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USGS2016

Ungulate reproductive parameters track satellite observations of plant phenology across latitude and climatological regimes

The effect of climatically-driven plant phenology on mammalian reproduction is one key to predicting species-specific demographic responses to climate change. Large ungulates face their greatest energetic demands from the later stages of pregnancy through weaning, and so in seasonal environments parturition dates should match periods of high primary productivity. Interannual variation in weather influences the quality and timing of forage availability, which can influence neonatal survival. Here, we evaluated macro-scale patterns in reproductive performance of a widely distributed ungulate (mule deer, Odocoileus hemionus ) across contrasting climatological regimes using satellite-derived indices of primary productivity and plant phenology over eight degrees of latitude (890 km) in the American Southwest. The dataset comprised > 180,000 animal observations taken from 54 populations over eight years (2004–2011). Regionally, both the start and peak of growing season (“Start” and “Peak”, respectively) are negatively and significantly correlated with latitude, an unusual pattern stemming from a change in the dominance of spring snowmelt in the north to the influence of the North American Monsoon in the south. Corresponding to the timing and variation in both the Start and Peak, mule deer reproduction was latest, lowest, and most variable at lower latitudes where plant phenology is timed to the onset of monsoonal moisture. Parturition dates closely tracked the growing season across space, lagging behind the Start and preceding the Peak by 27 and 23 days, respectively. Mean juvenile production increased, and variation decreased, with increasing latitude. Temporally, juvenile production was best predicted by primary productivity during summer, which encompassed late pregnancy, parturition, and early lactation. Our findings offer a parsimonious explanation of two key reproductive parameters in ungulate demography, timing of parturition and mean annual production, across latitude and changing climatological regimes. Practically, this demonstrates the potential for broad-scale modeling of couplings between climate, plant phenology, and animal populations using space-borne observations.

Arizona, Colorado, Utah↗

USGS1990

National Coastal Geology Program: a plan of geologic research on coastal erosion, coastal wetlands, polluted sediments, and coastal hard-mineral resources

More than 50 percent of the U.S. population currently live within 50 miles of an ocean, Great Lake, or major estuary. According to forecasts, the concentration of people along our coastlines will continue to increase into the 21st century. In addition to residential and commercial buildings and facilities worth tens of billions of dollars, the coasts and associated wetlands are natural resources of tremendous value, with estimates in excess of $13 billion per year for commercial and recreational fisheries alone. Human activities and natural processes are stressing the coastal environment. * Each of the coastal states and island territories is suffering problems related to coastal erosion. * Deterioration of wetlands is widespread and of great public concern. * Pollutants carried by rivers or runoff are discharged directly into coastal waters and accumulate in the sediments on the sea floor, in some areas causing damage to living resources and presenting a threat to public health. * Onshore sources for hard-mineral resources, such as sand and gravel used for construction purposes, are becoming increasingly difficult to find. New sources are being sought in coastal waters. Coastal issues will become even more important into the next century if sea level is significantly influenced by climate change and other factors.

Monograph↗

USGS2002

Preliminary hydrogeologic assessment and study plan for a regional ground-water resource investigation of the Blue Ridge and Piedmont provinces of North Carolina

Prolonged drought, allocation of surface-water flow, and increased demands on ground-water supplies resulting from population growth are focuses for the need to evaluate ground-water resources in the Blue Ridge and Piedmont Provinces of North Carolina. Urbanization and certain aspects of agricultural production also have caused increased concerns about protecting the quality of ground water in this region. More than 75 percent of the State's population resides in the Blue Ridge and Piedmont Provinces in an area that covers 30,544 square miles and 65 counties. Between 1940 and 2000, the population in the Piedmont and Blue Ridge Provinces increased from 2.66 to 6.11 million; most of this increase occurred in the Piedmont. Of the total population, an estimated 1.97 million people, or 32.3 percent (based on the 1990 census), relied on ground water for a variety of uses, including commercial, industrial, and most importantly, potable supplies. Ground water in the Blue Ridge and Piedmont traditionally has not been considered as a source for large supplies, primarily because of readily available and seemingly limitless surface-water supplies, and the perception that ground water in the Blue Ridge and Piedmont Provinces occurs in a complex, generally heterogeneous geologic environment. Some reluctance to use ground water for large supplies derives from the reputation of aquifers in these provinces for producing low yields to wells, and the few high-yield wells that are drilled seem to be scattered in areas distant from where they are needed. Because the aquifers in these provinces are shallow, they also are susceptible to contamination by activities on the land surface. In response to these issues, the North Carolina Legislature supported the creation of a Resource Evaluation Program to ensure the long-term availability, sustainability, and quality of ground water in the State. As part of the Resource Evaluation Program, the North Carolina Division of Water Quality, Groundwater Section, in cooperation with the U.S. Geological Survey, initiated a multiyear study of ground water in the Blue Ridge and Piedmont Provinces. The study began in 1999. Most of the study area is underlain by a complex, two-part, regolith-fractured crystalline rock aquifer system. Thickness of the regolith throughout the study area is highly variable and ranges from 0 to more than 150 feet. The regolith consists of an unconsolidated or semiconsolidated mixture of clay and fragmental material ranging in grain size from silt to boulders. Because porosities range from 35 to 55 percent, the regolith provides the bulk of the water storage within the Blue Ridge and Piedmont ground-water system. At the base of the regolith is the transition zone where saprolite grades into unweathered bedrock. The transition zone has been identified as a potential conduit for rapid ground-water flow. If this is the case, the transition zone also may serve as a conduit for rapid movement of contaminants to nearby wells or to streams with channels that cut into 1 U.S. Geological Survey, Raleigh, North Carolina. 2 North Carolina Department of Environment and Natural Resources, Division of Water Quality, Groundwater Section. or through the transition zone. How rapidly a contaminant moves through the system largely may be a function of the characteristics of the transition zone. The transition zone is one of several topics identified during the literature review and data synthesis, for which there is a deficiency in data and understanding of the processes involved in the movement of ground water to surface water. Because the Blue Ridge and Piedmont study area is so large, and the hydrogeology diverse, it is not feasible to study all of the area in detail. A more feasible approach is to select areas that are most representative of the land use, geology, and hydrology to obtain an understanding of the hydrologic processes in the selected areas, and transfer the knowledge from these local "type areas" to similar regional hydrogeologic areas. For the purpose of this study, the term "type area" applies to a 10- to 100-square mile area within a hydrogeologic terrane where information is sufficient to develop and test a concept of ground-water flow by using analytical or numerical methods that can be validated by field measurements. Ideally, these type areas are selected to be representative of the flow system that is present wherever a particular hydrogeologic terrane is present. This report consists of two basic parts. The first part describes the results of a comprehensive review and synthesis of information and literature that provides the basic background for the study. This includes current (2002) knowledge regarding general geology and the hydrogeologic framework of the fractured-rock aquifer system that underlies the Blue Ridge and Piedmont Provinces. In spite of the quantity of information identified during the literature review and the amount of past work that has been documented, there are still research needs to be met. The second part of the report describes State ground-water issues and problems, available data, and data deficiencies. It also describes the design and implementation of efforts to characterize ground-water quality and to quantify factors that influence the movement and availability of ground water in the hydrogeologic terranes characterized by (1) massive or foliated crystalline rocks overlain by thick regolith and (2) massive or foliated crystalline rocks overlain by thin regolith. As of September 2001, seven sites had been identified as potential study sites to be used to characterize the hydrogeology and water quality of ype areas considered representative of the larger terranes. Detailed geologic mapping, core drilling, well installation, and surface and borehole geophysical surveys are in progress at four of the sites.

North Carolina↗

USGS2022

An integrated approach for physical, economic, and demographic evaluation of coastal flood hazard adaptation in Santa Monica Bay, California

The increased risk of coastal flooding associated with climate-change driven sea level rise threatens to displace communities and cause substantial damage to infrastructure. Site-specific adaptation planning is necessary to mitigate the negative impacts of flooding on coastal residents and the built environment. Cost-benefit analyses used to evaluate coastal adaption strategies have traditionally focused on economic considerations, often overlooking potential demographic impacts that can directly influence vulnerability in coastal communities. Here, we present a transferable framework that couples hydrodynamic modeling of flooding driven by sea level rise and storm scenarios with site-specific building stock and census block-level demographic data. We assess the efficacy of multiple coastal adaptation strategies at reducing flooding, economic damages, and impacts to the local population. We apply this framework to evaluate a range of engineered, nature-based, and hybrid adaptation strategies for a portion of Santa Monica Bay, California. Overall, we find that dual approaches that provide protection along beaches using dunes or seawalls and along inlets using sluice gates perform best at reducing or eliminating flooding, damages, and population impacts. Adaptation strategies that include a sluice gate and partial or no protection along the beach are effective at reducing flooding around inlets but can exacerbate flooding elsewhere, leading to unintended impacts on residents. Our results also indicate trade-offs between economic and social risk-reduction priorities. The proposed framework allows for a comprehensive evaluation of coastal protection strategies across multiple objectives. Understanding how coastal adaptation strategies affect hydrodynamic, economic, and social factors at a local scale can enable more effective and equitable planning approaches.

California↗

USGS2023

Parallel shifts in trout feeding morphology suggest rapid adaptation to alpine lake environments

Eco-evolutionary interactions following ecosystem change provide critical insight into the ability of organisms to adapt to shifting resource landscapes. Here we explore evidence for the rapid parallel evolution of trout feeding morphology following eco-evolutionary interactions with zooplankton in alpine lakes stocked at different points in time in the Wind River Range (Wyoming, USA). In this system, trout predation has altered the zooplankton species community and driven a decrease in average zooplankton size. In some lakes that were stocked decades ago, we find shifts in gill raker traits consistent with the hypothesis that trout have rapidly adapted to exploit available smaller-bodied zooplankton more effectively. We explore this morphological response in multiple lake populations across two species of trout (cutthroat trout, Oncorhynchus clarkii , and golden trout Oncorhynchus aguabonita ) and examine the impact of resource availability on morphological variation in gill raker number among lakes. Furthermore, we present genetic data to provide evidence that historically stocked cutthroat trout populations likely derive from multiple population sources, and incorporate variation from genomic relatedness in our exploration of environmental predictors of feeding morphology. These findings describe rapid adaptation and eco-evolutionary interactions in trout and document an evolutionary response to novel, contemporary ecosystem change.

Evolution↗

USGS2012

Differences in survival and growth in hatchery and stream environments, and in maturation of residuls in a stream, between progeny of hatchery and wild steelhead (Study sites: Brushy Fork Creek and Dworshak Hatchery; Stocks:Dworshak hatchery and Fish Creek wild; Year classes: 1992 and 1993)

Freshwater survival in hatchery and natural rearing environments was compared between progeny of hatchery (H) and wild (W) steelhead Oncorhynchus mykiss from the Clearwater River drainage in Idaho. Adults from Dworshak National Fish Hatchery and wild adults from Fish Creek fish were artificially spawned, and their progeny were genetically marked at the PEPA allozyme locus and released together as unfed fry in production facilities at the hatchery and in Brushy Fork Creek, also in the Clearwater River drainage, in a common garden design. Survival was higher for H than for W progeny at the hatchery but lower for H than for W progeny in Brushy Fork, indicating reduced fitness of the hatchery population for natural rearing and suggesting domestication as the cause. Survival at the hatchery was lower than is typical due to disease outbreaks. Survival of the first year-class of experimental fish to smolt release was only 18%. Survival of H fish was 3.8 times that of W fish under these poor survival conditions. All fish from the second year-class died halfway through the scheduled 10 month rearing period. Survival of H fish was 5.2 times that of W fish to when 1% of the initial fry were still alive indicating that W fish succumbed to the epizootic sooner than did H fish. Emigrants from the Brushy Fork study reach were sampled for three years and fish residing in the study reach were sampled for six years following fry release. Most emigrants were one or two years old and too small to be smolts (mean fork length at age-2 = 93 mm). Survival in Brushy Fork was lower for H than for W fish of the first year-class. Survival of the second year-class was higher for H than for W fish during the first two months in the stream but was lower for H than for W fish thereafter, and net survival from release to ages 3 and older was also lower for H than for W fish if our emigrant samples were representative (periods of inoperative emigrant traps prevented certainty about this). Differences between progeny groups were also found for growth (H>W) and condition (H>W) in the hatchery and downstream migration success of hatchery-reared fish after release (H>W), and for growth (H<W for one year-class; H>W for the other), condition (H>W), downstream dispersal (H>W for one year-class; H=W for the other), and maturation of residuals (ovaries weight was greater for H than for W females at ages 4 and 5; testes weight was less for H than for W age-3 males of one year-class) in Brushy Fork. A thunderstorm-induced power outage interrupted flow to the incubation trays at the hatchery and compromised a major tenet of the common garden design for the second year-class, possibly contributing to the inconsistency in relative survivals in Brushy Fork between year-classes. The storm caused the incubation environment to differ between the stocks as a result of reduced oxygen levels and substantially higher densities for H alevins. This difference was illustrated by a 55% loss for H fish during the event, about twice that for W fish.

Idaho↗

USGS2020

Gambel’s quail survey variability and implications for survey design in the Mohave Desert

Careful design of a wildlife population monitoring strategy is necessary to obtain accurate and precise results whether the purpose of the survey is development of habitat suitability models, to estimate abundance, or assess site occupancy. Important characteristics to consider in survey design are sources of elevated variability, particularly within‐subject variability, which increases the amount of data needed to achieve statistical certainty either in terms of population trend analysis, hypothesis testing, or statistical power. However, alternative objectives, such as associating counts with habitat characteristics, may benefit from increased variation among counts when differences covary with habitat measures. This difference can result in competing needs when developing survey protocols. We investigated the relative precision of differing gamebird monitoring protocols to identify methods with the greatest statistical efficiency. We assessed call‐count transects using standard Breeding Bird Survey protocols (Passive call‐counts) and modified by including longer survey periods and call playback (Active call‐counts), autonomous recording units with supervised call detection (ARU‐recorded calls), camera traps, and roadside covey‐counts for Gambel's quail ( Callipepla gambelii ) in the Mojave Desert (CA, USA) during the spring of 2016. Active call‐counts had the lowest within‐site variation relative to estimated population index values, but Passive call‐count transects may be more efficient for some purposes because more survey stations can be completed within a single survey timeframe. The ARU‐recorded calls may provide a suitable alternative despite larger sample size needs, especially for occupancy surveys because multiple units can be deployed concurrently. The ultimate sample size required will depend on specific study objectives and scope of interest, but camera traps and breeding‐season covey counts are not likely to meet objectives in desert environments.

California↗

USGS2014

The geochemistry of deep-sea coral skeletons: a review of vital effects and applications for palaeoceanography

Deep-sea corals were discovered over a century ago, but it is only over recent years that focused efforts have been made to explore the history of the oceans using the geochemistry of their skeletal remains. They offer a promising archive of past oceanic environments given their global distribution, layered growth patterns, longevity and preservation as well as our ability to date them using radiometric techniques. This paper provides an overview of the current state-of-the-art in terms of geochemical approaches to using deep-sea coral skeletons to explore the history of the ocean. Deep-sea coral skeletons have a wide array of morphologies (e.g. solitary cup corals, branching colonial corals) and materials (calcite, aragonite and proteins). As such their biomineralization strategies are diverse, leading to complex geochemistry within coral skeletons. Notwithstanding these complications, progress has been made on developing methods for reconstructing the oceanographic environment in the past using trace elements and isotopic methods. Promising approaches within certain coral groups include clumped isotopes and Mg/Li for temperature reconstructions, boron isotopes and radiocarbon for carbon cycling, εNd, and radiocarbon for circulation studies and δ 15 N, P/Ca and Ba/Ca for nutrient tracer studies. Likewise there is now a range of techniques for dating deep-sea corals skeletons (e.g. U-series, radiocarbon), and determining their growth rates (e.g. radiocarbon and 210 Pb). Dating studies on historic coral populations in the Atlantic, Southern Ocean and Pacific point to climate and environmental changes being dominant controls on coral populations over millennial and orbital timescales. This paper provides a review of a range of successes and promising approaches. It also highlights areas in which further research would likely provide new insights into biomineralization, palaeoceanography and distribution of past coral populations.

Deep-Sea Research Part II: Topical Studies in Ocea↗

USGS2019

Consistent compensatory growth offsets poor condition in trout populations

1. Compensatory growth – when individuals in poor condition grow rapidly to “catch up” to conspecifics – may be a mechanism that allows individuals to tolerate stressful environmental conditions, both abiotic and biotic. This phenomenon has been documented fairly widely in laboratory and field experiments, but evidence for compensatory growth in the wild is scarce. 2. Cutthroat trout (Oncorhynchus clarkii subsp) are cold-water specialists that inhabit streams in montane ecosystems where seasonal conditions can be harsh and growth rates vary greatly among seasons. Understanding if individuals compensate for periods of reduced growth and body condition will improve understanding of the requirements of fish throughout their life-cycle and across freshwater habitats. 3. We quantified compensatory growth of juvenile cutthroat trout using extensive mark-recapture data from 11 stream populations (1,125 individuals) and two subspecies inhabiting a wide range of ecological settings in the northern Rocky Mountains, USA. Our objectives were to determine how growth was linked across seasons and determine if individuals behaviorally compensated for depressed body condition via emigration. 4. Fish in relatively poor condition consistently demonstrated compensatory growth in mass during subsequent seasons. In contrast, fish in relatively better condition responded with positive growth in length during the summer signaling these fish may be better suited to headwater environments; no compensatory growth in length was found during the winter. Furthermore, we found no evidence that individual condition mediated migration tendencies of fish to seek more favorable habitat. 5. Across a wide range of environmental conditions, we found consistent empirical support for compensatory growth in mass in the wild. A critical next step is to quantify how changing abiotic and biotic conditions influence the ability of stream fishes to compensate for locally or seasonally challenging conditions, thereby affecting long-term resiliency, viability, and adaptation in the face of changing environmental conditions.

Montana, Wyoming↗

USGS2020

Insects in high-elevation streams: Life in extreme environments imperiled by climate change

Climate change is altering conditions in high-elevation streams worldwide, with largely unknown effects on resident communities of aquatic insects. Here, we review the challenges of climate change for high-elevation aquatic insects and how they may respond, focusing on current gaps in knowledge. Understanding current effects and predicting future impacts will depend on progress in three areas. First, we need better descriptions of the multivariate physical challenges and interactions among challenges in high-elevation streams, which include low but rising temperatures, low oxygen supply and increasing oxygen demand, high and rising exposure to ultraviolet radiation, low ionic strength, and variable but shifting flow regimes. These factors are often studied in isolation even though they covary in nature and interact in space and time. Second, we need a better mechanistic understanding of how physical conditions in streams drive the performance of individual insects. Environment-performance links are mediated by physiology and behavior, which are poorly known in high-elevation taxa. Third, we need to define the scope and importance of potential responses across levels of biological organization. Short-term responses are defined by the tolerances of individuals, their capacities to perform adequately across a range of conditions, and behaviors used to exploit local, fine-scale variation in abiotic factors. Longer term responses to climate change, however, may include individual plasticity and evolution of populations. Whether high-elevation aquatic insects can mitigate climatic risks via these pathways is largely unknown.

Global Change Biology↗

USGS1960

The trumpeter swan: its history, habits, and population in the U.S

This report on the trumpeter evolved from studies made from 1948 to 1957 when I served first as an assistant and later as manager, of the Red Rock Lakes Refuge. I have also drawn extensively on the records of the National Park Service, the U. S. Fish and Wildlife Service, and the National Museum in Washington, D. C. Other pertinent information bearing on the life history of the trumpeter swan in the United States has been extracted from published articles, unpublished reports and records, firsthand accounts and correspondence. This account includes a historical record of this bird in the United States and Alaska, an outline of its habits and characteristics in its native Rocky Mountain environment, and furnishes information necessary to guide its future.

North American Fauna↗

USGS2003

Estimates of global cyanobacterial biomass and its distribution

We estimated global cyanobacterial biomass in the main reservoirs of cyanobacteria on Earth: marine and freshwater plankton, arid land soil crusts, and endoliths. Estimates were based on typical population density values as measured during our research, or as obtained from literature surveys, which were then coupled with data on global geographical area coverage. Among the marine plankton, the global biomass of Prochlorococcus reaches 120 × 10 12 grams of carbon (g C), and that of Synechoccus some 43 × 10 12 g C. This makes Prochlorococcus and Synechococcus , in that order, the most abundant cyanobacteria on Earth. Tropical marine blooms of Trichodesmium account for an additional 10 × 10 12 g C worldwide. In terrestrial environments, the mass of cyanobacteria in arid land soil crusts is estimated to reach 54 × 10 12 g C and that of arid land endolithic communities an additional 14 × 10 12 g C. The global biomass of planktic cyanobacteria in lakes is estimated to be around 3 × 10 12 g C. Our conservative estimates, which did not include some potentially significant biomass reservoirs such as polar and subarctic areas, topsoils in subhumid climates, and shallow marine and freshwater benthos, indicate that the total global cyanobacterial biomass is in the order of 3 × 10 14 g C, surpassing a thousand million metric tons (10 15 g) of wet biomass.

Algological Studies↗

USGS2007

Geoinformatics 2007: data to knowledge

Geoinformatics is the term used to describe a variety of efforts to promote collaboration between the computer sciences and the geosciences to solve complex scientific questions. It refers to the distributed, integrated digital information system and working environment that provides innovative means for the study of the Earth systems, as well as other planets, through use of advanced information technologies. Geoinformatics activities range from major research and development efforts creating new technologies to provide high-quality, sustained production-level services for data discovery, integration and analysis, to small, discipline-specific efforts that develop earth science data collections and data analysis tools serving the needs of individual communities. The ultimate vision of Geoinformatics is a highly interconnected data system populated with high quality, freely available data, as well as, a robust set of software for analysis, visualization, and modeling.

Scientific Investigations Report↗

USGS2008

Geoinformatics 2008 - Data to Knowledge

Scientific Investigations Report↗

USGS2022

Golden eagle occupancy surveys and monitoring strategy in coastal southern California, United States

Golden eagles ( Aquila chrysaetos ) are of increasing conservation concern in western North America. Effective conservation measures for this wide-ranging, federally protected raptor species require monitoring frameworks that accommodate strong inference on the status of breeding populations across vast landscapes. We used a broad-scale sampling design to identify relationships between landscape conditions, detection rates, and site occupancy by territorial pairs of golden eagles in coastal southern California, United States. In 2016 and 2017, we surveyed 175 territory-sized sample sites (13.9-km 2 randomly selected grid cells) up to four times each year and detected a pair of eagles at least once in 22 (12.6%) sites. The probability of detecting pairs of eagles varied substantially between years and declined with increasing amounts of forest cover at survey sites, which obscured observations of eagles during ground-based surveys. After accounting for variable detection, the mean estimate of expected site occupancy by eagle pairs was 0.156 (SE = 0.081). Site-level estimates of occupancy were greatest (>0.30) at sample sites with more rugged terrain conditions, <20% human development, and lower amounts of scrubland vegetation cover. The proportion of a sample site with open grassland or forest cover was not strongly correlated with occupancy. We estimated that approximately 16% of the 5,338-km 2 sampling frame was used by resident pairs of golden eagles, corresponding to a sparsely distributed population of about 60 pairs (95% CI = 19 – 151 pairs). Our study provided baseline data for future surveys of golden eagles along with a widely applicable monitoring framework for identifying spatial conservation priorities in urbanizing landscapes.

California↗

USGS2020

Use of underwater videography to quantify conditions utilized by endangered Moapa Dace While spawning

Advances in underwater camera technology provide an affordable means to quantify the environmental conditions under which fish spawn. This information is important for investigating spawning ecology, managing habitat, or providing information for captive breeding programs. We deployed 12 modified security cameras underwater to identify environmental conditions related to the spawning behavior of the critically endangered Moapa Dace Moapa coriacea , a Mojave Desert stream-dwelling cyprinid that had never been observed spawning and that had fallen to a low of 459 individual fish 4 years prior to this study. Camera sites were selected systematically along the stream to represent the variety of conditions available. We divided the field of view in front of each camera into a grid, and we estimated both the available environment and the habitat over which Moapa Dace showed spawning behavior. From over 4,000 10-min video clips that were randomly selected for analysis, 13 spawning events were identified. Using nonparametric contingency table analyses, we found that Moapa Dace selected depths between 30 and 34 cm, water velocities between 0.11 and 0.17 m/s, cobble substrate, and overhead instream cover. Although the recorded sample size of spawning events was small (13), our sample represents a large proportion of events given that the world's entire population of Moapa Dace at the time was approximately 650 fish distributed over multiple kilometers of stream length. Environmental conditions identified by this study were replicated in laboratory facilities to successfully propagate Moapa Dace for the first time in captivity. These propagation methods are now used in a management setting by the Nevada Department of Wildlife to maintain a captive population of this rare fish. Camera methods can be effective in helping to identify spawning conditions where water clarity is sufficient.

Nevada↗

USGS2002

Occurrence of antibiotics in water from fish hatcheries

The recent discovery of pharmaceuticals in streams across the United States (Kolpin and others, 2002) has raised the visibility and need for monitoring of antibiotics in the environment. Possible sources of antibiotics and other pharmaceuticals in streams may include fish hatcheries. This fact sheet presents the results from a preliminary study of fish hatcheries across the United States for the occurrence and concentration of antibiotics present in fish hatchery water. The study examines both sufonamides and tetracyclines. Sulfonamides are synthetic compounds, and tetracyclines are naturally occurring compounds. The use of antibiotics added to specially formulated feed is a common practice in fish hatcheries to treat and prevent bacterial infections in large fish populations. U.S. Food and Drug Administration (FDA) approved antibiotics are oxytetracycline-HCI, sulfamerazine, and a combination drug containing ormetoprim and sulfadiamethoxine (U.S. Food and Drug Administration, 2003). During January 2001–June 2002, the U.S. Geological Survey (USGS) Organic Geochemistry Research Laboratory (OGRL), Lawrence, Kansas, cooperatively collected water samples from 13 fish hatcheries across the United States (fig. 1) with the assistance of hatchery operators. A method for the analysis of antibiotics was developed and used to identify and quantify these compounds in fish hatchery water (Lindsey and others, 2001). This study was completed to determine if trace levels of antibiotics [approximately 1 microgram per liter (μg/L) or 1 part per billion or greater occurred] in which water associated with fish hatcheries, which are a potential source of these compounds in surface water.

Colorado, Iowa, Kansas, New York, Oklahoma, Oregon↗

USGS2004

Sidescan sonar imagery and surficial geologic interpretation of the sea floor off Branford, Connecticut

The U.S. Geological Survey (USGS), in cooperation with the National Oceanic and Atmospheric Administration (NOAA) and the Connecticut Department of Environmental Protection (CT DEP), Figure 1 - Map of Study Areahas produced detailed geologic maps of the sea floor in Long Island Sound, a major East Coast estuary surrounded by the most densely populated region of the United States. These studies have built upon cooperative research between the USGS and the State of Connecticut that was initiated in 1982. The current phase of this research program is directed toward studies of sea-floor sediment distribution, processes that control sediment distribution, nearshore environmental concerns, and the relation of benthic community structures to the sea-floor geology. Anthropogenic wastes, toxic chemicals, and changes in land-use patterns resulting from residential, commercial, and recreational development have stressed the environment of the Sound, causing degradation and potential loss of benthic habitats (Koppelman and others, 1976; Long Island Sound Study, 1994). Detailed maps of the sea floor are needed to help evaluate the extent of adverse impacts and to help wisely manage resources in the future. Therefore, in a continuing effort to better understand Long Island Sound, we are constructing and interpreting sidescan sonar mosaics (complete-coverage acoustic images of the sea floor) within specific areas of special interest (Poppe and Polloni, 1998). The mosaic presented herein, which was produced during survey H11043 by NOAA 's Atlantic Hydrographic Branch, covers approximately 41.1 km 2 of the sea floor in north-central Long Island Sound off Branford, Connecticut. Shell bed provides shelter for juvenille skate.The mosaic and its interpretation serve many purposes, including: (1) defining the geological variability of the sea floor, which is one of the primary controls of benthic habitat diversity; (2) improving our understanding of the processes that control the distribution and transport of bottom sediments and the distribution of benthic habitats and associated infaunal community structures; and (3) providing a detailed framework for future research, monitoring, and management activities. The sidescan sonar mosaic also serves as a base map for subsequent sedimentological, geochemical, and biological observations, because precise information on environmental setting is important for selection of sampling sites and for appropriate interpretation of point measurements.

Connecticut↗