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Publications

Filter Total Items: 1990

The influence of stream channels on distributions of Larrea tridentata and Ambrosia dumosa in the Mojave Desert, CA, USA: Patterns, mechanisms and effects of stream redistribution

Drainage channels are among the most conspicuous surficial features of deserts, but little quantitative analysis of their influence on plant distributions is available. We analysed the effects of desert stream channels (‘washes’) on Larrea tridentata and Ambrosia dumosa density and cover on an alluvial piedmont in the Mojave Desert, based on a spatial analysis of transect data encompassing a total
Authors
S. Schwinning, D.R. Sandquist, D. M. Miller, D. R. Bedford, S. L. Phillips, J. Belnap

Effects of nitrogen deposition and empirical nitrogen critical loads for ecoregions of the United States

Human activity in the last century has led to a significant increase in nitrogen (N) emissions and atmospheric deposition. This N deposition has reached a level that has caused or is likely to cause alterations to the structure and function of many ecosystems across the United States. One approach for quantifying the deposition of pollution that would be harmful to ecosystems is the determination
Authors
L.H. Pardo, M.E. Fenn, C.L. Goodale, L.H. Geiser, C. T. Driscoll, E.B. Allen, Jill Baron, R. Bobbink, W.D. Bowman, C.M. Clark, B. Emmett, F.S. Gilliam, T.L. Greaver, S.J. Hall, E.A. Lilleskov, L. Liu, J.A. Lynch, K.J. Nadelhoffer, S.S. Perakis, M. J. Robin-Abbott, J.L. Stoddard, K.C. Weathers, R.L. Dennis

Decomposition of heterogeneous organic matter and its long-term stabilization in soils

Soil organic matter is a complex mixture of material with heterogeneous biological, physical, and chemical properties. Decomposition models represent this heterogeneity either as a set of discrete pools with different residence times or as a continuum of qualities. It is unclear though, whether these two different approaches yield comparable predictions of organic matter dynamics. Here, we compare
Authors
C.A. Sierra, M. E. Harmon, Steven Perakis

Seasonal movements and environmental triggers to fall migration of Sage Sparrows

Post-breeding ecology of shrubland passerines prior to onset of migration is unknown relative to dynamics of breeding areas. We radiomarked and monitored 38 Sage Sparrows (Amphispiza belli ssp. nevadensis) at one site in Oregon and two in Nevada from September to mid-November 2007 to track local movements, estimate seasonal range sizes, and characterize weather patterns triggering onset of migrati
Authors
K.A. Fesenmyer, S.T. Knick

Preening behavior of adult gyrfalcons tagged with backpack transmitters

Radio transmitters provide data that enhance understanding of raptor biology (Walls and Kenward 2007) and are now used to answer a multitude of research questions (Meyburg and Fuller 2007). However, transmitters affect the birds that carry them (Barron et al. 2010), and it is important to document and evaluate such effects (Casper 2009). For example, decreased survival has been documented in Prair
Authors
T.L. Booms, P.F. Schempf, M.R. Fuller

Non-native species impacts on pond occupancy by an anuran

Non-native fish and bullfrogs (Lithobates catesbeianus) are frequently cited as contributing to the decline of ranid frogs in the western United States, so we hypothesized that non-native species, habitat, or a combination of these relate to the probability of local extinction for northern red-legged frogs (Rana aurora) in Oregon, USA. We also hypothesized that the probability of colonization rela
Authors
Michael J. Adams, Christopher Pearl, Stephanie Galvan, Brome McCreary

Factors associated with extirpation of sage-grouse

Geographic ranges of Greater Sage-Grouse (Centrocercus urophasianus) and Gunnison Sage-Grouse (C. minimus) have contracted across large areas in response to habitat loss and detrimental land uses. However, quantitative analyses of the environmental factors most closely associated with range contraction have been lacking, results of which could be highly relevant to conservation planning. Consequen
Authors
Michael J. Wisdom, Cara W. Meinke, Steven T. Knick, Michael A. Schroeder

Chapter 3: Changes to the Wyoming Basins landscape from oil and natural gas development

Oil and natural gas have been produced in Wyoming since the late 1800s although the rate of extraction has increased substantially in the last two decades. Well pads, roads, and infrastructure built to support resource development alter native vegetation configuration; however, the rate and effect of land cover change resulting from oil and gas extraction has not been quantified across the region.
Authors
Sean P. Finn, Steven T. Knick

Great Basin Integrated Landscape Monitoring Pilot Summary Report

The Great Basin Integrated Landscape Monitoring Pilot project (GBILM) was one of four regional pilots to implement the U.S. Geological Survey (USGS) Science Thrust on Integrated Landscape Monitoring (ILM) whose goal was to observe, understand, and predict landscape change and its implications on natural resources at multiple spatial and temporal scales and address priority natural resource managem
Authors
Sean P. Finn, Kate Kitchell, Lori Anne Baer, David R. Bedford, Matthew L. Brooks, Alan L. Flint, Lorraine E. Flint, J.R. Matchett, Amy Mathie, David M. Miller, David S. Pilliod, Alicia Torregrosa, Andrea Woodward

Framework for ecological monitoring on lands of Alaska National Wildlife Refuges and their partners

National Wildlife Refuges in Alaska and throughout the U.S. have begun developing a spatially comprehensive monitoring program to inform management decisions, and to provide data to broader research projects. In an era of unprecedented rates of climate change, monitoring is essential to detecting, understanding, communicating and mitigating climate-change effects on refuge and other resources unde
Authors
Andrea Woodward, Erik A. Beever

Dr. Carl Marti 1944-2010

No abstract available.
Authors
Michael N. Kochert, Karen Steenhof, Patricia L. Kennedy

Analysis of California Condor (Gymnogyps californianus) use of six management units using location data from global positioning system transmitters, southern California, 2004-09-Initial report

This report provides an analysis of California Condor (Gymnogyps californianus) space use of six management units in southern California (Hopper Mountain and Bitter Creek National Wildlife Refuges, Wildlands Conservancy-Wind Wolves Preserve, Tejon Mountain Village Specific Plan, California Condor Study Area, and the Tejon Ranch excluding Tejon Mountain Village Specific Plan and California Condor S
Authors
Matthew Johnson, Jeffrey Kern, Susan M. Haig