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Page 324, results 8076 - 8100

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Begging behavior as an honest signal of need and parent-offspring association during the post-fledging dependency period
Kayla L. Davis, Sarah M. Karpanty, Jeffrey A. Spendelow, Jonathan B. Cohen, Melissa A. Althouse, Katharine C Parsons, Cristin F. Luttazi
2019, Ecology and Evolution (9) 7497-7508
Honest signaling mechanisms can function to appropriate care to hungry offspring and avoid misdirected care of unrelated offspring. Begging, the behavior by which offspring solicit food and parental care, may be an honest signaling mechanism for need, as well as association of parents and offspring. Roseate terns (Sterna dougallii) exhibit...
Evaluating community-level response to management actions across a diverse Hawaiian forest bird community
Alban Guillaumet, Eben H. Paxton
2019, Ecological Applications (29) 1236-1246
Although species‐specific approaches are necessary to understand the dynamics of individual species composing a community, they do not offer a framework for making optimal management decisions at the community level. Here, we present a simple framework for comparing the response of entire communities to multiple management scenarios. Our approach uses...
Real-time monitoring of debris-flow velocity and mass deformation from field experiments with high sample rate lidar and video
Francis K. Rengers, Thomas Rapstine, Kate E. Allstadt, Michael Olsen, Michael Bunn, Richard M. Iverson, Jason W. Kean, Ben Leshchinsky, Matthew Logan, Mahyar Sharifi-Mood, Maciej K. Obryk, Joel B. Smith
2019, Conference Paper, Debris-flow hazards mitigation : mechanics, monitoring, modeling, and assessment ; proceedings of the Seventh International Conference on Debris-Flow Hazards Mitigation
Debris flows evolve in both time and space in complex ways, commonly starting as coherent failures but then quickly developing structures such as roll waves and surges. This process is readily observed, but difficult to study or quantify because of the speed at which it occurs. Many methods for studying...
Looking through the window of disturbance at post-wildfire debris-flow hazards
Luke McGuire, Francis K. Rengers, Jason W. Kean, Dennis M. Staley, Hui Tang, Ann Youberg
2019, Conference Paper, Debris-flow hazards mitigation : mechanics, monitoring, modeling, and assessment ; proceedings of the Seventh International Conference on Debris-Flow Hazards Mitigation
The extreme heat from wildfire alters soil properties and incinerates vegetation, leading to changes in infiltration capacity, ground cover, soil erodibility, and rainfall interception. These changes promote increases in runoff and sediment transport that increase the likelihood of runoff-generated debris flows. Over a period of several years, referred to as...
Topographic change detection at Chalk Cliffs, Colorado, USA, using Airborne LiDAR and UAS-based Structure-from-Motion photogrammetry
Katherine R Barnhart, Francis K. Rengers, Ghent Jessica N, Gregory E. Tucker, Jeffrey A. Coe, Jason W. Kean, Joel B. Smith, Dennis M. Staley, William Kleiber, Ashton M Wiens
2019, Conference Paper, Debris-flow hazards mitigation : mechanics, monitoring, modeling, and assessment ; proceedings of the Seventh International Conference on Debris-Flow Hazards Mitigation
The Chalk Cliffs debris-flow site is a small headwater catchment incised into highly fractured and hydrothermally altered quartz monzonite in a semi-arid climate. Over half of the extremely steep basin is exposed bedrock. Debris flows occur multiple times per year in response to rainstorm events, typically during the summer monsoon...
Airborne waveform lidar simulator using the radiative transfer of a laser pulse
Minsu Kim
2019, Applied Sciences (9)
An airborne lidar simulator creates a lidar point cloud from a simulated lidar system, flight parameters, and the terrain digital elevation model (DEM). At the basic level, the lidar simulator computes the range from a lidar system to the surface of a terrain using the geomatics lidar equation. The simple...
Spatially consistent high-resolution land surface temperature mosaics for thermophysical mapping of the Mojave Desert
Scott A Nowicki, Richard D. Inman, Todd Esque, Kenneth Nussear, Christopher S. Edwards
2019, Sensors (19)
Daytime and nighttime thermal infrared observations acquired by the ASTER and MODIS instruments onboard the NASA Terra spacecraft have produced a dataset that can be used to map thermophysical properties across large regions, which have implications on surface processes, thermal environments and habitat suitability for desert species. ASTER scenes acquired...
Hydrologic and hydraulic analyses of selected streams in Richland County, Ohio
Chad J. Ostheimer
2019, Scientific Investigations Report 2019-5011
Hydrologic and hydraulic analyses were done for selected reaches of Clear Fork Mohican River and Cedar Fork in Richland County, Ohio. To update and expand a portion of the Federal Emergency Management Agency detailed Flood Insurance Study, the U.S. Geological Survey (USGS) and the Muskingum Watershed Conservancy District initiated a...
Benthic foraminiferal biotic events related to the Paleocene–Eocene Thermal Maximum along the California Margin
Kristin McDougall-Reid, Cedric M John
2019, Marine Micropaleontology (150)
The faunal expression of the Paleocene-Eocene Thermal Maximum (PETM) is well documented in deep-sea sediments. However, few studies have examined continental margin sections, especially active margins. The Moreno and Lodo formations, Central California, were deposited along the eastern margin of a north-south trending forearc basin on the convergent margin of...
Quantitative evaluation of vitrinite reflectance in shale using Raman spectroscopy and multivariate analysis
Jason S. Lupoi, Paul C. Hackley, E. Birsic, Luke P. Fritz, Logan Solotky, Amy Weislogel, Steve Schlaegle
2019, Fuel (254)
The current research builds upon a previously published study that demonstrated the combination of Raman spectroscopy coupled with multivariate analysis (MVA) for the prediction of thermal maturity in coal by evaluating the efficacy of this method for the prediction of thermal maturity in shale. MVA techniques eliminate analyst bias in...
A general model of temporary aquatic habitat use: Water phenology as a life history filter
Kurt C. Heim, Jeffrey A. Falke, Thomas E. McMahon, Mark S. Wipfli, Leonardo Calle
2019, Fish and Fisheries (20) 802-816
Temporary aquatic habitats are not widely appreciated fish habitat. However, fish navigate the transient waters of intertidal zones, floodplains, intermittent and ephemeral streams, lake margins, seasonally frozen lakes and streams, and anthropogenic aquatic habitats across the globe to access important resources. The selective pressures imposed by water impermanence (i.e., freezing,...
Evaluating mechanisms of plant‐mediated effects on herbivore persistence and occupancy across an ecoregion
Jennifer L. Wilkening, Evan J. Cole, Erik A. Beever
2019, Ecosphere (10)
Contemporary climate change is rapidly creating one of the greatest challenges for management and conservation during the 21st century. Mountain ecosystems, which have a high degree of spatial heterogeneity and contain numerous habitat specialists, have been identified as particularly vulnerable. We used data from multiple years across sites spanning a...
Refinement of eDNA as an early monitoring tool at the landscape-level: Study design considerations
Erica L. Mize, Richard A. Erickson, Christopher M. Merkes, N. Berndt, K.D. Bockrath, J. Credico, N. Grueneis, J. Merry, Kyle Mosel, M.T. Tuttle-Lau, K. Von Ruden, Jon Amberg, K. Baerwaldt, S.T. Finney, E.M. Monroe
2019, Ecological Applications (29)
Natural resource managers use data on the spatial range of species to guide management decisions. These data come from survey or monitoring efforts that use a wide variety of tools. Environmental DNA (eDNA) is a surveillance tool that uses genetic markers for detecting species and holds potential as a...
Ecosystem scale loss of grazing habitat impacted by abundance of dominant herbivores
Brian D. Uher-Koch, Joel A. Schmutz, Heather M. Wilson, R Michael Anthony, Thomas L Day, Thomas F Fondell, Brian T. Person, James S. Sedinger
2019, Ecosphere (10)
Grazing lawns, patches of grazing tolerant plants with high nutrient value, provide important habitat for herbivores, and changes in abundance can impact herbivore populations. Grazing lawns are maintained in quality and quantity by repeated grazing and are a result of a positive feedback since the availability of grazing lawn...
Adaptive harvest management for the Svalbard population of pink‐footed geese: 2019 progress summary
Fred Johnson, Henning Heldbjerg, Kevin K. Clausen, Jesper Madsen
2019, Report
This report describes an Adaptive Harvest Management (AHM) program designed to maintain the Svalbard population of Pink-footed Geese (Anser brachyrhynchus) near their target level (60,000) by providing sustainable harvests in Norway and Denmark. Specifically, this report provides recent monitoring and assessment results and their implications for the 2019 hunting season. In...
Soil characteristics are associated with gradients of big sagebrush canopy structure after disturbance
David Barnard, Matthew J. Germino, Robert Arkle, John Bradford, Michael Duniway, David S. Pilliod, David Pyke, Robert Shriver, Justin L. Welty
2019, Ecosphere (10)
Reestablishing shrub canopy cover after disturbance in semi-arid ecosystems, such as sagebrush steppe, is essential to provide wildlife habitat and restore ecosystem functioning. While several studies have explored the effects of landscape and climate factors on the success or failure of sagebrush seeding, the influence of soil properties on gradients...
The roles of flow acceleration and deceleration in sediment suspension in the surf zone
Bruce E. Jaffe, SeanPaul La Selle
2019, Conference Paper, Coastal Sediments 2019, Proceedings of the 9th International Conference
Prediction of sediment suspension in the surf zone remains elusive. We explore how suspended sediment concentration at 19 cm above the bed in the mid-surf zone during a storm is influenced by flow acceleration and deceleration. There is a tendency for higher suspended sediment concentrations during onshore flow, with decelerating...
Is barotrauma an important factor in the discard mortality of Yellow Perch?
Carey Knight, Richard T. Kraus, Demetra Panos, Ann Marie Gorman, Benjamin Leonhardt, Jason Robinson, Michael J. Thomas
2019, Journal of Fish and Wildlife Management (10) 69-78
In physoclistous fishes, barotrauma caused by rapid decompression during capture may be an important source of fishing mortality that is unquantified for some fisheries. We developed a predictive logistic model for barotrauma incidence in Yellow Perch Perca flavescens and applied this model to Ohio's recreational and commercial fisheries in Lake...
Regional hydraulic geometry characteristics of stream channels in the Ouachita Mountains of Arkansas
Aaron L. Pugh, Ronald K. Redman
2019, Data Series 1104
Many stream channel infrastructure, habitat, and restoration projects are being undertaken on small streams throughout Arkansas by various Federal, State, and local agencies and by private organizations and businesses with limited data on local geomorphology and streamflow relations. Equations are needed that relate drainage area above stable stream reaches and...
3D electrical conductivity imaging of Halema‘uma‘u lava lake (Kīlauea volcano)
Lydie Gailler, James P. Kauahikaua, Jean-Francois Lenat, Andre Revil, Marceau Gresse, Abdellahi Soueid Ahmed, Nicolas Cluzel, Geeth Manthilake, Lucia Gurioli, Tim B. Johnson, Anthony Finizola, Eric Delcher
2019, Journal of Volcanology and Geothermal Research (381) 185-192
Before the 2018 collapse of the summit of Kīlauea volcano, a ca. 200 m in diameter lava lake inside of Halema‘uma‘u crater was embedded in a very active hydrothermal system. In 2015, we carried out an electrical conductivity survey and the data were inverted in 3D. The lack of conductivity contrast...
Integrating anthropogenic factors into regional-scale species distribution models — A novel application in the imperiled sagebrush biome
Juan M. Requena-Mullor, Kaitlin C. Maguire, Douglas J. Shinneman, T. Trevor Caughlin
2019, Global Change Biology (25) 3844-3858
Species distribution models (SDM) that rely on regional-scale environmental variables will play a key role in forecasting species occurrence in the face of climate change. However, in the Anthropocene, a number of local-scale anthropogenic variables, including wildfire history, land-use change, invasive species, and ecological restoration practices can override regional-scale variables...
Prevalence and diversity of avian blood parasites in a resident northern passerine
Caroline R. Van Hemert, Brandt W. Meixell, Matthew M. Smith, Colleen M. Handel
2019, Parasites & Vectors (12)
Background: Climate-related changes are expected to influence the prevalence and distribution of vector-borne haemosporidian parasites at northern latitudes, although baseline information about resident birds is still lacking. In this study, we investigated prevalence and genetic diversity of Plasmodium, Haemoproteus, and Leucocytozoon parasites infecting the Northwestern Crow (Corvus caurinus), a non-migratory...
Characterizing urban butterfly populations: The case for purposive point-count surveys
Bret J. Lang, Philip M. Dixon, Robert W. Klaver, Jan R. Thompson, Mark P. Widrlechner
2019, Urban Ecosystems (22) 1096
Developing effective butterfly monitoring strategies is key to understanding how butterflies interact with urban environments, and, in turn, to developing local conservation practices. We investigated two urban habitat types (public gardens and restored/reconstructed prairies) and compared three survey methods (Pollard transects, purposive point counts, and random point counts) to determine...
Geographic variation in the intensity of warming and phenological mismatch between Arctic shorebirds and invertebrates
Enubi Kwon, Emily L. Weiser, Richard B. Lanctot, Stephen C. Brown, H. River Gates, H. Grant Gilchrist, Steve J. Kendall, David B. Lank, Joseph R. Liebezeit, Laura McKinnon, Erica Nol, David C. Payer, Jennie Rausch, Sarah T. Saalfeld, Daniel J. Rinella, Nathan R. Senner, David Ward, Paul A. Smith, Robert C. Wissman, Brett K. Sandercock
2019, Ecological Monographs (89)
Responses to climate change can vary across functional groups and trophic levels, leading to a temporal decoupling of trophic interactions or ‘phenological mismatches.’ Despite a growing number of single-species studies that identified phenological mismatches as a nearly universal consequence of climate change, we have a limited understanding of the spatial...