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Publications

For more than a century, USGS scientists have conducted research in California’s Bay-Delta region. Informing natural-resource management decisions on the region’s issues, this research has been published in thousands of documents, some highlighted below.

Filter Total Items: 308

Estimating juvenile Chinook salmon (Oncorhynchus tshawytscha) abundance from beach seine data collected in the Sacramento–San Joaquin Delta and San Francisco Bay, California

Resource managers rely on abundance or density metrics derived from beach seine surveys to make vital decisions that affect fish population dynamics and assemblage structure. However, abundance and density metrics may be biased by imperfect capture and lack of geographic closure during sampling. Currently, there is considerable uncertainty about the capture efficiency of juvenile Chinook salmon (O
Authors
Russell W. Perry, Joseph E. Kirsch, A. Noble Hendrix

Earthquake outlook for the San Francisco Bay region 2014–2043

Using information from recent earthquakes, improved mapping of active faults, and a new model for estimating earthquake probabilities, the 2014 Working Group on California Earthquake Probabilities updated the 30-year earthquake forecast for California. They concluded that there is a 72 percent probability (or likelihood) of at least one earthquake of magnitude 6.7 or greater striking somewhere in
Authors
Brad T. Aagaard, J. Luke Blair, John Boatwright, Susan H. Garcia, Ruth A. Harris, Andrew J. Michael, David P. Schwartz, Jeanne S. DiLeo

Post-release survival and movement of Western Grebes (Aechmophorus occidentalis) implanted with intracoelomic satellite transmitters

The main goal of this study was to gain knowledge on post-release survival and movement of Western Grebes (Aechmophorus occidentalis) using a modified technique for implanting satellite transmitters. This technique had improved post-surgical survival in an earlier study. Nine Western Grebes, implanted with intracoelomic (within the body cavity) satellite transmitters with percutaneous antennae, we
Authors
Kyra L. Mills, Joseph K. Gaydos, Christine V. Fiorello, Emily Whitmer, Susan De La Cruz, Daniel M. Mulcahy, L. Ignacio Vilchis, Michael H. Ziccardi

@KarlTheFog has been mapped!

Within the world of mapping, clouds are a pesky interference to be removed from satellite remote sensed imagery.  However, to many of us, that is a waste of pixels. Cloud maps are becoming increasingly valuable in the quest to understand land cover change and surface processes. In coastal California, the dynamic summertime interactions between air masses, the ocean, and topography result in blanke
Authors
Alicia Torregrosa

Evaluation of Caspian tern (Hydroprogne caspia) and snowy plover (Charadrius alexandrinus nivosus) nesting on modified islands at the Don Edwards San Francisco Bay National Wildlife Refuge, California—2015 Annual Report

Executive Summary In order to address the 2008/10 NOAA Fisheries Biological Opinion for operation of the Federal Columbia River Power System, the U.S. Army Corps of Engineers (USACE) and the Bureau of Reclamation (Reclamation) have developed and begun implementation of Caspian tern (Hydroprogne caspia) management plans. This implementation includes relocating nesting Caspian terns out of the Colum
Authors
C. Alex Hartman, Joshua T. Ackerman, Mark P. Herzog, Cheryl Strong, David Trachtenbarg, Kimberley A. Sawyer, Crystal A. Shore

Linking hydrodynamic complexity to delta smelt (Hypomesus transpacificus) distribution in the San Francisco Estuary, USA

Long-term fish sampling data from the San Francisco Estuary were combined with detailed three dimensional hydrodynamic modeling to investigate the relationship between historical fish catch and hydrodynamic complexity. Delta Smelt catch data at 45 stations from the Fall Midwater Trawl (FMWT) survey in the vicinity of Suisun Bay were used to develop a quantitative catch-based station index. This in
Authors
Aaron J. Bever, Michael L. MacWilliams, Bruce Herbold, Larry R. Brown, Frederick V. Feyrer

Bivalve grazing can shape phytoplankton communities

The ability of bivalve filter feeders to limit phytoplankton biomass in shallow waters is well-documented, but the role of bivalves in shaping phytoplankton communities is not. The coupled effect of bivalve grazing at the sediment-water interface and sinking of phytoplankton cells to that bottom filtration zone could influence the relative biomass of sinking (diatoms) and non-sinking phytoplankton
Authors
Lisa Lucas, James E. Cloern, Janet K. Thompson, Mark T. Stacey, Jeffrey K. Koseff

Regional monitoring programs in the United States: Synthesis of four case studies from Pacific, Atlantic, and Gulf Coasts

Water quality monitoring is a cornerstone of environmental protection and ambient monitoring provides managers with the critical data they need to take informed action. Unlike site-specific monitoring that is at the heart of regulatory permit compliance, regional monitoring can provide an integrated, holistic view of the environment, allowing managers to obtain a more complete picture of natural v
Authors
Peter J. Tango, K. Schiff, P.R. Trowbridge, E.T. Sherwood, R.A. Batiuk

Endangered species management and ecosystem restoration: Finding the common ground

Management actions to protect endangered species and conserve ecosystem function may not always be in precise alignment. Efforts to recover the California Ridgway’s Rail (Rallus obsoletus obsoletus; hereafter, California rail), a federally and state-listed species, and restoration of tidal marsh ecosystems in the San Francisco Bay estuary provide a prime example of habitat restoration that has con
Authors
Michael L. Casazza, Cory T. Overton, Thuy-Vy D. Bui, Joshua M. Hull, Joy D. Albertson, Valary K. Bloom, Steven Bobzien, Jennifer McBroom, Marilyn Latta, Peggy Olofson, Tobias M. Rohmer, Steven E. Schwarzbach, Donald R. Strong, Erik Grijalva, Julian K. Wood, Shannon Skalos, John Y. Takekawa

Coupled downscaled climate models and ecophysiological metrics forecast habitat compression for an endangered estuarine fish

Climate change is driving rapid changes in environmental conditions and affecting population and species’ persistence across spatial and temporal scales. Integrating climate change assessments into biological resource management, such as conserving endangered species, is a substantial challenge, partly due to a mismatch between global climate forecasts and local or regional conservation planning.
Authors
Larry R. Brown, Lisa M Komoroske, R Wayne Wagner, Tara Morgan-King, Jason T. May, Richard E Connon, Nann A. Fangue

Bivalve effects on the food web supporting delta smelt - A long-term study of bivalve recruitment, biomass, and grazing rate patterns with varying freshwater outflow

Executive Summary Phytoplankton is an important and limiting food source in the Sacramento-San Joaquin Delta (the Delta) and San Francisco Bay; the decline of phytoplankton biomass is one possible factor in the pelagic organism decline and specifically in the decline of the protected delta smelt. The bivalves Corbicula fluminea andPotamocorbula amurensis have been shown to control phytoplankton bi
Authors
Jeff S. Crauder, Janet K. Thompson, Francis Parchaso, Rosa I. Anduaga, Sarah A. Pearson, Karen Gehrts, Heather Fuller, Elizabeth Wells

Recent advances in understanding flow dynamics and transport of water-quality constituents in the Sacramento–San Joaquin River Delta

This paper, part of the collection of research comprising the State of Bay–Delta Science 2016, describes advances during the past decade in understanding flow dynamics and how water-quality constituents move within California’s Sacramento– San Joaquin River Delta (Delta). Water-quality constituents include salinity, heat, oxygen, nutrients, contaminants, organic particles, and inorganic particles.
Authors
David H. Schoellhamer, Scott A. Wright, Stephen G. Monismith, Brian A. Bergamaschi