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USGS2016

Science to support aquatic animal health

Healthy aquatic ecosystems are home to a diversity of plants, invertebrates, fish and wildlife. Aquatic animal populations face unprecedented threats to their health and survival from climate change, water shortages, habitat alteration, invasive species and environmental contaminants. These environmental stressors can directly impact the prevalence and severity of disease in aquatic populations. For example, periodic fish kills in the upper Chesapeake Bay Watershed are associated with many different opportunistic pathogens that proliferate in stressed fish populations. An estimated 80 percent of endangered juvenile Puget Sound steelhead trout die within two weeks of entering the marine environment, and a role for disease in these losses is being investigated. The introduction of viral hemorrhagic septicemia virus (VHSV) into the Great Lakes—a fishery worth an estimated 7 billion dollars annually—resulted in widespread fish die-offs and virus detections in 28 different fish species. Millions of dying sea stars along the west coast of North America have led to investigations into sea star wasting disease. U.S. Geological Survey (USGS) scientists are assisting managers with these issues through ecological investigations of aquatic animal diseases, field surveillance, and research to promote the development of mitigation strategies.

Fact Sheet↗

USGS2018

Information to prevent human exposure to disease agents associated with wildlife—U.S. Geological Survey circulars on zoonotic disease

The U.S. Geological Survey in collaboration with the U.S. Fish and Wildlife Service and others have published reports with information about geographic distribution, specific pathogens, disease ecology, and strategies to avoid exposure and infection for a selection of zoonotic diseases. Zoonotic diseases are diseases that can be passed from animals to humans, such as rabies and plague. This summary factsheet highlights the reports on plague, bat rabies, and raccoon roundworm with links to all seven zoonotic diseases covered in this series.

Fact Sheet↗

USGS2019

Escherichia coli in the Santa Cruz River in Tumacácori National Historical Park, Arizona

At Tumacácori National Historical Park in southern Arizona, resource managers are concerned about microbial pathogens in the Santa Cruz River that could pose a serious health risk to employees and visitors. The U.S. Geological Survey recently completed a comprehensive 3-year study of water quality in the Santa Cruz River watershed that investigated the possible sources of microbial contamination and how it relates to the amount of water and suspended sediment in the river. The results of this study help water managers and park administration better address this contamination and issue warnings to the public when the water is unsafe.

Arizona↗

USGS2024

Invasive species research—Science for prevention, detection, containment, and control

Introduction Invasive species research within the U.S. Geological Survey’s (USGS) Ecosystems Mission Area focuses on invasive plants, animals, and pathogens throughout the United States. USGS scientists provide science support to help solve the problems posed by these nonnative species while working with partners in the U.S. Department of the Interior (DOI), other Federal, State, and Territorial agencies, Tribes, industry, agriculture, and nonprofit organizations. Key components of USGS invasive species science include the development of novel prevention, prediction, early detection, containment, and control tools.

Fact Sheet↗

USGS2025

USGS—An Unparalleled Scientific Asset

The U.S. Geological Survey (USGS) delivers information critical to powering our economy, managing our natural resources, and keeping Americans safe and healthy. 1 Mapping the Nation $21B Geologic maps save users an estimated 15% in annual costs: a value of between $14B and $21B. $25.6B in annual value to users of imagery from Landsat satellites, which were codeveloped by NASA and the USGS and operated through their lifespans by the USGS. $13.5B in annual benefits is generated by the USGS's 3D Elevation Program. Securing America’s Energy Independence 44% USGS-identified undiscovered geothermal energy is equal to 44% of current U.S. electricity generation. 29.4B barrels of oil and 391.6 trillion cubic feet of gas in recoverable resources are available on U.S. public lands based on USGS assessments. Protecting Americans’ Health and Safety $424B in recent wildland fire damages highlight the need for USGS fire science, which supports efforts to protect communities and reduce risk. USGS earthquake, volcano, landslide, and coastal hazard monitoring and information save lives and minimize costs; for example, $2.8M can be saved because of USGS enhanced information about a Mauna Loa eruption. $4.5B is the estimated cost of annual flooding. Through a network of over 11,885 streamgages, the USGS supports public safety and enables forecasts, early warning systems, and management actions that protect lives and property. Supporting National Security $3.1B The USGS identified a $3.1B risk to the American economy if China restricts gallium imports. This is one example underscoring the importance of the USGS mapping critical minerals, investigating supply chains, and producing the Nation’s critical minerals list. Enhancing Our Lands and Waters $21B in estimated annual costs results from invasive species. The USGS’s invasive species research informs approaches used to reduce their effects on agriculture, water infrastructure, disease transmission, fisheries, and outdoor recreation. USGS innovations support early warnings for harmful algal blooms—over $2M in yearly benefits are provided to Kansas alone. $45B USGS science informs the management of big game (such as deer and elk). The big-game hunting industry contributes $45B to the U.S. economy. Fostering American Prosperity $4.1T Mineral commodities are necessary for the $4.1T in value added to the GDP by major industries that consume processed mineral materials and employ 1 million workers. Because of this, USGS data on mineral supply, demand, and trade are highly valued. 45,000 metric tons Rare earths power the growing technology economy, including cell phones, electric vehicles, and medical devices. For over 70 years, USGS work has supported the discovery of rare earth resources in California’s Mountain Pass area, which produced 45,000 metric tons of rare earth concentrates in 2024—over 11% of the global supply. Guarding American Food Security $70.2B USGS science informs early warning systems and management strategies to mitigate disease outbreaks in agriculture—critical research on highly pathogenic avian influenza, for example, helps safeguard the $70B value in poultry and egg production. $11.8B USGS groundwater tools are vital for agriculture; for example, in the Mississippi Alluvial Plain, 65% of farming relies on groundwater to support its $11.8B annual industry. 1 Values throughout are given in billions (B), millions (M), and trillions (T) of U.S. dollars. GDP is “Gross Domestic Product.” Percentages are shown as %.

General Information Product↗

USGS2003

Investigation of the possible connection of rock and soil geochemistry to the occurrence of high rates of neurodegenerative diseases on Guam and a hypothesis for the cause of the diseases

High incidences of neurodegenerative diseases, mainly dementia, parkinsonism, and amyotrophic lateral sclerosis, occur on the island of Guam (Koerner, 1952; Kurland and Mulder, 1954). The occurrence and description of the diseases and a summary of the investigations can be found in Perl (1997). The diseases have been more prevalent along the southern coast, particularly the small villages of Umatac, Merizo, and Inarajan (Reed and Brody, 1975; Roman, 1996; and Perl, 1997) (fig. 1), and referred to as the southern villages in this report. Tertiary volcanic rocks underlie most of the southern part of the island, including these villages. The northern part of Guam, with lower incidences of the diseases, consists of carbonate rocks. Epidemiological studies beginning in the early 1950’s failed to show the cause to be genetic etiology (Plato and others, 1986; Zhang and others, 1990). In recent studies, the search for pathogenic mechanisms has shifted to environmental factors. Excesses or deficiencies of various elements from dietary sources including drinking water can have an effect on human health. These deficiencies or excesses can usually be attributed to the geochemical composition of the rocks and derived soils that underlie the area. An example is the high concentration of Se in soil associated with the occurrence of selenosis in adults (Mills, 1996). Yase (1972) suggested that the neurodegenerative diseases on Guam may be related to accumulation of trace elements such as manganese and aluminum, both of which may cause neurodegeneration. It has been suggested that a deficiency in calcium and magnesium in the soil and water along with readily available aluminum could be connected to the occurrence of the diseases (Gajdusek, 1982; Yanagihara and others, 1984; Garruto and others, 1989). Some of the studies investigated metal exposure, particularly aluminum and manganese, and deficiencies in calcium and magnesium (Garruto and others, 1984). Aluminum has been shown to have neurotoxic effects (MacDonald and Martin, 1988), and aluminum has been implicated in the pathogenesis of Alzheimer’s disease and similar dementia by Perl and others (1982). Studies of soils developed on volcanic rocks on Guam and other islands by McLachlan and others (1989) found that soils on Guam averaged 42-fold higher yield of elutable aluminum than soils developed on volcanic rocks on Jamaica or Palau. They did not detect unusually high dietary aluminum or low dietary calcium, but concluded that the soils and possibly the dusts of Guam might be a major source of aluminum entering the body of the inhabitants. This study was conducted to investigate the geochemistry of the soils and rocks of the volcanic southern part of the island of Guam, particularly in the vicinity of the three southern villages (Umatac, Merizo, and Inarajan) with high incidences of the diseases. In addition to total chemical analyses of the soils and rocks, various extractions of soils were carried out. Both excesses and deficiencies of various elements were looked for. Because soluble aluminum in the soil was shown by McLachlan and others (1989) to be unusually high, water-soluble extractions as well as sequential extractions of the soils were carried out. In addition, elements such as aluminum found in dust can traverse the nose-brain barrier in experimental animals (Sunderman, 2000) and respiratory epithelium is known to contain the highest concentration of aluminum in the human body (Tipton and others, 1957). The availability of elements, particularly aluminum from human inhalation of dust, derived from soil, was investigated. The available elements were determined by extractions of soils using a simulated lung-fluid extraction. In order to compare the results of the chemical data of rocks and soils from Guam to other rocks and soils elsewhere, samples of similar rocks and soils were collected in the western United States and similar analyses to those for the Guam samples carried out. The complete chemical analyses of the soils, rocks, and streambed sediments as well as descriptions of the methods used can be found in Miller and others (2002).

Open-File Report↗

USGS2007

Bacteria and emerging chemical contaminants in the St. Clair River/Lake St. Clair Basin, Michigan

Introduction Since the enactment of the Clean Water Act in 1972, awareness of the quality of the Nation's water has continued to improve. Despite improvements to wastewater-treatment systems and increased regulation on waste discharge, bacterial and chemical contamination is still a problem for many rivers and lakes throughout the United States. Pathogenic microorganism and newly recognized chemical contaminants have been found in waters that are used for drinking water and recreation (Rose and Grimes, 2001; Kolpin and others, 2002). This summary of bacteria and emerging-chemical-contaminant monitoring in the St. Clair River/Lake St. Clair Basin (fig. 1) was initiated by the Lake St. Clair Regional Monitoring Project (LSCRMP) in 2003, in cooperation with the Michigan Department of Environmental Quality (MDEQ), the Counties of Macomb, Oakland, St. Clair, and Wayne, and the U.S. Geological Survey (USGS).

Michigan↗

USGS2008

Study design and percent recoveries of anthropogenic organic compounds with and without the addition of ascorbic acid to preserve water samples containing free chlorine, 2004-06

The National Water-Quality Assessment (NAWQA) Program of the U.S. Geological Survey (USGS) began implementing Source Water-Quality Assessments (SWQAs) in 2002 that focus on characterizing the quality of source water and finished water of aquifers and major rivers used by some of the larger community water systems in the United States. As used for SWQA studies, source water is the raw (ambient) water collected at the supply well prior to water treatment (for ground water) or the raw (ambient) water collected from the river near the intake (for surface water). Finished water is the water that is treated, which typically involves, in part, the addition of chlorine or other disinfection chemicals to remove pathogens, and is ready to be delivered to consumers. Finished water is collected before the water enters the distribution system. This report describes the study design and percent recoveries of anthropogenic organic compounds (AOCs) with and without the addition of ascorbic acid to preserve water samples containing free chlorine. The percent recoveries were determined by using analytical results from a laboratory study conducted in 2004 by the USGS's National Water Quality Laboratory (NWQL) and from data collected during 2004-06 for a field study currently (2008) being conducted by the USGS's NAWQA Program. The laboratory study was designed to determine if preserving samples with ascorbic acid (quenching samples) adversely affects analytical performance under controlled conditions. During the laboratory study, eight samples of reagent water were spiked for each of five analytical schedules evaluated. Percent recoveries from these samples were then compared in two ways: (1) four quenched reagent spiked samples analyzed on day 0 were compared with four quenched reagent spiked samples analyzed on day 7 or 14, and (2) the combined eight quenched reagent spiked samples analyzed on day 0, 7, or 14 were compared with eight laboratory reagent spikes (LRSs). Percent recoveries from the quenched reagent spiked samples that were analyzed at two different times (day 0 and day 7 or 14) can be used to determine the stability of the quenched samples held for an amount of time representative of the normal amount of time between sample collection and analysis. The comparison between the quenched reagent spiked samples and the LRSs can be used to determine if quenching samples adversely affects the analytical performance under controlled conditions. The field study began in 2004 and is continuing today (February 2008) to characterize the effect of quenching on field-matrix spike recoveries and to better understand the potential oxidation and transformation of 277 AOCs. Three types of samples were collected from 11 NAWQA Study Units across the Nation: (1) quenched finished-water samples (not spiked), (2) quenched finished-water spiked samples, and (3) nonquenched finished-water spiked samples. Percent recoveries of AOCs in quenched and nonquenched finished-water spiked samples collected during 2004-06 are presented. Comparisons of percent recoveries between quenched and nonquenched spiked samples can be used to show how quenching affects finished-water samples. A maximum of 6 surface-water and 7 ground-water quenched finished-water spiked samples paired with nonquenched finished-water spiked samples were analyzed. Analytical results for the field study are presented in two ways: (1) by surface-water supplies or ground-water supplies, and (2) by use (or source) group category for surface-water and ground-water supplies. Graphical representations of percent recoveries for the quenched and nonquenched finished-water spiked samples also are presented.

Open-File Report↗

USGS2010

Microbial and geochemical investigations of dissolved organic carbon and microbial ecology of native waters from the Biscayne and Upper Floridan Aquifers

Groundwater resources in the United States are under ever-increasing demands for potable, irrigation, and recreational uses. Additionally, aquifer systems are being used or targeted for use as storage areas for treated surface waters and (or) groundwaters via injection (for example, aquifer storage and recovery). To date, the influence that the nutrients, including carbon, in the injected water have on native microbial communities and the biogeochemistry in the subsurface zones used for storage of the injectate has not been determined. In this report, we describe a series of experiments that establishes a baseline dataset for the quantity and quality of organic and inorganic carbon and nutrients in the Biscayne Aquifer (BA) and Upper Floridan Aquifer (UFA) in south Florida. The most significant differences between the BA (26 meters below surface) and UFA (366 meters below surface) are the average specific conductance (0.552 and 6.12 microsiemens per centimeter, respectively), dissolved oxygen (1.6 and 0 milligrams per liter, respectively), and oxidation-reduction potential (40.3 and -358 millivolts, respectively). The dissolved organic carbon from the BA is characterized by carbon originating from terrestrial sources and microbial activities, while the UFA has a distinctive microbial signature. Acetate and lactate are the dominant carbon constituents in both aquifers. Additionally, components of the dissolved organic carbon from the UFA have a total trihalomethane-formation potential that is approximately threefold greater than the maximum contaminat level of 80 micrograms per liter established by the U.S. Environmental Protection Agency. The average native bacterial abundances in the aquifers are similar with 4.69x10^4 cells per milliliter in the BA and 1.33x10^4 cells per milliliter in the UFA. The average bacteriophage abundances are also similar with 1.15x10^5 virus-like particles in the BA and 1.92x10^5 virus-like particles in the UFA. Interestingly, ciliated protozoa are present in both aquifers. The average abundance of ciliates in the BA (2.97x10^3 ciliates per milliliter) is approximately twentyfold greater than abundances in the UFA (1.39x10^2 ciliates per milliliter). Collectively, these data indicate that microbial processes are the dominant contributor to the cycling of carbon and inorganic carbon in the BA and may be the only carbon cycling process in the UFA, as this aquifer has not had a terrestrial influx of carbon for more than 15,000 years. The rates of carbon, in the form of acetate, utilization by the native microbial communities are significantly different between the two aquifers. Based on data from 14C-acetate-utilization experiments, the microbial communities in the BA turn over the native acetate in 2.5 years, whereas communities in the UFA turn over native acetate in 6.8 years. These data support the hypothesis derived from the microbial-abundance data, in that the carbon for bacterial maintainence and growth is recycled from bacterial biomass released during cell lysis, especially in the UFA. An in situ diffusion chamber was designed to retain bacterial cells within the chamber while allowing native water constituents to move through the chamber. A series of 1-week deployments of chambers filled with fluorescent beads, inactivated native bacteria and laboratory grown and viable bacteria into the UFA, permitted by the State of Florida Environmental Protection Agency, was successfully completed. This was the first time this type of deployment into an aquifer system that is used for potable water supply has been permitted within the United States. This technology will allow, for the first time, in situ studies on the survival of microbial indicators of fecal pollution and true pathogens in groundwater systems.

Florida↗

USGS2013

Differential expression profiles of microRNA in the little brown bat (Myotis lucifugus) associated with white nose syndrome affected and unaffected individuals

First documented in New York State in 2006, white nose syndrome (WNS) quickly became the leading cause of mortality in hibernating bat species in the United States. WNS is caused by a psychrophilic fungus, Geomyces destructans. Clinical signs of this pathogen are expressed as a dusty white fungus predominately around the nose and on the wings of affected bats. Relatively new biomarkers, such as microRNAs (miRNAs) are being targeted as markers to predict the syndrome prior to the clinical manifestation. The primary objective of this study was to identify miRNAs that could serve as biomarkers and proxies of little brown bat health. Bats were collected from hibernacula that had tested positive and negative for WNS. Genetic sequencing was completed using the Ion Torrent platform. A number of miRNAs were identified from the liver as putative biomarkers of WNS. However, given the small sample size for each treatment, this data set has only coarsely identified miRNAs indicative of WNS, and further validation is required.

Open-File Report↗

USGS2015

Strategy to evaluate persistent contaminant hazards resulting from sea-level rise and storm-derived disturbances—Study design and methodology for station prioritization

Coastal communities are uniquely vulnerable to sea-level rise (SLR) and severe storms such as hurricanes. These events enhance the dispersion and concentration of natural and anthropogenic chemicals and pathogenic microorganisms that could adversely affect the health and resilience of coastal communities and ecosystems in coming years. The U.S. Geological Survey has developed a strategy to define baseline and post-event sediment-bound environmental health (EH) stressors (hereafter referred to as the Sediment-Bound Contaminant Resiliency and Response [SCoRR] strategy). A tiered, multimetric approach will be used to (1) identify and map contaminant sources and potential exposure pathways for human and ecological receptors, (2) define the baseline mixtures of EH stressors present in sediments and correlations of relevance, (3) document post-event changes in EH stressors present in sediments, and (4) establish and apply metrics to quantify changes in coastal resilience associated with sediment-bound contaminants. Integration of this information provides a means to improve assessment of the baseline status of a complex system and the significance of changes in contaminant hazards due to storm-induced (episodic) and SLR (incremental) disturbances. This report describes the purpose and design of the SCoRR strategy and the methods used to construct a decision support tool to identify candidate sampling stations vulnerable to contaminants that may be mobilized by coastal storms.

Connecticut, Delaware, District of Columbia, Maine↗

USGS2015

Standard operating procedures for collection of soil and sediment samples for the Sediment-bound Contaminant Resiliency and Response (SCoRR) strategy pilot study

An understanding of the effects on human and ecological health brought by major coastal storms or flooding events is typically limited because of a lack of regionally consistent baseline and trends data in locations proximal to potential contaminant sources and mitigation activities, sensitive ecosystems, and recreational facilities where exposures are probable. In an attempt to close this gap, the U.S. Geological Survey (USGS) has implemented the Sediment-bound Contaminant Resiliency and Response (SCoRR) strategy pilot study to collect regional sediment-quality data prior to and in response to future coastal storms. The standard operating procedure (SOP) detailed in this document serves as the sample-collection protocol for the SCoRR strategy by providing step-by-step instructions for site preparation, sample collection and processing, and shipping of soil and surficial sediment (for example, bed sediment, marsh sediment, or beach material). The objectives of the SCoRR strategy pilot study are (1) to create a baseline of soil-, sand-, marsh sediment-, and bed-sediment-quality data from sites located in the coastal counties from Maine to Virginia based on their potential risk of being contaminated in the event of a major coastal storm or flooding (defined as Resiliency mode); and (2) respond to major coastal storms and flooding by reoccupying select baseline sites and sampling within days of the event (defined as Response mode). For both modes, samples are collected in a consistent manner to minimize bias and maximize quality control by ensuring that all sampling personnel across the region collect, document, and process soil and sediment samples following the procedures outlined in this SOP. Samples are analyzed using four USGS-developed screening methods—inorganic geochemistry, organic geochemistry, pathogens, and biological assays—which are also outlined in this SOP. Because the SCoRR strategy employs a multi-metric approach for sample analyses, this protocol expands upon and reconciles differences in the sample collection protocols outlined in the USGS “National Field Manual for the Collection of Water-Quality Data,” which should be used in conjunction with this SOP. A new data entry and sample tracking system also is presented to ensure all relevant data and metadata are gathered at the sample locations and in the laboratories.

Open-File Report↗

USGS2015

Air- and stream-water-temperature trends in the Chesapeake Bay region, 1960-2014

Water temperature is a basic, but important, measure of the condition of all aquatic environments, including the flowing waters in the streams that drain our landscape and the receiving waters of those streams. Climatic conditions have a strong influence on water temperature, which is therefore naturally variable both in time and across the landscape. Changes to natural water-temperature regimes, however, can result in a myriad of effects on aquatic organisms, water quality, circulation patterns, recreation, industry, and utility operations. For example, most species of fish, insects, and other organisms, as well as aquatic vegetation, are highly dependent on water temperature. Warming waters can result in shifts in floral and faunal species distributions, including invasive species and pathogens previously unable to inhabit the once cooler streams. Many chemical processes are temperature dependent, with reactions occurring faster in warmer conditions, leading to degraded water quality as contaminants are released into waterways at greater rates. Circulation patterns in receiving waters, such as bays and estuaries, can change as a result of warmer inflows from streams, thereby affecting organisms in those receiving waters. Changes in abundance of some aquatic species and (or) degradation of water quality can reduce the recreational value of water bodies as waters are perceived as less desirable for water-related activities or as sportfish become less available for anglers. Finally, increasing water temperatures can affect industry and utilities as the thermal capacity is reduced, making the water less effective for cooling purposes. Chesapeake Bay is the largest estuary in the United States. Eutrophication, the enrichment of a water body with excess nutrients, has plagued the bay for decades and has led to extensive restoration efforts throughout the bay watershed. The warming of stream water can exacerbate eutrophication through increased release of nutrients from in-stream sediments, so understanding changes in stream-water temperature throughout the bay watershed is critical to resource managers seeking to restore the bay ecosystem. The U.S. Environmental Protection Agency (EPA) uses indicators that “represent the state or trend of certain environmental or societal conditions … to track and better understand the effects of changes in the Earth’s climate” (U.S. Environmental Protection Agency, 2014). Updates to these indicators are published biennially by the EPA. The U.S. Geological Survey (USGS), in cooperation with the EPA, has completed analyses of air- and stream-water-temperature trends in the Chesapeake Bay region to be included as an indicator in a future release of the EPA report.

Delaware, Maryland, New York, Pennsylvania, Virgin↗

USGS2016

Relation between Enterococcus concentrations and turbidity in fresh and saline recreational waters, coastal Horry County, South Carolina, 2003–04

Bacteria related to the intestinal tract of humans and other warm-blooded animals have been detected in fresh and saline surface waters used for recreational purposes in coastal areas of Horry County, South Carolina, since the early 2000s. Specifically, concentrations of the facultative anaerobic organism, Enterococcus , have been observed to exceed the single-sample regulatory limit of 104 colony forming units per 100 milliliters of water. Water bodies characterized by these concentrations are identified on the 303(d) list for impaired water in South Carolina; moreover, because current analytical methods used to monitor Enterococcus concentrations take up to 1 day for results to become available, water-quality advisories are not reflective of the actual health risk. To determine if Enterococcus concentrations in surface water could be assessed in a more rapid manner, an investigation was completed between 2003 and 2004 in the study area of coastal Horry County, South Carolina. The study was designed to assess the relation between Enterococcus concentrations and turbidity, which, unlike Enterococcus concentrations, can be measured continuously by using a multiparameter water-quality sensor and results reported in real time. In 2003, three water-quality data collection stations that included a multiparameter water-quality sensor that measured turbidity were located in three representative surface-water basins in coastal Horry County, South Carolina. All these locations had previous reports of high Enterococcus concentrations. At each station, the water-quality sensor was placed in the water column and continuously measured turbidity, pH, specific conductivity, dissolved oxygen, and temperature. Each water-quality data collection station also monitored instantaneous precipitation and wind speed and direction. Surface-water samples were collected at each station during events characterized by no precipitation and by some recorded precipitation using manual and automatic methods, and analyzed for Enterococcus concentrations. A comparison of Enterococcus concentrations in surface-water samples collected simultaneously using both methods indicated a positive relation, although the average percent relative difference between the methods was 46 percent. During a period of no precipitation in February 2004, no relation between turbidity and Enterococcus concentrations was observed for surface-water samples collected at the water-quality data collection station located in the channel that drains a freshwater swamp. In contrast, during periods of precipitation in March and August 2004 at this location, a positive relation was observed between turbidity and Enterococcus concentrations in surface-water samples; that is, water samples characterized by higher turbidity also contained higher Enterococcus concentrations. At the water-quality data collection station located in a channel that drains to the surf zone of the Atlantic Ocean, no relation was observed between turbidity and Enterococcus concentrations during periods of either no precipitation (July 2004) or precipitation (August 2004). At this location, the turbidity was inversely related to relative tide height, high turbidity was observed during low tide when freshwater flowed seaward, and low turbidity was observed during high tide when saline seawater flowed landward. The positive relation observed between turbidity and Enterococcus concentrations in surface water at the water-quality data collection station located in the channel that drains a freshwater swamp may be attributed to bacterial survival in the abundant channel bed sediments that characterized this more naturalized area. Surface-water bed sediments collected near each water-quality data collection station and the surf zone were incubated in static microcosms in the laboratory and analyzed for Enterococcus concentrations over time. Enterococcus concentrations continued to persist in bed sediments collected in the channel that drains the swamp even after almost 4 months of incubation. Conversely, enterococci were not observed to persist in bed sediments characterized by high specific conductance. Although it is currently (2016) unknown whether this persistence of enterococci demonstrates growth or viability, the data indicate that enterococci can exist in channel bed-sediment environments outside of a host for a long time. This observation confirms previous reports that challenge the use of Enterococcus concentrations as an indicator of the recent introduction of fecal-related material and the associated acute risk to other pathogens.

South Carolina↗

USGS2018

Methods used for the collection and analysis of chemical and biological data for the Tapwater Exposure Study, United States, 2016–17

In 2016, the U.S. Geological Survey (USGS) Environmental Health Mission Area, initiated the Tapwater Exposure Study as part of an infrastructure project to assess human exposure to potential threats from complex mixtures of contaminants. In the pilot phase (2016), samples were collected from 11 States throughout the United States, and in the second phase (2017), the study focused on the Greater Chicago area, including North and South Chicago, Illinois, and East Chicago, Indiana. Residential tapwater samples were collected at private residences during both phases, and during the first phase, samples were collected from Federal office buildings and from one office 19-liter water-bottle source. During the second phase, raw intake and treated (pre-distributional) water samples also were collected from four drinking-water treatment facilities in the Greater Chicago area. Samples were sent to laboratories at the USGS, U.S. Environmental Protection Agency, National Institute of Environmental Health Sciences, and Colorado School of Mines Center for Environmental Risk Assessment, for potential drinking-water pathogens, chemical, and bioassay analyses. These analyses included more than 400 chemicals such as trace elements, steroid hormones, pharmaceuticals, volatile organic compounds, pesticides, per- and polyfluorinated alkyl substances, cyanotoxins, and other organic compounds. The in vitro bioassay analyses included estrogen, androgen, and glucocorticoid receptor activity.

Open-File Report↗

USGS2018

Batrachochytrium salamandriovrans (Bsal) in Appalachia—Using scenario building to proactively prepare for a wildlife disease outbreak caused by an invasive amphibian chytrid fungus

Batrachochytrium salamandrivorans ( Bsal ), a pathogenic chytrid fungus, is nonnative to the United States and poses a disease threat to vulnerable amphibian hosts. The Bsal fungus may lead to increases in threatened, endangered, and sensitive status listings at State, Tribal, and Federal levels, resulting in financial costs associated with implementing the Endangered Species Act of 1973. The United States is a global biodiversity hotspot for salamanders, an order of amphibians that is particularly vulnerable to developing a disease called chytridiomycosis when exposed to Bsal . Published Bsal risk assessments for North America have suggested that salamanders within the Appalachian region of the United States are at a high risk. In May 2017, a workshop was facilitated by the Department of the Interior’s Strategic Sciences Group. During the workshop, a discussion-based incident-response exercise focused on a hypothetical Bsal disease outbreak in Appalachia was led by U.S. Geological Survey staff members. Participants included representatives of the Eastern Band of the Cherokee Indians, U.S. Fish and Wildlife Service, National Park Service, Appalachian Landscape Conservation Cooperative, Tennessee Wildlife Resources Agency, and U.S. Department of Agriculture’s U.S. Forest Service. Scenario building was used to brainstorm cascading consequences (social, economic, and ecological) of a Bsal disease outbreak in the Appalachian region. This report highlights the management and science actions that could be undertaken to ensure an effective, rapid response to a Bsal introduction into the United States.

Open-File Report↗

USGS2019

An experimental test of weed-suppressive bacteria effectiveness in rangelands in southwestern Idaho, 2016–18

Approaches and techniques for control of exotic annual grasses are a high priority in sagebrush-steppe and other rangelands. Strains of the soil bacterium Pseudomonas fluorescens (Pf) have been proposed to be selectively pathogenic to multiple species of exotic annual grasses with effects evident by the second year, and with no effect on native or desirable species including native bunchgrasses. However, scientifically defensible tests of the target and non-target/risk effects of these hypothetically weed-suppressive bacteria (WSB) strains in the field have been lacking in rangelands and other environments. We evaluated the effects of two strains of Pf WSB (D7 and MB906) sprayed on the surface in autumn 2016 at three sites in sagebrush steppe across southwestern Idaho that had cheatgrass ( Bromus tectorum ), medusahead ( Taeniatherum caput-medusae ), and other exotic annual grasses. Treatments also were replicated within each site (n=3, 8.3×8.3 meter plots) and included evaluation of the WSB strains with and without herbicides (imazapic and rimsulfuron) and with or without discing to mix surface-spray of the WSB into deeper soils. By the second year following application (spring 2018), neither strain of WSB affected exotic annual grasses, perennial bunchgrasses, or total community cover, either with WSB alone or in combination with herbicides or discing. We conclude that neither the D7 nor MB906 strains of Pf WSB have a negative effect on exotic annuals at the sites we evaluated.

Idaho↗

USGS2024

Summary of data collected during field efficacy trials of florfenicol and oxytetracycline dihydrate in controlling mortality in walleye (Sander vitreus) because of motile Aeromonad infections

Motile Aeromonad septicemia is a substantial concern during fish propagation and can be catastrophic for fish hatcheries. We tested the efficacy of two different drugs (florfenicol and oxytetracycline) offered with feed as possible treatment options to control mortality because of motile Aeromonad infection. We offered top-coated medicated feeds to hatchery-reared Sander vitreus (walleye) that were naturally infected with motile Aeromonad infection during two separate trials in 2011 and 2012. Substantial walleye mortality occurred before positive clinical outcomes from the medicated feed treatments were observed, and additional treatment measures were taken by hatchery staff to mitigate further mortality in their walleye production tanks. This report summarizes the data that were collected during medicated feed trials. Statistical inferences on treatment efficacy are not included because of the confounding treatments and possible secondary pathogens present throughout this study.

Open-File Report↗