosystem recovery processes....
Growth rates and ages of deep-sea corals impacted by the Deepwater Horizon oil spill
Nancy G. Prouty, Charles R. Fisher, Amanda W.J. Demopoulos, Ellen R. M. Druffel
2016, Deep-Sea Research Part II: Topical Studies in Oceanography (129) 212
The impact of the April 2010 Deepwater Horizon (DWH) spill on deep-sea coral communities in the Gulf of Mexico (GoM) is still under investigation, as is the potential for these communities to recover. Impacts from the spill include observation of corals covered with flocculent material, with bare skeleton, excessive mucous...
Inferring river bathymetry via Image-to-Depth Quantile Transformation (IDQT)
Carl J. Legleiter
2016, Water Resources Research (52) 3722-3741
Conventional, regression-based methods of inferring depth from passive optical image data undermine the advantages of remote sensing for characterizing river systems. This study introduces and evaluates a more flexible framework, Image-to-Depth Quantile Transformation (IDQT), that involves linking the frequency distribution of pixel values to that of depth. In addition, a...
Storeria occipitomaculata obscura (Florida red-bellied snake)
Lindy J. Muse, Brad M. Glorioso, Chandler A. R. Eaglestone
2016, Herpetological Review (47) 266-266
USA: LOUISIANA: Vermilion Parish: Palmetto Island State Park (29.86335°N, 92.14848°W; WGS 84). 19 February 2016. Lindy J. Muse. Verified by Jeff Boundy. Florida Museum of Natural History (UF 177730, photo voucher). New parish record (Dundee and Rossman 1989. The Amphibians and Reptiles of Louisiana. Louisiana State University Press, Baton Rouge,...
A synthesis of the basal thermal state of the Greenland Ice Sheet
Joseph A MacGregor, Mark A Fahnestock, Ginny A Catania, Andy Aschwanden, Gary D. Clow, William T. Colgan, Prasad S. Gogineni, Mathieu Morlighem, Sophie M .J. Nowicki, John D Paden, Stephen F. Price, Helene Seroussi
2016, Journal of Geophysical Research F: Earth Surface (121) 1328-1350
The basal thermal state of an ice sheet (frozen or thawed) is an important control upon its evolution, dynamics and response to external forcings. However, this state can only be observed directly within sparse boreholes or inferred conclusively from the presence of subglacial lakes. Here we synthesize spatially extensive inferences...
