Reports
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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.
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Simulation of water-management scenarios for the Mississippi Delta Simulation of water-management scenarios for the Mississippi Delta
To compare the effectiveness of proposed alternative water-supply scenarios on future water availability in the Mississippi Delta, the U.S. Geological Survey and the Mississippi Department of Environmental Quality are collaborating on the update and enhancement of an existing regional groundwater-flow model of the area. Through this collaboration, the model has been updated to include...
Authors
Connor J. Haugh, Courtney D. Killian, Jeannie R. B. Barlow
Final project memorandum: Identifying conservation objectives for the Gulf Coast habitats of the black skimmer and gull-billed tern Final project memorandum: Identifying conservation objectives for the Gulf Coast habitats of the black skimmer and gull-billed tern
Many shorebirds and nearshore waterbirds are of conservation concern across the Gulf of Mexico due to stressors such as human disturbance, predation, and habitat loss and degradation. Conservation and protection of these birds is important for the functioning of healthy ecosystems and for maintaining biodiversity in North America. Consequently, resource managers along the Gulf need...
Authors
James P. Cronin
Pacific Continental Shelf Environmental Assessment (PaCSEA): Characterization of Seasonal Water Masses within the Northern California Current System Using Airborne Remote Sensing off Northern California, Oregon, and Washington, 2011–2012 Pacific Continental Shelf Environmental Assessment (PaCSEA): Characterization of Seasonal Water Masses within the Northern California Current System Using Airborne Remote Sensing off Northern California, Oregon, and Washington, 2011–2012
Here, we use ocean color measurements (Figure 1) and sea surface temperature (SST) data collected using sensors mounted on low-flying aircraft to characterize NCCS water masses and identify patterns among seasons and between years. To accomplish this, we applied k-means clustering to measured and derived ecologically-relevant physical and bio-optical variables (SST, Chla, absorbance by...
Authors
J A Schulien, Josh Adams, Jonathan J. Felis
Extending seasonal discharge records for streamgage sites on the North Fork Fortymile and Middle Fork Fortymile Rivers, Alaska, through water year 2019 Extending seasonal discharge records for streamgage sites on the North Fork Fortymile and Middle Fork Fortymile Rivers, Alaska, through water year 2019
Daily mean discharge values were estimated for May 20–September 30 for 1976–82 and 2006–18 for the U.S. Geological Survey North Fork Fortymile River and Middle Fork Fortymile River streamgage sites in Alaska. A relation between study streamgage discharge and discharge for an index streamgage on the main-stem Fortymile River for a concurrent period in 2019 was developed using the...
Authors
Janet H. Curran
Predictive relations between acid-base chemistry and fish assemblages in streams of the Adirondack Mountains Predictive relations between acid-base chemistry and fish assemblages in streams of the Adirondack Mountains
Surface waters across much of New York State’s Adirondack Mountains were acidified in the late 20th century but began to recover following the 1990 Title IV Amendments to the Clean Air Act. Previous assessments of acidification recovery in the Adirondacks have generally been based on surface water chemistry data and inferred relationships to fish and other aquatic biota. Little data...
Authors
Diane Bertok, Barry P. Baldigo, Scott D. George
Habitat affinities and at-sea ranging behaviors among main Hawaiian Island seabirds: Breeding seabird telemetry, 2013–2016 Habitat affinities and at-sea ranging behaviors among main Hawaiian Island seabirds: Breeding seabird telemetry, 2013–2016
Recent Hawaiʻi state clean energy policy mandates and federal interest in developing offshore renewable energy resources have prompted unsolicited lease requests for offshore wind energy infrastructure (OWEI) to be located in ocean waters off Hawaiʻi. This study describing at-sea ranging behaviors for five seabirds was intended to provide new information on Hawaiian breeding seabird...
Authors
Josh Adams, Jonathan J. Felis, Max Czapanskiy
A system design for implementing advanced feature descriptions for a map knowledge base A system design for implementing advanced feature descriptions for a map knowledge base
A prototype system to explore Linked Data that semantically integrates geospatial data in various formats from different publication sources with data from The National Map of the U.S. Geological Survey is presented. The focus is on accessing advanced feature descriptions for data from The National Map with data coreferenced from other sources. The prototype uses Geoserver to access The...
Authors
Matthew Wagner, Dalia E. Varanka, E. Lynn Usery
Evaluation of survey methods for colonial waterbirds at Chase Lake National Wildlife Refuge, North Dakota Evaluation of survey methods for colonial waterbirds at Chase Lake National Wildlife Refuge, North Dakota
Estimating the number of breeding pairs in a mixed-species waterbird colony is difficult because colonial waterbirds are vulnerable to human intrusion and their colonies are often in remote areas with limited access. We investigated methods to estimate the number of nests of waterbirds at a large, mixed-species colony at Chase Lake National Wildlife Refuge in south-central North Dakota...
Authors
Lawrence D. Igl, Alisa J. Bartos, Robert O. Woodward, Paulette Scherr, Marsha A. Sovada
Numerical simulation of groundwater availability in central Moloka‘i, Hawai‘i Numerical simulation of groundwater availability in central Moloka‘i, Hawai‘i
Since the 1990s, increased chloride concentrations of water pumped from wells (much of which is used for drinking water) and the effects of withdrawals on groundwater-dependent ecosystems have led to concerns over groundwater availability on the island of Molokaʻi, Hawaiʻi. An improved understanding of the hydrologic effects of proposed groundwater withdrawals is needed to ensure...
Authors
Delwyn S. Oki, John A. Engott, Kolja Rotzoll
Hawaiian hoary bat (Lasiurus cinereus semotus) acoustic monitoring at Hawaii Army National Guard (HIARNG) installations statewide Hawaiian hoary bat (Lasiurus cinereus semotus) acoustic monitoring at Hawaii Army National Guard (HIARNG) installations statewide
Acoustic sampling for occurrence of the endangered Hawaiian hoary bat (Lasiurus cinereus semotus) was conducted at 18 “long-term” acoustic monitoring stations on 12 Hawai‘i Army National Guard (HIARNG) installations across the islands of Hawai‘i, Maui, Moloka‘i, O‘ahu, and Kaua‘i between 2012 and 2018. Bats were confirmed as present at 10 of these installations: Kealakekua Armory...
Authors
Kristina Montoya-Aiona, Corinna Pinzari, Robert W. Peck, Kevin W. Brinck, Frank J Bonaccorso
Assessing the spawning movement and habitat needs of riverine Neosho Smallmouth Bass Assessing the spawning movement and habitat needs of riverine Neosho Smallmouth Bass
Stream fishes are vulnerable to a variety of natural and anthropogenic stressors. Information on fish movements and habitat use is essential to conserve and manage populations, particularly at the edges of distributions and novel habitats. The Neosho Smallmouth Bass Micropterus dolomieu velox is endemic to the southwestern Ozark Highlands ecoregion, where the riverscape is highly...
Authors
Shannon K. Brewer, Andrew Miller
Potential duration of aftershocks of the 2020 southwestern Puerto Rico earthquake Potential duration of aftershocks of the 2020 southwestern Puerto Rico earthquake
Abstract Aftershocks (earthquakes clustered spatially and chronologically near the occurrence of a causative earthquake) are ongoing in southwestern Puerto Rico after a series of earthquakes, which include a magnitude 6.4 earthquake that occurred near Barrio Indios, Guayanilla, on January 7, 2020, and affected the surrounding area. This report estimates the expected duration of these...
Authors
Nicholas van der Elst, Jeanne L. Hardebeck, Andrew J. Michael