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Page 9, results 201 - 225

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Not all publications have extents, not all extents are completely accurate
Elevated Rocky Mountain elk numbers prevent positive effects of fire on quaking aspen (Populus tremuloides) recruitment
David Solance Smith, Stephen M. Fettig, Matthew A. Bowker
2016, Forest Ecology and Management (362) 46-54
Quaking aspen (Populus tremuloides) is the most widespread tree species in North America and has supported a unique ecosystem for tens of thousands of years, yet is currently threatened by dramatic loss and possible local extinctions. While multiple factors such as climate change and fire suppression are thought to contribute...
Integrative modelling reveals mechanisms linking productivity and plant species richness
James B. Grace, T. Michael Anderson, Eric W. Seabloom, Elizabeth T. Borer, Peter B. Adler, W Stanley Harpole, Yann Hautier, Helmut Hillebrand, Eric M. Lind, Meelis Partel, Jonathan D. Bakker, Yvonne M. Buckley, Michael J. Crawley, Ellen Ingman Damschen, Kendi F. Davies, Philip A. Fay, Jennifer Firn, Daniel S. Gruner, Andy Hector, Johannes M.H. Knops, Andrew S. MacDougall, Brett A. Melbourne, John W. Morgan, John L. Orrock, Suzanne M. Prober, Melinda D. Smith
2016, Nature (529) 390-393
How ecosystem productivity and species richness are interrelated is one of the most debated subjects in the history of ecology. Decades of intensive study have yet to discern the actual mechanisms behind observed global patterns. Here, by integrating the predictions from multiple theories into a single model and using data...
Evaluation of the hydraulic and biological performance of the portable floating fish collector at Cougar Reservoir and Dam, Oregon, 2014
John W. Beeman, Scott D. Evans, Philip V. Haner, Hal C. Hansel, Amy C. Hansen, Gabriel S. Hansen, Tyson W. Hatton, Jamie M. Sprando, Collin D. Smith, Noah S. Adams
2016, Open-File Report 2016-1003
The biological and hydraulic performance of a new portable floating fish collector (PFFC) located in a cul-de-sac within the forebay of Cougar Dam, Oregon, was evaluated during 2014. The purpose of the PFFC was to explore surface collection as a means to capture juvenile salmonids at one or more sites...
Age, growth and fall diet of channel catfish in Cheat Lake, West Virginia
Corbin D. Hilling, Stuart A. Welsh, Dustin M. Smith
2016, Journal of Fish and Wildlife Management (7) 304-314
Acidification has historically impaired Cheat Lake's fish community, but recent mitigation efforts within the Cheat River watershed have improved water quality and species richness. Presently, channel catfish Ictalurus punctatus are abundant and attain desirable sizes for anglers. We evaluated the age, growth, and fall diet of the population. We collected...
Regional tectonic setting for the Trinidad earthquake swarms (2000-2012) from gravity and magnetic data
Carol A. Finn, Mason A. Kass, Bruce D. Smith
2015, Conference Paper, Symposium on the Application of Geophysics to Engineering and Environmental Problems
Earthquakes in the Raton basin near Trinidad, Colorado, (Figure 1) are located (Rubenstein et. al., 2014) near a major gravity and magnetic boundary. These earthquakes also occur in an area of hydrocarbon production that includes several high-capacity produced water injection wells. This presentation gives a very basic outline of the...
Detection probabilities of electrofishing, hoop nets, and benthic trawls for fishes in two western North American rivers
Christopher D. Smith, Michael C. Quist, Ryan S. Hardy
2015, Journal of Fish and Wildlife Management (6) 371-391
Research comparing different sampling techniques helps improve the efficiency and efficacy of sampling efforts. We compared the effectiveness of three sampling techniques (small-mesh hoop nets, benthic trawls, boat-mounted electrofishing) for 30 species in the Green (WY, USA) and Kootenai (ID, USA) rivers by estimating conditional detection probabilities (probability of detecting...
Environmental DNA calibration study interim technical review report December 2014
Kelly Baerwaldt, Meredith L. Bartron, Kurt Schilling, Debbie Lee, Edmond Russo, Trudy Estes, Richard Fischer, Beth Fleming, Michael P. Guilfoyle, Jack Killgore, Richard Lance, Edward Perkins, Martin Schultz, David Smith, Jon J. Amberg, Duane Chapman, Mark P. Gaikowski, Katy E. Klymus, Catherine A. Richter
2015, Report
The Environmental DNA Calibration Study (ECALS) is a multi-year study to improve the understanding and interpretation of the detection of Asian carp DNA in environmental samples (eDNA) used in early detection monitoring. eDNA surveillance programs seek to detect the presence of genetic material (DNA in cells sloughed off in slime,...
Developing a conservation strategy to maximize persistence of an endangered freshwater mussel species while considering management effectiveness and cost
David R. Smith, Sarah E. McRae, Tom Augspurger, Judith A. Ratcliffe, Robert B. Nichols, Chris B. Eads, Tim Savidge, Arthur E. Bogan
2015, Freshwater Science (34) 1324-1339
We used a structured decision-making process to develop conservation strategies to increase persistence of Dwarf Wedgemussel (Alasmidonta heterodon) in North Carolina, USA, while accounting for uncertainty in management effectiveness and considering costs. Alternative conservation strategies were portfolios of management actions that differed by location of management actions on the landscape....
Assessment and Mmanagement of North American horseshoe crab populations, with emphasis on a multispecies framework for Delaware Bay, U.S.A. populations: Chapter 24
Michael J. Millard, John A. Sweka, Conor P. McGowan, David R. Smith
2015, Book chapter, Changing Global Perspectives on Horseshoe Crab Biology, Conservation and Management
The horseshoe crab fishery on the US Atlantic coast represents a compelling fishery management story for many reasons, including ecological complexity, health and human safety ramifications, and socio-economic conflicts. Knowledge of stock status and assessment and monitoring capabilities for the species have increased greatly in the last 15 years and...
Horseshoe crab spawning activity in Delaware Bay, USA, after harvest reduction: A mixed-model analysis
David R. Smith, Timothy J. Robinson
2015, Estuaries and Coasts (38) 2345-2354
A Delaware Bay, USA, standardized survey of spawning horseshoe crabs, Limulus polyphemus, was carried out in 1999 − 2013 through a citizen science network. Previous trend analyses of the data were at the state (DE or NJ) or bay-wide levels. Here, an alternative mixed-model regression analysis was used to estimate...
USGS Arctic Science Strategy
Mark Shasby, Durelle Smith
2015, Fact Sheet 2015-3049
The United States is one of eight Arctic nations responsible for the stewardship of a polar region undergoing dramatic environmental, social, and economic changes. Although warming and cooling cycles have occurred over millennia in the Arctic region, the current warming trend is unlike anything recorded previously and is affecting the...
Social living mitigates the costs of a chronic illness in a cooperative carnivore
Emily S. Almberg, Paul C. Cross, Andrew P. Dobson, Douglas W. Smith, Matthew C Metz, Daniel R. Stahler, Peter J. Hudson
2015, Ecology Letters (18) 660-667
Infection risk is assumed to increase with social group size, and thus be a cost of group living. We assess infection risk and costs with respect to group size using data from an epidemic of sarcoptic mange (Sarcoptes scabiei) among grey wolves (Canis lupus). We demonstrate that group size does...
The distribution of selected elements and minerals in soil of the conterminous United States
Laurel G. Woodruff, William F. Cannon, David B. Smith, Federico Solano
2015, Journal of Geochemical Exploration (154) 49-60
In 2007, the U.S. Geological Survey initiated a low-density (1 site per 1600 km2, 4857 sites) geochemical and mineralogical survey of soil of the conterminous United States as part of the North American Soil Geochemical Landscapes Project. Three soil samples were collected, if possible, from each site; (1) a sample from...
Group composition effects on aggressive interpack interactions of gray wolves in Yellowstone National Park
Kira A. Cassidy, Daniel R. MacNulty, Daniel R. Stahler, Douglas W. Smith, L. David Mech
2015, Behavioral Ecology (26) 1352-1360
Knowledge of characteristics that promote group success during intraspecific encounters is key to understanding the adaptive advantages of sociality for many group-living species. In addition, some individuals in a group may be more likely than others to influence intergroup conflicts, a relatively neglected idea in research on social animals. Here...
Developing objectives with multiple stakeholders: adaptive management of horseshoe crabs and Red Knots in the Delaware Bay
Conor P. McGowan, James E. Lyons, David Smith
2015, Environmental Management (55) 972-982
Structured decision making (SDM) is an increasingly utilized approach and set of tools for addressing complex decisions in environmental management. SDM is a value-focused thinking approach that places paramount importance on first establishing clear management objectives that reflect core values of stakeholders. To be useful for management, objectives must be...
Airborne electromagnetic and magnetic survey data of the Paradox and San Luis Valleys, Colorado
Lyndsay B. Ball, Benjamin R. Bloss, Paul A. Bedrosian, V. J. S. Grauch, Bruce D. Smith
2015, Open-File Report 2015-1024
In October 2011, the U.S. Geological Survey (USGS) contracted airborne magnetic and electromagnetic surveys of the Paradox and San Luis Valleys in southern Colorado, United States. These airborne geophysical surveys provide high-resolution and spatially comprehensive datasets characterizing the resistivity structure of the shallow subsurface of each survey region, accompanied by...
Mars Reconnaissance Orbiter and Opportunity observations of the Burns formation: crater hopping at Meridiani Planum
R.E. Arvidson, J.F. Bell III, J.G. Catalano, B.C. Clark, V.K. Fox, Ralf Gellert, J.P. Grotzinger, E.A. Guinness, Kenneth E. Herkenhoff, A.H. Knoll, M.G.A. Lapotre, S. M. McLennan, D. W. Ming, R.V. Morris, S.L. Murchie, K. E. Powell, M. D. Smith, S. W. Squyres, M.J. Wolff, J.J. Wray
2015, Journal of Geophysical Research E: Planets (120) 429-451
Compact Reconnaissance Imaging Spectrometer for Mars hyperspectral (1.0–2.65 µm) along-track oversampled observations covering Victoria, Santa Maria, Endeavour, and Ada craters were processed to 6 m/pixel and used in combination with Opportunity observations to detect and map hydrated Mg and Ca sulfate minerals in the Burns formation. The strongest spectral absorption features were...
Reducing nitrogen export from the corn belt to the Gulf of Mexico: agricultural strategies for remediating hypoxia
Eileen McLellan, Dale M. Robertson, Keith Schilling, Mark Tomer, Jill Kostel, Douglas G. Smith, Kevin King
2015, Journal of the American Water Resources Association (51) 263-289
SPAtially Referenced Regression on Watershed models developed for the Upper Midwest were used to help evaluate the nitrogen-load reductions likely to be achieved by a variety of agricultural conservation practices in the Upper Mississippi-Ohio River Basin (UMORB) and to compare these reductions to the 45% nitrogen-load reduction proposed to remediate...
Climatic controls of aboveground net primary production in semi-arid grasslands along a latitudinal gradient portend low sensitivity to warming
Whitney Mowll, Dana M. Blumenthal, Karie Cherwin, Anine Smith, Amy J. Symstad, Lance Vermeire, Scott L. Collins, Melinda D. Smith, Alan K. Knapp
2015, Oecologia (177) 959-969
Although climate models forecast warmer temperatures with a high degree of certainty, precipitation is the primary driver of aboveground net primary production (ANPP) in most grasslands. Conversely, variations in temperature seldom are related to patterns of ANPP. Thus forecasting responses to warming is a challenge, and raises the question: how...
Wolves on the hunt: The behavior of wolves hunting wild prey
L. David Mech, Douglas W. Smith, Daniel R. MacNulty
2015, Book
The interactions between apex predators and their prey are some of the most awesome and meaningful in nature—displays of strength, endurance, and a deep coevolutionary history. And there is perhaps no apex predator more impressive and important in its hunting—or more infamous, more misjudged—than the wolf. Because of wolves’ habitat,...
Implementation of a framework for multi-species, multi-objective adaptive management in Delaware Bay
Conor P. McGowan, David R. Smith, James D. Nichols, James E. Lyons, John A. Sweka, Kevin Kalasz, Lawrence J. Niles, Richard Wong, Jeffrey Brust, Michelle C. Davis, Braddock Spear
2015, Biological Conservation (191) 759-769
Decision analytic approaches have been widely recommended as well suited to solving disputed and ecologically complex natural resource management problems with multiple objectives and high uncertainty. However, the difference between theory and practice is substantial, as there are very few actual resource management programs that represent formal applications of decision...
Ocean minerals
James R. Hein, Kira L. Mizell
Hance D. Smith, Juan Luis Suarez de Vivero, Tundi S. Agardy, editor(s)
2015, Book chapter, Routledge handbook of ocean resources and management
Nearly 71 percent of the Earth is covered by ocean, yet during the entire history of societies, the mineral resources essential for nation building have been acquired solely from the continents. Deep-ocean minerals were discovered over a century ago during the Challenger...
Impacts of fire management on aboveground tree carbon stocks in Yosemite and Sequoia & Kings Canyon National Parks
John R. Matchett, James A. Lutz, Leland W. Tarnay, Douglas G. Smith, Kendall M.L. Becker, Matthew L. Brooks
2015, Report, Natural Resource Report NPS/SIEN/NRR—2015/910
Forest biomass on Sierra Nevada landscapes constitutes one of the largest carbon stocks in California, and its stability is tightly linked to the factors driving fire regimes. Research suggests that fire suppression, logging, climate change, and present management practices in Sierra Nevada forests have altered historic patterns of landscape carbon...
Threshold-dependent sample sizes for selenium assessment with stream fish tissue
Nathaniel P. Hitt, David R. Smith
2015, Integrated Environmental Assessment and Management (11) 143-149
Natural resource managers are developing assessments of selenium (Se) contamination in freshwater ecosystems based on fish tissue concentrations. We evaluated the effects of sample size (i.e., number of fish per site) on the probability of correctly detecting mean whole-body Se values above a range of potential management thresholds. We modeled...
Environmental DNA calibration study. Interim technical review report
K. Baerwaldt, Meredith L. Bartron, K. Schilling, Debbie Lee, Edmond Russo, Trudy Estes, Richard Fischer, Beth Fleming, Michael P. Guilfoyle, K. Jack Kilgore, Richard Lance, Edward Perkins, Martin Schultz, David Smith, Jon J. Amberg, Duane Chapman, Mark P. Gaikowski, Katy E. Klymus, Cathy A. Richter
2014, Report
Invasive aquatic nuisance species pose a major threat to aquatic ecosystems worldwide. Invasive Asian carps, including bighead carp (Hypophthalmichthys nobilis) and silver carp (H. molitrix) have been steadily dispersing upstream through the Mississippi, Illinois, and Des Plaines Rivers since the 1990s. To prevent further movement up the Illinois River into...