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Ecological Exposure Research Division Publications: 2003

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This page lists publication titles, citations and abstracts produced by NERL's Ecological Exposure Research Division for the year 2003, organized by Publication Type. Your search has returned 90 Matching Entries.

See also Ecological Exposure Research Division citations with abstracts: 1999,  2000,  2001,  2002,  2003,  2004,  2005,  2006,  2007,  2008,  2009

Technical Information Manager: Linda Ransick - (513) 569-7395 or ransick.linda@epa.gov

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Presented/Published
BOOK CHAPTER USEPA Biomonitoring and Bioindicator Concepts Needed to Evaluate the Biological Integrity of Aquatic Systems 06/01/2003
Lazorchak, J M., F H. McCormick, D L. Lattier, M J. Bagley, G P. Toth, B H. Hill, B S. Brown, V D. Engle, AND A. F. Maciorowski. USEPA Biomonitoring and Bioindicator Concepts Needed to Evaluate the Biological Integrity of Aquatic Systems. Chapter 14, B.A. Markert, A.M. Breure and H.G. Zechmeister (ed.), Bioindicators and Biomonitors. Elsevier Science Ltd, New York, NY, (2003).
Abstract: This chapter presents the current uses, concepts and anticipated future directions of biomonitoring and bioindicators in the regulatory and research programs of the United States Environmental Protection Agency (USEPA). The chapter provides a historical look on how biomonitoring and bioindicators evolved in the USEPA or its predecessor agencies from the 1960s - 1980s, then describes two current key biomonitoring and bioindicator programs, the USEPA Office of Research and Development's Environmental Monitoring and Assessment Program (EMAP) and USEPA's Office of Water's Biocriteria Program. The remainder of the chapter is organized hierarchially beginning with concepts and monitoring approaches using fish, macroinvertebrates and periphyton assemblages, and functional ecosystem measures. The assemblage approaches are followed by current research and regulatory use of whole organism toxicity testing assessments for measuring contamination in aquatic environments and remediation assessment. The chapter includes existing and proposed activities in the use of real-time biomonitoring to assess biological exposures to contaminants and other environmental changes. A new approach that uses small and large adult whole fish tissue as a bioindicator for assessing potential contaminant exposures to wildlife is presented, followed by a description of new research in molecular approaches to biomonitoring and bioindicators through measures of gene expression, use of microarrays and measures of genetic diversity.

JOURNAL Studies on Rare and Poorly Known Leeches (Annelida: Hirudinea: Glossiphoniidae) in Eastern North America 12/01/2003
Smith, D. G. AND D J. Klemm. Studies on Rare and Poorly Known Leeches (Annelida: Hirudinea: Glossiphoniidae) in Eastern North America. JOURNAL OF THE NORTH CAROLINA ACADEMY OF SCIENCE 119(4):137-149, (2003).
Abstract: Three taxa within the leech family Glossiphoniidae, Actinobdella inequiannulata, Placobdella hollensis, and Theromyzon spp., though widespread in eastern North America, remain poorly known with respect to their biology and systematics. All three taxa have been collected in New England and new information regarding their biology and anatomy have been recorded. A. inequiannulata broods eggs in a secreted sac, which is attached to the substrate and animal. The adult burrows and remains hidden under partially buried rocks during the brooding period. A. inequiannulata forms a sister group with Actinobdella pediculata within a polytypic genus group (Placobdella sensu lato). Placobdella hollensis is an active hunter and preys on both testudinate and mammal blood. The species has evolved several traits to undertake prey-seeking but retains the basic anatomical features of Placobdella sensu stricto. Theromyzon spp. is composed of several poorly known species and specimens collected in New England extend the range of the genus and show anatomical traits close to but not exactly as discussed for species elsewhere.

JOURNAL Behavior and Prey of Nesting Red-Shouldered Hawks in Southwestern Ohio 12/01/2003
Dykstra, C. R., J. L. Hays, M. M. Simon, AND F B. Daniel. Behavior and Prey of Nesting Red-Shouldered Hawks in Southwestern Ohio. JOURNAL OF RAPTOR RESEARCH 37(3):237-246, (2003).
Abstract: We used direct observations to quantify prey types, prey delivery rate, and adult and nestling behavior at nests of Red-shouldered Hawks (Buteo lineatus) in suburban southwestern Ohio. Twenty-one nests were observed for a total of 256 hr in 1997-2001. Small mammals made up the largest percentage of the identified prey (31.5%), followed by reptiles (22.7%), invertebrates (18.8%), amphibians (17.7%), birds (6.9%) and fish (2.5%). Season-long prey delivery rate averaged 3.5 +/- 0.6 prey items delivered per 4-hr observation period, or 116 +/- 19 g biomass delivered per 4-hr observation period. Weekly prey delivery rate showed no correlation with the age of the nestlings (p > 0.05). Adult attendance at the nest and time adults spent brooding nestlings both were negatively correlated with nestling age (P < 0.05). Time adults spent feeding nestlings was negatively correlated with nestling age (r2 - 0.92, P - 0.002), while time nestlings spent feeding themselves was positively correlated with nestling age (r2 - 0.92, P = 0.003). These data may serve as a baseline for assessing prey delivery rates and behavior of populations of Red-shouldered Hawks throughout the lower Midwest.

JOURNAL The Path from Molecular Indicators of Exposure to Describing Dynamic Biological Systems in An Aquatic Organism: Microarrays and the Fathead Minnow 12/01/2003
Miracle, A L., G P. Toth, AND D L. Lattier. The Path from Molecular Indicators of Exposure to Describing Dynamic Biological Systems in An Aquatic Organism: Microarrays and the Fathead Minnow. Ecotoxicology 12(6):457-462, (2003).
Abstract: The extent to which humans and wildlife are exposed to toxicants is an important focus of environmental research. This work has been directed toward the development of molecular indicators diagnostic for exposure to various stressors in freshwater fish. Research includes the discovery of genes indicative of environmental exposure in the USEPAs long-established aquatic toxicological organism, the fathead minnow (Pimephales promelas). Novel cDNAs and coding sequences will be used in DNA microarray analyses for pattern identification of stressor-specific, differentially up- and down-regulated genes. The methods currently used to discover genes in this organism, for which few annotated nucleic acid sequences exist, are cDNA subtraction libraries, differential display, exploiting PCR primers for known genes of other members of the family Cyprinidae and use of degenerate PCR primers designed from regions of moderate protein homology. Single or multiple genes noted as being differentially expressed in microarray analyses will then used in separate studies to measure bioavailable stressors in the laboratory and field. These analyses will be accomplished by quantitative RT-PCR (QRT-PCR). Moving from analysis of single gene exposures to the global state of the transcriptome offers possibilities that those genes identified by DNA microarray analyses might be critical components of dynamic biological systems and networks, wherein chemical stressors exert toxic effects through various modes of action. Additionally, the ability to discriminate bioavailability of stressors in complex environmental mixtures, and correlation with adverse effects downstream from these early molecular events, presents challenging new ground to be broken in the area of risk assessment.

JOURNAL Sensitivity of Indices of Biotic Integrity to Simulated Fish Assemblage Changes 11/12/2003
Trebitz, A S., B H. Hill, AND F H. McCormick. Sensitivity of Indices of Biotic Integrity to Simulated Fish Assemblage Changes. ENVIRONMENTAL MANAGEMENT 32(4):499-515, (2003).
Abstract: Multi-metric indices of biotic integrity (IBI) are commonly used to assess condition of stream fish assemblages, but their ability to monitor trends within streams over time is largely unknown. We assessed the trend detection ability of two IBI formulations (one with traditional scoring and metrics, and one with nontraditional scoring and region-specific metrics) and of similarity and diversity indices using simulations that progressively altered the fish assemblages of 39 streams in the United States mid-Atlantic Highlands region. We also assessed responses to simulated 50% variability in fish abundances, as a measure of background "noise". Fish assemblage indices responded little to changes that affected all species proportionally despite substantial changes in total fish number. Assemblage indices responded better to scenarios that differentially affected fish species, either according to life history traits or by increasing dominance of already common species, but even these changes took some time to detect relative to background variability levels. Ordinations of stream fish assemblage data suggested that differences among sites were maintained even after substantial alterations of fish composition within sites. IBIs are designed to detect broad assemblage differences among sites while downplaying abundance changes and variability increases that were the first indications of within-site changes, and they appear more suited to detecting large departures from natural fish assemblages than for monitoring gradual changes such as those our simulations produced. Inferences about causes of assemblage changes should be made with caution because of correlations among species traits and interdependence among IBI component metrics. Site trend assessments should be made based on all available data rather than just by summary indices.

JOURNAL The U.S. Environmental Protection Agency's Stressor Identification Guidance: A Process for Determining the Probable Causes of Biological Impairments 10/01/2003
Cormier, S M., S B. Norton, AND G Suter. The U.S. Environmental Protection Agency's Stressor Identification Guidance: A Process for Determining the Probable Causes of Biological Impairments. HUMAN AND ECOLOGICAL RISK ASSESSMENT 9(6):1431-1443, (2003).
Abstract: The United States Environmental Protection Agency (USEPA) has ongoing programs to encourage the evaluation of stream condition based on biological indicators. Bioassessments reveal impairments but do not identify causes of impairments, a necessary step in the restoration of aquatic life. Furthermore, changes in biological conditin are often caused by multiple stressors (chemical, physical, biological). To address this need, the USEPA has developed guidance to identify probable causes of biological impairments in aquatic ecosystems and to provide a structure for organizing the scientific evidence to make a credible case. The concepts and organizational structure of the process have potential applications to most ecoepidemiological investigations.

JOURNAL Seasonal Foraging By Channel Catfish on Terrestrially Burrowing Crayfish in a Floodplain-River Ecosystem 09/01/2003
Flotemersch, J E. AND D. C. Jackson. Seasonal Foraging By Channel Catfish on Terrestrially Burrowing Crayfish in a Floodplain-River Ecosystem. ECOHYDROLOGY AND HYDROBIOLOGY 3(1):61-70, (2003).
Abstract: The seasonal use of terrestrially burrowing crayfish as a food item by channel catfish Ictalurus punctatus was studied in channelized and non-channelized sections of the Yockanookany River (Mississippi, USA). During seasonal inundation of the floodplains, the crayfish occupied open water on the floodplains. Adult catfish aggregated in locations where the river channel and floodplain were coupled and subsequently foraged heavily on the crayfish. Decoupling floodplains from the river by flood control activities such as channelization, dredging and levee construction can modify channel catfish stock interactions with terrestrially burrowing crayfish and reduce potential benefits from this foraging.

JOURNAL Organochlorine Contaminants in Sea Turtles from the Eastern Pacific 09/01/2003
Gardner, S. C., M. D. Pier, R Wesselman, AND J. A. Juarez. Organochlorine Contaminants in Sea Turtles from the Eastern Pacific. MARINE POLLUTION BULLETIN 46(9):1082-1089, (2003).
Abstract: We measured organochlorine residues in three species of sea turtles from the Baja California peninsula, Mexico. Seventeen of 21 organochlorine pesticides analyzed were detected, with heptachlor epoxide and y-hexachlorocyclohexane the most prevalent in 14 (40%) and 11 (31%) of the 35 tissue samples, respectively. PCBs were detected in all but one of the 9 turtles studied, with congener 18 of the most commonly detected in 8 (23%) of the samples. The dioxin-like congeners 118 and 180 were detected in 4 (11%) and 3 (9%) of the samples, respectively. Percent contribution of congeners was negatively correlated to their octanol-water partition coefficients, with kidney and muscle containing more lower-chlorinated congeners than liver or adipose samples. Levels of organochlorines detected in the present study were low, potentially attributable to the feeding habits of the predominant species collected in this study (herbivorous) and/or the samples obtained in an unindustrialized region.

JOURNAL Biology of the Leech Actinobdella Inequiannulata Moore, 1901 (Annelida: Hirudinea: Rhynchobdellida: Glossiphoniidae), Parasitic on the White Sucker, Catostomus Commersoni Lacepede, 1803 and the Longnose Sucker, Catostomus Catostomus Forster, 1773, in Algonquin Provincial Park, Ontario, Canada 07/01/2003
Klemm, D J., B. A. Daniels, W. E. Moser, AND R. G. Lester. Biology of the Leech Actinobdella Inequiannulata Moore, 1901 (Annelida: Hirudinea: Rhynchobdellida: Glossiphoniidae), Parasitic on the White Sucker, Catostomus Commersoni Lacepede, 1803 and the Longnose Sucker, Catostomus Catostomus Forster, 1773, in Algonquin Provincial Park, Ontario, Canada. COMPARATIVE PARASITOLOGY 70(2):120-127, (2003).
Abstract: Actinobdella inequiannulata was found on the white sucker, Catostomus commersoni, and less frequently on the longnose sucker, Catostomus catostomus, in Algonquin Provincial Park, Ontario, Canada. Catostomus commersoni parasitized with Act. inequiannulata was collected from July to October, 1973 and May to October, 1974. In May and October, less than 3% of the fish carried leeches. In July, 80% of the fish were parasitized with an average of 1.5 leeches per fish. Observations on leech weight suggest young leeches attach to fish from May to September, some mature in July, and a second generation of leeches re-parasitize the fish in August and September. The mean size of leeches on suckers increased from May until July, after which size remained relatively constant. Leeches produced characteristic lesions on the opercula of suckers. Fully-developed lesions on fish opercula produced by aggregated leeches had varying amounts of central erosion, extravasation, dermal and epidermal hyperplasia, and necrosis.

JOURNAL Development of a Multimetric Index for Assessing the Biological Condition of the Ohio River 07/01/2003
Emery, E. B., T. P. Simon, F H. McCormick, P. L. Angermeier, J. E. DeShon, C. O. Yoder, R. E. Sanders, W. D. Pearson, G. D. Hickman, R. J. Reash, AND J. A. Thomas. Development of a Multimetric Index for Assessing the Biological Condition of the Ohio River. TRANSACTIONS OF THE AMERICAN FISHERIES SOCIETY 132(4):791-808, (2003).
Abstract: The use of fish communities to assess environmental quality is common for streams, but a standard methodology for large rivers is largely undeveloped. We developed an index to assess the condition of fish assemblages along 1580 km of the Ohio River. Representative samples of the fish assemblages were collected from 1991 to 2001, using stardardized nighttime boat-electrofishing techniques, from 709 Ohio River reaches, including 318 "least-impacted" sites. We evaluated 55 candidate metrics based on attributes of fish assemblage structure and function to derive a multimetric index of river health. We examined the stability of metrics based against habitat features and assessed the responsiveness of metrics to anthropogenic disturbance, i.e. effluents, turbidity, and highly embedded substrates. The resulting Ohio River Fish Index (ORFIn) comprises thirteen metrics that were selected because they responded predictably to measures of human disturbance or reflected desirable features of the Ohio River. We retained two metrics (number of intolerant species and number of sucker species) from Karr's original Index of Biotic Integrity (IBI). Six metrics were modified from indices developed for the upper Ohio River (number of native species, number of great river species, number of centrarchid species, DELT anomalies, percent individuals as simple lithophils, and percent individuals as tolerant species). We also incorporated three trophic metrics (percent of individuals as detritivores, invertivores, and piscivores, respectively), a metric based on catch-per-unit-effort, and one on the percent of individuals as non-indigenous fish species. The ORFIn declined significantly where anthropogenic effects on substrate and water quality were prevalent and was significantly lower in the first 500m below point-source discharges than at control sites nearby. Although additional research on the temporal stability of the metrics and index will likely enhance the ORFIn's reliability, its incorporation into Ohio River assessments still represents an improvement over current physicochemical protocols.

JOURNAL Development and Evaluation of a Macroinvertebrate Biotic Integrity Index (Mbii) for Regionally Assessing Mid-Atlantic Highlands Streams 05/01/2003
Klemm, D J., K A. Blocksom, F A. Fulk, A. T. Herlihy, R M. Hughes, P R. Kaufmann, D V. Peck, J L. Stoddard, W T. Thoeny, M. B. Griffith, AND W. S. Davis. Development and Evaluation of a Macroinvertebrate Biotic Integrity Index (Mbii) for Regionally Assessing Mid-Atlantic Highlands Streams. ENVIRONMENTAL MANAGEMENT. Springer-Verlag, New York, NY, 31(5):656-669, (2003).
Abstract: The multimetric Macroinvertebrate Biotic Integrity Index (MBII) was developed from data collected at 574 wadeable stream reaches in the Mid-Atlantic Highlands region (MAHR) by the USEPA's Environmental Monitoring and Assessment Program (EMAP). Over 100 candidate metrics were evaluated for their range, precision, responsiveness to various disturbances, relationship to catchment area, and redundancy. Seven metrics were selected, representing taxa richness, assemblage composition, pollution tolerance, and a functional feeding group. We scored metrics and summed them, then ranked the resulting index through use of independently-evaluated reference stream reaches. Although sites were classified into lowland and upland ecoregional groups, we did not need to develop separate scoring criteria for each ecoregional group. We found that we could use the same metrics for pool and riffle composite samples, but we had to score them differently. Using the EMAP probability design, we inferred the results, with known confidence bounds, to the 167,797 kilometers of wadeable streams in the Mid-Atlantic Highlands. We classified 17% of the target stream length in the MAHR as good, 57% as fair, and 26% as poor. Pool-dominated reaches were relatively rare in the MAHR, and the usefulness of the MBII was more difficult to assess in these reaches. The MBII was effective in evaluating region-wide conditions and distinguishing clean and impaired reaches among both upland and lowland streams dominated by riffle habitat.

JOURNAL A Performance Comparison of Metric Scoring Methods for a Multimetric Index for Mid-Atlantic Highlands Streams 05/01/2003
Blocksom, K A. A Performance Comparison of Metric Scoring Methods for a Multimetric Index for Mid-Atlantic Highlands Streams. ENVIRONMENTAL MANAGEMENT. Springer-Verlag, New York, NY, 31(5):670-682, (2003).
Abstract: When biological metrics are combined into a multimetric index for bioassessment purposes, individual metrics must be scored as unitless numbers to be combined into a single index value. Among different multimetric indices, methods of scoring metrics may vary widely in the type of scaling used and the way in which metric expectations are established. These differences among scoring methods may influence the performance characteristics of the final index that is created by summing individual metric scores. The Macroinvertebrate Biotic Integrity Index (MBII), a multimetric index, was developed for first through third order streams in the Mid-Atlantic highlands of the U.S. The relationship of the MBII to site condition and temporal and within-sample variability were evaluated for six metric scoring methods. Measures of index variability were affected to a greater degree than those of index responsiveness by both the type of scaling (discrete or continuous) and the method of setting expectations. A scoring method using continuous scaling and setting metric expectations using the 95th percentile of the entire distribution of sites performed the best overall for the MBII. These results showed that the method of scoring metrics affects the properties of the final index, particularly variability, and should be examined in developing a multimetric index because these properties can affect the number of condition classes (e.g., unimpaired, moderately impaired, severely impaired) an index can distinguish.

JOURNAL Development of Codominant Markers for Identifying Species Hybrids 04/01/2003
Tranah, G. J., M J. Bagley, J. J. Agresti, AND B. May. Development of Codominant Markers for Identifying Species Hybrids. CONSERVATION GENETICS 4(4):537-541, (2003).
Abstract: Herein we describe a simple method for developing species-diagnostic markers that would permit the rapid identification of hybrid individuals. Our method relies on amplified length polymorphism (AFLP) and single strand conformation polymorphism (SSCP) technologies, both of which can be performed in any molecular biology facility using standard laboratory equipment. We demonstrate the utility of the AFLP-SSCP method by developing three taxon-specific markers that will be suitable for monitoring introgression in endangered Klamath basin suckers.

JOURNAL Analysis of Macroinvertebrate Assemblages in Relation to Environmental Gradients Among Lotic Habitats of California's Central Valley 03/01/2003
Griffith, M. B., P. Husby, R. K. Hall, P R. Kaufmann, AND B H. Hill. Analysis of Macroinvertebrate Assemblages in Relation to Environmental Gradients Among Lotic Habitats of California's Central Valley. ENVIRONMENTAL MONITORING AND ASSESSMENT 82(3):281-309, (2003).
Abstract: We analyzed relationships between environmental characteristics and macroinvertebrate assemblages in lotic habitats of California's Central Valley with community metric and multivariate statistical approaches. Using canonical ordination analyses, we contrasted results when assemblage structure was assessed with macroinvertebrate metrics, as suggested for use in indices of biotic integrity, or with genera abundances. Our objectives were to identify metrics or taxa diagnostic of lotic environmental stressors and compare the capacity of these approaches to detect stressors in order to suggest how they might be used to diagnose stressors. For macroinvertebrate metrics, redundancy analysis (RDA) extracted three axes correlated with channel morphology and substrates. For genera abundances, canonical correspondence analysis (CCA) extracted two axes correlated with soluble salts and with channel morphology and substrates but did not separate these gradients onto different axes. Cluster analysis identified five RDA and five CCA site groups, which exhibited differences for environmental variables, metrics, or genera abundances, and agreement between the analyses in partitioning of sites was greater than if sites were partitioned randomly. These approaches differ in their ability to detect environmental stressors, because they measure different aspects of assemblages and would be complementary in design of new metrics diagnostic of stressors.

JOURNAL Contamination of Fish in Streams of the Mid-Atlantic Region: An Approach to Regional Indicator Selection and Wildlife Assessment 03/01/2003
Lazorchak, J M., F H. McCormick, T R. Henry, AND A. T. Herlihy. Contamination of Fish in Streams of the Mid-Atlantic Region: An Approach to Regional Indicator Selection and Wildlife Assessment. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 22(3):545-553, (2003).
Abstract: The extent of contamination of fish in the Mid-Atlantic Region was evaluated as part of the U.S. Environmental Protection Agency's Monitoring and Assessment Program's regional assessment in 1993 through 1994. Fish assemblages from wadeable streams were dominated by small, short-lived fishes (e.g., minnows, darters, and sculpins) that were more widely distributed and abundant than large fishes typically chosen for tissue contaminant studies (e.g., trout, black bass, sunfish, common carp). Chemical concentrations in whole fish homogenates exceeded detection limits for mercury, DDT and polychlorinated biphenyls (PCBs) in 75 to 100% of the stream length assessed using small fishes and 84 to 100% of the stream length assessed using large fishes. Wildlife values (WVs) representing a threshold for toxic effect were developed to allow examination of the spatial extent of potential risk to piscivorous wildlife. For mercury, DDT, dieldrin, and chlordane, estimates of the regional extent of streams where fish contaminant concentrations exceeded the WVs were greater when based on small fishes than on large fishes. However, within the distribution of stream lengths assessed using small and large fishes the percentage of stream kilometers exceeding the WVs were quite similar. Our data demonstrate that the greater abundance and distribution of small, short-lived fishes provide greater estimates of regional extent of contamination for first- through third-order streams and can be used for regional assessments of potential exposure and effects in wildlife.

JOURNAL Minimizing Cognitive Errors in Site-Specific Causal Assessment 02/01/2003
Norton, S B., L E. Rao, G Suter, AND S M. Cormier. Minimizing Cognitive Errors in Site-Specific Causal Assessment. HUMAN AND ECOLOGICAL RISK ASSESSMENT 9(1):213-229, (2003).
Abstract: Interest in causal investigations in aquatic systems has been a natural outgrowth of the increased use of biological monitoring to characterize the condition of resources. Although biological monitoring approaches are critical tools for detecting whether effects are occurring, they do not identify the cause of the observed effects. Formal approaches to causal evaluation can provide a mechanism to build on expert knowledge, increasing the likelihood that remedial efforts will achieve the desired environmental improvement. This paper examines how formal approaches to causal investigations minimize common errors. We reviewed common cognitive errors reported in the literature, and compared them with considerations suggested for strength-of-evidence approaches. Many of the causal considerations are directed toward distinguishing spurious correlations from true causal relationships. However, this is only one type of erorr; others include hypothesis dependance, confirmation bias, hypothesis tenacity and anchoring. We suggest three general principles for minimizing error in site-specific investigations: 1) conduct the causal evaluation as a fair, transparent comparison among alternatives; 2) carefully quantify the conjunction of cause and effect; and 3) consider that conjunction between cause and effect is spurious, or that a real conjunction was masked.

NON-EPA PUBLISHED PROCEEDINGS Hyperspectral Remote Sensing of Water Quality Parameters for Large Rivers in the Ohio River Basin 10/01/2003
Shafique, N A., B C. Autrey, F A. Fulk, AND J E. Flotemersch. Hyperspectral Remote Sensing of Water Quality Parameters for Large Rivers in the Ohio River Basin. First Interagency Conference on Research in the Watersheds, BENSON, AZ, October 27 - 30, 2003. USDA Agricultural Research Service, Washington, DC 216-221, (2003).
Abstract: Optical indicators of water quality have the potential of enhancing the abilities of resource managers to monitor water bodies in a timely and cost-effective manner. However, the degree to which optical indicators are useful may depend on their applicability to data collected from multiple water bodies. In 1999, a Compact Airborne Spectrographic Imager (CASI) was flown over the relatively shallow Great Miami River (GMR), Ohio, collecting hyperspectral bands of data. Concurrently, water quality parameters were measured, and water samples and spectrometer data were collected directly from the river. Using correlations between the ground-truth data and combinations of bands from the remotely sensed data, spectral indices were developed which could be used to estimate chlorophyll a, turbidity and phosphorus. In 2001, a similar study was conducted in which a CASI was flown over a portion of the relatively deep Ohio River while ground-truth data were collected. These data were analyzed and tested against the spectral indices developed during the 1999 study. The GMR's spectral index for chlorophyll a was applicable to the Ohio River data. However, slightly refined spectral indices for turbidity and phosphorus were required.
This study demonstrates the ubiquitous applicability of the chlorophyll a spectral index while revealing the limited applicability of the turbidity and phosphorous spectral indices. Although differences between the dynamics of the two rivers may have made these spectral indices incompatible, with further refinement they may yet prove to be broadly applicable tools in the detection and measurement of potential water quality problems.

PRESENTATION Reduced Benthic Macroinvertebrates Diversity in the Willimantic River, Connecticut 12/12/2003
Cormier, S M., S B. Norton, G Suter, C. Bellucci, AND G. Hoffman. Reduced Benthic Macroinvertebrates Diversity in the Willimantic River, Connecticut. Presented at Connecticut DEP, Hartford, CT, December 12, 2003.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION Use of Crayfish By Channel Catfish in a Floodplain River Ecosystem 12/08/2003
Flotemersch, J E. Use of Crayfish By Channel Catfish in a Floodplain River Ecosystem. Presented at 2003 Midwest Fish and Wildlife Conference, Kansas City, MO, December 7-10, 2003.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION Phylogeographic Patterns in Large River Ecosystems: Genetic Structure of Smallmouth Buffalo (Ictiobus Bubalus) in the Ohio River 12/07/2003
Sloss, B. L., M J. Bagley, F H. McCormick, AND E. B. Emery. Phylogeographic Patterns in Large River Ecosystems: Genetic Structure of Smallmouth Buffalo (Ictiobus Bubalus) in the Ohio River. Presented at 2003 Midwest Fish and Wildlife Conference, Kansas City, MO, December 7-10, 2003.
Abstract: Genetic studies on populations of large river fishes provide a potentially useful but underutilized research and assessment tool. Population genetic research on freshwater systems has provided meaningful insight into stock structure, hybridization issues, and gene flow/migration. However, most genetic research has concentrated on stream and lake ecosystems, not populations of large river fishes. In general, populations of large river fishes have several characteristics that are unfavorable for molecular ecology research, especially large population sizes and high levels of migration. As a result, the metapopulation dynamics of big river fishes are poorly understood. Recent ichthyological research examining fish community structure and dynamics throughout the Ohio River has shown patterns consistent with three recognized reaches of the river (upper, middle, and lower) and consistent with biogeographical patterns reflecting the ancestral Teays River drainage. The smallmouth buffalo (Ictiobus bubalus) is a long-lived, large river fish species found throughout the Ohio River. As such, it represents an ideal "model" fish to examine large river metapopulational patterns. In an effort to examine fine-scale genetic structuring in the river, we sampled 357 smallmouth buffalo throughout the Ohio River, including representatives from 16 putative populations during the spring/summer 2001. Mitochondrial DNA sequences for the ND2 gene and nuclear microsatellite DNA variation were analyzed for evidence of population fragmentation and subdivision (phylogeographical patterns) throughout the river by phylogenetic and nested-clade analyses. Resolved patterns of genetic diversity will be discussed in terms of impacts due to maintenance of navigational channels, hydrological manipulations, and historical biogeographical influences.

PRESENTATION Genomics and Environmental Research 11/17/2003
Miracle, A L. Genomics and Environmental Research. Presented at 2003 BioNorth Conference, Ottawa, Canada, November 17-19, 2003.
Abstract: The impact of recently developed and emerging genomics technologies on environmental sciences has significant implications for human and ecological risk assessment issues. The linkage of data generated from genomics, transcriptomics, proteomics, metabalomics, and ecology can be linked together through bioinformatics to generate a clear picture of events occurring within a given organism, or collection of organisms from source of stressor(s) through outcome of exposure. Recognition of the roles government, academic, and private industry research all provide to increase knowledge and build exposure-to-outcome databases will become important in collecting the diverse ecotoxicogenomic data sets required to effectively reduce uncertainties in comprehensive risk assessment for the environment and human health. The power of genomics technologies offers a genome wide, dynamic picture of biological systems. The development of microarray technologies permits thousands of genes to be screened in a single experiment to establish differential gene expression in stressor-treated versus control cell and tissue populations. Microarrays have been used to study issues in pathology, pharmacology, oncology, cell biology, and recently, toxicology. With the advent of whole genome information readily available for select organisms, with the promise of additional, ecologically-relevant organism genomic information, microarrays can be generated to sample a significant portion of the globally expressed genome. Genomic information combined with microarray technology has revolutionized the ability to discern mechanistic pathways involved in disease processes, development, and toxicant action.

Several laboratories within the EPA's Office of Research and Development have come together to provide a framework for integration of genomics technologies within the risk assessment paradigm and produce a computational toxicology program for assessing risk to human health and ecosystems. The amount of data generated from such a multi-disciplinary approach will necessitate rigorous standardization of experimental design and data interpretation for using ecotoxicogenomic data in a regulatory context.

PRESENTATION Assessment of Differential Gene Expression in Sheepshead Minnows Exposed to Environmental Estrogens 11/10/2003
Knoebl, I, M J. Hemmer, AND N D. Denslow. Assessment of Differential Gene Expression in Sheepshead Minnows Exposed to Environmental Estrogens. Presented at Society of Environmental Toxicology and Chemistry, Austin, TX, November 9-13, 2003.
Abstract: Gene arrays and quantitative real-time PCR (Q-PRC) are sensitive methods for assessing exposure of fish and other wildlife to environmental contaminants by measuring changes in gene expression. Several genes normally induced by estradiol in female fish, those for vitellogenins (VTGs) and zona radiata proteins (ZRPs) are also inducible in males exposed to estrogenic chemicals. We developed Q-PCR assays to measure the hepatic mRNA expression of VTG 1 and VTG 2 as well as ZRP 2 and ZRP 3. We exposed male sheepshead minnows (SHM, Cyprinodon variegatus) to varying concentrations of estradiol (50 to 500 ng/L) to determine a dose-response. Exposure to estradiol elicited a dose-dependent increase in all four genes tested. VTG 2 was expressed at about a 10-fold lower level than VTG 1, and ZRP 2 expression was lower than ZRP 3. To determine other genes that may be differentially regulated by environmental estrogens, we used several methods including differential display RT-PCR and suppressive subtractive hybridization in hepatic mRNA of SHM exposed to methoxychlor and paranonylphenol (PNP). We have identified additional genes induced by those chemicals including genes for regulatory signaling molecules, catalytic proteins and transport proteins among others. These genes will be added to an existing panel of estrogen-responsive genes and evaluated on a gene array. The arrays will be useful to expand known gene expression profiles and elucidate other pathways involved in response to environmental contaminants.

PRESENTATION Evaluation of Macroinvertebrate Trends in Streams Vulnerable to Acid Deposition in the Mid-Atlantic Highlands Region of the U.S.A. 11/08/2003
Klemm, D J., K A. Blocksom, A. T. Herlihy, AND W T. Thoeny. Evaluation of Macroinvertebrate Trends in Streams Vulnerable to Acid Deposition in the Mid-Atlantic Highlands Region of the U.S.A. Presented at Society of Environmental Toxicology and Chemistry, Austin, TX, November 8-13, 2003.
Abstract: Benthic macroinvertebrate and water chemistry samples were collected from wadeable stream sites in the Mid-Atlantic Highlands region of the U.S. during 1993-1995 and 2001 in support of USEPA's TIME (Temporally Integrated Monitoring of Ecosystems) Progam. This study was designed to measure the effects of acid deposition and the long-term trends at sites sensitive to acid deposition in response to emission reductions associated with the 1990 Clean Air Act Amendments. An ordination of stream sites using 1993-1995 macroinvertebrate species abundance data showed a strong pH gradient and clear separation between sites vulnerable and non-vulnerable to acid deposition. When these sites were assigned to five acid sensitivity classes based on acid neutralizing capacity, those in the chronically and episodically acidic classes had lower scores of the Macroinvertebrate Biotic Integrity Index (MBII). The more sensitive classes had fewer caddisfly and mayfly taxa, as well as lower collector-filterer taxa richness and a higher percentage in the 5 dominant taxa. Between 1993-1995 and 2001 at sites vulnerable to acid deposition, MBII scores improved by an average of 15 points on a 100-point scale. These increases in index scores reflected increases in mayfly, caddisfly, and collector-filterer richness and decreases in the percent dominant 5 taxa.

PRESENTATION Vitellogenin Gene Expression in Fathead Minnows Exposed to Ee2 in a Whole Lake Dosing Experiment 11/08/2003
Lazorchak, J M., R Flick, D L. Lattier, K. Kidd, V. Palace, M E. Smith, B E. Wiechman, T. Hodge, AND G P. Toth. Vitellogenin Gene Expression in Fathead Minnows Exposed to Ee2 in a Whole Lake Dosing Experiment. Presented at Society of Environmental Toxicology and Chemistry, Austin, TX, November 8-13, 2003.
Abstract: A whole-lake endocrine disruption experiment was conducted by Fisheries and Oceans Canada at the Experimental Lakes Area (ELA), northwestern Ontario in 2001 and 2002. This experiment examined population, organism, biochemical and cellular-level effects in lake trout, white sucker, fathead minnow, and pearl dace exposed to environmentally-relevant (4-6 ng/L) concentrations of the synthetic estrogen, 17a ethynylestradiol. The USEPA collaborated in this study by evaluating vitellogenin gene expression (Vtg) in male fathead minnow livers: 1) from indigenous fish collected from the dosed and control lakes four times, once before dosing and up to three times after dosing; 2) in 2001 from indigenous minnows collected from the control lake and deployed for 1, 3, 7 and 13 days in the dosed and control lakes; and 3) in 2001 and 2002 from Cincinnati cultured minnows exposed to water collected from both ELA lakes and shipped to Cincinnati. RT-PCR methods were used for measuring Vtg expression. In addition to water exposures, embryo-larval fish were exposed to control and dosed lake sediment elutriates for 5 days. Gene expression in indigenous male fatheads collected at all time intervals from the dosed lake showed a constant level of elevation. Gene expression in the 2001 deployment study was detected within 24 hours after deployment of control fish into the treated lake and stayed elevated for the entire 13-day study. Highly variable gene expression was found in fry exposed to dosed lake sediments but no significant gene expression was found in fry exposed to control lake sediments. Results indicate that RT-PCR analyses of total RNA can be used to provide a rapid and timely estimate of exposure to estrogenic substances.

PRESENTATION Microsatellite Dna Variation in Two Fathead Minnow (Pimephales Promelas) Stocks 11/08/2003
BrownAugustine, M. C., S. I. Guttman, AND M J. Bagley. Microsatellite Dna Variation in Two Fathead Minnow (Pimephales Promelas) Stocks. Presented at Society of Environmental Toxicology and Chemistry, Austin, TX, November 8-13, 2003.
Abstract: Adverse effects on more than 2000 species of fish in the U.S. and Canada are estimated by sensitvity results of fathead minnow (Pimephales promelas) acute toxicity tests. Whether survival and susceptibility to toxicants are influenced by genetic variation is still under question. This work is part of a larger study to assess the importance of genetic variation in the fathead minnow and to quantify genetic components of copper resistance. Two populations of fathead minnows were examined for microsatellite DNA variation. Genetic variation differed between and within stocks, as shown by number of alleles, expected heterozygosity, and gene frequency.

PRESENTATION National Screening Survey of Edcs in Municipal Wastewater Treatment Facilities 11/08/2003
Lazorchak, J M., M E. Smith, D L. Lattier, B E. Wiechman, A Braam, G P. Toth, R C. Brenner, AND G D. Sayles. National Screening Survey of Edcs in Municipal Wastewater Treatment Facilities. Presented at Society of Environmental Toxicology and Chemistry, Austin, TX, November 8-13, 2003.
Abstract: In 2002 and 2003 the USEPA's Office of Research and Development asked Regional EPA inspectors, state EPA inspectors and municipal plant operators to collect four gallons effluent, either as a grab or composite sample, from up to 50 wastewater treatment plants (WWTP), and ship them to Cincinnati for male and female fathead minnow exposures. The purpose of this study was to assess whether certain types of treatment plants or operations are more effective in removing endocrine disrupting chemicals (EDCs). To do this, five male and five female fathead minnows were exposed to each effluent for 24 hours, their livers were necropsied and RNA extracted and analyzed via real-time PCR for changes in vitellogenin gene expression (Vg). Each effluent assessed included two laboratory control waters (moderately hard reconstituted water with and without DMSO) and one positive control, 5 ng/L of the estrogen Ethynylestradiol (EE2). If males showed Vg levels above controls, then this would indicate the presence of an androgen or anti estrogen. Fifty-two total WWTP samples were tested from effluents in all ten USEPA Regions and representing 23 states, including Alaska and Hawaii. Six samples resulted in 100% mortality in the effluent sample being tested. Three effluents were resampled and tested. Of the 46 that were not acutely toxic, 10 (21.7%) showed elevated Vg levels in male fathead minnows and two (4.3%) showed reduced Vg levels in female fathead minnows. Two effluents that showed elevated levels in males were repeated and showed similar results.

PRESENTATION Proposed Water Quality Surveillance Network Using Physical, Chemical and Biological Early Warning Systems (Cbews) 11/08/2003
Lazorchak, J M., H. J. Allen, R Haught, D L. Lattier, AND J A. Goodrich. Proposed Water Quality Surveillance Network Using Physical, Chemical and Biological Early Warning Systems (Cbews). Presented at Society of Environmental Toxicology and Chemistry, Austin, TX, November 8-13, 2003.
Abstract: The Homeland Protection Act of 2002 specifically calls for the investigation and use of Early Warning Systems (EWS) for water security reasons. The EWS is a screening tool for detecting changes in source water and distribution system water quality. A suite of time-relevant biological and physical/chemical water quality monitors applied in an EWS can provide timely information to aid decision-makers in the management and protection of the nation's water resources and measure the success of water quality control programs implemented under the Clean Water Act. A suite of monitors is necessary because no single organism will be sensitive to all contaminants at relevant concentrations. Current CBEWS in Europe use fish, bivalves, arthropods, and bacteria and are capable of detecting contaminants at relatively short time periods (hours). Strategic placement of water quality monitors in locations of high vulnerability in both source water and distribution systems may detect the presence of unsuspected chemicals or toxic interactions occurring as a result of spills, legal or illegal discharges, or intentional introductions. This work couples the "canary in the coal mine" approach with the latest in behavioral, physiological, and physical/chemical monitoring techniques and current computing and communications equipment, to provide time-relevant data over a range of spatial scales (e.g., watersheds or regions). We propose to go beyond the Euopean approach by investigating the use of a combination of advanced technologies that are time-relevant whole organism and molecular biosensing methods. Ultimately, we envision setting up a continuous, time-relevant national water quality surveillance network in all major rivers in the U.S. that are used for water supplies and their distribution systems. Complimenting whole organism systems will be molecular measures on fish and invertebrates using microarray technologies and near-real-time PCR methods for measuring gene expression.

PRESENTATION Investigating Causes of Biological Impairments in Aquatic Systems: A Plan for Development of the Causal Analysis/Diagnosis Decision 11/08/2003
Norton, S B., S M. Cormier, L E. Rao, G Suter, P ShawAllen, B. Swietlik, K S. Minamyer, B Subramanian, AND B C. Autrey. Investigating Causes of Biological Impairments in Aquatic Systems: A Plan for Development of the Causal Analysis/Diagnosis Decision. Presented at Society of Environmental Toxicology and Chemistry, Austin, TX, November 8-13, 2003.
Abstract: Increasingly, the regulatory, remedial and restoration actions taken to manage impaired environments are based on measurement and analysis of the biotic community. When an aquatic community has been identified as impaired, the cause of the impairment must be determined so that appropriate actions can be taken. The USEPA's Stressor Identification (SI) Guidance describes a methodology for identifying the causes of observed impairments in aquatic systems. Stressor identification requires extensive knowledge of the mechanism, symptoms, and stressor-response relationships for various specific stressors as well as the ability to use that knowledge in a formal method for causal analysis.
This poster describes the first version of the Causal Analysis/Diagnosis Decision Information System (CADDIS). CADDIS is envisioned as a decision support system that will help investigators in the regions, states and tribes find, access, organize, use and share information useful for causal evaluations in aquatic systems. It will include supporting case studies and causal analysis tools. Future versions will be developed incrementally and iteratively, and frequent user input and feedback will be essential to the system's success.

PRESENTATION Using Genomics to Examine Multiple Exposure Variables in Bioindicators Research 11/08/2003
Miracle, A L. AND D L. Lattier. Using Genomics to Examine Multiple Exposure Variables in Bioindicators Research. Presented at Society of Environmental Toxicology and Chemistry, Austin, TX, November 8-13, 2003.
Abstract: Genomics technologies provide a powerful tool for rapid assessment of differentially expressed genes in laboratory and field animals exposed to toxicants, and a means by which to link the earliest indicators of exposure to diverse effects in organisms and populations. However, application of these new technologies can be challenging when applied to an environmental model organism that has not been historically used in basic biological research. Because there is very little gene sequence information for the standard aquatic toxicology organism, fathead minnow (Pimephales promelas), a unique approach was developed to examine specific gene expression in response to a potent estrogenic stressor across dose and age variables. Exposure-specific subtractive cDNA libraries were constructed from adult liver using 17a-ethynylestradiol (EE2) at nominal, but environmentally relevant concentrations (5 ppt). The resulting differentially expressed cDNA clones were arrayed on a glass slide microarray platform and examined for differences among individuals, life stages, and chemical concentrations. Our data suggest that gene expression profiling will provide a sensitive measure of response to environmental estrogens when analyzed in context of various developmental stages and inter-individual variations. Thus, the use of genomics and microarray technologies to examine gene expression promises to be a powerful tool in understanding environmental exposures and subsequent impacts.

PRESENTATION Development of a Fathead Minnow Model for Evaluating Exposure of Fish to Genotoxic Substances 11/08/2003
Meier, J R., L W. Chang, P A. Wernsing, S E. Franson, AND J M. Lazorchak. Development of a Fathead Minnow Model for Evaluating Exposure of Fish to Genotoxic Substances. Presented at Society of Environmental Toxicology and Chemistry, Austin, TX, November 8-13, 2003.
Abstract: The fathead minnow (FHM) is widely used as a standard test species for acute and chronic toxicity testing of contaminants, effluents, and receiving waters. Because of its widespread distribution throughout North America, this species also has application in monitoring studies and for deployment using caged exposures in the field. However, the FHM has not been employed previously as a tool for determining the genetic toxic effects of chemicals or complex environmental mixtures. In the present study, fathead minnows were exposed to varying dose levels of the known mutagen, methyl methanesulfonate, either by a single intraperitoneal injection or by static renewal in water. DNA damage was evaluated in liver and blood cells at 1 and 3 days after the start of exposure using the single cell gel electrophoresis (SCGE) assay. Dose-related increases in DNA damage were observed in both blood and liver using either exposure regimen. The maximum levels of damage in treated fish exceeded control levels by more than 10-fold. Studies are underway to examine DNA damage in FHM following acute and chronic exposures to the pesticide atrazine, both alone and in combination with other chemicals. These results indicate the feasibility of evaluating DNA damage in tissues of fathead minnows, and suggest that the SCGE assay in this species could be a useful addition to standard aquatic toxicity test protocols and as an indicator method for assessing exposure to genotoxic agents in the field.

PRESENTATION Hyperspectral Remote Sensing of Water Quality Parameters for Large Rivers in the Ohio River Basin 11/05/2003
Shafique, N A., F A. Fulk, B C. Autrey, AND J E. Flotemersch. Hyperspectral Remote Sensing of Water Quality Parameters for Large Rivers in the Ohio River Basin. Presented at Ohio River Basin Consortium for Research and Education, Marietta, OH, November 5-7, 2003.
Abstract: Optical indicators of water quality have the potential of enhancing the abilities of resource managers to monitor water bodies in a timely and cost-effective manner. However, the degree to which optical indicators are useful may depend on their applicability to data collected from multiple water bodies. In 1999, a Compact Airborne Spectrographic Imager (CASI) was flown over the relatively shallow Great Miami River (GMR), Ohio, collecting hyperspectral bands of data. Concurrently, water quality parameters were measured, and water samples and spectrometer data were collected directly from the river. Using correlations between the ground-truth data and combinations of bands from the remotely sensed data, spectral indices were developed which could be used to estimate chlorophyll a, turbidity and phosphorus. In 2001, a similar study was conducted in which a CASI was flown over a portion of the relatively deep Ohio River while ground-truth data were collected. These data were analyzed and tested against the spectral indices developed during the 1999 study. The GMR's spectral index for chlorophyll a was applicable to the Ohio River data. However, slightly refined spectral indices for turbidity and phosphorus were required.
This study demonstrates the ubiquitous applicability of the chlorophyll a spectral index while revealing the limited applicability of the turbidity and phosphorous spectral indices. Although differences between the dynamics of the two rivers may have made these spectral indices incompatible, with further refinement they may yet prove to be broadly applicable tools in the detection and measurement of potential water quality problems.

PRESENTATION Ecological Genetics Research at the USEPA 11/05/2003
Bagley, M J. Ecological Genetics Research at the USEPA. Presented at Buffalo State College, Buffalo, NY, November 5, 2003.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION EPA: the Agency, the Public and the Science 10/29/2003
Fulk, F A. EPA: the Agency, the Public and the Science. Presented at 13th Annual Westheimer Peace Symposium, Wilmington, OH, October 29, 2003.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION Interregional Comparison of Nutrient Uptake Rates in Managed and Old-Growth Watersheds 10/28/2003
McCormick, F H. AND B H. Hill. Interregional Comparison of Nutrient Uptake Rates in Managed and Old-Growth Watersheds. Presented at Interagency Conference on Research in the Watersheds, Benson, AZ, October 28-30, 2003.
Abstract: We compared nutrient uptake rates to examine the effect of timber harvest on streams. From 1999-2002, nutrient additions were conducted in 50 stream reaches in 4 ecoregions (southern Blue Ridge, NC, Ouachita Mountains, AR, Cascade Mountains, OR, and the redwood forests of the Coast Range, CA). Nutrient uptake was measured, along with the Cl-tracer, by depletion over stream distance. Streams draining logged watersheds had smaller dominant substrate size, more open canopies, and more sand and fine sediments in the channel. Phosphate uptake lengths were not significantly different when comparing streams draining old-growth or harvested watersheds or ecoregions. Ammonium uptake lengths were significantly longer in old-growth compared to harvested watersheds but were not different among ecoregions.

PRESENTATION Identifying Causes of Biological Tmdls 10/15/2003
Cormier, S M., S B. Norton, AND G Suter. Identifying Causes of Biological Tmdls. Presented at Minnesota Pollution Control Agency Workshop, Hinkley, MN, October 14-16, 2003.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION A Comparison of Bulk Sediment Toxicity Testing Methods and Sediment Elutriate Toxicity 10/14/2003
Lazorchak, J M., M E. Smith, P. Crocker, A. Euresti, H Haring, AND M Bennett. A Comparison of Bulk Sediment Toxicity Testing Methods and Sediment Elutriate Toxicity. Presented at Biological Advisory Committee Meeting, Newport, RI, October 14-16, 2003.
Abstract: Bulk sediment toxicity tests are routinely used to assess the level and extent of contamination in natural sediments. While reliable, these tests can be resource intensive, requiring significant outlays of time and materials. The purpose of this study was to compare the results from bulk sediment toxicity tests using Hyalella azteca and Chironomus tentans to the results obtained from sediment elutriate tests using conventional Ceriodaphnia dubia and Pimephales promelas water column toxicity testing methods. The elutriate tests offer a considerable cost savings and may have broad application where sediment testing capacity is not possible. EPA Region 6, in cooperation with states and tribes, has been conducting sediment elutriate tests as part of a regional ambient toxicity testing program ("TOXNET"). In this project, the Region sought assistance from the Office of Research and Development through the Regional Methods Initiative (RMI) Program to conduct side-by-side tests for conventional bulk freshwater sediment and ASTM elutriate methods. The results of the project will aid in assessing the adequacy of current ambient toxicity monitoring.

PRESENTATION A Daphnia Magna Short-Term Survival and Growth Test 10/14/2003
Lazorchak, J M., M E. Smith, L. E. Herrin, AND M. E. Young. A Daphnia Magna Short-Term Survival and Growth Test. Presented at Biological Advisory Committee Meeting, Newport, RI, October 14-16, 2003.
Abstract: With the change in acceptable test temperatures for invertebrate toxicity tests from <20oC to 25oC, it is now possible to use Daphnia magna for short-term chronic testing. When cultured at 25oC the dry weight of <24 hr old D. magna ranges from 7 to 15 g depending upon nutrition, brood number and/or brood size. Within 48 hours such daphnids increase their dry weight to 40 to 60 ug and within 94 hrs can weigh 100 to 200 ug. This rate of increase in growth makes this organism very desirable for use in a short-term chronic method. The purpose of this study was to develop a 2 to 4 day D. magna short-term survival and growth test that was similar in sensitivity to the 7 day Ceriodaphnia dubia survival and reproduction test. The results thus far, using 3 reference toxicants, indicate that the difference in sensitivity for the two test methods is less than a dilution or factor of 2.

PRESENTATION Miniaturized Sediment Procedures for Assessing Toxicity Using Marine and Freshwater Amphipods and Embryo/Larval Fish 10/14/2003
Lazorchak, J M., M E. Smith, T. A. Hollister, J. A. Ferretti, AND D. F. Calesso. Miniaturized Sediment Procedures for Assessing Toxicity Using Marine and Freshwater Amphipods and Embryo/Larval Fish. Presented at Biological Advisory Committee Meeting, Newport, RI, October 14-16, 2003.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION Biosurvey/Bioassessment Protocols and Methods for Large Rivers and the Development of Biological Indicators 10/13/2003
Flotemersch, J E. Biosurvey/Bioassessment Protocols and Methods for Large Rivers and the Development of Biological Indicators. Presented at Biological Advisory Committee Meeting, Newport, RI, October 13 - 16, 2003.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION Development of Biological Indicators, Methods and Assessment Techniques in First Order and Intermittent Streams: Headwater Intermittent Streams Study 10/13/2003
FRITZ, K. M. Development of Biological Indicators, Methods and Assessment Techniques in First Order and Intermittent Streams: Headwater Intermittent Streams Study. Presented at Biological Advisory Committee Meeting, Newport, RI, October 13 - 16, 2006.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION Associations Between Genetic Diversity and Anthropogenic Disturbance in Midwestern Stream-Dwelling Minnows 08/11/2003
Bagley, M J., S E. Franson, AND S A. Christ. Associations Between Genetic Diversity and Anthropogenic Disturbance in Midwestern Stream-Dwelling Minnows. Presented at American Fisheries Society 2003 Annual Meeting, Quebec, Canada, August 9-15, 2003.
Abstract: Anthropogenic disturbances may leave imprints on patterns of intraspecific genetic diversity through their effects on population size, adaptation, migration, and mutation. We examined patterns of genetic diversity for a stream-dwelling minnow (the central stoneroller, Campostoma anomalum) in relation to several measures of environmental condition for populations residing in Ohio and Indiana, USA. Genetic differentiation among samples from 91 randomly selected first through third order streams was high. Genetic distance analyses suggested the existence of at least five major genetic lineages in this region. Average genetic diversity within sites, as measured by a similarity index, differed greatly among sites. Variables relating to stream habitat quality, geography, and contaminant exposure, were evaluated for their relationship to genetic diversity in a mixed model analysis, with stepwise elimination of least significant effects. Five effects were retained in the reduced model, which explained about half of within-site genetic diversity. Highly significant effects in the model included major genetic lineage and anthropogenic impact indicators for urbanization and riparian disturbance. Stream channelization and average stream depth at the sample site were also important. These results suggest anthropogenic disturbances can have strong influences on genetic diversity and may therefore influence the long-term sustainability of these populations.

PRESENTATION Effect of Urbanization on Fish Assemblages and Habitat Quality in a Piedmont River Basin 08/09/2003
WALTERS, DAVID M., M. C. Freeman, D. S. Leigh, B. J. Freeman, AND C. M. Pringle. Effect of Urbanization on Fish Assemblages and Habitat Quality in a Piedmont River Basin. Presented at American Fisheries Society 2003 Annual Meeting, Quebec City, QC, CANADA, August 09 - 15, 2003.
Abstract: We quantified the relationships among urbanization, fishes, and habitat quality to determine how assemblags respond to urbanization and if a habitat quality assessment reflects urban effects on stream ecosystems. We sampled 30 wadeable streams along an urban gradient in the Etowah River basin, Georgia. Fish assemblage composition was assessed as richness and abundance of key taxonomic groups and for endemic species as a group. Habitat quality was scored using the USEPA's Rapid Habitat Assessment Protocol (RHAP). After accounting for natural variation with basin area and slope, we found that richness and density, darters and sculpin, cyprinids, and endemic species declined with urbanization, whereas centrarchids persisted and became the dominant group. RHAP scores were correlated with fish assemblage structure, but RHAP was more related to local variation in stream slope than basin urbanization. Urban effects were strongest for centrarchids (increase) and endemics (decline), and these effects were greatest for streams with >15% urban cover. Most development in the region occurred since 1987, suggesting that fishes respond rapidly to urbanization. We predict that endemics and other species will continue to decline and that centrarchid-dominated streams will be common as urbanization increases within the basin.

PRESENTATION Electrofishing in Boatable Rivers: Does Sampling Design Affect Bioassessment Metrics? 08/09/2003
Flotemersch, J E. AND K A. Blocksom. Electrofishing in Boatable Rivers: Does Sampling Design Affect Bioassessment Metrics? Presented at American Fisheries Society 2003 Annual Meeting, Quebec, Canada, August 9-15, 2003.
Abstract: The accurate bioassessment of boatable rivers using fish assemblage data requires that a representative sample of the assemblage be collected. Data were collected using an electrofishing design that permitted comparisons of the effects of designs and distances on fish assemblage metrics. These fish and habitat data were collected from 60 boatable sites distributed among four rivers within the Ohio River Basin. Sites were classified a priori as either Run-of-the-River (ROR) or Restricted Flow (RF). At each site, one bank was electrofished to a distance of 40 times the wetted width, up to a maximum distance of 2000 m, and the opposite bank was electrofished to a distance of 1000 m. Fish were processed at up to 14 points during data collection. Data representing four different design options (i.e., 1000 and 2000 m for both single and paired banks) were extracted from the dataset and analyzed. A Principal Components Analysis (PCA) on physical habitat variables showed that depth was the most important variable in separating ROR and RF sites. Friedman tests comparing metric values among the four designs detected significant differences for all richness metrics at both types of sites and for CPUE and percent tolerant species at ROR sites. Richness metrics were generally higher for the two 2000-m designs than for the two 1000-m designs. When plotted against cumulative electrofishing distance, the percent change in metrics declined sharply within approximately 1000 m, after which metrics usually varied by less than 10%. These data demonstrate that designs electrofishing 1000 m of shoreline are sufficient for bioassessments on boatable rivers similar to those in this study, regardless of whether the shoreline is along a single bank or distributed equally among paired banks. However, at sites with depths > 4 m, it may be advisable to employ nighttime electrofishing or increase day electrofishing designs to 2000 m.

PRESENTATION Adaptive Responses of Upland and Coastal Marsh Plant Communities to Climate Change 08/05/2003
Blum, M, J. S. McLachlan, AND C. J. Saunders. Adaptive Responses of Upland and Coastal Marsh Plant Communities to Climate Change. Presented at Ecological Society of America, Savannah, GA, August 4-8, 2003.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION Nutrients, Canopy Cover, and Grazers: Their Effects on Summer Periphyton in Small Midwestern Streams 08/03/2003
Griffith, M. B., F B. Daniel, J M. Lazorchak, AND M E. Troyer. Nutrients, Canopy Cover, and Grazers: Their Effects on Summer Periphyton in Small Midwestern Streams. Presented at Ecological Society of America, Savannah, GA, August 3-8, 2003.
Abstract: Numerous studies in artificial streams suggest the relationship between nurients and periphyton biomass (AFDM) and chlorophyll a in streams is affected by ambient light, which is influenced by canopy cover, and by grazer densities. To assess the relationships between nutrients and eutrophication-type effects in small streams, we created a model to describe spatial and among year variations in periphyton collected duirng the summer of three years from 35 2nd-3rd order tributaries (Strahler order from RF3 digital maps) of the Little Miami River, Ohio. These streams are characterized by high concentrations of dissolved P (tdP, 0.026-0.30 mg L-1) and nitrate-N (0.016-14 mg L-1), agricultural land cover (row crop and grassland: 50-95%) and variable riparian canopies (6.3-93%). The basin also includes two ecoregions that differ in their relationships between land cover and nutrient inputs to streams. Grazer densities during the three years of study have ranged from 0.44-900 individuals m-2. Regression analysis showed that periphyton AFDM was positively related to tdP and inversely related to canopy density (decreasing light). Periphyton chlorophyll a was positively related to grazer density and nitrate-N, but relationship with nirate-N differed between the ecoregions. Grazer density was positively correlated with nitrate-N (r - 0.35, p<0.001), suggesting that grazers suppress the effects of nutrients and reduce the increase in periphyton accumulation as nutrient concentrations increase.

PRESENTATION No Reduction in Genetic Diversity Despite Rapid Adaptation in PCB Pollution: Implications for Conservation of Large Estuarine Populations 06/28/2003
McMillan, A., M J. Bagley, D Nacci, AND S A. Christ. No Reduction in Genetic Diversity Despite Rapid Adaptation in PCB Pollution: Implications for Conservation of Large Estuarine Populations. Presented at Society for Conservation Biology, Duluth, MN, June 28-July 2, 2003.
Abstract: Anthropogenic stressors can have negative fitness impacts on populations by reducing population size through direct mortality or reduced reproduction. Evolutionary consequences of pollutants are inevitable if genetic diversity and structure are changed as a result of these impacts. We evaluated the genetic structure and diversity of Fundulus heteroclitus, a non-migratory fish found in abundance in estuaries along the east coast of the U.S., including a PCB-contaminated superfund site in New Bedford Harbor (NBH), MA. Laboratory challenge experiments showed F. heteroclitus from NBH are adapted to high PCB levels while fish from uncontaminated sites are not. These results suggest that strong divergence has occurred in response to recent anthropogenic changes and has been maintained among populations with potentially high gene flow. We used AFLP analysis to determine whether genetic variability of tolerant F. heteroclitus populations in NBH is reduced relative to populations residing in less contaminated sites and to estimate the degree of genetic differentiation between populations with different sensitivities to PCBs. F. heteroclitus populations were differentiated at local scales but genetic diversity was not reduced in PCB adapted populations. Demographic factors, including large population sizes and high fecundity rates, appear to be the primary causes for these results.

PRESENTATION Biological and Physical Habitat Data 06/09/2003
Moeykens, M D. AND K A. Blocksom. Biological and Physical Habitat Data. Presented at Region V LIPS Midwest, Chicago, IL, June 9, 2003.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION Investigating Causes of Biological Impairments in Aquatic Systems: the Causal Analysis/Diagnosis Decision Information System 05/27/2003
Norton, S B., L E. Rao, S M. Cormier, G Suter, B. Swietlik, D. Norton, B. G. Brown, B Subramanian, AND K S. Minamyer. Investigating Causes of Biological Impairments in Aquatic Systems: the Causal Analysis/Diagnosis Decision Information System. Presented at North American Benthological Society, Athens, GA, May 27-31, 2003.
Abstract: Increasingly, the regulatory, remedial and restoration actions taken to manage impaired environments are based on measurement and analysis of the biotic community. When an aquatic community has been identified as impaired, the cause of the impairment must be determined so that appropriate actions can be taken. The USEPA's Stressor Identification (SI) Guidance describes a methodology for identifying the causes of observed impairments in aquatic systems. Stressor identification requires extensive knowledge on a variety of stressors as well as depth of knowledge on the mechanism, symptoms, and stressor-response relationships for specific stressors.
This poster describes results of a recent workshop on developing the Causal Analysis/Diagnosis Decision Information System (CADDIS). CADDIS is envisioned as a decision support system that will help investigators in the regions, states and tribes find, access, organize and share information useful for causal evaluations in aquatic systems. Workshop participants recommended that the system be developed incrementally and iteratively, and emphasized that frequent user input and feedback will be essential to the system's success. Functions identified for short-term development include a step-by-step guide to stressor identification, a knowledge base that would help users find and interpret relevant information, and assistance in organizing and reporting results.

PRESENTATION A Standardized Assessment Method (Sam) for Riverine Macroinvertebrates 05/27/2003
Blocksom, K A., J E. Flotemersch, AND J J. Hutchens. A Standardized Assessment Method (Sam) for Riverine Macroinvertebrates. Presented at North American Benthological Society, Athens, GA, May 27-31, 2003.
Abstract: A macroinvertebrate sampling method for large rivers based on desirable characteristics of existing nonwadeable methods was developed and tested. Six sites each were sampled on the Great Miami and Kentucky Rivers, reflecting a human disturbance gradient. Samples were collected from 12 transects at specific intervals totaling 40 times the wetted width of each site. Timed kick-net and dip-net samples were composited for each transect and bank. All organisms up to 2000 individuals were sorted from each sample. For analysis, data from successively longer distances were combined across banks, and 300-organism random subsamples were simulated 100 times per sample. Richness metrics leveled off within 500 m, and percentage metrics varied little with distance. We then simulated 100- to 800-organism subsamples from composite samples based on a 500-m sampling distance. Subsampling 300 organisms provided good site separation based on richness metrics, and percentage metric values were unaffected by subsample size. A 500-m sampling distance and a 300-organism subsample are recommended for the SAM for macroinvertebrates in these and similar large rivers. The SAM contains both systematic and subjective components that are complementary and represent the assemblage in a logistically efficient manner.

PRESENTATION Biology and Occurrence of the Leech, Actinobdella Inequiannulata (Annelida: Hirudinea: Glossiphoniidae) Parasitic on Two Species of Suckers 05/27/2003
Klemm, D J., B. A. Daniels, AND W. E. Moser. Biology and Occurrence of the Leech, Actinobdella Inequiannulata (Annelida: Hirudinea: Glossiphoniidae) Parasitic on Two Species of Suckers. Presented at North American Benthological Society, Athens, GA, May 27-31, 2003.
Abstract: Actinobdella inequiannulata was found on the white sucker, Catostomus commersoni, and less frequently on the longnose sucker, Catostomus catostomus, in Algonquin Provincial Park, Ontario, Canada. This study established the presence of only one species of leech, Actinobdela inequiannulata (Moore, 1901) parasitic on the white sucker, Catsotomus commersoni (Lacepede, 1803), and occasionally on the longnose sucker, Catostomus catostomus (Forster, 1773), and was also undertaken to determine the population dynamics of this leech species and its influence on fish community and health. In May and October, less than 3% of the fish carried leeches. In July, 80% of the fish were parasitized with an average of 1.5 leeches per fish. Observations on leech weight suggest young leeches attach to fish from May to September, some mature in July, and a second generation of leeches re-parasitize the fish in August and September. The mean size of leeches on suckers increased from May until July, after which size remained relatively constant. Leeches produced characteristic lesions on the opercula of suckers. Fully-developed lesions on fish opercula by aggregated leeches had varying amounts of central erosion, extravasation, dermal and epidermal hyperplasia, and necrosis.

PRESENTATION Harshness: Characterization of Intermittent Stream Habitat Over Space and Time 05/27/2003
Fritz, K M. AND W. K. Dodds. Harshness: Characterization of Intermittent Stream Habitat Over Space and Time. Presented at North American Benthological Society, Athens, GA, May 27-31, 2003.
Abstract: Frequently disturbed environments, such as intermittent streams, are ecologically useful for studying how disturbance characteristics (e.g., frequency, magnitude) affect community structure and succession. A harshness index summarizing spatial and temporal characteristics of prairie intermittent streams was developed to predict benthic macroinvertebrate assemblage measures. The index incorporates 11 variables that describe recent and historical hydrologic regime (e.g., average flow, flow variability, drying, and flooding) and surface water connectivity. Relationships between index values and annual assemblage characteristics (taxonomic richness, diversity, evenness, and abundance) were tested over 2 years using 7 sites across a range of flow permanence. Total macroinvertebrate abundance was significantly related to harshness values in both years, whereas taxonomic richness and species diversity were significantly related to harshness index values only for the year with lower flood frequency. The results suggest that temporal and spatial aspects of habitat harshness constrain community structure in intermittent streams. It is important to consider both short-term factors (e.g., floods, distance from colonization sources) that can alter abundance and colonization immediately, and historical factors (e.g., probability of drying, average duration of dry periods) that may be relevant over longer timescales.

PRESENTATION An Interregional Comparison of Channel Structure, Transient Storage and Nutrient Uptake in Streams Draining Managed and Old Growth Watersheds 05/27/2003
Hill, B H., F H. McCormick, B. C. Harvey, S. L. Johnson, AND M. C. Warren. An Interregional Comparison of Channel Structure, Transient Storage and Nutrient Uptake in Streams Draining Managed and Old Growth Watersheds. Presented at North American Benthological Society, Athens, GA, May 27-31, 2003.
Abstract: We compared stream channel structure (width, depth, substrate composition) and riparian canopy with transient storage and nutrient uptake in 32 streams draining old-growth and managed watersheds in the Appalachian Mountains (North Carolina), Ouachita Mountains (Arkansas), Cascade Range (Oregon) and coastal redwoods (California). Despite distinct stream differences among geographic regions, there were consistent trends in channel structure and riparian canopy in streams draining old-growth and managed watersheds. No significant differences were found in stream width, depth, or streambed area, but streams draining managed watersheds had less riparian and smaller median substrate sizes. Transient storage was calculated as the difference between predicted and actual chloride transport, and nutrient uptake was estimated from the downstream depletion of added nutrients. Transient storage (As) was greatest in the redwoods streams, followed by Cascade, Ouachita and Appalachian streams. In all regions, streams draining managed watersheds had less As than streams draining old-growth watersheds. Phosphate uptake did not exhibit strong regional or treatment differences, but was significantly longer where riparian canopy and As were greater. Ammonium uptake was significantly different among regions, longer in streams draining old-growth watershed, and inversely correlated with riparian canopy, channel area, and As.

PRESENTATION Intermittent Streams: Not Just a Dry Topic 05/26/2003
Fritz, K M. Intermittent Streams: Not Just a Dry Topic. Presented at North American Benthological Society, Athens, GA, May 26 - 31, 2003.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION EPA's Genetic Diversity Research Program: Ecological Indicator Development 05/15/2003
Franson, S E. EPA's Genetic Diversity Research Program: Ecological Indicator Development. Presented at Emerging Challenges for Environmental Science in the Ohio Valley Region, Cincinnati, OH, May 15, 2003.
Abstract: Genetic diversity is a fundamental component of biodiversity that is affected by environmental stressors in predictable ways and limits potential responses of a population to future stressors. Understanding patterns of genetic diversity enhances the value and interpretation of other ecological assessment data. This talk will provide a brief overview of some of the molecular methods used to measure genetic diversity, and their application in several of the research projects in EPA's genetic diversity program.

PRESENTATION Application of Molecular Tools to Ecological Questions 05/15/2003
Lattier, D L. Application of Molecular Tools to Ecological Questions. Presented at Society of Environmental Toxicology and Chemistry, 20th Annual Ohio Valley Chapter, Cincinnati, OH, May 14-15, 2003.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION Molecular Biology Methods 05/14/2003
Lattier, D L. Molecular Biology Methods. Presented at Society of Environmental Toxicology and Chemistry, 20th Annual Ohio Valley Chapter, Cincinnati, OH, May 14-15, 2003.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION Environmental Influences on Genetic Diversity of Creek Chubs in the Mid-Atlantic Region of the USA 05/13/2003
Christ, S A., M J. Bagley, AND F H. McCormick. Environmental Influences on Genetic Diversity of Creek Chubs in the Mid-Atlantic Region of the USA. Presented at Using Science to Assess Environmental Vulnerabilities: a ReVA/MAIA Conference, Valley Forge, PA, May 13-15, 2003.
Abstract: Analysis of genetic diversity within and among populations of stream fishes may provide a powerful method for assessing the status and trends in the condition of aquatic ecosystems. We analyzed mitochondrial DNA sequences (590 bases of cytochrome B) and nuclear DNA loci (109 amplified fragment length polymorphisms, AFLP) of creek chub (Semotilus atromaculatus) populations from ten sites located in coal mining regions of Pennsylvania and West Virginia. This study represents the first phase of a larger study that will assess genetic diversity of multiple fish species throughout EPA's Mid-Atlantic Assessment Area (MAIA). Creek chub were strongly genetically differentiated, as the among-population component of genetic variance explained 71% of all mitochondiral diversity and 13% of nuclear DNA diversity. Genetic diversity within populations was assessed in relation to six independent environmental factors derived by principal component analysis (PCA) of 25 aquatic variables measured at each site. A PCA factor related to total nitrogen, phosphorous, and organic carbon content explained 51% of differences in the levels of mitochondrial diversity within populations, based on forward stepwise multiple regression. Three PCA factors explained 98% of the differences in nuclear DNA diversity within populations. The three factors were associated with latitudinal clines (43%) nitrogen/phosphorous/carbon (35%) and pH/ammonium (18%). A PCA factor related to geochemistry, which accounted for the most environmental variation, was not significantly associated with genetic diversity. These results provide evidence that environmental factors can strongly influence genetic diversity within populations, thus impacting their future vulnerability to environmental stresses.

PRESENTATION Computational Toxicology in EPA's Office of Research and Development 05/08/2003
Toth, G P. Computational Toxicology in EPA's Office of Research and Development. Presented at NCEA Genomics Colloquium, Washington, DC, May 8, 2003.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION Genomics Research Applied to Issues in Ecological Risk Assessment 05/08/2003
Toth, G P. Genomics Research Applied to Issues in Ecological Risk Assessment. Presented at NCEA Genomics Colloquium, Washington, DC, May 8, 2003.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION Development of Dna Microarrays for Ecological Exposure Assessment 05/05/2003
Miracle, A L. AND D L. Lattier. Development of Dna Microarrays for Ecological Exposure Assessment. Presented at Science Forum 2003, Washington, DC, May 5-7, 2003.
Abstract: EPA/ORD is moving forward with a computational toxicology initiative in FY 04 which aims to integrate genomics and computational methods to provide a mechanistic basis for prediction of exposure and effects of chemical stressors in the environment.
The goal of the present research is to develop a genomic screening tool (DNA microarrays) for identification of unique patterns of genes that are "turned on" or "turned off" by specific environmental stressors. DNA microarrays are made with hundreds to ten thousands of gene sequences arrayed in a manner conducive for rapid screening of a large number of genes at one time. Until recently, microarray production was limited to organisms in which sequence information was known, such as human or mouse. Through a variety of modern molecular biological techniques, hundreds of genes from a standard aquatic organism used extensively in toxicity testing (e.g., the fathead minnow, Pimephales promelas) are now known. The ongoing effort to build a gene sequence database for the fathead minnow will soon result in the ability to assess changes in gene expression as a result of an aquatic environmental exposure. More importantly, the examination of patterns of gene expression changes resulting from environmental mixtures (multiple stressors) can be rapidly assessed using this type of molecular platform, and compared to single stressor patterns. Signatures of gene expression for specific stressors will then be used to develop specific, diagnostic exposure indicators, which is a vital component in the development of non-invasive computational models for toxicological risk assessment. In partnership with other ORD labs, a better understanding of the pathways from exposure to outcome can be achieved for building computational toxicology. This technology will ultimately reduce the uncertainty in assessing risk of stressors in the environment.

PRESENTATION Indicators of Risk: An Analysis Approach for Improved River Management 05/05/2003
Autrey, B C., R. B. Benjamin, F A. Fulk, J E. Flotemersch, AND K A. Blocksom. Indicators of Risk: An Analysis Approach for Improved River Management. Presented at Science Forum 2003, Washington, DC, May 5-7, 2003.
Abstract: A risk index is an approach to measuring the level of risk to the plants and/or animals (biota) in a certain area using water and habitat quality information. A new technique for developing risk indices was applied to data collected from Mid-Atlantic streams of the U.S. during 1997 and 1998 because the assumptions required by traditional methods of statistical analysis were not met. Specifically, water and habitat quality data were used to develop risk indices for the invertebrates (animals such as insects, mussels, worms and snails) in these streams. Multiple habitat and water quality measurements were used as predictors of measurements of invertebrates (responses) such as the number of species present or the diversity of invertebrates. Potential predictor and response variables were ranked and sorted. The top 1/3 of the values were placed into the "high" category, the middle 1/3 were placed into the "moderate" category and the bottom 1/3 were placed into the "low" category. Using a step-wise discriminant analysis (a statistical method for determining which measurements are best able to discriminate among groups) followed by Chi-Square tests (a statistical method for determining if the observed distribution of measurements is significantly different from the expected distribution), a set of good (discriminating) predictors were chosen for each response variable. Then, a Maximum Response Profile (MRP) was defined for each response variable. The MRP is the combination of the categories (high, moderate or low) of the discriminant predictors that most frequently results in the response being in the most desirable category (indicating good biological condition). A Risk Index (RI) was then calculated for each response measurement at each sampling location. Each RI was the total number of discriminant predictors at each location that did not fall into the MRP. High RI values were consistently associated with response measurements in the least desirable category (indicating poor biological condition). This analysis approach may help resource managers to better understand the water and habitat quality problems most adversely affecting the biota in their streams, thereby equipping them better to manage these systems.

PRESENTATION The Evolution of Resistance to Plant Incorporated Protectants By Targeted Insect Pests 05/05/2003
Stolz, U, M Blum, AND M J. Bagley. The Evolution of Resistance to Plant Incorporated Protectants By Targeted Insect Pests. Presented at Science Forum 2003, Washington, DC, May 5-7, 2003.
Abstract: Genetically modified (GM) crops, also known as transgenic crops, offer potential economic, environmental, and human health benefits. Balanced against these potential benefits are several possible liabilities, one of which is environmental harm. The EPA must fulfill its mandate to assess the environmental risks of (GM) crops based on the best available information. However, there is limited information available to make meaningful decisions about long-term environmental risks of GM crops. It is important that the EPA continue to ascertain long-term ecological risks and identify the types of new data that are required for the most accurate risk assessment possible. One important long-term risk is adaptation by targeted pests to plant-incorporated protectants (PIPs) such as insecticidal Bt proteins. Bt crops provide direct economic benefits to farmers and may provide human health and environmental benefits by decreasing the use of toxic pesticides normally used to control pest outbreaks. Insect resistance evolution to Bt crops would eliminate the benefits of PIP-expressing GM crops and require the use of traditional pesticides to control insect pests. Therefore, one important goal of the EPA is to delay the onset of resistance evolution and prolong the efficacy of PIPs. Additional information is required to evaluate the assumptions of models used to develop the agency's required strategy for insect resistance management (i.e., high dose, structured refuge) for different species and traits. Also, molecular screening for PIP-resistance in populations would allow early warning of potential outbreaks of resistant pest populations. Predicting the likelihood and rate of adaptation (i.e., evolution of PIP resistance) by targeted pests depends on a number of factors which are complex and poorly understood for most species. We will first examine the population genetics of a pest species to determine the amount of migration between different pest locations/populations and the levels of genetic variation in the wild. This information will be used to improve models of pest adaptation by adding actual field data into the models. We will also design PCR assays for detecting resistance in the field and evaluate this approach as an early warning system for detecting the evolution of resistance by the target pest. These results will provide the EPA Office of Pesticide Programs and Regional Offices with critical biological field data regarding insect resistance management/monitoring and will further the ultimate goal of decreasing the likelihood of resistance evolution by insect pests.

PRESENTATION Assessing Possible Ecological Risks of Genetically Modified Crops: Gene Expression Assays and Genetic Monitoring of Non-Target Organisms 05/05/2003
Blum, M, U Stolz, AND M J. Bagley. Assessing Possible Ecological Risks of Genetically Modified Crops: Gene Expression Assays and Genetic Monitoring of Non-Target Organisms. Presented at Science Forum 2003, Washington, DC, May 5-7, 2003.
Abstract: Widespread planting of genetically modified crops with the Bt transgene pesticide has led to concern over non-target effects of Bt compounds in agroecosystems. While some research suggests that non-target organisms exposed to Bt toxin exhibit reduced fecundity and increased mortality, other studies suggest that exposure has little or no effect on non-target organisms. The US EPA is therefore investing in research to better understand the potential risks that Bt crops may pose to non-target organisms. Indicator species will first be identified for non-target exposure monitoring in and around Bt-corn and Bt-cotton agroecosystems. Gene expression assays will subsequently be developed to assess exposure of non-target indicator organisms to Bt toxins. These assays will be employed to screen individuals for exposure to Bt toxins, while additional genetic monitoring will be done to establish population level responses to Bt exposure. Baseline studies of the population genetic structure of non-target indicator species inside and outside of areas planted with Bt crops will provide essential information on migration, genetic diversity, and effective population sizes. Further monitoring of indicator species over time will help establish whether localized Bt exposure influences the long-term viability of non-target populations. A combination of gene expression assays and population genetic monitoring will provide a comprehensive approach for evaluating how non-target Bt exposure may affect individual, population and ultimately, ecosystem health. Adapting this research to provide field monitoring tools will offer the U.S. E.P.A. Office of Pesticide Programs methods for tracking and mitigating potential non-target effects of Bt crops.

PRESENTATION Measures of Genetic Diversity Are Effective Tools for Evaluating Environmental Condition 05/05/2003
Bagley, M J., S A. Christ, S E. Franson, AND E R. Waits. Measures of Genetic Diversity Are Effective Tools for Evaluating Environmental Condition. Presented at Science Forum 2003, Washington, DC, May 5-7, 2003.
Abstract: At their core, ecological risk assessments aim to evaluate the biological integrity and long-term sustainability of natural ecosystems. These are difficult objectives that will ultimately require development of novel indicators of ecological condition that are more accurate and more efficient than those currently available. The US EPA has invested in a research program to develop efficient measures of genetic diversity within aquatic species that more directly address the biological integrity and sustainability of aquatic communities. These measures bring new and powerful information to our understanding of aquatic ecosystems, including the identification of appropriate ecological assessment units, the linkages between environmental condition and population responses, and estimates of the future susceptibility of populations due to loss of genetic diversity. The utility of genetic diversity measures as indicators of ecological condition is being evaluated through a number of independent studies that range in scale from watershed-level assessments to large regional surveys. At the watershed level, DNA from historical fish tissue archives have been tapped to evaluate changes in genetic diversity over time in experimentally manipulated lake systems and in a polluted urban stream. At larger scales, genetic diversity measures have been incorporated into regional assessments of a midwestern ecoregion and the EPA's Mid-Atlantic Integrated Assessment area. Results to date have indicated a close relationship between levels of genetic diversity in fish populations and measures of overall habitat quality. A new study aims to tie genetic data with landscape-level assessments and fish population modeling efforts to perform a truly integrated assessment of trends in condition of aquatic resources. Partnerships with other labs and agencies have been fundamental to this effort; significant collaborators include the Canadian Department of Fisheries and Oceans, the Ohio EPA, and various US EPA laboratories, including the Atlantic Ecology Division of ORD/NHEERL, and the Ecosystems Research Division and Environmental Science Division of ORD/NERL. Ultimately, the approach will provide State and USEPA Regions with a powerful tool to assess ecological condition and relative vulnerability of aquatic resources, thereby enhancing our ability to maintain and restore the integrity of the Nation's waterways.

PRESENTATION Streams to Rivers: the Next Generation of Ecosystem Monitoring 05/05/2003
Flotemersch, J E., K Fritz, K A. Blocksom, P. Nolan, AND M. Passmore. Streams to Rivers: the Next Generation of Ecosystem Monitoring. Presented at Science Forum 2003, Washington, DC, May 5-7, 2003.
Abstract: The historical focus in aquatic ecosystems has been on sampling methods oriented toward surveys of wadeable streams or smaller rivers. However, to fully assess the condition of the nations waters, methods are needed for systems above and below this scale. Biological communities change with stream size, as does habitat type and quality. This creates a need for assessors to have available clear and consistent methods for measuring community health that are specifically designed for these ecosystems. Through the Office of Research and Development's Regional Methods Initiative (RMI) program, NERL is currently engaged in collaborative research efforts with Regional Scientists to develop methods for the assessment of aquatic ecosystems for which standardized methods are lacking. The two major areas of focus are intermittent streams and large rivers, which together comprise > 60% of the total stream miles in the United States. NERL and Regional partnerships are delivering the next-generation of critically needed environmental monitoring tools. Cost effective methods that maximize the investment to result ratio, yet are logistically feasible, and with a scientific foundation that is defensible.

PRESENTATION Proposed Water Quality Surveillance Network Using Physical, Chemical and Biological Early Warning Systems (Bews) 05/05/2003
Lazorchak, J M., H. J. Allen, R Haught, D L. Lattier, AND J A. Goodrich. Proposed Water Quality Surveillance Network Using Physical, Chemical and Biological Early Warning Systems (Bews). Presented at Science Forum 2003, Washington, DC, May 5-7, 2003.
Abstract: The Homeland Protection Act of 2002 specifically calls for the investigation and use of Early Warning Systems (EWS) for water security reasons. The EWS is a screening tool for detecting changes in source water and distribution system water quality. A suite of time-relevant biological and physical/chemical water quality monitors applied in an EWS can provide timely information to aid decision-makers in the management and protection of the nation's water resources and measure the success of water quality control programs implemented under the Clean Water Act. A suite of monitors is necessary because no single organism will be sensitive to all contaminants at relevant concentrations. Current biological water quality monitors use fish, bivalves, arthropods, and bacteria and are capable of detecting contaminants at relatively short time periods (hours). Strategic placement of water quality monitors at both source water and distribution system locations of high vulnerability, likely targets, and control points may detect the presence of unsuspected chemicals or toxic interactions occurring as a result of spills, legal or illegal discharges, or intentional introductions. This work couples the "Canary in the coal mine" approach with the latest in behavioral, physiological, and physical/chemical monitoring techniques and current computing and communications equipment, to provide time-relevant data over a range of spatial scales (e.g., watersheds or regions). Because responses are sometimes caused by variations in water quality parameters (e.g., temperature, dissolved oxygen, or conductivity), selected physical and chemical parameters should be monitored simultaneously to facilitate interpretation of EWS data.
Many organizations in Europe currently use biomonitoring (BEWS) to monitor water supplies. The Molecular Ecology Research Branch (NERL) and the Water Quality Management Branch (NRMRL) propose to go beyond the European approach by investigating the use of a combination of advanced technologies that are time-relevant whole organism and molecular biosensing methods. Ultimately, we envision setting up a continuous, time-relevant national water quality surveillance network in all major rivers in the U.S. that are used for water supplies and their distributions systems. We plan to test the approach using Cincinnati, OH, as a model, with an EWS in the source water, Ohio River, and within the City's drinking water distribution system. Complimenting these whole organism systems will be molecular measures on fish and invertebrates using near-Real-time PCR methods for measuring - gene expression and microarray technologies. A model data collection, storage, and analysis infrastructure will be created to collate and analyze data from the EWS for detection and tracking of water quality events.

PRESENTATION Analyzing Water Quality With Images Acquired from Airborne Sensors 05/05/2003
Autrey, B C. Analyzing Water Quality With Images Acquired from Airborne Sensors. Presented at Science Forum 2003, Washington, DC, May 5-7, 2003.
Abstract: Monitoring different parameters of water quality can be a time consuming and expensive activity. However, the use of airborne light-sensitive (optical) instruments may enhance the abilities of resource managers to monitor water quality in rivers in a timely and cost-effective manner. The degree to which these optical instruments are useful will depend on their ability to detect water quality parameters in different water bodies. In 1999, an optical sensor was flown over the relatively shallow Great Miami River (GMR), Ohio, collecting an image consisting of many very narrow wavelengths of light (hyperspectral data). At the same time, water quality parameters were measured, water samples were collected and a spectrometer (another optical instrument) was used to collect data directly from the river. By using the relationships between the data collected directly from the river and the optical data collected from the airplane, mathematical relationships (called spectral indices) were developed which could be used to estimate the concentration of chlorophyll a, turbidity and the concentration of phosphorus in the river. In 2001, a similar study was conducted in which another hyperspectral imaging sensor was flown over a portion of the relatively deep Ohio River while other data were collected directly from the river. These data were analyzed and tested against the spectral indices developed during the 1999 study. The GMR's spectral index for chlorophyll a was usable in the Ohio River. However, the spectral indices developed from the GMR data for turbidity and phosphorous were not usable for the Ohio River data and, therefore, were refined in order to accurately estimate these parameters.
This study demonstrates the potentially widespread applicability of the chlorophyll a spectral index while revealing the limited applicability of the turbidity and phosphorous spectral indices. Although differences between the dynamics of the two rivers may have made these spectral indices incompatible, with further refinement they may yet prove to be broadly applicable tools in the detection and measurement of potential water quality problems. The full development of this tool will be the use of these indices in estimating water quality parameters with data acquired by satellite, and can help make water quality monitoring much more efficient for resource managers.

PRESENTATION What Degraded This Stream? Tools to Determine the Causes of Ecological Impairment 05/05/2003
Cormier, S M., B Subramanian, B C. Autrey, G Suter, S B. Norton, AND L E. Rao. What Degraded This Stream? Tools to Determine the Causes of Ecological Impairment. Presented at Science Forum 2003, Washington, DC, May 5-7, 2003.
Abstract: The identification of causes of impairment for waterbodies listed as biologically impaired is required as part of many federal, state and tribal regulations. The Office of Research and Development is developing a suite of tools that facilitates the identification and characterization of the probable causes of biological impairments, primarily in aquatic systems. The research includes the development and updates to the Stressor Identification Guidance, the production of state and tribal case studies of individual aquatic systems, the formation of databases of evidence, and the development of the CADDIS (Causal Assessment and Diagnosis Decision Information System). Channels for transfer of technical information include peer reviewed publication and training opportunities coordinated with the Office of Water, such as the recent National Bioassessment and Biocriteria Workshop and the Watershed Academy website training program. The methods and guidance developed in this program will provide EPA-OW, Regions, States and Tribes with tools to determine the causes of biological impairment in streams and rivers, putting us on a sound road to effective protection and restoration.

PRESENTATION Preliminary Year 2001 Gene Expression Findings 04/07/2003
Lazorchak, J M., R Flick, D L. Lattier, B E. Wiechman, M E. Smith, AND D A. Gordon. Preliminary Year 2001 Gene Expression Findings. Presented at Collaborators on Experimental Lakes Area Annual Meeging, Winnipeg, Canada, April 7-8, 2003.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION Fish Methods for Sampling Large Rivers 03/31/2003
Flotemersch, J E. Fish Methods for Sampling Large Rivers. Presented at National Biological Assessment and Criteria Workshop, Coeur d'Alene, ID, March 31 - April 04, 2003.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION Biological Response Indicators of Riverine Ecosystem Quality 03/31/2003
Flotemersch, J E. Biological Response Indicators of Riverine Ecosystem Quality. Presented at National Biological Assessment and Criteria Workshop, Coeur d'Alene, ID, March 31 - April 04, 2003.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION Biological Index Development Methods: Selection of Metrics for Index Assembly 03/31/2003
Blocksom, K A. Biological Index Development Methods: Selection of Metrics for Index Assembly. Presented at National Biological Assessment and Criteria Workshop, Coeur d'Alene, ID, March 31-April 4, 2003.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION Water Chemistry in Large Rivers 03/31/2003
Flotemersch, J E. Water Chemistry in Large Rivers. Presented at National Biological Assessment and Criteria Workshop, Coeur d'Alene, ID, March 31 - April 04, 2003.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION Biological Index Development Methods: Applications 03/31/2003
Blocksom, K A., S M. Cormier, M. McIntyre, J. Gerritsen, R. Frydenborg, AND C. Hawkins. Biological Index Development Methods: Applications. Presented at National Biological Assessment and Criteria Workshop, Coeur d'Alene, ID, March 31-April 4, 2003.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION Algal Methods for Sampling Large Rivers 03/31/2003
Flotemersch, J E. Algal Methods for Sampling Large Rivers. Presented at National Biological Assessment and Criteria Workshop, Coeur d'Alene, ID, March 31 - April 04, 2003.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION Proposed Standardized Assessment Methods (Sams) for Electrofishing Large Rivers 03/31/2003
Flotemersch, J E. AND K A. Blocksom. Proposed Standardized Assessment Methods (Sams) for Electrofishing Large Rivers. Presented at National Biological Assessment and Criteria Workshop, Couer d'Alene, ID, March 31 - April 04, 2003.
Abstract: The effects of electrofishing design and sampling distance were studied at 49 sites across four boatable rivers ranging in drainage area from 13,947 to 23,041 km2 in the Ohio River basin. Two general types of sites were sampled: Run-of-the-River (Free-flowing sites or with small low-head dams that store rather than regulate waters) and Restricted Flow Sites (heavily influenced by navigational Lock and Dam structures built to support commercial traffic). Principal Components Analysis using habitat variables validated this classification of sites. The electrofishing design used for the study permitted the concomitant evaluation of multiple fine-scale bioassessment electrofishing design scenarios and the determination of the effect of distance on metric scores. We conclude from this study that the degree of impoundment of a river plays a critical role in characterizing sites and that different sampling methods or assessment techniques will be required to adequately describe different categories of systems. At Run-of-the-River sites, a daytime main-channel-border electrofishing design that electrofished 1000 m on one bank or 500 meters on paired-banks was effective and efficient at characterizing the study sites based on the metrics tested. At Restricted Flow sites, we suggest a switch from day to night electrofishing be considered. If night electrofishing is not feasible, we suggest increasing the electrofishing distance at these sites to a 1000-m paired-banks design or a 2000 m single-bank design. In addition to an increased distance, metrics based on fish species prone to diel movement should be interpreted with caution in Restricted Flow rivers. These results apply for rivers of this size in this region, but could likely be applied elsewhere in the absence of similar research.

PRESENTATION The Stressor Identification (Si) Process: Case Study 03/31/2003
Cormier, S M. The Stressor Identification (Si) Process: Case Study. Presented at National Biological Assessment and Criteria Workshop, Coeur d'Alene, ID, March 31-April 4, 2003.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION Benthic Macroinvertebrate Methods for Sampling Large Rivers 03/31/2003
Flotemersch, J E. Benthic Macroinvertebrate Methods for Sampling Large Rivers. Presented at National Biological Assessment and Criteria Workshop, Coeur d'Alene, ID, March 31 - April 04, 2003.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION The Stressor Identification (Si) Process: Si 101 03/31/2003
Cormier, S M. The Stressor Identification (Si) Process: Si 101. Presented at National Biological Assessment and Criteria Workshop, Coeur d'Alene, ID, March 31-April 4, 2003.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION Logistics and Safety on Large Rivers 03/31/2003
Flotemersch, J E. Logistics and Safety on Large Rivers. Presented at National Biological Assessment and Criteria Workshop, Coeur d'Alene, ID, March 31 - April 04, 2003.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION Large River Biological Assessment Methods, Introduction 03/31/2003
Flotemersch, J E. Large River Biological Assessment Methods, Introduction. Presented at National Biological Assessment and Criteria Workshop, Coeur d'Alene, ID, March 31 - April 04, 2003.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION The Development of a Repeatable and Objective Method for Deriving Pollution Tolerance Values 03/27/2003
Winters, L A., B C. Autrey, K A. Blocksom, J E. Flotemersch, AND F A. Fulk. The Development of a Repeatable and Objective Method for Deriving Pollution Tolerance Values. Presented at Mid-Atlantic Water Pollution Biology Workshop, Berkeley Springs, WV, March 27-28, 2003.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION What Is a Large River? 03/27/2003
Flotemersch, J E. What Is a Large River? Presented at Mid-Atlantic Water Pollution Biology Workshop, Berkeley Springs, WV, March 27-28, 2003.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION Water Chemistry Sampling in Large Rivers 03/27/2003
Flotemersch, J E. Water Chemistry Sampling in Large Rivers. Presented at Mid-Atlantic Water Pollution Biology Workshop, Berkeley Springs, WV, March 27 - 28, 2003.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION The Influence of Impoundment Status and Collection Method on Algal Assemblage Bioassessment in Large Rivers 03/27/2003
DeCelles, S, K A. Blocksom, AND J E. Flotemersch. The Influence of Impoundment Status and Collection Method on Algal Assemblage Bioassessment in Large Rivers. Presented at Mid-Atlantic Water Pollution Biology Workshop, Berkeley Springs, WV, March 27-28, 2003.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION Adapting Microarray Technology for Use in Ecotoxicogenomics 03/19/2003
Miracle, A L., D L. Lattier, R Flick, T V. Reddy, AND G P. Toth. Adapting Microarray Technology for Use in Ecotoxicogenomics. Presented at Third International Conference on Pharmaceuticals and Endocrine Disrupting Chemicals, Minneapolis, MN, March 19-21, 2003.
Abstract: Ecotoxicogenomics includes research to identify differential gene expression in laboratory and field animals exposed to toxicants, and ultimately, to link the earliest indicators of exposure to adverse effects in organisms and populations. The USEPA National Exposure Research Laboratory has started to develop a multiple aquatic stressor diagnostic exposure model using fathead minnow (Pimephales promelas) gene sequences in a microarray platform. Because there is very little gene sequence information for the target organism, an approach involving several different methodologies has been developed to examine specific gene expression and to identify stressor-specific patterns of expression over a portion of the expressed genome. Single exposure-specific subtractive cDNA libraries were constructed from adult liver, fry, and embryos to identify differentially expressed genes in minnows exposed to low levels of endocrine disruptor compounds. To complement genes isolated in subtractive arrays, other P. promelas gene sequences were identified by differential display PCR to isolate EDC sensitive genes. In addition, PCR primers based on close relatives of the fathead minnow, the common carp and goldfish, were used to identify homologs of known carp or goldfish genes. By combining these methods for identifying fathead minnow specific sequences, different functional classes of protein-encoding genes are used to build an oligo microarray that encompasses a sampling of the expressed genome. Single and multiple exposures are assessed at the oligo microarray level to gain a better understanding of relative bioavailability of environmental stressors present in mixtures. Thus, the use of microarray technology to examine gene expression promises to be a powerful tool in understanding environmental exposures and their impacts.

PRESENTATION Using Genomics to Examine Environmental Exposure in the Fathead Minnow 03/19/2003
Miracle, A L. AND D L. Lattier. Using Genomics to Examine Environmental Exposure in the Fathead Minnow. Presented at ORD Emerging Issues Seminar on Genomics, Seattle, WA, March 19, 2003.
Abstract: There is no abstract available for this product. If further information is requested, please refer to the bibliographic citation and contact the person listed under Contact field.

PRESENTATION Gene Expression Profiling Provides a Sensitive Measure of Exposure to 17-a Ethinylestradiol in the Fathead Minnow, Pimephales Promelas 03/09/2003
Miracle, A L., D L. Lattier, B. Aronow, C. Tomlinson, AND G P. Toth. Gene Expression Profiling Provides a Sensitive Measure of Exposure to 17-a Ethinylestradiol in the Fathead Minnow, Pimephales Promelas. Presented at Society of Toxicology, Salt Lake City, UT, March 9-13, 2003.
Abstract: The freshwater fish, the fathead minnow (Pimephales promelas) represents an outstanding biological indicator response model organism based on its ubiquitous North American distribution and extensive use in acute and chronic testing of contaminants, effluents and receiving waters. We hypothesize that tissue-specific gene expression patterns in the fathead minnow may provide a sensitive measure of an individual animal's exposure and response to environmental agents. Variation in gene expression patterns are likely to occur among different individuals within the same population, between life stages, and with different temporal exposures and concentration(s) of stressor(s). We have initially developed a low-density cDNA microarray composed of gene products differentially expressed in response to a 24 hour exposure of 5 ng/L 17-a ethinylestradiol within the liver of the male fathead minnow. To examine the differences in individual variation, life stage, and dose concentration, we screened the array with samples derived from the exposure of individuals to different combinations of these 3 variables. Our data suggest that gene expression profiling will provide a sensitive measure of response to environmental estrogen in the presence of developmental stage and inter-individual variations.

PUBLISHED REPORT Genetic Diversity as An Indicator of Ecosystem Condition and Sustainability: Utility for Regional Assessments of Stream Condition in the Eastern United States 11/01/2003
Bagley, M J., S E. Franson, S A. Christ, E R. Waits, AND G P. Toth. Genetic Diversity as An Indicator of Ecosystem Condition and Sustainability: Utility for Regional Assessments of Stream Condition in the Eastern United States. U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-03/056 (NTIS PB2004107063), 2003.
Abstract: This report documents research undertaken to determine if the theoretical promise of genetic diversity as an ecological indicator is realized in real-world applications. Results of two case studies confirm that genetic diversity is a useful indicator of environmental condition. The first case study incorporated the genetic diversity indicator in a larger Regional Environmental Monitoring and Assessment Program study of the Eastern Cornbelt Plains Ecoregion, done in collaboration with USEPA Region 5 and Ohio EPA. Genetic diversity of a small cyprinid minnow, the central stoneroller (Campostoma anomalum) was measured at 91 sites in nine watersheds using the RAPD (random amplified polymorphic DNA) fingerprinting technique. The second case study examined the genetic diviersity indicator applied to populations of the creek chub (Semotilus atromaculatus) in a small region of western Pennsylvania and West Virginia underlain by coal-bearing geology and for which the history of coal mining operations is known. Samples of between 9 and 28 creek chubs were collected from 10 sites within 4 watersheds. Two molecular methods were used: the amplified fragment length polymorphism (AFLP) fingerprinting technique was used to assess diversity in the nuclear genome, while a portion of the mitochondrial genome was assessed using DNA sequencing. These two case studies clearly demonstrate that genetic diversity can serve as an indicator of environmental condition. They also provided the practical experience upon which recommendations for future implementation are based.

PUBLISHED REPORT A Comparison of Benthic Macroinvertebrate Sampling Methods for Non-Wadeable Riverine Ecosystems 09/30/2003
Flotemersch, J E., K A. Blocksom, AND B C. Autrey. A Comparison of Benthic Macroinvertebrate Sampling Methods for Non-Wadeable Riverine Ecosystems. U.S. Environmental Protection Agency, Washington, D.C., EPA/600/R-06/055 (NTIS PB2007-103757), 2003.
Abstract: Bioassessment of non-wadeable streams in the U.S. is becoming more common, but methods for these systems are not as well developed as for wadeable streams. This problem was recognized by the U.S. Environmental Protection Agency (EPA) regional scientists as critical to their monitoring and enforcement activities and, through the Office of Science Policy's Regional Methods (RM) program, funding for a research initiative was awarded to the National Exposure Research Laboratory, Ecological Exposure Research Division, Cincinnati, Ohio. The funding was provided to support the investigation of existing sampling methods for the bioassessment and monitoring of non-wadeable rivers and the development of new methods where needed.
We compared six benthic macroinvertebrate field sampling methods for non-wadeable rivers, two adapted from those used by each of three major programs: the Environmental Monitoring and Assessment Program-Surface Waters (EMAP-SW) of the USEPA, the National Water Quality Assessment Program (NAWQA) of the U.S. Geological Survey (USGS), and the Division of Surface Water Biocriteria Program of the Ohio EPA. We performed all six methods at a total of sixty sites across four tributaries to the Ohio River. Methods varied greatly with respect to the equiment used, the mesh sizes of equipment, and the key characteristics of the sampling technique, ranging from qualitative to quantitative, from passive to active, and from subjective to systematic. In addition to macroinvertebrate samples, water chemistry and physical habitat data were collected at each site to assess relationships between macroinvertebrate metrics and abiotic site condition. A single protocol was used to collect water chemistry samples and the EMAP-SW protocol was used to collect habitat data.

Sites were divided into two classes based on flow regimes: those influenced by navigational lock and dam structures built to support commercial traffic (i.e., restricted flow, or RF) and those free-flowing or having only low-head dams (i.e., run-of-the-river, or ROR).

 

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