Publications
Below are publications associated with the Southwest Biological Science Center's research.
If you are unable to access or download a product after you've clicked through the links below, email mhartwell@usgs.gov with your request. Please include the citation in your email and/or a link to the product. Note that each product has several link options once you click on the title.
Filter Total Items: 1332
Using large-scale flow experiments to rehabilitate Colorado River ecosystem function in Grand Canyon: Basis for an adaptive climate-resilient strategy
Adaptive management of Glen Canyon Dam is improving downstream resources of the Colorado River in Glen Canyon National Recreation Area and Grand Canyon National Park. The Glen Canyon Dam Adaptive Management Program (AMP), a federal advisory committee of 25 members with diverse special interests tasked to advise the U.S. Department of the Interior), was established in 1997 in response to the 1992 G
Authors
Theodore S. Melis, William E. Pine, Josh Korman, Michael D. Yard, Shaleen Jain, Roger S. Pulwarty
Spatial and ecological variation in dryland ecohydrological responses to climate change: implications for management
Ecohydrological responses to climate change will exhibit spatial variability and understanding the spatial pattern of ecological impacts is critical from a land management perspective. To quantify climate change impacts on spatial patterns of ecohydrology across shrub steppe ecosystems in North America, we asked the following question: How will climate change impacts on ecohydrology differ in magn
Authors
Kyle A. Palmquist, Daniel R. Schlaepfer, John B. Bradford, William K. Lauenroth
Bed texture mapping in large rivers using recreational-grade sidescan sonar
The size-distribution and spatial organization of bed sediment, or bed ‘texture’, is a fundamental attribute of natural channels and is one important component of the physical habitat of aquatic ecosystems. ‘Recreational-grade’ sidescan sonar systems now offer the possibility of imaging, and subsequently quantifying bed texture at high resolution with minimal cost, or logistical effort. We are inv
Authors
Daniel Hamill, Joseph M. Wheaton, Daniel D. Buscombe, Paul E. Grams, Theodore S. Melis
Climate drives shifts in grass reproductive phenology across the western USA
The capacity of grass species to alter their reproductive timing across space and through time can indicate their ability to cope with environmental variability and help predict their future performance under climate change.We determined the long-term (1895–2013) relationship between flowering times of grass species and climate in space and time using herbarium records across ecoregions of the wes
Authors
Seth M. Munson, A. Lexine Long
Cryptic invasion of Northern Leopard Frogs (Rana pipiens) across phylogeographic boundaries and a dilemma for conservation of a declining amphibian
Anthropogenic introduction of species is a major contributor to loss of biodiversity. Translocations within the range of a species are less frequently recognized, but have the potential for negative effects as well. Genetic mixing may lead to loss of local adaptations or further decline through outbreeding depression. These cryptic invasions may be quite difficult to recognize, but genetic tools c
Authors
Ryan P. O'Donnell, Charles A. Drost, Karen E. Mock
Effects of climate and water balance across grasslands of varying C3 and C4 grass cover
Climate change in grassland ecosystems may lead to divergent shifts in the abundance and distribution of C3 and C4 grasses. Many studies relate mean climate conditions over relatively long time periods to plant cover, but there is still much uncertainty about how the balance of C3and C4 species will be affected by climate at a finer temporal scale than season (individual events to months). We moni
Authors
Dana L. Witwicki, Seth M. Munson, David P. Thoma
Competitive exclusion over broad spatial extents is a slow process: Evidence and implications for species distribution modeling
There is considerable debate about the role of competition in shaping species distributions over broad spatial extents. This debate has practical implications because predicting changes in species' geographic ranges in response to ongoing environmental change would be simpler if competition could be ignored. While this debate has been the subject of many reviews, recent literature has not addresse
Authors
Charles B. Yackulic
The automated reference toolset: A soil-geomorphic ecological potential matching algorithm
Ecological inventory and monitoring data need referential context for interpretation. Identification of appropriate reference areas of similar ecological potential for site comparison is demonstrated using a newly developed automated reference toolset (ART). Foundational to identification of reference areas was a soil map of particle size in the control section (PSCS), a theme in US Soil Taxonomy.
Authors
Travis W. Nauman, Michael C. Duniway
Sagebrush, greater sage-grouse, and the occurrence and importance of forbs
Big sagebrush (Artemisia tridentata Nutt.) ecosystems provide habitat for sagebrush-obligate wildlife species such as the Greater Sage-Grouse (Centrocercus urophasianus). The understory of big sagebrush plant communities is composed of grasses and forbs that are important sources of cover and food for wildlife. The grass component is well described in the literature, but the composition, abundance
Authors
Victoria E. Pennington, Daniel R. Schlaepfer, Jeffrey L. Beck, John B. Bradford, Kyle A. Palmquist, William K. Lauenroth
Phenology of the adult angel lichen moth (Cisthene angelus) in Grand Canyon, USA
We investigated the phenology of adult angel lichen moths (Cisthene angelus) along a 364-km long segment of the Colorado River in Grand Canyon, Arizona, USA, using a unique data set of 2,437 light-trap samples collected by citizen scientists. We found that adults of C. angelus were bivoltine from 2012 to 2014. We quantified plasticity in wing lengths and sex ratios among the two generations and ac
Authors
Anya N. Metcalfe, Theodore A. Kennedy, Jeffrey D. Muehlbauer
Long-term continuous acoustical suspended-sediment measurements in rivers – Theory, evaluation, and results from 14 stations on five rivers
We have developed a physically based method for using two acoustic frequencies to measure suspended-silt-and-clay concentration, suspended-sand concentration, and suspended-sand median grain size in river cross sections at 15-minute intervals over decadal timescales. The method is strongly grounded in the extensive scientific literature on the scattering of sound by suspensions of small particles
Authors
David Topping, Scott A. Wright, Ronald E. Griffiths, David Dean
Building sandbars in Grand Canyon
Now, by implementing a new strategy that calls for repeated releases of large volumes of water from the dam, the U.S. Department of the Interior seeks to increase the size and number of these sandbars. Three years into the “High Flow Experiment” protocol, the releases appear to be achieving the desired effect. Many sandbars have increased in size following each controlled flood and the cumulative