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Survival of the endangered Pima pineapple cactus: Does clearing before prescribed fire alter survival postfire?
Federal land managers and ranchers often use prescribed fire as a tool to reduce invading woody plants within desert grasslands of the arid southwestern United States. Managers must evaluate the threat of the burn toward the health and survival of plants of concern including how preemptive clearing before prescribed fire might benefit these...
Thomas, Kathryn A.; Jarchow, Christopher; Crawford, Julie A. The planetary data system
In the early 1980s, the Space Science Board (SSB) of the National Research Council was concerned about the poor and inconsistent treatment of scientific information returned from NASA’s space science missions. The SSB formed a panel [The Committee on Data Management and Computation (CODMAC)] to assess the situation and make recommendations to NASA...
Acton, Charles; Slavney, Susan; Arvidson, Raymond E.; Gaddis, Lisa R.; Gordon, Mitchell; Lavoie, Susan Effects of environmental covariates and density on the catchability of fish populations and interpretation of catch per unit effort trends
Article for outlet: Fisheries Research. Abstract: Quantifying temporal and spatial trends in abundance or relative abundance is required to evaluate effects of harvest and changes in habitat for exploited and endangered fish populations. In many cases, the proportion of the population or stock that is captured (catchability or capture probability...
Korman, Josh; Yard, Mike
Modern landscape processes affecting archaeological sites along the Colorado River corridor downstream of Glen Canyon Dam, Glen Canyon National Recreation Area, Arizona
The landscape of the Colorado River through Glen Canyon National Recreation Area formed over many thousands of years and was modified substantially after the completion of Glen Canyon Dam in 1963. Changes to river flow, sediment supply, channel base level, lateral extent of sedimentary terraces, and vegetation in the post-dam era have modified the...
East, Amy E.; Sankey, Joel B.; Fairley, Helen C.; Caster, Joshua J.; Kasprak, Alan Enhancing wind erosion monitoring and assessment for U.S. rangelands
On the GroundWind erosion is a major resource concern for rangeland managers because it can impact soil health, ecosystem structure and function, hydrologic processes, agricultural production, and air quality.Despite its significance, little is known about which landscapes are eroding, by how much, and when.The National Wind Erosion Research...
Webb, Nicholas P.; Van Zee, Justin W.; Karl, Jason W.; Herrick, Jeffrey E.; Courtright, Ericha M.; Billings, Benjamin J.; Boyd, Robert C.; Chappell, Adrian; Duniway, Michael C.; Derner, Justin D.; Hand, Jenny L.; Kachergis, Emily; McCord, Sarah E.; Newingham, Beth A.; Pierson, Frederick B.; Steiner, Jean L.; Tatarko, John; Tedela, Negussie H.; Toledo, David; Van Pelt, R. Scott Hierarchical, quantitative biogeographic provinces for all North American turtles and their contribution to the biogeography of turtles and the continent
Our study represents the first attempt to describe biogeographic provinces for North American (México, United States, and Canada) turtles. We analyzed three nested data sets separately: (1) all turtles, (2) freshwater turtles, and (3) aquatic turtles. We georeferenced North American turtle distributions, then we created presence–absence matrices...
Ennen, Joshua R.; Matamoros, Wilfredo A.; Agha, Mickey; Lovich, Jeffrey E.; Sweat, Sarah C.; Hoagstrom, Christopher W. An evaluation of sampling and full enumeration strategies for Fisher Jenks classification in big data settings
Large data contexts present a number of challenges to optimal choropleth map classifiers. Application of optimal classifiers to a sample of the attribute space is one proposed solution. The properties of alternative sampling-based classification methods are examined through a series of Monte Carlo simulations. The impacts of spatial...
Rey, Sergio J.; Stephens, Philip A.; Laura, Jason R.
Geochemical characterization of groundwater discharging from springs north of the Grand Canyon, Arizona, 2009–2016
A geochemical study was conducted on 37 springs discharging from the Toroweap Formation, Coconino Sandstone, Hermit Formation, Supai Group, and Redwall Limestone north of the Grand Canyon near areas of breccia-pipe uranium mining. Baseline concentrations were established for the elements As, B, Li, Se, SiO2, Sr, Tl, U, and V. Three springs...
Beisner, Kimberly R.; Tillman, Fred D.; Anderson, Jessica R.; Antweiler, Ronald C.; Bills, Donald J. Evapotranspiration by remote sensing: An analysis of the Colorado River Delta before and after the Minute 319 pulse flow to Mexico
The unique hydrologic conditions characterizing riparian ecosystems in dryland (arid and semi-arid) areas help maintain high biodiversity and support high levels of primary productivity compared to associated uplands. In western North America, many riparian ecosystems have been damaged by altered flow regimes (e.g., impoundments and diversions)...
Jarchow, Christopher J.; Nagler, Pamela L.; Glenn, Edward P.; Ramirez-Hernandez, Jorge; Rodriguez-Burgueno, Eliana Greenup and evapotranspiration following the Minute 319 pulse flow to Mexico: An analysis using Landsat 8 Normalized Difference Vegetation Index (NDVI) data
In the southwestern U.S., many riparian ecosystems have been altered by dams, water diversions, and other anthropogenic activities. This is particularly true of the Colorado River, where numerous dams and agricultural diversions have affected this water course, especially south of the U.S.–Mexico border. In the spring of 2014, 130 million cubic...
Jarchow, Christopher J.; Nagler, Pamela L.; Glenn, Edward P. Competition amplifies drought stress in forests across broad climatic and compositional gradients
Forests around the world are experiencing increasingly severe droughts and elevated competitive intensity due to increased tree density. However, the influence of interactions between drought and competition on forest growth remains poorly understood. Using a unique dataset of stand-scale dendrochronology sampled from 6405 trees, we quantified how...
Gleason, Kelly; Bradford, John B.; Bottero, Alessandra; D'Amato, Tony; Fraver, Shawn; Palik, Brian J.; Battaglia, Michael; Iverson, Louis R.; Kenefic, Laura; Kern, Christel C. It takes more than water: Restoring the Colorado River Delta
Environmental flows have become important tools for restoring rivers and associated riparian ecosystems (Arthington, 2012; Glenn et al., 2017). In March 2014, the United States and Mexico initiated a bold effort in restoration, delivering from Morelos Dam a “pulse flow” of water into the Colorado River in its delta for the purpose of learning...
Pitt, Jennifer; Kendy, Eloise; Schlatter, Karen; Hinojosa-Huertaf, Osvel; Flessa, Karl W.; Shafroth, Patrick B.; Ramirez-Hernandez, Jorge; Nagler, Pamela L.; Glenn, Edward P.
White Pelicans
Birds found in and around the Salton Sea, California.
White Pelicans
Birds found in and around the Salton Sea, California.
White Pelicans
Birds found in and around the Salton Sea, California.
Ancient Lake Cahuilla High Water Mark
Lake Cahuilla was an ancient freshwater lake in the Salton Trough of southern California. It covered parts of the Coachella, Imperial and Mexicali valleys and was formed when the Colorado River overflowed its banks or was diverted northwest by its own sediments, which temporarily blocked the flow to the Gulf of California (Sea of Cortez). Although there have been a few
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Natural Bridges State Beach, Santa Cruz, California
Photograph of the coastal region of Natural Bridges State Beach in Santa Cruz, California
White Pelicans
Birds found in and around the Salton Sea, California.
Collecting Bathymetric Data in San Francisco Bay
USGS scientists Patrick Barnard (left) and Jeff Hansen navigate personal watercraft equipped with GPS and echo sounders through the waters of San Francisco Bay. They are collecting bathymetric, or depth, information in order to create maps of the bottom of the Bay. The maps will be used to determine how the morphology or shape of the Bay floor changes through time.
Great Egret Fishing
Birds found in and around the Salton Sea, California.
Roseate Spoonbill
Birds found in and around the Salton Sea, California.
Wood Stork with Fish
Birds found in and around the Salton Sea, California.
Wood Storks
Birds found in and around the Salton Sea, California.
Nine USGS Science Centers are administered by the Pacific Regional office, which is headquartered in Sacramento, California.
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Locations
Southwest Regional Director's Office
Phone: (916) 278-9551
Fax: (916) 278-9566
Pacific Coastal and Marine Science Center
Phone: 831-460-7401
Fax: 831-427-4748
Western Geographic Science Center - Main Office
Phone: (650) 329-5049
Earthquake Science Center
Geology, Minerals, Energy and Geophysics Science Center
Phone: (650) 329-4881
California Water Science Center - Sacramento Projects Office
Phone: (916) 278-3000
Fax: (916) 278-3070
Astrogeology Science Center
Phone: 928-556-7000
Fax: 928-556-7014
Nevada Water Science Center
Phone: (775) 887-7600
Fax: (775) 887-7629
Western Ecological Research Center - Headquarters
Phone: (916) 278-9485
Fax: (916) 278-9475
Arizona Water Science Center, Tucson Office
Phone: (520) 670-6671
Fax: (520) 670-5592
Southwest Biological Science Center - Flagstaff, AZ, Research Station
Phone: 928-556-7094
Fax: 928-556-7092