Reports
Science Quality and Integrity
The USGS provides unbiased, objective, and impartial scientific information upon which our audiences, including resource managers, planners, and other entities, rely.
The USGS provides unbiased, objective, and impartial scientific information upon which our audiences, including resource managers, planners, and other entities, rely.
Browse more than 82,000 reports authored by our scientists over the past 100+ year history of the USGS and refine search by topic, location, year, and advanced search.
Filter Total Items: 85089
National wildlife refuge visitor survey 2012--Individual refuge results National wildlife refuge visitor survey 2012--Individual refuge results
The National Wildlife Refuge System (Refuge System), established in 1903 and managed by the U.S. Fish and Wildlife Service (Service), is the leading network of protected lands and waters in the world dedicated to the conservation of fish, wildlife and their habitats. There are 560 national wildlife refuges and 38 wetland management districts nationwide, encompassing more than 150 million...
Authors
Alia M. Dietsch, Natalie R. Sexton, Lynne M. Koontz, Shannon J. Conk
Native and nonnative fish populations of the Colorado River are food limited--evidence from new food web analyses Native and nonnative fish populations of the Colorado River are food limited--evidence from new food web analyses
Fish populations in the Colorado River downstream from Glen Canyon Dam appear to be limited by the availability of high-quality invertebrate prey. Midge and blackfly production is low and nonnative rainbow trout in Glen Canyon and native fishes in Grand Canyon consume virtually all of the midge and blackfly biomass that is produced annually. In Glen Canyon, the invertebrate assemblage is...
Authors
Theodore A. Kennedy, Wyatt F. Cross, Robert O. Hall, Colden V. Baxter, Emma J. Rosi-Marshall
Native Prairie Adaptive Management: a multi region adaptive approach to invasive plant management on Fish and Wildlife Service owned native prairies Native Prairie Adaptive Management: a multi region adaptive approach to invasive plant management on Fish and Wildlife Service owned native prairies
Much of the native prairie managed by the U.S. Fish and Wildlife Service (FWS) in the Prairie Pothole Region (PPR) of the northern Great Plains is extensively invaded by the introduced cool-season grasses, smooth brome (Bromus inermis) and Kentucky bluegrass (Poa pratensis). Management to suppress these invasive plants has had poor to inconsistent success. The central challenge to...
Authors
Jill J. Gannon, Terry L. Shaffer, Clinton T. Moore
Natural Hazards Science at the U.S. Geological Survey Natural Hazards Science at the U.S. Geological Survey
The mission of the USGS in natural hazards is to develop and apply hazard science to help protect the safety, security, and economic well-being of the Nation. The costs and consequences of natural hazards can be enormous, and each year more people and infrastructure are at risk. The USGS conducts hazard research and works closely with stakeholders and cooperators to inform a broad range...
Authors
Suzanne C. Perry, Lucile M. Jones, Robert R. Holmes
Natural-color and color-infrared image mosaics of the Colorado River corridor in Arizona derived from the May 2009 airborne image collection Natural-color and color-infrared image mosaics of the Colorado River corridor in Arizona derived from the May 2009 airborne image collection
The Grand Canyon Monitoring and Research Center (GCMRC) of the U.S. Geological Survey (USGS) periodically collects airborne image data for the Colorado River corridor within Arizona (fig. 1) to allow scientists to study the impacts of Glen Canyon Dam water release on the corridor’s natural and cultural resources. These data are collected from just above Glen Canyon Dam (in Lake Powell)...
Authors
Philip A. Davis
Naturally occurring contaminants in the Piedmont and Blue Ridge crystalline-rock aquifers and Piedmont Early Mesozoic basin siliciclastic-rock aquifers, eastern United States, 1994–2008 Naturally occurring contaminants in the Piedmont and Blue Ridge crystalline-rock aquifers and Piedmont Early Mesozoic basin siliciclastic-rock aquifers, eastern United States, 1994–2008
Groundwater quality and aquifer lithologies in the Piedmont and Blue Ridge Physiographic Provinces in the eastern United States vary widely as a result of complex geologic history. Bedrock composition (mineralogy) and geochemical conditions in the aquifer directly affect the occurrence (presence in rock and groundwater) and distribution (concentration and mobility) of potential naturally...
Authors
Melinda J. Chapman, Charles A. Cravotta, Zoltan Szabo, Bruce D. Lindsay
Nature's Notebook 2012: State of the data Nature's Notebook 2012: State of the data
In 2012, 2,045 observers contributed 1,592 sites to the NPDb, encompassing all 50 states, the U.S. Virgin Islands, and Puerto Rico. At the close of 2012 the NPDb contained a total of over 1.6 million phenophase status records. More than half of these records were submitted in 2012. Observers submitted records on 547 species in 2012, including 371 plant species (comprised of 5,584...
Authors
Jherime Kellermann, T.M. Crimmins, E.G. Denny, C.A.F. Enquist, K.L. Gerst, A.H. Rosemartin, Jake F. Weltzin
Near-field receiving water monitoring of trace metals and a benthic community near the Palo Alto Regional Water Quality Control Plant in south San Francisco Bay, California, 2012 Near-field receiving water monitoring of trace metals and a benthic community near the Palo Alto Regional Water Quality Control Plant in south San Francisco Bay, California, 2012
Trace-metal concentrations in sediment and in the clam Macoma petalum (formerly reported as Macoma balthica), clam reproductive activity, and benthic macroinvertebrate community structure were investigated in a mudflat 1 kilometer south of the discharge of the Palo Alto Regional Water Quality Control Plant (PARWQCP) in South San Francisco Bay, Calif. This report includes the data...
Authors
Jessica Dyke, Janet K. Thompson, Daniel J. Cain, Amy E. Kleckner, Francis Parcheso, Samuel N. Luoma, Michelle I. Hornberger
Nearshore temperature findings for the Colorado River in Grand Canyon, Arizona: Possible implications for native fish Nearshore temperature findings for the Colorado River in Grand Canyon, Arizona: Possible implications for native fish
Since the completion of Glen Canyon Dam, Arizona, in 1963, downstream water temperatures in the main channel of the Colorado River in Glen, Marble, and Grand Canyons are much colder in summer. This has negatively affected humpback chub (Gila cypha) and other native fish adapted to seasonally warm water, reducing main-channel spawning activity and impeding the growth and development of...
Authors
Robert P. Ross, William S. Vernieu
Nearshore thermal gradients of the Colorado River near the Little Colorado River confluence, Grand Canyon National Park, Arizona, 2010 Nearshore thermal gradients of the Colorado River near the Little Colorado River confluence, Grand Canyon National Park, Arizona, 2010
Construction and operation of Glen Canyon Dam has dramatically impacted the flow of the Colorado River through Glen, Marble, and Grand Canyons. Extremes in both streamflow and water temperature have been suppressed by controlled releases from the dam. Trapping of sediment in Lake Powell, the reservoir formed by Glen Canyon Dam, has also dramatically reduced the supply of suspended...
Authors
Rob Ross, Paul E. Grams
New service interface for River Forecasting Center derived quantitative precipitation estimates New service interface for River Forecasting Center derived quantitative precipitation estimates
For more than a decade, the National Weather Service (NWS) River Forecast Centers (RFCs) have been estimating spatially distributed rainfall by applying quality-control procedures to radar-indicated rainfall estimates in the eastern United States and other best practices in the western United States to producea national Quantitative Precipitation Estimate (QPE) (National Weather Service...
Authors
David L. Blodgett
New vitrinite reflectance data for the Wind River Basin, Wyoming New vitrinite reflectance data for the Wind River Basin, Wyoming
The Wind River Basin is a large Laramide (Late Cretaceous through Eocene) structural and sedimentary basin that encompasses about 7,400 square miles in central Wyoming. The basin is bounded by the Washakie Range and Owl Creek and southern Bighorn Mountains on the north, the Casper arch on the east and northeast, and the Granite Mountains on the south, and Wind River Range on the west...
Authors
Mark J. Pawlewicz, Thomas M. Finn