Articles
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 65,000 articles 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: 77868
Ecological effects of climate-driven salinity variation in the San Francisco Estuary: Can we anticipate and manage the coming changes? Ecological effects of climate-driven salinity variation in the San Francisco Estuary: Can we anticipate and manage the coming changes?
Climate change-driven sea level rise and altered precipitation regimes are predicted to alter patterns of salt intrusion within the San Francisco Estuary. A central question is: Can we use existing knowledge and future projections to predict and manage the anticipated ecological impacts? This was the subject of a 2018 symposium entitled “Ecological and Physiological Impacts of...
Authors
Cameron K Chalambor, Edward S. Gross, Edwin D. Grosholz, Ken M Jeffries, John L. Largier, Stephen D. McCormick, Ted Sommer, Jonathan P Velotta, Andrew Whitehead
Improving species status assessments under the U.S. Endangered Species Act and implications for multispecies conservation challenges worldwide Improving species status assessments under the U.S. Endangered Species Act and implications for multispecies conservation challenges worldwide
Despite its successes, the U.S. Endangered Species Act (ESA) has proven challenging to implement due to funding limitations, workload backlog, and other problems. As threats to species survival intensify and as more species come under threat, the need for the ESA and similar conservation laws and policies in other countries to function efficiently has grown. Attempts by the U.S. Fish and...
Authors
Reed Noss, Jennifer M. Cartwright, Dwayne Estes, Theo Witsell, Gregg Elliott, Daniel S. Adams, Matthew A. Albrecht, Ryan Boyles, Patrick Comer, Chris Doffitt, JoVonn G. Hill, William C. Hunter, Wesley M. Knapp, Mike Marshall, Jason R. Singhurst, Christopher Tracey, Jeffrey L. Walck, Alan Weakley
Quantification of manganese for ChemCam Mars and laboratory spectra using a multivariate model Quantification of manganese for ChemCam Mars and laboratory spectra using a multivariate model
We report a new calibration model for manganese using the laser-induced breakdown spectroscopy instrument that is part of the ChemCam instrument suite onboard the NASA Curiosity rover. The model has been trained using an expanded set of 523 manganese-bearing rock, mineral, metal ore, and synthetic standards. The optimal calibration model uses the Partial Least Squares (PLS) and Least...
Authors
Patrick J. Gasda, Ryan B. Anderson, A. Cousin, O. Forni, S. M. Clegg, A. Ollila, Nina L. Lanza, S Lamm, Roger C. Wiens, Sylvestre Maurice, Olivier Gasnault, R. Beal, A. Reyes-Newell, D. Delapp
Reptile and amphibian diversity and abundance in an urban landscape: Impacts of fragmentation and the conservation value of small patches Reptile and amphibian diversity and abundance in an urban landscape: Impacts of fragmentation and the conservation value of small patches
Urbanization is a major contributor to habitat loss and fragmentation and is considered a global threat to biodiversity. We studied reptile and amphibian species diversity and abundance in a highly fragmented landscape adjacent to the second largest metropolitan area in the United States. Habitat patches in our study area were made up of remnant native vegetation surrounded by roads...
Authors
Kathleen Semple Delaney, Gary Busteed, Robert N. Fisher, Seth P.D. Riley
Perfluoroalkyl substances in plasma of smallmouth bass from the Chesapeake Bay Watershed Perfluoroalkyl substances in plasma of smallmouth bass from the Chesapeake Bay Watershed
Smallmouth bass Micropterus dolomieu is an economically important sportfish and within the Chesapeake Bay watershed has experienced a high prevalence of external lesions, infectious disease, mortality events, reproductive endocrine disruption and population declines. To date, no clear or consistent associations with contaminants measured in fish tissue or surface water have been found...
Authors
Vicki S. Blazer, Stephanie E. Gordon, Heather L. Walsh, Cheyenne R. Smith
Surface flow velocities from space: Particle image velocimetry of satellite video of a large, sediment-laden river Surface flow velocities from space: Particle image velocimetry of satellite video of a large, sediment-laden river
Conventional, field-based streamflow monitoring in remote, inaccessible locations such as Alaska poses logistical challenges. Safety concerns, financial considerations, and a desire to expand water-observing networks make remote sensing an appealing alternative means of collecting hydrologic data. In an ongoing effort to develop non-contact methods for measuring river discharge, we...
Authors
Carl J. Legleiter, Paul J. Kinzel
Floral resource selection by wild bees and honey bees in the Midwest United States: Implications for designing pollinator habitat Floral resource selection by wild bees and honey bees in the Midwest United States: Implications for designing pollinator habitat
Many seed mix recommendations for creating pollinator habitat are in part based on anecdotal evidence or field observations of bees visiting forbs (i.e. use). However, there is limited information on what forbs are preferred by bees, particularly in working landscapes where bee forage may be limited. We examined floral resource selection by wild bees and honey bees on grasslands in the...
Authors
Stacy C. Simanonok, Clint Otto, Deborah A. Buhl
Amplified impact of climate change on fine-sediment delivery to a subsiding coast, Humboldt Bay, California Amplified impact of climate change on fine-sediment delivery to a subsiding coast, Humboldt Bay, California
In Humboldt Bay, tectonic subsidence exacerbates sea-level rise (SLR). To build surface elevations and to keep pace with SLR, the sediment demand created by subsidence and SLR must be balanced by an adequate sediment supply. This study used an ensemble of plausible future scenarios to predict potential climate change impacts on suspended-sediment discharge (Qss) from fluvial sources...
Authors
Jennifer Curtis, Lorraine E. Flint, Michelle A. Stern, Jack Lewis, Randy D. Klein
Genomic signatures of thermal adaptation are associated with clinal shifts of life history in a broadly distributed frog Genomic signatures of thermal adaptation are associated with clinal shifts of life history in a broadly distributed frog
Temperature is a critical driver of ectotherm life-history strategies, whereby a warmer environment is associated with increased growth, reduced longevity and accelerated senescence. Increasing evidence indicates that thermal adaptation may underlie such life-history shifts in wild populations. Single nucleotide polymorphisms (SNPs) and copy number variants (CNVs) can help uncover the...
Authors
Hugo Cayuela, Yann Dorant, Brenna R. Forester, Dan L Jeffries, Rebecca M. McCaffery, Lisa A Eby, Blake R. Hossack, Jérôme M W Gippet, David S. Pilliod, W Chris Funk
Declining diversity of wild-caught species puts dietary nutrient supplies at risk Declining diversity of wild-caught species puts dietary nutrient supplies at risk
Although biodiversity loss adversely influences a variety of ecosystem functions, how declining wild food diversity affects nutrient supplies for people is poorly understood. Here, we analyze the impact of declining biodiversity on nutrients supplied by fish using detailed information from the Peruvian Amazon, where inland fisheries provide a critical source of nutrition for many of the...
Authors
Sebastian A. Heilpern, Ruth DeFries, Kathryn J. Fiorella, Alexander Flecker, Suresh Sethi, María Uriarte, Shahid Naeem
Use of the smeltCam as an efficient fish sampling alternative within the San Francisco Estuary Use of the smeltCam as an efficient fish sampling alternative within the San Francisco Estuary
Resource managers often rely on long-term monitoring surveys to detect trends in biological data. However, no survey gear is 100% efficient, and many sources of bias can be responsible for detecting or not detecting biological trends. The SmeltCam is an imaging apparatus developed as a potential sampling alternative to long-term trawling gear surveys within the San Francisco Estuary...
Authors
Brock Huntsman, Frederick V. Feyrer, Matthew J. Young
Predicting light regime controls on primary productivity across CONUS river networks Predicting light regime controls on primary productivity across CONUS river networks
Solar radiation is a fundamental driver of ecosystem productivity, but widespread estimates of light available for primary producers in rivers are lacking. We developed a model to predict light available for river primary producers and used it to estimate river primary production across the contiguous United States (CONUS). Successively accounting for riparian and water column processes...
Authors
Philip Savoy, Judson Harvey