Larry Brown (Former Employee)
Science and Products
Filter Total Items: 125
Synthesis of studies in the fall low-salinity zone of the San Francisco Estuary, September-December 2011
In fall 2011, a large-scale investigation (fall low-salinity habitat investigation) was implemented by the Bureau of Reclamation in cooperation with the Interagency Ecological Program to explore hypotheses about the ecological role of low-salinity habitat in the San Francisco Estuary—specifically, hypotheses about the importance of fall low-salinity habitat to the biology of delta smelt...
Authors
Larry R. Brown, Randall Baxter, Gonzalo Castillo, Louise Conrad, Steven D. Culberson, Gregg Erickson, Frederick V. Feyrer, Stephanie Fong, Karen Gehrts, Lenny Grimaldo, Bruce Herbold, Joseph E. Kirsch, Anke Mueller-Solger, Steven J. Slater, Ted Sommer, Kelly Souza, Erwin E Van Nieuwenhuyse
Stream macroinvertebrate response models for bioassessment metrics: addressing the issue of spatial scale
We developed independent predictive disturbance models for a full regional data set and four individual ecoregions (Full Region vs. Individual Ecoregion models) to evaluate effects of spatial scale on the assessment of human landscape modification, on predicted response of stream biota, and the effect of other possible confounding factors, such as watershed size and elevation, on model...
Authors
Ian R. White, Jonathan Kennen, Jason May, Larry R. Brown, Thomas F. Cuffney, Kimberly A. Jones, James L. Orlando
Enriquillo–Plantain Garden fault zone in Jamaica: paleoseismology and seismic hazard
The countries of Jamaica, Haiti, and the Dominican Republic all straddle the Enriquillo–Plantain Garden fault zone ( EPGFZ), a major left-lateral, strike-slip fault system bounding the Caribbean and North American plates. Past large earthquakes that destroyed the capital cities of Kingston, Jamaica (1692, 1907), and Port-au-Prince, Haiti (1751, 1770), as well as the 2010 Haiti earthquake...
Authors
R.D. Koehler, P. Mann, Carol S. Prentice, Larry R. Brown, B. Benford, M. Grandison-Wiggins
Implications for future survival of delta smelt from four climate change scenarios for the Sacramento–San Joaquin Delta, California
Changes in the position of the low salinity zone, a habitat suitability index, turbidity, and water temperature modeled from four 100-year scenarios of climate change were evaluated for possible effects on delta smelt Hypomesus transpacificus, which is endemic to the Sacramento–San Joaquin Delta. The persistence of delta smelt in much of its current habitat into the next century appears...
Authors
Larry R. Brown, William A. Bennett, R. Wayne Wagner, Tara Morgan, Noah Knowles, Frederick V. Feyrer, David H. Schoellhamer, Mark T. Stacey, Michael D. Dettinger
Effects of urban development on stream ecosystems in nine metropolitan study areas across the United States
Urban development is an important agent of environmental change in the United States. The urban footprint on the American landscape has expanded during a century and a half of almost continuous development. Eighty percent of Americans now live in metropolitan areas, and the advantages and challenges of living in these developed areas—convenience, congestion, employment, pollution—are...
Authors
James F. Coles, Gerard McMahon, Amanda H. Bell, Larry R. Brown, Faith A. Fitzpatrick, Barbara C. Scudder Eikenberry, Michael D. Woodside, Thomas F. Cuffney, Wade B. Bryant, Karen Cappiella, Lisa Fraley-McNeal, William P. Stack
Upper Clear Creek watershed aquatic chemistry and biota surveys, 2004-5, Whiskeytown National Recreation Area, Shasta County, California
The U.S. Geological Survey, in cooperation with the National Park Service and Whiskeytown National Recreation Area, performed a comprehensive aquatic biota survey of the upper Clear Creek watershed, Shasta County, California, during 2004-5. Data collected in this study can provide resource managers with information regarding aquatic resources, watershed degradation, and regional...
Authors
Marissa L. Wulff, Jason May, Larry R. Brown
Predicting biological condition in southern California streams
As understanding of the complex relations among environmental stressors and biological responses improves, a logical next step is predictive modeling of biological condition at unsampled sites. We developed a boosted regression tree (BRT) model of biological condition, as measured by a benthic macroinvertebrate index of biotic integrity (BIBI), for streams in urbanized Southern Coastal...
Authors
Larry R. Brown, Jason May, Andrew C. Rehn, Peter R. Ode, Ian R. Waite, Jonathan Kennen
Comparison of stream invertebrate response models for bioassessment metric
We aggregated invertebrate data from various sources to assemble data for modeling in two ecoregions in Oregon and one in California. Our goal was to compare the performance of models developed using multiple linear regression (MLR) techniques with models developed using three relatively new techniques: classification and regression trees (CART), random forest (RF), and boosted...
Authors
Ian R. Waite, Jonathan Kennen, Jason May, Larry R. Brown, Thomas F. Cuffney, Kimberly A. Jones, James L. Orlando
Life histories, salinity zones, and sublethal contributions of contaminants to pelagic fish declines illustrated with a case study of San Francisco Estuary, California, USA
Human effects on estuaries are often associated with major decreases in abundance of aquatic species. However, remediation priorities are difficult to identify when declines result from multiple stressors with interacting sublethal effects. The San Francisco Estuary offers a useful case study of the potential role of contaminants in declines of organisms because the waters of its delta...
Authors
Marjorie L. Brooks, Erica Fleishman, Larry R. Brown, Peggy W. Lehman, Inge Werner, Nathaniel L. Scholz, Carys Michelmore, James R. Loworn, Michael Scott Johnson, Daniel Schlenk
Concentrations of mercury and other metals in black bass (Micropterus spp.) from Whiskeytown Lake, Shasta County, California, 2005
This report presents the results of a reconnaissance study conducted by the U.S. Geological Survey (USGS) to determine mercury (Hg) and other selected metal concentrations in Black bass (Micropterus spp.) from Whiskeytown Lake, Shasta County, California. Total mercury concentrations were determined by cold-vapor atomic absorption spectroscopy (CVAAS) in fillets and whole bodies of each...
Authors
Jason May, Roger L. Hothem, Marissa L. Bauer, Larry R. Brown
A perspective on modern pesticides, pelagic fish declines, and unknown ecological resilience in highly managed ecosystems
Pesticides applied on land are commonly transported by runoff or spray drift to aquatic ecosystems, where they are potentially toxic to fishes and other nontarget organisms. Pesticides add to and interact with other stressors of ecosystem processes, including surface-water diversions, losses of spawning and rearing habitats, nonnative species, and harmful algal blooms. Assessing the...
Authors
Nathaniel L. Scholz, Erica Fleishman, Larry R. Brown, Inge Werner, Michael Scott Johnson, Marjorie L. Brooks, Carys L. Mitchelmore, Daniel Schlenk
Associations of benthic macroinvertebrate assemblages with environmental variables in the upper Clear Creek watershed, California
Benthic macroinvertebrates are integral components of stream ecosystems and are often used to assess the ecological integrity of streams. We sampled streams in the upper Clear Creek drainage in the Klamath—Siskiyou Ecoregion of northwestern California in fall 2004 (17 sites) and 2005 (original 17 plus 4 new sites) with the objectives of documenting the benthic macroinvertebrate...
Authors
Larry R. Brown, Jason May, Marissa L. Wulff
Science and Products
Filter Total Items: 125
Synthesis of studies in the fall low-salinity zone of the San Francisco Estuary, September-December 2011
In fall 2011, a large-scale investigation (fall low-salinity habitat investigation) was implemented by the Bureau of Reclamation in cooperation with the Interagency Ecological Program to explore hypotheses about the ecological role of low-salinity habitat in the San Francisco Estuary—specifically, hypotheses about the importance of fall low-salinity habitat to the biology of delta smelt...
Authors
Larry R. Brown, Randall Baxter, Gonzalo Castillo, Louise Conrad, Steven D. Culberson, Gregg Erickson, Frederick V. Feyrer, Stephanie Fong, Karen Gehrts, Lenny Grimaldo, Bruce Herbold, Joseph E. Kirsch, Anke Mueller-Solger, Steven J. Slater, Ted Sommer, Kelly Souza, Erwin E Van Nieuwenhuyse
Stream macroinvertebrate response models for bioassessment metrics: addressing the issue of spatial scale
We developed independent predictive disturbance models for a full regional data set and four individual ecoregions (Full Region vs. Individual Ecoregion models) to evaluate effects of spatial scale on the assessment of human landscape modification, on predicted response of stream biota, and the effect of other possible confounding factors, such as watershed size and elevation, on model...
Authors
Ian R. White, Jonathan Kennen, Jason May, Larry R. Brown, Thomas F. Cuffney, Kimberly A. Jones, James L. Orlando
Enriquillo–Plantain Garden fault zone in Jamaica: paleoseismology and seismic hazard
The countries of Jamaica, Haiti, and the Dominican Republic all straddle the Enriquillo–Plantain Garden fault zone ( EPGFZ), a major left-lateral, strike-slip fault system bounding the Caribbean and North American plates. Past large earthquakes that destroyed the capital cities of Kingston, Jamaica (1692, 1907), and Port-au-Prince, Haiti (1751, 1770), as well as the 2010 Haiti earthquake...
Authors
R.D. Koehler, P. Mann, Carol S. Prentice, Larry R. Brown, B. Benford, M. Grandison-Wiggins
Implications for future survival of delta smelt from four climate change scenarios for the Sacramento–San Joaquin Delta, California
Changes in the position of the low salinity zone, a habitat suitability index, turbidity, and water temperature modeled from four 100-year scenarios of climate change were evaluated for possible effects on delta smelt Hypomesus transpacificus, which is endemic to the Sacramento–San Joaquin Delta. The persistence of delta smelt in much of its current habitat into the next century appears...
Authors
Larry R. Brown, William A. Bennett, R. Wayne Wagner, Tara Morgan, Noah Knowles, Frederick V. Feyrer, David H. Schoellhamer, Mark T. Stacey, Michael D. Dettinger
Effects of urban development on stream ecosystems in nine metropolitan study areas across the United States
Urban development is an important agent of environmental change in the United States. The urban footprint on the American landscape has expanded during a century and a half of almost continuous development. Eighty percent of Americans now live in metropolitan areas, and the advantages and challenges of living in these developed areas—convenience, congestion, employment, pollution—are...
Authors
James F. Coles, Gerard McMahon, Amanda H. Bell, Larry R. Brown, Faith A. Fitzpatrick, Barbara C. Scudder Eikenberry, Michael D. Woodside, Thomas F. Cuffney, Wade B. Bryant, Karen Cappiella, Lisa Fraley-McNeal, William P. Stack
Upper Clear Creek watershed aquatic chemistry and biota surveys, 2004-5, Whiskeytown National Recreation Area, Shasta County, California
The U.S. Geological Survey, in cooperation with the National Park Service and Whiskeytown National Recreation Area, performed a comprehensive aquatic biota survey of the upper Clear Creek watershed, Shasta County, California, during 2004-5. Data collected in this study can provide resource managers with information regarding aquatic resources, watershed degradation, and regional...
Authors
Marissa L. Wulff, Jason May, Larry R. Brown
Predicting biological condition in southern California streams
As understanding of the complex relations among environmental stressors and biological responses improves, a logical next step is predictive modeling of biological condition at unsampled sites. We developed a boosted regression tree (BRT) model of biological condition, as measured by a benthic macroinvertebrate index of biotic integrity (BIBI), for streams in urbanized Southern Coastal...
Authors
Larry R. Brown, Jason May, Andrew C. Rehn, Peter R. Ode, Ian R. Waite, Jonathan Kennen
Comparison of stream invertebrate response models for bioassessment metric
We aggregated invertebrate data from various sources to assemble data for modeling in two ecoregions in Oregon and one in California. Our goal was to compare the performance of models developed using multiple linear regression (MLR) techniques with models developed using three relatively new techniques: classification and regression trees (CART), random forest (RF), and boosted...
Authors
Ian R. Waite, Jonathan Kennen, Jason May, Larry R. Brown, Thomas F. Cuffney, Kimberly A. Jones, James L. Orlando
Life histories, salinity zones, and sublethal contributions of contaminants to pelagic fish declines illustrated with a case study of San Francisco Estuary, California, USA
Human effects on estuaries are often associated with major decreases in abundance of aquatic species. However, remediation priorities are difficult to identify when declines result from multiple stressors with interacting sublethal effects. The San Francisco Estuary offers a useful case study of the potential role of contaminants in declines of organisms because the waters of its delta...
Authors
Marjorie L. Brooks, Erica Fleishman, Larry R. Brown, Peggy W. Lehman, Inge Werner, Nathaniel L. Scholz, Carys Michelmore, James R. Loworn, Michael Scott Johnson, Daniel Schlenk
Concentrations of mercury and other metals in black bass (Micropterus spp.) from Whiskeytown Lake, Shasta County, California, 2005
This report presents the results of a reconnaissance study conducted by the U.S. Geological Survey (USGS) to determine mercury (Hg) and other selected metal concentrations in Black bass (Micropterus spp.) from Whiskeytown Lake, Shasta County, California. Total mercury concentrations were determined by cold-vapor atomic absorption spectroscopy (CVAAS) in fillets and whole bodies of each...
Authors
Jason May, Roger L. Hothem, Marissa L. Bauer, Larry R. Brown
A perspective on modern pesticides, pelagic fish declines, and unknown ecological resilience in highly managed ecosystems
Pesticides applied on land are commonly transported by runoff or spray drift to aquatic ecosystems, where they are potentially toxic to fishes and other nontarget organisms. Pesticides add to and interact with other stressors of ecosystem processes, including surface-water diversions, losses of spawning and rearing habitats, nonnative species, and harmful algal blooms. Assessing the...
Authors
Nathaniel L. Scholz, Erica Fleishman, Larry R. Brown, Inge Werner, Michael Scott Johnson, Marjorie L. Brooks, Carys L. Mitchelmore, Daniel Schlenk
Associations of benthic macroinvertebrate assemblages with environmental variables in the upper Clear Creek watershed, California
Benthic macroinvertebrates are integral components of stream ecosystems and are often used to assess the ecological integrity of streams. We sampled streams in the upper Clear Creek drainage in the Klamath—Siskiyou Ecoregion of northwestern California in fall 2004 (17 sites) and 2005 (original 17 plus 4 new sites) with the objectives of documenting the benthic macroinvertebrate...
Authors
Larry R. Brown, Jason May, Marissa L. Wulff
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government