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Page 382, results 9526 - 9550

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Publication Extents

Not all publications have extents, not all extents are completely accurate
A tale of two wildfires; testing detection and prediction of invasive species distributions using models fit with topographic and spectral indices
Amanda M. West, Paul H. Evangelista, Catherine S. Jarnevich, Darin Shulte
2018, Landscape Ecology (33) 969-984
ContextDeveloping species distribution models (SDMs) to detect invasive species cover and evaluate habitat suitability are high priorities for land managers.ObjectivesWe tested SDMs fit with different variable combinations to provide guidelines for future invasive species model development based on transferability between...
Soil moisture datasets at five sites in the central Sierra Nevada and northern Coast Ranges, California
Michelle A. Stern, Frank A. Anderson, Lorraine E. Flint, Alan L. Flint
2018, Data Series 1083
In situ soil moisture datasets are important inputs used to calibrate and validate watershed, regional, or statewide modeled and satellite-based soil moisture estimates. The soil moisture dataset presented in this report includes hourly time series of the following: soil temperature, volumetric water content, water potential, and total soil water content....
Stream fish colonization but not persistence varies regionally across a large North American river basin
Kit Wheeler, Seth J. Wenger, Stephen J. Walsh, Zachary P. Martin, Howard L. Jelks, Mary Freeman
2018, Biological Conservation (223) 1-10
Many species have distributions that span distinctly different physiographic regions, and effective conservation of such taxa will require a full accounting of all factors that potentially influence populations. Ecologists recognize effects of physiographic differences in topography, geology and climate on local habitat configurations, and thus the relevance of landscape heterogeneity...
Nest mortality of sagebrush songbirds due to a severe hailstorm
Jessica N. Hightower, Jason D. Carlisle, Anna D. Chalfoun
2018, Wilson Journal of Ornithology (130) 561-567
Demographic assessments of nesting birds typically focus on failures due to nest predation or brood parasitism. Extreme weather events such as hailstorms, however, can also destroy eggs and injure or kill juvenile and adult birds at the nest. We documented the effects of a severe hailstorm on 3 species of...
Evaluating spatial and temporal variability in growth and mortality for recreational fisheries with limited catch data
Yan Li, Tyler Wagner, Yan Jiao, Robert M. Lorantas, Cheryl Murphy
2018, Canadian Journal of Fisheries and Aquatic Sciences (75) 1436-1452
Understanding the spatial and temporal variability in life-history traits among populations is essential for the management of recreational fisheries. However, valuable freshwater recreational fish species often suffer from a lack of catch information. In this study, we demonstrated the use of an approach to estimate the spatial and temporal variability...
Spatial distribution of estuarine diamond-backed terrapins (Malaclemys terrapin) and risk analysis from commercial blue crab (Callinectes sapidus) trapping at the Savannah Coastal Refuges Complex, USA
Jeffrey E. Lovich, Meagan Thomas, Kirsten E. Ironside, Charles B. Yackulic, Shellie R. Puffer
2018, Ocean and Coastal Management (157) 160-167
The diamond-backed terrapin (Malaclemys terrapin) is a small estuarine turtle distributed along the Atlantic and Gulf Coasts of the USA. Terrapin populations are declining throughout their range and one of the main causes is mortality by drowning as bycatch in commercially-fished blue crab (Callinetes sapidus) traps (aka pots). We conducted...
Integrating forest inventory data and MODIS data to map species-level biomass in Chinese boreal forests
Qinglong Zhang, Hong S. He, Yu Liang, Todd Hawbaker, Paul D. Henne, Jinxun Liu, Shengli Huang, Zhiwei Wu, Chao Huang
2018, Canadian Journal of Forest Research (48) 461-479
Timely and accurate knowledge of species-level biomass is essential for forest managers to sustain forest resources and respond to various forest disturbance regimes. In this study, maps of species-level biomass in Chinese boreal forests were generated by integrating Moderate Resolution Imaging Spectroradiometer (MODIS) images with forest inventory data using k nearest neighbor...
Process convolution approaches for modeling interacting trajectories
Henry R. Scharf, Mevin Hooten, Devin S. Johnson, John W. Durban
2018, Environmetrics (29)
Gaussian processes are a fundamental statistical tool used in a wide range of applications. In the spatiotemporal setting, several families of covariance functions exist to accommodate a wide variety of dependence structures arising in different applications. These parametric families can be restrictive and are insufficient in some situations. In contrast,...
Numerical model of geochronological tracers for deposition and reworking applied to the Mississippi subaqueous delta
Justin J. Birchler, Courtney K. Harris, Tara A. Kniskern, Christopher R. Sherwood
2018, Journal of Coastal Research (Special Issue 85) 456-460
Measurements of naturally occurring, short-lived radioisotopes from sediment cores on the Mississippi subaqueous delta have been used to infer event bed characteristics such as depositional thicknesses and accumulation rates. Specifically, the presence of Beryllium-7 (7Be) indicates recent riverine-derived terrestrial sediment deposition; while Thorium-234 (234Th) provides evidence of recent suspension in...
Operational nowcasting of electron flux levels in the outer zone of Earth's radiation belt
Tim Coleman, James P. McCollough, Shawn L. Young, E. Joshua Rigler
2018, Space Weather (16) 501-518
We describe a lightweight, accurate nowcasting model for electron flux levels measured by the Van Allen probes. Largely motivated by Rigler et al. (2004, https://doi.org/10.1029/2003SW000036), we turn to a time‐varying linear filter of previous flux levels and Kp. We train and test this model on data gathered from the 2.10 MeV channel...
Estimating fluvial discharges coincident with 21st century coastal storms modeled with CoSMoS
Li H. Erikson, Andrea C. O'Neill, Patrick L. Barnard
2018, Journal of Coastal Research (Special Issue No. 85) 791-795
On the open coast, flooding is largely driven by tides, storm surge, waves, and in areas near coastal inlets, the magnitude and co-occurrence of high fluvial discharges. Statistical methods are typically used to estimate the individual probability of coastal storm and fluvial discharge occurrences for use in sophisticated flood hazard...
Atmospheric and surface climate associated with 1986–2013 wildfires in North America
Steven W. Hostetler, Patrick J. Bartlein, Jay R. Alder
2018, Journal of Geophysical Research: Biogeosciences (123) 1588-1609
We analyze climate simulations conducted with the RegCM3 regional climate model on 50‐ and 15‐km model grids to diagnose the dependence of wildfire incidence and area burned variations on monthly climate long‐term means and anomalies over North America for the period 1986–2013. We created a new wildfire database by merging...
Interaction between hydraulic fracture and a preexisting fracture under triaxial stress conditions
Saied Mighani, David A. Lockner, Brian D. Kilgore, Farrokh Sheibani, Brian Evans
2018, Conference Paper, SPE Hydraulic Fracturing Technology Conference and Exhibition
Enhanced reservoir connectivity generally requires maximizing the intersection between hydraulic fracture (HF) and preexisting underground natural fractures (NF), while having the hydraulic fracture cross the natural fractures (and not arrest). We have studied the interaction between a hydraulic fracture and a polished saw-cut fault. The experiments include a hydraulic fracture...
The influence of sea level rise on the regional interdependence of coastal infrastructure
Ruo-Quian Wang, Mark T. Stacey, Liv M. Herdman, Patrick L. Barnard, Li H. Erikson
2018, Earth's Future (6) 677-688
Sea level rise (SLR) is placing both immediate and long‐term pressures on coastal communities to take protective actions. Projects in the United States, and in many locations throughout the world, generally involve local jurisdictions raising the elevation of shoreline protection elements, with limited or no analysis of the feedback between...
Effects of water-level management and hatchery supplementation on kokanee recruitment in Lake Pend Oreille, Idaho
Steven L. Whitlock, Michael C. Quist, Andrew M. Dux
2018, Article
Resource managers have been attempting to recover the kokanee (Oncorhynchus nerka) population in Lake Pend Oreille, Idaho for more than three decades using an annual stocking program and an experimental water-level management strategy. This study evaluated the effect of both management actions on kokanee recruitment. A bootstrap-based generalized Ricker model...
Warming is driving decreases in snow fractions while runoff efficiency remains mostly unchanged in snow-covered areas of the western United States
Gregory J. McCabe, David M. Wolock, Melissa Valentin
2018, Journal of Hydrometeorology (19) 803-814
Winter snowfall and accumulation is an important component of the surface water supply in the western United States. In these areas, increasing winter temperatures T associated with global warming can influence the amount of winter precipitation P that falls as snow S. In this study we examine long-term trends in the fraction of winter P that falls...
Research, monitoring, and evaluation of emerging issues and measures to recover the Snake River fall Chinook salmon ESU
Kenneth Tiffan, John M. Plumb, Russell W. Perry, John Erhardt, Rulon J. Hemingway, Brad Bickford, Tobyn N. Rhodes, William P. Connor, Frank L. Mullins
2018, Report
The portion of the Snake River fall Chinook Salmon Oncorhynchus tshawytscha ESU that spawns upstream of Lower Granite Dam transitioned from low to high abundance during 1992–2017 in association with U.S. Endangered Species Act recovery efforts and other federally mandated actions. This annual report focuses on (1) numeric and habitat...
Quantifying temporal trends in fisheries abundance using Bayesian dynamic linear models: A case study of riverine Smallmouth Bass populations
Megan K. Schall, Vicki S. Blazer, Robert M. Lorantas, Geoffrey Smith, John E. Mullican, Brandon J. Keplinger, Tyler Wagner
2018, North American Journal of Fisheries Management (38) 493-501
Detecting temporal changes in fish abundance is an essential component of fisheries management. Because of the need to understand short‐term and nonlinear changes in fish abundance, traditional linear models may not provide adequate information for management decisions. This study highlights the utility of Bayesian dynamic linear models (DLMs) as a...
Response of moose to a high‐density road network
David W. Wattles, Katherine A. Zeller, Stephen DeStefano
2018, Journal of Wildlife Management (82) 929-939
Road networks and the disturbance associated with vehicle traffic alter animal behavior, movements, and habitat selection. The response of moose (Alces americanus) to roads has been documented in relatively rural areas, but less is known about moose response to roads in more highly roaded landscapes. We examined road‐crossing frequencies and...
Rivers are social–ecological systems: Time to integrate human dimensions into riverscape ecology and management
Jason B. Dunham, Paul L. Angermeier, Shelley D. Crausbay, Amanda E. Cravens, Hannah Gosnell, Jamie McEvoy, Max A. Moritz, Nejem Raheem, Todd Sanford
2018, WIREs Water (5) 1-10
Incorporation of concepts from landscape ecology into understanding and managing riverine ecosystems has become widely known as riverscape ecology. Riverscape ecology emphasizes interactions among processes at different scales and their consequences for valued ecosystem components, such as riverine fishes. Past studies have focused strongly on understanding the ecological processes in...
Demographic response of Louisiana Waterthrush, a stream obligate songbird of conservation concern, to shale gas development
Mack W. Frantz, Petra B. Wood, James Sheehan, Gregory George
2018, Condor (120) 265-282
Shale gas development continues to outpace the implementation of best management practices for wildlife affected by development. We examined demographic responses of the Louisiana Waterthrush (Parkesia motacilla) to shale gas development during 2009–2011 and 2013–2015 in a predominantly forested landscape in West Virginia, USA. Forest cover across the study area...
Co‐occurrence dynamics of endangered Lower Keys marsh rabbits and free‐ranging domestic cats: Prey responses to an exotic predator removal program
Michael V. Cove, Beth Gardner, Theodore R. Simons, Allan F. O’Connell
2018, Ecology and Evolution (8) 4042-4052
The Lower Keys marsh rabbit (Sylvilagus palustris hefneri) is one of many endangered endemic species of the Florida Keys. The main threats are habitat loss and fragmentation from sea‐level rise, development, and habitat succession. Exotic predators such as free‐ranging domestic cats (Felis catus) pose an additional threat to these endangered...
Density of American black bears in New Mexico
Matthew J. Gould, James W. Cain III, Gary W. Roemer, William R. Gould, Stewart Liley
2018, Journal of Wildlife Management (82) 775-788
Considering advances in noninvasive genetic sampling and spatially explicit capture–recapture (SECR) models, the New Mexico Department of Game and Fish sought to update their density estimates for American black bear (Ursus americanus) populations in New Mexico, USA, to aide in setting sustainable harvest limits. We estimated black bear density in...
Reduced arctic tundra productivity linked with landform and climate change interactions
Mark J. Lara, Ingmar Nitze, Guido Grosse, Philip Martin, A. David McGuire
2018, Scientific Reports (8)
Arctic tundra ecosystems have experienced unprecedented change associated with climate warming over recent decades. Across the Pan-Arctic, vegetation productivity and surface greenness have trended positively over the period of satellite observation. However, since 2011 these trends have slowed considerably, showing signs of browning in many regions. It is unclear what...
The non-linear, interactive effects of population density and climate drive the geographical patterns of waterfowl survival
Qing Zhao, G. Scott Boomer, William L. Kendall
2018, Biological Conservation (221) 1-9
On-going climate change has major impacts on ecological processes and patterns. Understanding the impacts of climate on the geographical patterns of survival can provide insights to how population dynamics respond to climate change and provide important information for the development of appropriate conservation strategies at regional scales. It is challenging to...