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2012

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Adaptive Management To Protect Biodiversity: Best Available Science And The Endangered Species Act, Olivia Odom Green, Ahjond S. Garmestani Jan 2012

Adaptive Management To Protect Biodiversity: Best Available Science And The Endangered Species Act, Olivia Odom Green, Ahjond S. Garmestani

United States Environmental Protection Agency: Publications

Although flawed, the most powerful tool for protecting biodiversity in the United States is the Endangered Species Act, which requires the use of the best available science to ensure that endangered and threatened species are not put in jeopardy of extinction. Unfortunately, the best available science mandate is virtually meaningless and imposes no additional scientific rigor in agency decision making beyond what is normally required of administrative procedures. In this paper, we propose to define best available science in a way that shifts from a way of using science to a way of doing science, and a sound method of …

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Chapter 1 An Introduction To Agricultural Biotechnology Regulation In The U.S., Chris A. Wozniak, Annabel Fellman Waggoner, Sheryl Reilly Jan 2012

Chapter 1 An Introduction To Agricultural Biotechnology Regulation In The U.S., Chris A. Wozniak, Annabel Fellman Waggoner, Sheryl Reilly

United States Environmental Protection Agency: Publications

The regulation of agricultural plant and microbial biotechnology products in the United States of America has a rich history that re fl ects the challenges the federal government has faced in the development of appropriate rules and standards needed to determine their safety to humans and the environment. Several factors – the insuf fi cient global food supply, loss or curtailment of the use of older chemistries to control pests due to risks and environmental persistence, the rising demand for safer food commodities, and the uncertainty surrounding the sustainability of agriculture in this and other countries – have added to …

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The Mouse: An‘‘Average’’Homeotherm, Christopher J. Gordon Jan 2012

The Mouse: An‘‘Average’’Homeotherm, Christopher J. Gordon

United States Environmental Protection Agency: Publications

Mice, rats, and nearly all mammals and birds are classified as homeothermic, meaning that their core temperature is regulated at a constant level over a relatively wide range of ambient temperatures. In one sense, this homeothermic designation has been confirmed by the advent of radiotelemetry and other techniques that allow for the remote monitoring of awake, unrestrained animals in laboratory or natural settings. This technology confirmed that, when averaged over many hours, core temperature of mammals is regulated at a nearly constant level. On the other hand, telemetric sampling in relatively small mammals such as mice and rats also revealed …

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Neurological Impacts From Inhalation Of Pollutants And The Nose–Brain Connection, R.G. Lucchini, D.C. Dorman, A. Elder, B. Veronesi Jan 2012

Neurological Impacts From Inhalation Of Pollutants And The Nose–Brain Connection, R.G. Lucchini, D.C. Dorman, A. Elder, B. Veronesi

United States Environmental Protection Agency: Publications

The effects of inhaled particles have focused heavily on the respiratory and cardiovascular systems. Most studies have focused on inhaled metals, whereas less information is available for other particle types regarding the effects on the brain and other extra-pulmonary organs. We review here the key available literature on nanoparticle uptake and transport through the olfactory pathway, the experimental data from animal and in vitro studies, and human epidemiological observations. Nanoparticles (<0.1µm in one dimension) may easily reach the brain from the respiratory tract via sensory neurons and transport from the distal alveoli into the blood or lymph as free particles or inside phagocytic cells. These mechanisms and subsequent biologic responses may be influenced by the chemical composition of inhaled particles. Animal studies with ambient particulate matter and certain other particles show alterations in neuro-inflammatory markers of oxidative stress and central neurodegeneration. Human observations indicate motor, cognitive, and behavioral changes especially after particulate metal exposure in children. Exposure to co-pollutants and/or underlying disease states could also impact both the biokinetics and effects of airborne particles in the brain. Data are needed from the areas of inhalation, neurology, and metal toxicology in experimental and human studies after inhalation exposure. An increased understanding of the neurotoxicity associated with air pollution exposure is critical to protect susceptible individuals in the workplace and the general population.

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Immunomodulation In Eastern Oysters, Crassostrea Virginica, Exposed To A Pah-Contaminated, Microphytobenthic Diatom, April N. Croxton, Gary H. Wikfors, Richard D. Schulterbrandt-Gragg Jan 2012

Immunomodulation In Eastern Oysters, Crassostrea Virginica, Exposed To A Pah-Contaminated, Microphytobenthic Diatom, April N. Croxton, Gary H. Wikfors, Richard D. Schulterbrandt-Gragg

United States Department of Commerce: Staff Publications

The trophic transfer of sediment-associated pollutants is a growing concern in shellfish harvesting areas. Previous studies have examined the role of phytoplankton in the transport of organic contaminants to bivalve species, but little information on microphytobenthic communities and their role as contaminant vectors exists. Polycyclic aromatic hydrocarbons (PAHs) are organic compounds formed during natural and industrial processes; they are termed “persistent organic pollutants” because they are only slowly degraded by natural processes. This study examined the transfer of PAH compounds (naphthalene, pyrene, and benzo(a)pyrene) by a microphytobenthic diatom to the eastern oyster, a commercially important shellfish species, to determine if …

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Social Network Correlates Of Food Availability In An Endangered Population Of Killer Whales, Orcinus Orca, Emma A. Foster, Daniel W. Franks, Lesley J. Morrell, Ken C. Balcomb, Kim M. Parsons, Astrid Van Ginneken, Darren P. Croft Jan 2012

Social Network Correlates Of Food Availability In An Endangered Population Of Killer Whales, Orcinus Orca, Emma A. Foster, Daniel W. Franks, Lesley J. Morrell, Ken C. Balcomb, Kim M. Parsons, Astrid Van Ginneken, Darren P. Croft

United States Department of Commerce: Staff Publications

For the majority of social species, group composition is dynamic, and individuals are interconnected in a heterogeneous social network. Social network structure has far-reaching implications for the ecology of individuals and populations. However, we have little understanding of how ecological variables shape this structure. We used a long-term data set (1984e2007) to examine the relationship between food availability and social network structure in the endangered southern resident killer whales. During the summer months individuals in this population feed primarily on chinook salmon, Oncorhynchus tshawytscha, which show annual variation in abundance. We tested the hypothesis that temporal variation in chinook …

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Coupling Planktonic Ecosystem And Fisheries Food Web Models For A Pelagic Ecosystem: Description And Validation For The Subarctic Pacific, Kelly A. Kearney, Charles Stock, Kerim Aydin, Jorge L. Sarmiento Jan 2012

Coupling Planktonic Ecosystem And Fisheries Food Web Models For A Pelagic Ecosystem: Description And Validation For The Subarctic Pacific, Kelly A. Kearney, Charles Stock, Kerim Aydin, Jorge L. Sarmiento

United States Department of Commerce: Staff Publications

We provide a modeling framework that fully couples a one-dimensional physical mixed layer model, a biogeochemical model, and an upper trophic level fisheries model. For validation purposes, the model has been parameterized for the pelagic Eastern Pacific Subarctic Gyre ecosystem. This paper presents a thorough description of the model itself, as well as an ensemble-based parameterization process that allows the model to incorporate the high level of uncertainty associated with many upper trophic level predator-prey processes. Through a series of model architecture experiments, we demonstrate that the use of a consistent functional response for all predator-prey interactions, as well as …

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Starvation Causes Disturbance In Amino Acid And Fatty Acid Metabolism In Diporeia, Suman Maity, Amber Jannasch, Jiri Adamec, Thomas Nalepa, Tomas O. Höök, Maria S. Sepúlveda Jan 2012

Starvation Causes Disturbance In Amino Acid And Fatty Acid Metabolism In Diporeia, Suman Maity, Amber Jannasch, Jiri Adamec, Thomas Nalepa, Tomas O. Höök, Maria S. Sepúlveda

United States Department of Commerce: Staff Publications

The benthic amphipod Diporeia spp. was once the predominant macroinvertebrate in deep, offshore regions of the Laurentian Great Lakes. However, since the early 1990s, Diporeia populations have steadily declined across the area. It has been hypothesized that this decline is due to starvation from increasing competition for food with invasive dreissenid mussels. In order to gain a better understanding of the changes in Diporeia physiology during starvation, we applied two-dimensional gas chromatography coupled with time of flight mass spectrometry (GCXGC/TOF-MS) for investigating the responses in Diporeia metabolome during starvation. We starved Diporeia for 60 days and collected five organisms every …

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Health Status, Infection And Disease In California Sea Lions (Zalophus Californianus) Studied Using A Canine Microarray Platform And Machine-Learning Approaches, Annalaura Mancia, James C. Ryan, Robert W. Chapman, Qingzhong Wu, Gregory W. Warr, Frances M.D. Gulland, Frances M. Van Dolah Jan 2012

Health Status, Infection And Disease In California Sea Lions (Zalophus Californianus) Studied Using A Canine Microarray Platform And Machine-Learning Approaches, Annalaura Mancia, James C. Ryan, Robert W. Chapman, Qingzhong Wu, Gregory W. Warr, Frances M.D. Gulland, Frances M. Van Dolah

United States Department of Commerce: Staff Publications

Conservation biologists face many challenges in assessing health, immune status and infectious diseases in protected species. These challenges include unpredictable sample populations, diverse genetic and environmental backgrounds of the animals, as well as the practical, legal and ethical issues involved in experimentation. The use of whole genome scale transcriptomics with animal samples obtained in a minimally invasive manner is an approach that shows promise for health assessment. In this study we assessed the utility of a microarray to identify changes in gene expression predictive of health status by interrogating blood samples from California sea lions (Zalophus californianus) in …

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The Development Of A New Optical Total Suspended Matter Algorithm For The Chesapeake Bay, Michael Ondrusek, Eric Stengel, Christopher Kinkade, Ronald Vogel, Phillip Keegstra, Craig Hunter, Chunai Kim Jan 2012

The Development Of A New Optical Total Suspended Matter Algorithm For The Chesapeake Bay, Michael Ondrusek, Eric Stengel, Christopher Kinkade, Ronald Vogel, Phillip Keegstra, Craig Hunter, Chunai Kim

United States Department of Commerce: Staff Publications

Sediment loading is one of the primary threats to the health of the Chesapeake Bay.We have developed a high resolution (250 m) ocean color satellite tool to monitor sediment concentrations in the Bay. In situ optical and sediment sampling is used to develop a total suspended matter (TSM) algorithm for the Chesapeake Bay. The Coastal Optical Characterization Experiment (COCE) is part of an ongoing effort to optically characterize processes and to develop regional remote sensing ocean color algorithms in the coastalwaters. The goal is to characterize sediment concentrations and to develop a tool to track plumes cascading down the Bay …

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Water Properties In Chesapeake Bay From Modis-Aqua Measurements, Seunghyun Son, Menghua Wang Jan 2012

Water Properties In Chesapeake Bay From Modis-Aqua Measurements, Seunghyun Son, Menghua Wang

United States Department of Commerce: Staff Publications

This study evaluates the performance of ocean color products derived from measurements of the Moderate Resolution Imaging Spectro-radiometer (MODIS) on the satellite Aqua using the standard near-infrared (NIR) and the shortwave infrared (SWIR)-based atmospheric correction algorithms in the Chesapeake Bay. The MODIS-Aquaderived normalized water-leaving radiances, nLw(λ), and chlorophyll-a (Chl-a) data are comparedwith in situ radiometric measurements fromtheNASA SeaWiFS Bio-opticalArchive and Storage System(SeaBASS) database and Chl-a data from the Chesapeake Bay Water Quality Database. Results show that, using the NIR-SWIR combined ocean color data processing, improved nLw(λ) and Chl-a data products can be produced in …

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Prototype For Monitoring And Forecasting Fall Foliage Coloration In Real Time From Satellite Data, Xiaoyang Zhang, Mitchell D. Goldberg, Yunyue Yu Jan 2012

Prototype For Monitoring And Forecasting Fall Foliage Coloration In Real Time From Satellite Data, Xiaoyang Zhang, Mitchell D. Goldberg, Yunyue Yu

United States Department of Commerce: Staff Publications

While determining vegetation phenology from the time series of historical satellite data has been widely investigated throughout the last decade, little effort has been devoted to real-time monitoring and shortterm forecasting. The latter is more important for numerical weather modeling, ecosystem forecasting, forest and crop management, and health risk warning. In this study we developed a prototype approach for the real-time monitoring and short-term forecasting of fall foliage status (including low coloration, moderate coloration, near-peak coloration, peak coloration, and post-peak coloration) using temporal satellite observations. The algorithm combined the climatology of vegetation phenology and temporally available satellite observations to establish …

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Prototype For Monitoring And Forecasting Fall Foliage Coloration In Real Time From Satellite Data, Xiaoyang Zhang, Mitchell D. Goldberg, Yunyue Yu Jan 2012

Prototype For Monitoring And Forecasting Fall Foliage Coloration In Real Time From Satellite Data, Xiaoyang Zhang, Mitchell D. Goldberg, Yunyue Yu

United States Department of Commerce: Staff Publications

While determining vegetation phenology from the time series of historical satellite data has been widely investigated throughout the last decade, little effort has been devoted to real-time monitoring and shortterm forecasting. The latter is more important for numerical weather modeling, ecosystem forecasting, forest and crop management, and health risk warning. In this study we developed a prototype approach for the real-time monitoring and short-term forecasting of fall foliage status (including low coloration, moderate coloration, near-peak coloration, peak coloration, and post-peak coloration) using temporal satellite observations. The algorithm combined the climatology of vegetation phenology and temporally available satellite observations to establish …

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Mercury In The Gulf Of Mexico: Sources To Receptors, Reed Harris, Curtis Pollman, William Landing, David Evans, Donald Axelrad, David Hutchinson, Steven L. Morey, Darren Rumbold, Dmitry Dukhovskoy, Douglas H. Adams, Krish Vijayaraghavan, Christopher Holmes, R. Dwight Atkinson, Tom Myers, Elsie Sunderland Jan 2012

Mercury In The Gulf Of Mexico: Sources To Receptors, Reed Harris, Curtis Pollman, William Landing, David Evans, Donald Axelrad, David Hutchinson, Steven L. Morey, Darren Rumbold, Dmitry Dukhovskoy, Douglas H. Adams, Krish Vijayaraghavan, Christopher Holmes, R. Dwight Atkinson, Tom Myers, Elsie Sunderland

United States Department of Commerce: Staff Publications

Gulf of Mexico (Gulf) fisheries account for 41% of the U.S. marine recreational fish catch and 16% of the nation's marine commercial fish landings. Mercury (Hg) concentrations are elevated in some fish species in the Gulf, including king mackerel, sharks, and tilefish. All five Gulf states have fish consumption advisories based on Hg. Per-capita fish consumption in the Gulf region is elevated compared to the U.S. national average, and recreational fishers in the region have a potential for greater MeHg exposure due to the higher levels of fish consumption. Atmospheric we Hg deposition is estimated to be higher in the …

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Pharmaceuticals And Personal Care Products (Ppcps) In Treated Wastewater Discharges Into Charleston Harbor, South Carolina, Melanie Lea Hedgespeth, Yelena Sapozhnikova, Paul Pennington, Allan Clum, Andy Fairey, Edward Wirth Jan 2012

Pharmaceuticals And Personal Care Products (Ppcps) In Treated Wastewater Discharges Into Charleston Harbor, South Carolina, Melanie Lea Hedgespeth, Yelena Sapozhnikova, Paul Pennington, Allan Clum, Andy Fairey, Edward Wirth

United States Department of Commerce: Staff Publications

This study assessed seasonal and regional trends of pharmaceuticals and personal care products (PPCPs) detected in monthly samples from two local wastewater treatment plants (WWTPs) in Charleston, South Carolina, USA, over the period of one year. Surface water of Charleston Harbor was also analyzed to examine environmental distribution in an estuarine ecosystem. Of the 19 compounds examined, 11 were quantified in wastewater influent, 9 in effluent, and 7 in surface water. Aqueous concentrations of many PPCPs were reduced by >86% in wastewater effluent compared with influent, though some compounds showed low removal and greater effluent concentrations compared with influent (e.g. …

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Characterization Of Turbidity In Florida’S Lake Okeechobee And Caloosahatchee And St. Lucie Estuaries Using Modis-Aqua Measurements, Menghua Wang, Carl J. Nim, Seunghyun Son, Wei Shi Jan 2012

Characterization Of Turbidity In Florida’S Lake Okeechobee And Caloosahatchee And St. Lucie Estuaries Using Modis-Aqua Measurements, Menghua Wang, Carl J. Nim, Seunghyun Son, Wei Shi

United States Department of Commerce: Staff Publications

This paper describes the use of ocean color remote sensing data from the Moderate Resolution Imaging Spectroradiometer (MODIS) onboard the Aqua satellite to characterize turbidity in Lake Okeechobee and its primary drainage basins, the Caloosahatchee and St. Lucie estuaries from 2002 to 2010. Drainage modification and agricultural development in southern Florida transport sediments and nutrients from watershed agricultural areas to Lake Okeechobee. As a result of development around Lake Okeechobee and the estuaries that are connected to Lake Okeechobee, estuarine conditions have also been adversely impacted, resulting in salinity and nutrient fluctuations. The measurement of water turbidity in lacustrine and …

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Spatial And Temporal Patterns Of Vertical Distribution For Three Planktivorous Fishes In Lake Washington, Thomas P. Quinn, Christopher J. Sergeant, Anne H. Beaudreau, David A. Beauchamp Jan 2012

Spatial And Temporal Patterns Of Vertical Distribution For Three Planktivorous Fishes In Lake Washington, Thomas P. Quinn, Christopher J. Sergeant, Anne H. Beaudreau, David A. Beauchamp

United States Department of Commerce: Staff Publications

We sampled three limnetic fish species: juvenile sockeye salmon (Oncorhynchus nerka), three-spine stickleback (Gasterosteus aculeatus) and longfin smelt (Spirinchus thaleichthys) in Lake Washington to quantify species-specific patterns of diel vertical migration (DVM). Catch-per-unit-effort data analysed from 15 years of midwater trawling documented seasonal and diel differences in vertical distributions for each species. These results were consistent with the hypothesis that the patterns of DVM in Lake Washington were affected by life history, size and morphology. Sockeye salmon showed clear DVM in spring but essentially no DVM in fall, remaining in deep water, whereas three-spine …

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Assessment Of Management To Mitigate Anthropogenic Effects On Large Whales, Julie M. Van Der Hoop, Michael J. Moore, Susan G. Barco, Timothy V.N. Cole, Pierre-Yves Daoust, Allison G. Henry, Donald F. Mcalpine, William A. Mclellan, Tonya Wimmer, Andrew R. Solow Jan 2012

Assessment Of Management To Mitigate Anthropogenic Effects On Large Whales, Julie M. Van Der Hoop, Michael J. Moore, Susan G. Barco, Timothy V.N. Cole, Pierre-Yves Daoust, Allison G. Henry, Donald F. Mcalpine, William A. Mclellan, Tonya Wimmer, Andrew R. Solow

United States Department of Commerce: Staff Publications

United States and Canadian governments have responded to legal requirements to reduce human induced whale mortality via vessel strikes and entanglement in fishing gear by implementing a suite of regulatory actions. We analyzed the spatial and temporal patterns of mortality of large whales in the Northwest Atlantic (23.5°N to 48.0°N), 1970 through 2009, in the context of management changes. We used a multinomial logistic model fitted by maximum likelihood to detect trends in cause-specific mortalities with time. We compared the number of human-caused mortalities with U.S. federally established levels of potential biological removal (i.e., species-specific sustainable human-caused mortality). From 1970 …

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Sea-Level History Of Past Interglacial Periods From Uranium-Series Dating Of Corals, Curaçao, Leeward Antilles Islands, Daniel R. Muhs, John M. Pandolfi, Kathleen R. Simmons, R. Randall Schumann Jan 2012

Sea-Level History Of Past Interglacial Periods From Uranium-Series Dating Of Corals, Curaçao, Leeward Antilles Islands, Daniel R. Muhs, John M. Pandolfi, Kathleen R. Simmons, R. Randall Schumann

United States Geological Survey: Staff Publications

Curaçao has reef terraces with the potential to provide sea-level histories of interglacial periods. Ages of the Hato (upper) unit of the “Lower Terrace” indicate that this reef dates to the last interglacial period, Marine Isotope Stage (MIS) 5.5. On Curaçao, this high sea stand lasted at least 8000 yr (~126 to ~118 ka). Elevations and age of this reef show that late Quaternary uplift rates on Curaçao are low, 0.026–0.054 m/ka, consistent with its tectonic setting. Ages of ~200 ka for corals from the older Cortalein unit of the Lower Terrace correlate this reef to MIS 7, with paleo-sea …

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Missed Visits And Decline In Cd4 Cell Count Among Hiv-Infected Patients: A Mixed Method Study, Anna Walburn, Susan Swindles, Christopher Fisher, Robin High, K. M. Islam Jan 2012

Missed Visits And Decline In Cd4 Cell Count Among Hiv-Infected Patients: A Mixed Method Study, Anna Walburn, Susan Swindles, Christopher Fisher, Robin High, K. M. Islam

Uniformed Services University of the Health Sciences

Objective: To determine the impact of missed visits on CD4 cell count with HIV disease in a Midwest clinic. Methods: This was a mixed method study consisting of a quantitative retrospective cohort study of missed clinic visits among HIV-infected patients, and a qualitative study to collect information on factors impacting appointment attendance. A drop in CD4 cell count greater than 50 cells/mm3 from baseline was the primary outcome variable for the quantitative study. The exposure variable was missed visits. Results: Of 77 patients, 16.4% experienced the outcome of interest. Lower visit proportions increased the risk of a CD4 drop (hazard …

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Do Initial Responses To Drugs Predict Future Use Or Abuse?, Harriet De Wit, Tamara J. Phillips Jan 2012

Do Initial Responses To Drugs Predict Future Use Or Abuse?, Harriet De Wit, Tamara J. Phillips

United States Department of Veterans Affairs: Publications

Individuals vary in their initial reactions to drugs of abuse in ways that may contribute to the likelihood of subsequent drug use. In humans, most drugs of abuse produce positive subjective states such as euphoria and feelings of well-being, which may facilitate repeated use. In nonhumans, many drugs initially increase locomotor activity and produce discriminative stimulus effects, both of which have been considered to be models of human stimulant and subjective states. Both humans and nonhumans vary in their sensitivity to early acute drug effects in ways that may predict future use or self-administration, and some of these variations appear …

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A Brief History And Summary Of The Effects Of River Engineering And Dams On The Mississippi River System And Delta, Jason S. Alexander, Richard C. Wilson, W. Reed Green Jan 2012

A Brief History And Summary Of The Effects Of River Engineering And Dams On The Mississippi River System And Delta, Jason S. Alexander, Richard C. Wilson, W. Reed Green

United States Geological Survey: Water Reports and Publications

The United States Geological Survey Forecast Mekong project is providing technical assistance and information to aid management decisions and build science capacity of institutions in the Mekong River Basin. A component of this effort is to produce a synthesis of the effects of dams and other engineering structures on large-river hydrology, sediment transport, geomorphology, ecology, water quality, and deltaic systems. The Mississippi River Basin (MRB) of the United States was used as the backdrop and context for this synthesis because it is a continental scale river system with a total annual water discharge proportional to the Mekong River, has been …

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Field Experiment Provides Ground Truth For Surface Nuclear Magnetic Resonance Measurement, Rosemary Knight, Elliot Grunewald, Trevor Irons, Katherine Dlubac, Yiqiao Song, Henry N. Bachman, Ben Grau, Dave Walsh, Jared D. Abraham, Jim Cannia Jan 2012

Field Experiment Provides Ground Truth For Surface Nuclear Magnetic Resonance Measurement, Rosemary Knight, Elliot Grunewald, Trevor Irons, Katherine Dlubac, Yiqiao Song, Henry N. Bachman, Ben Grau, Dave Walsh, Jared D. Abraham, Jim Cannia

United States Geological Survey: Staff Publications

The need for sustainable management of fresh water resources is one of the great challenges of the 21st century. Since most of the planet’s liquid fresh water exists as groundwater, it is essential to develop non-invasive geophysical techniques to characterize groundwater aquifers. A field experiment was conducted in the High Plains Aquifer, central United States, to explore the mechanisms governing the non-invasive Surface NMR (SNMR) technology. We acquired both SNMR data and logging NMR data at a field site, along with lithology information from drill cuttings. This allowed us to directly compare the NMR relaxation parameter measured during logging, T …

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Dynamics Of Plains Cottonwood (Populus Deltoides) Forests And Historical Landscape Change Along Unchannelized Segments Of The Missouri River, Usa, Mark D. Dixon, W. Carter Johnson, Michael L. Scott, Daniel E. Bowen, Lisa A. Rabbe Jan 2012

Dynamics Of Plains Cottonwood (Populus Deltoides) Forests And Historical Landscape Change Along Unchannelized Segments Of The Missouri River, Usa, Mark D. Dixon, W. Carter Johnson, Michael L. Scott, Daniel E. Bowen, Lisa A. Rabbe

United States Geological Survey: Staff Publications

Construction of six large dams and reservoirs on the Missouri River over the last 50–75 years has resulted in major landscape changes and alterations in flow patterns, with implications for riparian forests dominated by plains cottonwood (Populus deltoides). We quantified changes in land cover from 1892–1950s and the 1950s– 2006 and the current extent and age structure of cottonwood forests on seven segments (two reservoir and five remnant floodplain) comprising 1127 km (53 %) of the unchannelized upper two-thirds of the Missouri River. Riparian forest area declined by 49 %; grassland 61 %; shrubland 52 %; and sandbar …

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Soil Genesis On The Island Of Bermuda In The Quaternary: The Importance Of African Dust Transport And Deposition, Daniel R. Muhs, James R. Budahn, Joseph M. Prospero, Gary Skipp, Stanley R. Herwitz Jan 2012

Soil Genesis On The Island Of Bermuda In The Quaternary: The Importance Of African Dust Transport And Deposition, Daniel R. Muhs, James R. Budahn, Joseph M. Prospero, Gary Skipp, Stanley R. Herwitz

United States Geological Survey: Staff Publications

The origin of terra rossa, red or reddish-brown, clay-rich soils overlying high-purity carbonate substrates, has intrigued geologists and pedologists for decades. Terra rossa soils can form from accumulation of insoluble residues during dissolution of the host limestones, addition of volcanic ash, or addition of externally derived, long-range-transported (LRT) aeolian particles. We studied soils and paleosols on high-purity, carbonate aeolianites of Quaternary age on Bermuda, where terra rossa origins have been debated for more than a century. Potential soil parent materials on this island include sand-sized fragments of local volcanic bedrock, the LRT, fine-grained (µm) component of distal loess from the …

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East Versus West: Organic Contaminant Differences In Brown Pelican (Pelecanus Occidentalis) Eggs From South Carolina, Usa And The Gulf Of California, Mexico, Stacy S. Vander Pol, Daniel W. Anderson, Patrick G.R. Jodice, Joyce E. Stuckey Jan 2012

East Versus West: Organic Contaminant Differences In Brown Pelican (Pelecanus Occidentalis) Eggs From South Carolina, Usa And The Gulf Of California, Mexico, Stacy S. Vander Pol, Daniel W. Anderson, Patrick G.R. Jodice, Joyce E. Stuckey

United States Geological Survey: Staff Publications

Brown pelicans (Pelecanus occidentalis) were listed as endangered in the United States in 1970, largely due to reproductive failure and mortality caused by organochlorine contaminants, such as DDT. The southeast population, P.o. carolinensis, was delisted in 1985, while the west coast population, P.o. californicus, was not delisted until 2009. As fish-eating coastal seabirds, brown pelicans may serve as a biomonitors. Organic contaminants were examined in brown pelican eggs collected from the Gulf of California in 2004 and South Carolina in 2005 using gas chromatography/mass spectrometry (GC/MS). Contaminants were compared using all individual data as well as …

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Critique On The Use Of The Standardized Avian Acute Oral Toxicity Test For First Generation Anticoagulant Rodenticides, Nimish B. Vyas, Barnett A. Rattner Jan 2012

Critique On The Use Of The Standardized Avian Acute Oral Toxicity Test For First Generation Anticoagulant Rodenticides, Nimish B. Vyas, Barnett A. Rattner

United States Geological Survey: Staff Publications

Avian risk assessments for rodenticides are often driven by the results of standardized acute oral toxicity tests without regards to a toxicant’s mode of action and time course of adverse effects. First generation anticoagulant rodenticides (FGARs) generally require multiple feedings over several days to achieve a threshold concentration in tissue and cause adverse effects. This exposure regimen is much different than that used in the standardized acute oral toxicity test methodology. Median lethal dose values derived from standardized acute oral toxicity tests underestimate the environmental hazard and risk of FGARs. Caution is warranted when FGAR toxicity, physiological effects, and pharmacokinetics …

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Climate Change And Infectious Disease Dynamics, Raina K. Plowright, Paul C. Cross, Gary M. Tabor, Emily Almberg, Leslie Bienen, Peter J. Hudson Jan 2012

Climate Change And Infectious Disease Dynamics, Raina K. Plowright, Paul C. Cross, Gary M. Tabor, Emily Almberg, Leslie Bienen, Peter J. Hudson

United States Geological Survey: Staff Publications

The International Panel on Climate Change has made an unequivocal case that the earth's climate is changing in profound ways, and that human activities are contributing significantly to climate disruption (IPCC 2007). The weight of evidence demonstrates warming global temperatures, changing patterns of precipitation, and increasing climate variability, with more extreme events. Thus, the physical underpinnings of ecology are changing, with pervasive effects on disease dynamics. Interactions among environment, hosts, and pathogens drive disease processes, and climate change will influence every interaction in this triad, directly and indirectly.

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Wildlife Toxicology: Environmental Contaminants And Their National And International Regulation, K. Christiana Grim, Anne Fairbrother, Barnett A. Rattner Jan 2012

Wildlife Toxicology: Environmental Contaminants And Their National And International Regulation, K. Christiana Grim, Anne Fairbrother, Barnett A. Rattner

United States Geological Survey: Staff Publications

Wildlife toxicology is the study of potentially harmful effects of toxic agents in wild animals, focusing on amphibians, reptiles, birds, and mammals. Fish and aquatic invertebrates are not usually included as part of wildlife toxicology since they fall within the field of aquatic toxicology, but collectively both disciplines often provide inSight into one another and both are integral parts of ecotoxicology (Hoffman et al. 2003). It entails monitoring, hypothesis testing, forensics, and risk assessment; encompasses molecular through ecosystem responses and various research venues (laboratory, mesocosm, field); and has been shaped by chemical use and misuse, ecological mishaps, and biomedical research. …

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Sorta Situ: The New Reality Of Management Conditions For Wildlife Populations In The Absence Of "Wild" Spaces, Barbara A. Wolfe, Roberto F. Aguilar, A. Alonso Aguirre, Glenn H. Olsen, Evan S. Blumer Jan 2012

Sorta Situ: The New Reality Of Management Conditions For Wildlife Populations In The Absence Of "Wild" Spaces, Barbara A. Wolfe, Roberto F. Aguilar, A. Alonso Aguirre, Glenn H. Olsen, Evan S. Blumer

United States Geological Survey: Staff Publications

The rate of species loss today is approaching catastrophic levels. Scientists project that over the next two decades, more than 1 million species of plants and animals will become extinct. E.O. Wilson has estimated that "the rate ofloss may exceed 50,000 a year, 137 a day ... this rate, while horrendous, is actually the minimal estimate, based on the species/area relationship alone" (Kellert and Wilson 1993, p. 16; Aguirre 2009). Ever-expanding communities, strained natural resources, changes in land use, and other anthropogenic drivers are compromising ecosystems and rapidly changing the landscape and the availability of "wild" spaces.

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