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Ecological Exposure Research Division Publications: 2008

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This page lists publication titles, citations and abstracts produced by NERL's Ecological Exposure Research Division for the year 2008, organized by Publication Type. Your search has returned 55 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
JOURNAL Global Population Genetic Structure of the Starlet Anemone Nematostella Vectensis: Multiple Introductions and Implications for Conservation Policy 12/25/2008
Reitzel, A. M., J. DARLING, J. C. Sullivan, AND J. R. Finnerty. Global Population Genetic Structure of the Starlet Anemone Nematostella Vectensis: Multiple Introductions and Implications for Conservation Policy. BIOLOGICAL INVASIONS. Springer Science+Business Media, 10(8):1197-1213, (2008).
Abstract: Distinguishing natural versus anthropogenic dispersal of organisms is essential for determining the native range of a species and implementing an effective conservation strategy. For cryptogenic species with limited historical records, molecular data can help to identify introductions. Nematostella vectensis is a small, burrowing estuarine sea anemone found in tidally retricted salt marsh pools. This species' current distribution extends over three coast lines: the Atlantic coast of North America from Nova Scotia to Georgia; the Pacific coast of North America from Washington to central California; and the southeast coast of England. The 1996 IUCN red List designates N. vectensis as "vulnerable" in England. Amplified fragment length polymorphism (AFLP) fingerprinting of 516 individuals from 24 N. vectensis populations throughout its range and mtDNA sequencing of a subsample of these individuals strongly suggest that anthropogenic dispersal has played a significant role in its current distribution. Certain western Atlantic populations of N. vectensis exhibit greater genetic similarity to Pacific populations or English populations than to other western Atlantic populations. At the same time, F-statistics showing high degrees of genetic differentiation between geographically proximate populations support a low likelihood for natural dispersal between salt marshes. Furthermore, the western Atlantic harbors greater genetic diversity than either England or the eastern Pacific. Collectively, these data clearly imply that N. vectensis is native to the Atlantic coast of North America and that populations along the Pacific coast and in England are cases of successful introduction.

JOURNAL Genetic Patterns Across Multiple Introductions of the Globally Invasive Crab Genus Carcinus 12/01/2008
DARLING, J., M. BAGLEY, J. Roman, AND C. K. Tepolt. Genetic Patterns Across Multiple Introductions of the Globally Invasive Crab Genus Carcinus. MOLECULAR ECOLOGY. Blackwell Publishing, Malden, MA, 17(23):4992-5007, (2008).
Abstract: The European green crab Carcinus maenas is one of the world's most successful aquatic invaders, having established populations on every continent with temperate shores. Here we describe patterns of genetic diversity across both the native and introduced ranges of C. maenas and its sister species, C. aestuarii, including all known non-native populations. The global data set includes sequences from the mitochondrial cytochrome c oxidse subunit I gene, as well as multilocus genotype data from nine polymorphic nuclear microsatellite loci. Combined phylogeographic and population genetic analyses clarify the global colonization history of C. maenas, providing evidence of multiple invasions to Atlantic North America and South Africa, secondary invasions to the northeastern Pacific, Tasmania, and Argentina, and a strong likelihood of C. maenas x C. aestuarii hybrids in South Africa and Japan. Successful C. maenas invasions vary broadly in the degree to which they retain genetic diversity, although populations with the least variation typically derive from secondary invasions or from introductions that occurred more than 100 years ago.

JOURNAL Red Shiner Invasion and Hybridization With Blacktail Shiner in the Upper Coosa River, USA 10/23/2008
WALTERS, DAVID M., M. J. BLUM, B. RASHLEIGH, B. J. Freeman, B. A. Porter, AND N. M. Burkhead. Red Shiner Invasion and Hybridization With Blacktail Shiner in the Upper Coosa River, USA. BIOLOGICAL INVASIONS. Springer Science+Business Media, 10(8):1229-1242, (2008).
Abstract: Human disturbance increases the invasibility of lotic ecosystems and the likelihood of hybridization between invasive and native species. We investigated whether disturbance has contributed to the invasion of red shiner (Cyprinella lutrensis) and their hybridization with native blacktail shiner (C. venusta stigmatura) in the upper Coosa River System (UCRS). Historical collection records indicated that red shiners and hybrids have rapidly dispersed in the UCRS via large, mainstem rivers since the mid to late 1990s. We measured the occurrence and abundance of parental species and hybrids near tributary-mainstem confluences and characterized populations at these incipient contact zones by examining variation across morphological traits and molecular markers. Red shiners represented only 1.2% of total catch in tributaries yet introgression was widespread with hybrids accounting for 34% of total catch. Occurrence of red shiners and hybrids was highly correlated with occurrence of blacktail shiners, indicating that streams with native populations are preferentially colonized early in the invasion and that hybridization plays a key role in the establishment and expansion of invasive red shiners and their genome into new habitats. Tributary invasion was driven primarily through advanced generation hybrids exhibiting proportionately greater genomic contributions from blacktail shiner. Occurrence of red shiners and hybrids and the relative abundance of hybrids significantly increased with measures of human disturbance including turbidity, catchment agricultural land use, and low dissolved oxygen concentration. Our findings indicate that red shiners pose a serious threat to Southeast Cyprinella species diversity, given that 41% of these species hybridize with red shiner, that five major southeastern drainages have been invaded, and that these drainages are increasingly disturbed by urbanization.

JOURNAL Physical Indicators of Hydrologic Permanence in Forested Headwater Streams 09/01/2008
FRITZ, K. M., B. R. JOHNSON, AND DAVID M. WALTERS. Physical Indicators of Hydrologic Permanence in Forested Headwater Streams. JOURNAL OF THE NORTH AMERICAN BENTHOLOGICAL SOCIETY. North American Benthological Society, Lawrence, KS, 27(3):690-704, (2008).
Abstract: Recent court cases have brought headwater streams and their hydrologic permanence into the forefront for regulatory agencies, so rapid field-based indicators of hydrologic permanence in streams are critically needed. Our study objectives were to 1) identify environmental characteristics of forested headwater streams that best distinguish perennial, intermittent, and ephemeral reaches, and 2) assess the applicability of existing rapid field-based tools for classifying hydrologic permanence across a wide geographic range. We surveyed reach- and watershed-scale characteristics at 113 sites across 10 study forests in the United States. Four core forests (61 sites) were sampled over two consecutive years and were used in model construction. The other 72 sites (satellite sites) were used to validate the models over a broader geographic range. Hydrologic permanence categories at core sites were significantly different based on discriminant function models. Drainage area, Ohio Environmental Protection Agency's Headwater Habitat Evaluation Index (HHEI), and North Carolina Department of Water Quality's Stream Classificaton Method (NCSC) were strongly correlated with the discriminant function that separated ephemeral from perennial and intermittent sites. Entrenchment ratio was the most consistent variable discriminating intermittent from perennial sites. The models had mixed results on the validation dataset, but did correctly classify most intermittent and ephemeral sites. Classification trees were used to assess broad regional applicability of existing rapid field-based protocols and to identify important metrics. Scores from the Rapid Habitat Assessment (RHA) protocol, HHEI, and NCSC all clearly distinguished ephemeral from intermittent and perennial sites, but no differences were detected between intermittent and perennial sites across all sites. Data from core sites do however indicate that a suite of environmental variables can be used to successfully identify hydrologic permanence at regional scales.

JOURNAL Microsatellite Loci for the Invasive Colonial Hydrozoan Cordylophora Caspia 09/01/2008
Schable, N. A., A. M. Kuenzi, C. A. Drake, N. C. Folino-Rorem, AND J. A. DARLING. Microsatellite Loci for the Invasive Colonial Hydrozoan Cordylophora Caspia. Molecular Ecology Resources. Blackwell Publishing, Malden, MA, 8:968-970, (2008).
Abstract: Cordylophora caspia, a colonial hydrozoan native to the Ponto-Caspian region, has become a common invader of both fresh and brackish water ecosystems of North America and Europe. Here we describe 11 polymorphic microsatellite loci for this species. Preliminary analyses indicate that population sub-structure may contribute to departures from Hardy-Weinberg equilibrium. In addition, the failure of these loci to amplify consistently in Cordylophora samples known to be genetically distant from those utilized in the current study indicates the presence of cryptic diversity within the taxon.

JOURNAL Comparing Trophic Position of Stream Fishes Using Stable Isotope and Gut Contents Analyses 06/01/2008
RYBCZYNSKI, S., DAVID M. WALTERS, K. M. FRITZ, AND B. R. JOHNSON. Comparing Trophic Position of Stream Fishes Using Stable Isotope and Gut Contents Analyses. Ecology of Freshwater Fish. Blackwell Publishing, Malden, MA, 17(2):199-206, (2008).
Abstract: Stable isotope analysis (SIA) and gut content analysis (GCA) are commonly used in food web studies, but few studies analyze these data in concert. We used SIA and GCA to identify diets and trophic position (TP) of six stream fishes and to compare TP estimates between methods. Ordination analysis of gut contents identified two trophic groups, omnivores and predators, with one species intermediate. Predators consumed mostly invertebrates, whereas omnivores consumed detritus, aquatic and terrestrial invertebrates, and plants. Omnivores consumed more terrestrial plants in spring than autumn, but predator diets were seasonally invariant.

JOURNAL Analysis of Ecologically Relevant Pharmaceuticals in Wastewater and Surface Water Using Selective Solid Phase Extraction and Uplc/MS/MS 06/01/2008
BATT, A., M. KOSTICH, AND J. M. LAZORCHAK. Analysis of Ecologically Relevant Pharmaceuticals in Wastewater and Surface Water Using Selective Solid Phase Extraction and Uplc/MS/MS. Analytical Chemistry. American Chemical Society, Washington, DC, 80(13):5021-5030, (2008).
Abstract: A rapid and sensitive method has been developed for the analysis of 48 human prescription active pharmaceutical ingredients (APIs) and 6 metabolites of interest, utilizing selective solid-phase extraction (SPE) and ultra performance liquid chromatography in combination with triple quadrupole mass spectrometry (UPLC/MS/MS). The single-cartridge extraction step was developed using a mixed mode reversed-phase/cation exchange cartridge (Oasis MCX), and validated in both wastewater effluent and surface water. Recoveries for the majority of compounds ranged from 80 to 125%, with relative standard deviations generally below 15%. Analytes were quantified using a multiple injection analysis with four chromatographic runs, with a combined run time of 48 minutes and SPE-LC/MS/MS method detection limits ranging from 1.0 to 51 ng/L. The analysis of seven wastewater effluents and one surface water sample revealed at least one detection for 38 of the 54 compounds, with effluent concentrations ranging from 7 to 2950 ng/L and surface water concentrations ranging from 10 to 140 ng/L. This initial data demonstrates that a significant number of the selected target analytes are present in wastewater treatment plant discharges.

JOURNAL Hybridization Between Invasive Spartina Densiflora (Poaceae) and Native S. Foliosa in San Francisco Bay, California, USA 06/01/2008
AYRES, D. R., E. K. GROTKOPP, K. ZAREMBA, C. M. SLOOP, M. J. BLUM, J. P. BAILEY, C. K. ANTILLA, AND D. R. STRONG. Hybridization Between Invasive Spartina Densiflora (Poaceae) and Native S. Foliosa in San Francisco Bay, California, USA. AMERICAN JOURNAL OF BOTANY. Botanical Society of America Inc., ST. Louis, MO, 95(6):713-719, (2008).
Abstract: Rapid evolution in contemporary time can result when related species, brought together through human-aided introduction, hybridize. The evolutionary consequences of post introduction hybridization range from allopolyploid speciation to extinction of species through genetic amalgamation. Both of these processes are known to occur in the perennial cordgrass genus, Spartina. Here we report the existence of a third Spartina hybridization, discovered in 2002, between introduced S. densiflora and native S. foliosa in San Francisco Bay, California. Coupling classical cytological methods with contemporary methods of flow cytometry, as well as nuclear and chloroplast DNA analysis, we found 32 F1 diploid hybrids and two triploid plants. The presence of diploid and triploid plants is important as it indicates that several avenues exist which may give rise to a new allopolyploid species, offering unique opportunities to observe the inception of a new species as evolution unfolds over decadal timescales.

JOURNAL Polymorphic Microsatellite Loci from Northern and Mexican Corn Rootworms (Insecta: Coleoptera: Chrysomelidae) and Cross-Amplification With Other Diabrotica Spp 06/01/2008
WAITS, E. R. AND U. STOLZ. Polymorphic Microsatellite Loci from Northern and Mexican Corn Rootworms (Insecta: Coleoptera: Chrysomelidae) and Cross-Amplification With Other Diabrotica Spp. MOLECULAR ECOLOGY NOTES. Blackwell Publishing, Malden, MA, 8:707-709, (2008).
Abstract: The northern corn rootworm (Diabrotica barberi) and Mexican corn rootworm (Diabrotica virgifera zeae) are significant agricultural pests. For the northern corn rootworm, and to a lesser extent, the Mexican corn rootworm, high resolution molecular markers are needed. Here we present fourteen polymorphic microsatellite loci isolated from libraries constructed using pooled northern and Mexican corn rootworm genomic DNA. Polymorphism in other Diabrotica, including the banded cucumber beetle, southern corn rootworm and western corn rootworm, is described.

JOURNAL A Core Set of Microsatellite Markers for Western Corn Rootworm (Coleoptera: Chrysomelidae) Population Genetics Studies 04/01/2008
Kim, K., U. STOLZ, N. J. Miller, E. R. WAITS, T. Guillemaud, D. V. Sumerford, AND T. W. Sappington. A Core Set of Microsatellite Markers for Western Corn Rootworm (Coleoptera: Chrysomelidae) Population Genetics Studies. ENVIRONMENTAL ENTOMOLOGY. Entomological Society of America, Lantham, MD, 37(2):293-300, (2008).
Abstract: Interest in the ecological and population genetics of the western corn rootworm, Diabrotica virgifera virgifera LeConte, has grown rapidly in the last few years in North America and Europe. This interest is a result of a number of converging issues related to increasing difficulty in managing this pest, and the need to characterize and understand gene flow in the context of insect resistance management. One of the key components needed for successful population genetics studies is the availability of suitable molecular markers. Using a standard group of microsatellite markers enables researchers from different laboratories to directly compare and share their data, reducing duplication of effort and facilitating collaborative work among laboratories. We screened 22 candidate microsatellite loci against six criteria to create a core set of microsatellite markers for D. v. virgifera population genetics studies. The criteria for inclusion were moderate to high polymorphism, readability and repeatability, no evidence of null alleles, selective neutrality, no linkage between loci, and cross-taxa amplification ability. Based on the results, we recommend a core set of six microsatellite markers to be used in futgure population genetics studies of D. v. virgifera. As more microsatellites are developed, those meeting the criteria can be added to the core set. We encourage other groups of researchers with common interests in a particular insect species to develop core set of markers for population genetics applications.

JOURNAL Field and Laboratory Performance Characteristics of a New Sampling Protocol for Riverine Macroinvertebrate Assemblages 04/01/2008
BLOCKSOM, K. A. AND J. E. FLOTEMERSCH. Field and Laboratory Performance Characteristics of a New Sampling Protocol for Riverine Macroinvertebrate Assemblages. River Research and Applications. John Wiley & Sons Incorporated, New York, NY, 24(4):373-387, (2008).
Abstract: Measurement and estimation of performance characteristics (i.e., precision, bias, performance range, interferences and sensitivity) are often neglected in the development and use of new biological sampling methods. However, knowledge of this information is critical in enabling potential users to assess data quality and make comparisons among different sampling methods. In this study, the performance characteristics were evaluated for both the field and laboratory components of a new macroivnertebrate sampling protocol (mLR-BP) for nonwadeable streams (Flotemersch et al. 2004). We sampled 19 sites across two depth classes, collecting three replicate samples at each site and sorting three 300-organism subsamples from each sample. The replicate samples provided data for estimates of precision in the laboratory and the field, and water chemistry and habitat variables allowed for measurements of overall sensitivity. Precision, sensitivity and performance range all differed between shallow and deep sites, particularly for the field component. The precision was improved and performance range was larger for shallow sites, but differences in sensitivity indicated that the two depth classes may require different sets of metrics as indicators. As compared with precision measured in other studies of bioassessment methods, the field component of the mLR-BP performed similarly, particularly in shallow sites. If used for bioassessment in similar types of rivers, this protocol should be able to detect differences of approximately 10-20% in the metrics evaluated in this study. The sampling protocol shows great utility for bioassessment and monitoring of nonwadeable rivers, as well as for measuring the success of restoration efforts. In addition, the design of this study provides a template for estimating performance characteristics in other nonwadeable systems.

JOURNAL The Quagga Mussel Invades the Lake Superior Basin Journal Article 04/01/2008
Grigorovich, I. A., J. R. KELLY, J. DARLING, AND C. W. WEST. The Quagga Mussel Invades the Lake Superior Basin Journal Article. JOURNAL OF GREAT LAKES RESEARCH. International Association for Great Lakes Research, Ann Arbor, MI, 34(2):342-350, (2008).
Abstract: Prior studies recognized the presence of a single dreissenid species in Lake Superior--the zebra mussel Dreissena polymorpha. However, taxonomic keys based on traditional shell morphology are not always able to differentiate dreissenid species with confidence. We thus employed genetic and morphological analyses to identify dreissenids in a major river-embayment of Lake Superior--the lower St. Louis River/Duluth-Superior Harbor--during 2005 - 2006. Our results revealed the presence of a second dreissenid species--the quagga mussel D. bugensis (alternatively known as D. rostriformis bugensis). Both species occurred in mixed clusters, in which zebra mussels outnumbered quagga mussels. The largest quagga mussel collected in 2005 was 26.5 mm long and estimated to be two years old, suggesting that the initial introduction occurred no lather than 2003. Further monitoring is necessary to determine whether the quagga ussel will colonize Lake Superior. Our results indicate that the coupling of conventional morphological approaches is essential for monitoring dreissenid species.

JOURNAL Primary Producers and Nutrient Loading in Silver Springs, Fl, USA 04/01/2008
QUINLAN, E. L., E. J. Phlips, K. A. Donnelly, C. H. Jett, P. Sleszynski, AND S. Keller. Primary Producers and Nutrient Loading in Silver Springs, Fl, USA. AQUATIC BOTANY. Elsevier Science Ltd, New York, NY, 88(3):247-255, (2008).
Abstract: The characteristics and dynamics of primary producer communities of Silver Springs was examined to compare with that observed by Odum as a means of evaulating the impacts of changes that have occurred over time. The Silver Springs ecosystem is considered an ecosystem at risk, where nitrate levels have more than doubled over the past 50 years. The spatial and temporal abundance and distribution of above-sediment primary producers in Silver Springs, FL, USA was estimated on a system-wide basis using a GIS platform. The results of study suggest that while the Sagittaria component of Silver Springs has remained relatively stable, epiphyte and benthic algal mat community biomass has expanded, particularly enthic forms, like Lyngbya. However, we argue for caution in weighing the significance of long-term comparisons of system-wide biomass in light of considerable spatial heterogeneity in aquatic primary producer communities.

JOURNAL Risks to Aquatic Organisms Posed By Human Pharmaceutical Use 01/25/2008
KOSTICH, M. S. AND J. M. LAZORCHAK. Risks to Aquatic Organisms Posed By Human Pharmaceutical Use. SCIENCE OF THE TOTAL ENVIRONMENT. Elsevier Science Ltd, New York, NY, 389(2-3):329-339, (2008).
Abstract: In order to help prioritize future research efforts within the US, risks associated with exposure to human prescription pharmaceutical residues in wastewater were estimated from marketing and pharmacological data. Masses of 371 active pharmaceutical ingredients (APIs) dispensed in the US in 2004 were estimated from marketing data, and then divided by therapetuic dose rate to normalize for potency. Metabolic inactivation of the 50 most dispensed APIs was estimated from published data, and active metabolites were tabulated. Comparing maximum likely average wastewater concentrations of API-associated activity to exposure rates that produce therapetuic effects in humans suggests that the threat to healthy human adults from aquatic exposure is low, even when likely mixture effects are considered. Comparing predicted wastewater concentrations to human therapetuic plasma concentrations suggests that some APIs may be present at sufficient concentrations to affect organisms which eliminate them inefficiently. Comparing predicted antimicrobial concentrations to published minimum inhibitory concentrations suggests that antibacterial APIs in wastewater, but probably not antifungal APIs, may select for low-level antimicrobial resistance. The taxonomic distribution of molecular targets of the 50 most dispensed APIs suggests that potential effects of some APIs are likely restricted to vertebrates, while other APIs can probably affect many eukaryotic and prokaryotic clades.

NEWSLETTER ARTICLE Selecting for Resistance to the Cry3bb1 Protein in a Genetically Diverse Population of Non-Diapausing Western Corn Rootworm 04/01/2008
French, B., M. BAGLEY, C. Nielson, AND U. STOLZ. Selecting for Resistance to the Cry3bb1 Protein in a Genetically Diverse Population of Non-Diapausing Western Corn Rootworm. In: Resistant Pest Management Newsletter, Michigan State University, East Lansing, MI, 14(2):54, (2008).
Abstract: Abstract published in Resistant Pest Management Newsletter, a biannual newsletter of the Center for Integrated Plant Systems (CIPS) in cooperation with the Insecticide Resistance Action Committee (IRAC) and the Western Regional Coordinating Committee (WRCC-60).

PRESENTATION Development of Rapid Methods for Measuring Stream Ecosystem Functions in the Appalachian Coal Mining Region: Preliminary Results 12/11/2008
JOHNSON, B. R., K. M. FRITZ, AND R. Price. Development of Rapid Methods for Measuring Stream Ecosystem Functions in the Appalachian Coal Mining Region: Preliminary Results. Presented at West Virginia Coal Association, Charleston, WV, December 11, 2008.
Abstract: Headwater streams represent the majority of U.S. stream miles. As a consequence of being abundant and widespread, the alteration and loss of headwater streams may have impacts on downstream waterbodies. These streams are frequently the subject of proposed dredge and fill projects (e.g., road building, valley-fills). Under Section 404 of the Clean Water Act, the Army Corps of Engineers (COE) and the USEPA must fairly identify potential impacts to stream functions and values associated with proposed activities for mitigation purposes. However, the traditional approach to stream assessment has been to use structural measures as indicators of condition rather than directly assess the functional properties of water bodies. Structural measures identify the organization and composition of the physical, chemical and biological components in a system (e.g., diversity, abundance), whereas function measures are the dynamic properties of systems such as processes and rates (e.g., decomposition, metabolism). Functional measures may be preferred over structural measures because they can be more readily linked to economic and ecological value, particularly for headwater streams which are frequently not direct resources for municipal and recreational uses. This study will provide rapid techniques to measure functional properties that can be used by the regulating community, but also justify the use of some structural properties as indirect measures for the function of running waters.

PRESENTATION Overview of Approaches Currently Being Used By USEPA to Assess Source, Exposure and Fate of Contaminants of Emerging Concern in the Environment 11/17/2008
LAZORCHAK, J. M., D. L. LATTIER, D. C. BENCIC, A. D. BIALES, M. KOSTICH, A. BATT, E. L. QUINLAN, AND H. Poynton. Overview of Approaches Currently Being Used By USEPA to Assess Source, Exposure and Fate of Contaminants of Emerging Concern in the Environment. Presented at SETAC, Tampa, FL, November 16 - 20, 2008.
Abstract: Contaminants of emerging concern are physical, chemical or biological pollutants for which previous exposures to aquatic life were not widely documented, for which the effects of exposures were not completely recognized, that are new materials whose environmental behavior and toxicity are not fully understood or are currently not included in routine monitoring programs and which may be candidates for future regulation, depending on research on their (eco)toxicity, potential health effects, public perception, and on monitoring data regarding their occurrence in the various environmental compartments.

PRESENTATION What's Good for the Fish Is Good for the People! Aquatic Sentinels Forecasting Human Exposure to Emerging Contaminants 11/17/2008
LAZORCHAK, J. M., D. L. LATTIER, M. KOSTICH, AND JOEL J. ALLEN. What's Good for the Fish Is Good for the People! Aquatic Sentinels Forecasting Human Exposure to Emerging Contaminants. Presented at SETAC, Tampa, FL, November 16 - 20, 2008.
Abstract: The term "contaminant of emerging concern" is being used within the Office of Water to replace "emerging contaminant", a term that has been used loosely since the mid-1990s by EPA and others to identify chemicals and other substances that have no regulatory standard, have been recently discovered in natural streams (often because of improved analytical chemistry detection levels), and potentially cause deleterious effects in aquatic life at environmentally relevant concentrations. They are pollutants not currently included in routine monitoring programs and may be candidates for future regulation depending on their (eco)toxicity, potential health effects, public perception, and frequency of occurrence in environmental media. CECs are not necessarily new chemicals. They include pollutants that have often been present in the environment, but whose presence and significance are only now being evaluated.

PRESENTATION Consequences of Tetracycline Exposure to Stream Periphyton in An Experimental Mesocosm Study 11/17/2008
QUINLAN, E. L., C. T. NIETCH, J. M. LAZORCHAK, AND R. A. GRIFFITHS. Consequences of Tetracycline Exposure to Stream Periphyton in An Experimental Mesocosm Study. Presented at SETAC, Tampa, FL, November 16 - 20, 2008.
Abstract: A significant amount of ingested, injected, and applied antibiotics are not metabolized but are excreted; entering the environment via point and non-point sources. Tetracycline and its derivatives are among the most extensively used human and animal antibiotics. We examined the consequences of tetracycline exposure within a stream periphyton community across a logarithmically dosed-series of experimental mesocosms receiving water from the East Fork of the Little Miami River in Milford, OH. Target in-stream tetracycline exposures were based upon previously reported concentrations in streams and rivers throughout the United States (<1 – 100 µg L-1), and included a control. Our results indicated significant changes in the periphyton community with in-stream tetracycline concentration as low as 0.5 µg L-1, and effects magnified in proportion with increased dosing rate, including decreases in abundance of bacteria and algae, decreased bacteria productivity, and compositional shifts in the algal community. An increase in bacteria resistance to tetracycline was also observed at all doses. Recovery of the periphyton community ranged from days to several weeks depending on the organism and dosing concentration.

PRESENTATION Integration of Genomic Endpoints Into Toxicity Identification Evaluations 11/17/2008
BIALES, A. D., K. T. HO, R. M. BURGESS, M. M. Perron, M. KOSTICH, AND M. REISS. Integration of Genomic Endpoints Into Toxicity Identification Evaluations. Presented at SETAC, Tampa, FL, November 16 - 20, 2008.
Abstract: Toxicity identification and evaluations (TIEs) use physical/chemical manipulation of a sample to isolate or change the potency of different groups of toxicants potentially present in a sample. Organisms are then exposed to these fractions to determine if their toxicity has changed. TIEs focus on mortality to detect toxicity; however, this endpoint gives no information as to the identity of the active toxicant(s). It has been suggested that gene expression profiles may be useful in identifying toxic substances fromunknown samples. This is accomplished through the development of expressionn profiles, consisting of a number of genes, which respond in a specific manner to a given contaminant. Transcriptional profiling of toxicants is usually accomplished using microarrays; however, this technological platform does not currently exist for a common model organism used in TIEs, the amphipod, Ampelisca abdita. Therefore, normalized libraries for A. abdita were constructed. Organisms used in library construction were selected to be diverse as possible to increase the number of transcripts included in the library and included multiple age groups, populations from different geographic areas and organisms that were subjected to chemical exposures. Over 6000 clones were sequenced in both directions and will be spotted in duplicate on microarrays. For transcriptional profiling, A. abdita were exposed in sediments to 7 chemicals, a binary mixture and a grand mixture of all test chemicals at a dilution corresponding to 10% of the LC50 value for each chemical. Each exposure consisted of 6 independent replicates. Each replicate consisted of a pool of 10 individuals. Transcriptional fingerprints will be established for each chemical and the stability of these profiels will be evaluated in the mixtures. Following establishment of chemical specific transcriptional profiels, A. abdita will be exposed to an environmentally contaminated sediment sample, on which a TIE will be performed. Exposed individuals will be usbject to microarray screening to determine if active toxic substances can be identified. These results will subsequently be compared to the TIE outcome. This will be among the first projects to integrate genomic technology into existing toxicity assessment experimental platforms.

PRESENTATION Effects of Hypoxia on the Response of Fish to Estrogen Exposure 11/17/2008
FLICK, R. W., J. M. LAZORCHAK, AND J. Oris. Effects of Hypoxia on the Response of Fish to Estrogen Exposure. Presented at SETAC, Tampa, FL, November 16 - 20, 2008.
Abstract: Natural and synthetic estrogens are common contaminants in surface waters and have the potential to affect reproduction in fish. Estrogens are likely to co-occur with low dissolved oxygen (DO) levels, which result from inputs of organic material in wastewater effluents or from animal production facilities. Low DO, or hypoxia, is a significant cause of impairment in streams and rivers. Their co-occurrence is particularly significant because the transcriptional responses to hypoxia and estrogen share a common element in their pathways. Therefore, the production of vitellogenin, which is often used as a biomarker of exposure to estrogens, may be affected by exposure to hypoxia. In order to determine if exposure to hypoxia altered the response of fish to estrogens, we performed laboratory exposures of fish to both hypoxia and 17a-ethynylestradiol (EE2) and used real-time PCR to analyze vitellogenin expression in liver tissue. In initial experiments fathead minnows were exposed to DO levels of approximately 2.5 mg/L for up to six hours; EE2 was then added to achieve a final concentration of 10 ng/L EE2, and exposure continued for 16 to 24 hours. Results from these experiments suggest that hypoxia does not substantially alter vitellogenin expression in short-term exposures to EE2 in fathead minnows compared to EE2-only exposed controls; however, larger sample sizes are necessary to verify these results. We will also investigate whether the transcriptional response is dependent upon duration of exposure and whether the expression of other genes, such as HIF-1a, is affected. In the future we hope to determine whether these responses are species-specific. Understanding the influence of non-chemical stressors on estrogenic responses in aquatic organisms is essential for accurate ecological assessment. If vitellogenin expression were found to be significantly altered by exposure to hypoxia, then its use as a biomarker to diagnose exposure to estrogens would require data on DO levels in order to accurately assess the level of exposure to estrogenic compounds.

PRESENTATION Methods to Measure Indicators of Exposure in Real-World Aquatic Environments 11/16/2008
LAZORCHAK, J. M., R. W. FLICK, A. D. BIALES, D. A. GORDON, D. C. BENCIC, G. T. ANKLEY, D. H. MILLER, A. Awan, AND L. ZINTEK. Methods to Measure Indicators of Exposure in Real-World Aquatic Environments. Presented at SETAC, Tampa, FL, November 16 - 20, 2008.
Abstract: Most of what is known about the implications of endocrine disrupting chemicals in the environment is somewhat anecdotal. There are numerous reports of gonadal histological abnormalities (Potomac, United Kingdom Rivers), alterations in sex ratios (Boulder Creek, Colorado) and high vitellogenin protein levels in fish below wastewater treatment plants. There has been some linear regression modeling describing the relationship between estrogens and relative fecundity linked to population models to predict trajectories of decreases in population size. However, there remains no clear and direct field-measured linkage between observed abnormalities and population level effects. In the case of the Potomac, community level measures such as indices of biotic integrity showed no relationships to ova-testis in smallmouth bass. One recent study in 2007 did show a collapse of fathead minnows, pearl dace and lake trout populations over a 5 year study in which a whole lake was dosed for 3 years with ethynylestradiol. Indicators were measured in this study from the molecular level to the whole animal level in order to link such measures to population effects. Only weight of evidence relationships could be drawn from this study, however, some of the molecular level indicators did show indication of estrogen exposure before the Catch Per Unit Effort (CPUE) fish collections showed significant reductions in population size. Understanding when and how exposures occur are critical factors that impact the ability to understand the potential impacts of EDCs.

PRESENTATION Pharmaceuticals in the Environment - Exposure, Effects and Risks to Humans and Ecosystems: What We Think We Know, and What We Need to Know 11/10/2008
LAZORCHAK, J. M., M. KOSTICH, AND S. GLASSMEYER. Pharmaceuticals in the Environment - Exposure, Effects and Risks to Humans and Ecosystems: What We Think We Know, and What We Need to Know. Presented at Environmental Health Summitt, Research Triangle Park, NC, November 10 - 11, 2008.
Abstract: U.S., European and Korean environmental monitoring and research programs have confirmed the occurrence of low levels of pharmaceuticals in stream waters, in soils and streambed sediments, in ground water, in estuaries, and in drinking water.

PRESENTATION In-Situ Exposure of Fish for Biomarker Experimentation at Department of Water Resources (Dwr) Real-Time Monitoring Sites 10/23/2008
Riordan, D. AND A. D. BIALES. In-Situ Exposure of Fish for Biomarker Experimentation at Department of Water Resources (Dwr) Real-Time Monitoring Sites. Presented at 5th Biennial CALFED Science Conference 2008, Sacramento, CA, October 22 - 24, 2008.
Abstract: For decades, the field of aquatic toxicology has assessed the health of water bodies using, primarily, laboratory based static-renewal toxicity tests. In recent years, there has been a push to supplement traditinal toxicity tests with experiments using molecular biomarkers to determine the physiological and biochemical responses of an organism to specific stressors. Molecular changes often result from the direct binding of a toxicant to its cognate receptor and thus are toxicant specific. Because they occur proximal to exposure, these changtes are often tied directly to the toxicity and can potentially inform the mechanisms of action. One of the most well characterized molecular biomarkers is vitellogenin (Vtg) gene expression. Vtg is usually quiescent in males, but can be induced upon exposure toe strogenic compounds, which have been shown to negatively affect the reproductive capacity of aquatic vertebrates. We have desinged a system that screens for estrogen mimicking compounds while exposing male fish in-situ. During two successive years, adult male fathead minnows were exposed to ambient water in flow through systems at two DWR field sites, the Sacramento River at Hood, and the San Joaquin River at Vernalis, for seven days for four successive weeks in both low and high flow periods. The second year had an additional 28-day exposure concurrent witht he four single week exposures. Upon test termination, the brain, liver and gonads of each individual were removed and flash-frozen. Liver samples were analyzed for Vtg expression using Real-Time quantitative Polymerase Chain Reaction analysis and all samples were analyzed for histological anomalies. For year one, Vtg gene expression was elevated for several weeks at the Hood field station. Year two QPCR and histological results are pending. These data indicate the presence of estrogenically active substances in the Sacramento River, which coincides with periods of high flow.

PRESENTATION Removing Mountains & Filling Valleys: Appalachian Coal Mining & Headwater Streams 10/22/2008
FRITZ, K. M. Removing Mountains & Filling Valleys: Appalachian Coal Mining & Headwater Streams. Presented at Appalachian State University Department of Biology Seminar, Boone, NC, October 22, 2008.
Abstract: Oral presentation (invited speaker) at Appalachian State University, Department of Biology Seminar.

PRESENTATION Managing Saginaw Bay Nutrient Loading By Surrounding Watersheds Through Near Real Time Hydrologic Resource Sheds 10/14/2008
Croley, T. E., C. He, C. DeMarchi, AND D. RAIKOW. Managing Saginaw Bay Nutrient Loading By Surrounding Watersheds Through Near Real Time Hydrologic Resource Sheds. Presented at IHP 2008: The Role of Hydrology in Water Resources Management, Capri, ITALY, October 13 - 16, 2008.
Abstract: We can quantify source areas contributing material to a location during various time periods as resource sheds. Various kinds of resource sheds and their source material distributions are defined. For watershed hydrology, we compute resource sheds and their source material distributions with a spatially distributed hydrology model by tracing material departing from a cell over one time interval and arriving at the watershed mouth in another time interval. This requires modeling all cells, but only tracing contributions from one at a time. By then combining these simulations for all cell loadings, we construct a map of the contributions over the entire watershed for specific departure and arrival time intervals. We then combine results of several sets of simulations to determine the source distribution for any time period and infer resource sheds from these mappings. We present Saginaw Bay watershed examples, discuss methods of computation reduction, and suggest areas of extension. To estimate nutrient delivery to Saginaw Bay under alternate scenarios, we expanded our spatially distributed hydrology models to include sediment and nutrient transport, assembled in-stream quality data relevant to nutrient watershed loading surveys, calibrated transport models by using both historical and new databases, estimated climate and land use changes impacts on nutrient inputs to Saginaw Bay, and enabled resource shed mappings of both water and water quality parameters. We compute resource shed maps in near real time for the four Saginaw Bay watersheds for water flows as well as for sediment, phosphorus and nitrates. This allows watershed planners and managers to track events in the bay back into watershed source areas.

PRESENTATION Regional Methods Program: Development of Rapid Measures of Stream Ecosystem Functions in the Appalachian Mining Region 10/10/2008
JOHNSON, B. R., K. M. FRITZ, AND R. Price. Regional Methods Program: Development of Rapid Measures of Stream Ecosystem Functions in the Appalachian Mining Region. Presented at Biological Advisory Committee Annual Meeting, Fort Meade, MD, October 09 - 11, 2008.
Abstract: Oral presentationat the Biological Advisory committee annual meeting.

PRESENTATION Identification of Biomarkers of Exposure to Metal-Based Nanoparticles Through Gene Expression Profiling Using Daphnia Magna Micro-Arrays 10/08/2008
LAZORCHAK, J. M., H. Poynton, CHRISTOPHER IMPELLITTERI, JOEL J. ALLEN, MARK E. SMITH, K. Hammer, K. R. ROGERS, AND M. Patra. Identification of Biomarkers of Exposure to Metal-Based Nanoparticles Through Gene Expression Profiling Using Daphnia Magna Micro-Arrays. Presented at International Environmental Nanotechnology Conference: Applications and Implications, Chicago, IL, October 07 - 09, 2008.
Abstract: Oral presentation at the International Environmental Nanotechnology Conference, Chicago IL, October 7-9, 2008.

PRESENTATION Estimating Aquatic Hazards Posed By Prescription Pharmaceutical Residues from Municipal Wastewater 10/03/2008
KOSTICH, M. AND J. M. LAZORCHAK. Estimating Aquatic Hazards Posed By Prescription Pharmaceutical Residues from Municipal Wastewater. Presented at SETAC 2008 Ohio Valley Chapter, Bloomington, IN, October 03, 2008.
Abstract: Risks posed by pharmaceuticals in the environment are hard to estimate due to limited monitoring capacity and difficulty interpreting monitoring results. In order to partially address these issues, we suggest a method for prioritizing pharmaceuticals for monitoring, and a framework for converting concentration measurements into hazard estimates. We used publicly available marketing and wastewater statistics to estimate national annual consumption of about 400 prescription active pharmaceutical ingredients (APIs), and resulting maximum average concentrations of APIs in raw wastewater. For each API, we used known pharmacological parameters as LOECs for calculating hazard ratios for humans, microbes and other organisms. Similar hazard ratios were calculated for mixtures of pharmaceuticals sharing modes of action. In order to estimate potential local variability of these hazards, our analyses was extended to the state and three-digit zip code levels for a subset of pharmaceuticals for which local distribution data is available. This approach has allowed us to prioritize analytes for monitoring based on potential hazard, estimate maximum likely aquatic hazards posed by APIs that have never been monitored, and provide a reasonable framework for interpreting monitoring results in the absence of extensive ecotoxicological data.

PRESENTATION Tracking Contaminant Flux from Aquatic to Terrestrial Food Webs 08/26/2008
WALTERS, DAVID M., K. M. FRITZ, D. RAIKOW, M. MILLS, AND R. R. Otter. Tracking Contaminant Flux from Aquatic to Terrestrial Food Webs. Presented at 6th International Conference on Applications of Stable Isotope Techniques to Ecological Studies, Honolulu, HI, August 25 - 29, 2008.
Abstract: Aquatic insects provide a critical energy subsidy to riparian food webs, yet their role as vectors of contaminants to terrestrial ecosystems is poorly understood. We investigated aquatic resource utilization and contaminant exposure among riparian invertivores (spiders and herptiles) along a stream and reservoir contaminated with polychlorinated biphenyls (PCBs). Aquatic insect utilization varied among stream riparian predators, as predators shifted from aquatic to terrestrial prey. We sampled spiders and insects at various distances (0-30 m) from the reservoir shore to quantify the lateral extent of contaminant flux. Aquatic insect flux was limited to the first 5 m of the shore. Riparian spiders preyed heavily on aquatic insects along the shore, but switched to terrestrial prey beyond 5-10 m of the shore. PCB concentrations tracked these patterns in aquatic insect utilization and declined rapidly beyond 5 m from the shore. Persistent contaminants (e.g., PCBs) are underutilized for addressing landscape-level questions in subsidy research, but our results demonstrate that they are an ideal in situ tracer of aquatic-derived energy because they label aquatic insects over large distances. Likewise, riparian predators such as spiders have great potential as biological monitors of ecosystem condition and as assessment tools for risk management of contaminated aquatic sediments.

PRESENTATION Ecotoxicogenomics Short Course Proteomics 08/05/2008
BENCIC, D. C., A. D. BIALES, AND J. M. LAZORCHAK. Ecotoxicogenomics Short Course Proteomics. Presented at 5th SETAC World Congress, Sydney, AUSTRALIA, August 03 - 07, 2008.
Abstract: Presentation at the 5th SETAC World Congress, Sydney, Australia, August 3-7, 2008.

PRESENTATION Spatial and Functional Characterization, Identification and Assessment of Isolated Wetlands in Alachua County, Florida, USA GIS and Remote Sensing Techniques 08/05/2008
Reif, M., R. C. Frohn, C. R. LANE, B. C. AUTREY, AND E. D'Amico. Spatial and Functional Characterization, Identification and Assessment of Isolated Wetlands in Alachua County, Florida, USA GIS and Remote Sensing Techniques. Presented at ESRI Conference, San Diego, CA, August 04 - 08, 2008.
Abstract: In this study, Geographic Information Systems (GIS) and remote sensing mapping techniques were developed to identify the locations of isolated wetlands in Alachua County, FL, a 2510 sq km area in north-central Florida with diverse geology and numerous isolated wetlands. The results of the stand-alone and combined GIS and remote sensing analyses were assessed by comparing the mapped isolated wetlands to an accuracy dataset, using an "intersection" approach. The combined GIS and remote sensing method performed the best of all methods developed, with producer accuracies ranging from 93-100% and user accuracies ranging from 86-95%, depending on wetland size. In addition, both the stand-alone remote sensing method and the combined GIS/remote sensing method were especially successful at identifying smaller isolated wetlands, down to 0.5 acre in size, which can be difficult and time consuming to map using aerial photointerpretation. Using Light Detection and Ranging (LIDAR) imagery, wetland bathymetry and volume studies are currently being conducted o the identified isolated wetlands to determine relationships between wetland type, area, and water storage capacity. This hydrological modeling will be used to identify isolated wetland contribution to hydrologic dynamics and downstream condition and conduct landscape-level analyses of the ecosystem services provided by these aquatic systems.

PRESENTATION Molecular Techniques from a Regulatory Perspective 08/05/2008
LAZORCHAK, J. M., D. C. BENCIC, AND A. D. BIALES. Molecular Techniques from a Regulatory Perspective. Presented at 5th SETAC World Congress, Sydney, AUSTRALIA, August 03 - 07, 2008.
Abstract: Presentation at the 5th SETAC World Congress, Sydney, Australia, August 3-7, 2008

PRESENTATION Gene Expression, Proteomics and Microarrays and Their Respective Informatic Approaches to Address Ecotoxicological Issues (Gene Expression, Proteomics and Microarrays) 08/05/2008
BIALES, A. D., D. C. BENCIC, AND J. M. LAZORCHAK. Gene Expression, Proteomics and Microarrays and Their Respective Informatic Approaches to Address Ecotoxicological Issues (Gene Expression, Proteomics and Microarrays). Presented at 5th SETAC World Congress, Sydney, AUSTRALIA, August 03 - 07, 2008.
Abstract: Presentation at the 5th SETAC World Congress, Sydney, Australia, August 3-7, 2008

PRESENTATION EPA's Future Midwestern Landscapes Study 07/29/2008
BRUINS, R. J. EPA's Future Midwestern Landscapes Study. Presented at Soil Water Conservation Society Annual Meeting, Tucson, AZ, July 26 - 30, 2008.
Abstract: Overview of the future midwestern landscapes study at the annual meeting of the Soil Water Conservation Society, Tucson, Arizona, July 26-30, 2008.

PRESENTATION EPA's Future Midwestern Landscapes (Fml) Study 07/26/2008
BRUINS, R. J. EPA's Future Midwestern Landscapes (Fml) Study. Presented at Soil and Water Conservation Society Annual Meeting, Tucson, AR, July 25 - 30, 2008.
Abstract: EPA's ecological research program is initiating research to characterize ecosystem services and enable their routine consideration in environmental management and policy. The "Future Midwestern Landscapes (FML) Study" is one of four place-based studies being planned. Over a 13-state area of the Midwest, for a baseline year and at least two alternative future scenarios, FML will construct detailed land use/land cover maps and characterize a variety of services.

PRESENTATION Mappping Isolated Wetlands With GIS and Remote Sensing in North Central Florida USA 06/29/2008
LANE, C. R., M. Reif, R. C. Frohn, AND B. C. Autrey. Mappping Isolated Wetlands With GIS and Remote Sensing in North Central Florida USA. Presented at ENVIROMIS - 2008, Tomsk, RUSSIA, June 28 - July 06, 2008.
Abstract: Presentation at the ENVIROMIS 2008 international conference on environmental observations, modeling and information systems, Tomsk, Russia, June 28 - July 6, 2008.

PRESENTATION Genetic Analysis Reveals Multiple Cryptic Invasive Species of the Hydrozoan Genus Cordylophora 06/21/2008
DARLING, J. AND N. C. Folino-Rorem. Genetic Analysis Reveals Multiple Cryptic Invasive Species of the Hydrozoan Genus Cordylophora. Presented at Evolution 2008, Minneapolis, MN, June 20 - 24, 2008.
Abstract: Oral presentation at Evolution 2008, Minneapolis, MN, June 20-24, 2008.

PRESENTATION Benthic Diatom Composition in Wet and Dry Isolated Forested Wetlands: Implications for Monitoring and Assessment (Presentation) 05/27/2008
LANE, C. R., K. Reiss, SUSANNA J. DECELLES, AND M. T. Brown. Benthic Diatom Composition in Wet and Dry Isolated Forested Wetlands: Implications for Monitoring and Assessment (Presentation). Presented at Society of Wetland Scientists Annual Meeting, Washington, DC, May 26 - June 03, 2008.
Abstract: Oral presentation - no abstract

PRESENTATION A Predictive Model for Anti-Degradation Monitoring of the Delaware River Mainstem 05/26/2008
BLOCKSOM, K. A., J. E. FLOTEMERSCH, R. L. Limbeck, AND E. Silldorff. A Predictive Model for Anti-Degradation Monitoring of the Delaware River Mainstem. Presented at North American Benthological Society, Salt Lake City, UT, May 25 - 30, 2008.
Abstract: The non-tidal portion of the Delaware River can be considered to be in minimally disturbed condition, but there is increasing pressure on the watershed. Thus, the primary goal of this research was to develop a monitoring tool that can be used by the Delaware River Basin Commission (DRBC) to monitor for changes in the macroinvertebrate assemblage that may be a result of human disturbance in the basin. To this end, we developed a RIVPACS-type predictive model for the river using the conditions in 2006 as a baseline. We first verified the sections of river that are considered representative of minimal disturbance by the DRBC and National Park Service personnel. We identified 5 groups of sites using flexible beta clustering based on benthic macroinvertebrate data from riffles, glide/runs, and pools. We then developed a discriminant model based on maximum velocity, mean water depth, latitude, and a regional indicator variable. The final predictive model and this approach in general, provide DRBC and the National Park Service with an approach for early detection of changes to the river.

PRESENTATION Are Bryophytes Useful Indicators of Hydrologic Permanence in Forested Headwater Streams? 05/26/2008
FRITZ, K. M. Are Bryophytes Useful Indicators of Hydrologic Permanence in Forested Headwater Streams? Presented at North American Benthological Society, Salt Lake City, UT, May 25 - 30, 2008.
Abstract: Court cases have recently questioned whether all headwater streams, particularly non-perennial streams, should be protected in the U.S. under the Clean Water Act. Rapid field-based indicators of hydrologic permanence are needed for jurisdictional determinations. The study objective was to determine whether bryophytes in forested headwater streams are useful indicators of hydrologic permanence. Bryophytes were sampled from the channel thalweg at 113 sites which varied in hydrologic permanence. Species compositon differed between ephemeral and perennial stream reaches; however, the species composition of intermittent streams overlapped with ephemeral and perennial streams. Three species and six families were identified as indicators of specific permancnce classes. Liverworts occurred more frequently at perennial than at intermittent or ephemeral sites. Bryophytes with cushion and turf growth forms were common at ephemeral sites, whereas mat and weft forms were more common at perennial sites. Species richness was significantly higher at ephemeral than at perennial sites, but neither was significantly different from intermittent sites. Bryophytes should be included among the tools for jurisdictional determinations, much like vascular plants are useful for delineatring wetlands.

PRESENTATION Ecological Consequences of Antibiotic Exposure to Periphyton in Naturally Colonizing Stream Mesocosms 05/26/2008
QUINLAN, E. L., C. T. NIETCH, AND J. M. LAZORCHAK. Ecological Consequences of Antibiotic Exposure to Periphyton in Naturally Colonizing Stream Mesocosms. Presented at North American Benthological Society, Salt Lake City, UT, May 25 - 30, 2008.
Abstract: Tetracycline and its derivatives are extensively used human and animal antibiotics, and enter stream ecosystems via point and non-point sources. Laboratory studies indicate that microbial organisms are more sensitive to antibiotics than invertebrates or fish, and may indicate the presence of antibiotics in aquatic ecosystems. We examined the consequences of tetracycline exposure to a periphyton community across a logarithmically dosed-series of experimental mesocosms receiving water from the East Fork of the Little Miami River in Milford, OH. Mesocosms were colonized naturally, dosed, and then allowed to recover, each period lasting 30 days. Target in-stream tetracycline exposures were based upon previously reported concentrations in streams and rivers throughout the United States (<1 – 100 µg L-1), and included a control. Our results indicated significant changes in the periphyton community with in-stream tetracycline concentrations as low as 0.5 µg L-1, and effects magnified in proportion with increased dosing rate, including decreases in abundance of bacteria and algae, decreased bacteria productivity, and algal compositional shifts. Recovery of the periphyton community ranged from days to several weeks depending on the organism and dosing concentration. These results suggest the potential for shifts in the trophic structure of streams after sustained (days) exposure to antibiotics.

PRESENTATION The Dark Side of Suibsidies: Quantifying Contaminant Exposure to Riparian Predators Via Stream Insects 05/26/2008
WALTERS, DAVID M., K. M. FRITZ, AND R. R. Otter. The Dark Side of Suibsidies: Quantifying Contaminant Exposure to Riparian Predators Via Stream Insects. Presented at North American Benthological Society, Salt Lake City, UT, May 25 - 30, 2008.
Abstract: Aquatic insects provide a critical nutrient subsidy to riparian food webs, yet their role as vectors of contaminants to terrestrial ecosystems is poorly understood. We investigated relationships between aquatic (resource utilization) and contaminant exposure for a riparian invertivore assemblage (spiders and herptiles) along a stream contaminated with polychlorinated biphenyls (PCBs). Stable carbon and nitrogen isotopes indicated that aquatic insect utilization varied among predators, with gradual enrichment of stable carbon and depletion of nitrogen as predators shifted from aquatic to terrestrial prey.

PRESENTATION Integration of Dna Barcoding Approaches Into Aquatic Bioassessments 05/26/2008
JACKSON, S. A., M. BAGLEY, E. Friedman, I. Turcsanyi, S. Swenson, A. C. ROTH, A. Driskell, AND L. Weight. Integration of Dna Barcoding Approaches Into Aquatic Bioassessments. Presented at North American Benthological Society, Salt Lake City, UT, May 25 - 30, 2008.
Abstract: The Clean Water Act directs states to protect water resources by developing criteria based in part on biological assessments of natural aquatic ecosystems. Current protocols can be limited by the availability of taxonomic expertise and concerns about precision and accuracy in morphological identification of larval invertebrates. Integration of DNA barcodes into these protocols would provide a standardized, objective and accessible platform for taxonomic discriminations, reducing classification errors and increasing taxonomic resolution. The goal is to evaluate the cost, time and distriminatory ability associated with DNA barcoding. DNA barcodes (cytochrome oxidase I [COI] sequences) were generated for species of Ephemeroptera, Plecoptera and Trichoptera collected as part of Maryland's 2007 wadeable stream survey and added to a publically available DNA barcode database. Twenty percent of specimens subjected to an independent morphological re-identification revealed genus-level agreement of 90%. Molecular placement of DNA barcodes on a taxon ID tree showed genus-level agreement with morphology, with distinct genetic groups therein. These study results will be used to determine how to incorporate DNA barcoding into bioassessment programs to leverage morphological taxonomy and DNA barcoding approaches.

PRESENTATION Benthic Diatom Composition in Wet and Dry Isolated Forested Wetlands: Implications for Monitoring and Assessment 05/26/2008
LANE, C. R., K. C. Reiss, SUSANNA J. DECELLES, AND M. T. Brown. Benthic Diatom Composition in Wet and Dry Isolated Forested Wetlands: Implications for Monitoring and Assessment. Presented at Society of Wetland Scientists Annual Conference, Washington, DC, May 25 - 30, 2008.
Abstract: The development of bioindicators for wetlands, especially ephemerally hydrated depressional and isolated wetlands, can be problematic because of seasonal changes in hydrology and target organism biology. To determine if benthic diatoms could be used as a year-round biological indicator of wetland condition in isolated forested wetlands of Florida, eleven wetlands were sampled twice during a six-month period, once when hydrated and once when dry. Dry sites had significantly higher diatom taxa richness at genus and species levels. Non-metric multidimensional scaling and multiple response permutation process analyses resulted in no obvious or significant wet/dry grouping of abundance data. Five of seven metrics of the Florida Wetland Condition Index (FWCI) for depressional forested wetlands were significantly linearly correlated, while only one of seven metrics (a dissolved oxygen indicator) had a significantly different mean in paired t-test analyses. The final FWCI was significantly correlated betweenw et and dry sites, and no difference was found in mean FWCI score between wet and dry sites, suggesting that benthic diatoms can be used to monitor and assess wetland condition regardless of season or site hydrologic conditions.

PRESENTATION Delineating Resource Sheds in Aquatic Ecosystems (Presentation) 05/26/2008
RAIKOW, D., J. F. Atkinson, AND T. E. Croley. Delineating Resource Sheds in Aquatic Ecosystems (Presentation). Presented at North American Benthological Society, Salt Lake City, UT, May 25 - 30, 2008.
Abstract: Analysis of spatially-explicit ecological phenomena in aquatic ecosystems is impeded by a lack of knowledge of, and tools to delimit, spatial patterns of material supply to point locations. Here we apply the concept of "resource sheds" to coasts and watersheds. Resource sheds are defined as source areas from which materials are derived for an individual, population, or location, over a specified time interval. Resource shed total spatial extent, and relative contributory importance, for selected point locations in Lake Erie were delimited, including extension into the Maumee River watershed. Resource shed size and orientation varied with in-lake circulation patterns, terrestrial precipitation patterns, time interval, and season. In-lake resource sheds for sites near river mouths and along shorelines showed less variation in size and shape with time and between seasons compared with off-shore sites. Source areas within watersheds supplying water to off-shore locations were estimated by linking the output of hydrologic and hydrodynamic models.

PRESENTATION Documenting Taxonomic Data Quality for Field Fish Identifications: A Proposal for National Surveys 05/19/2008
Stribling, J. B., J. E. FLOTEMERSCH, R. M. Hughes, L. REYNOLDS, T. SMITH, B. D. Snyder, E. TARQUINIO, AND C. O. Yoder. Documenting Taxonomic Data Quality for Field Fish Identifications: A Proposal for National Surveys. Presented at Sixth National Water Quality Monitoring Council, Atlantic City, NJ, May 18 - 22, 2008.
Abstract: The U.S. Environmental Protection Agency is in the midst of a multiyear series of natinal surveys of water resource conditions. Because communicating ecological condition is the primary objective of the surveys, quantitative biological indicators are key. Thus, if raw taxonomic data (identifications and counts) used to calculate the indicators are of unknown quality, they have the potential of compromising the credibility and defensibility of the survey results. For the National Rivers and Streams Survey (NRS), fish assemblage samples will be collected from approximately 2000 river and stream sites over a 2-year period, beginning in 2008. To date, issues of taxonomic data quality for fish in biological assessments have been focused on verification of questionable specimens, that is, only for specimens the person performing the primary identifications thinks necessary. As part of the NRS, the vouchering system for the fish assemblage samples will be the species that is rare, threatened, or endangered; ubiquitous, common, and distinct; or very large-bodied. For all others, at least one specimen will be preserved to represent the species. Sample vouchers, thus, will be a combination of preserved specimens and digital images that regional experts can use to reconstruct a complete taxa list for each site. Our proposal is to have whole-sample species lists reproduced from a sample voucher by regional experts. Direct comparison of the taxa list from the voucher with that produced from the field will allow quantification of rates of differences, by sample as well as highlighting those species most frequently causing problems. This will be performed on a randomly-selected 10% of the samples for each field taxonomist. Discrepancies between the two lists will be examined, and reasons for the differences determined. Based on the comparison results, corrective actions will be developed and lead to updating of the database, and potentially, initiatives focused on training for identification of certain taxa.

PRESENTATION A Predictive Model for Anti-Degradation Monitoring of the Delaware River 05/19/2008
BLOCKSOM, K. A., J. E. FLOTEMERSCH, AND R. LIMBECK. A Predictive Model for Anti-Degradation Monitoring of the Delaware River. Presented at National Water Quality Monitoring Conference, Atlantic City, NJ, May 18 - 22, 2008.
Abstract: The non-tidal portion of the Delaware River consists of many large sections designated as Wild and Scenic Rivers and passes through two national parks. Although there is increasing pressure on the watershed, large sections of the mainstem of the river can be considered to be in minimally disturbed condition. Thus, the primary goal of this research is to develop a monitoring tool that can be used by the Delaware River Basin Commission (DRBC) to monitor for changes in the macroinvertebrate assemblage that may be a result of human development in the basin. Using the conditions in the river in 2006 as a baseline, we developed a predictive model that can be used to assess the similarity of any given site to the minimally disturbed condition as predicted by the model. We first verified the sections of river that are considered representative of minimal disturbance by the DRBC and national park personnel. We included macroinvertebrate data from riffles, glide/runs and pools in a cluster analysis. Then we performed discriminant analysis using information on substrate, velocity, depth, and sampling date to develop a RIVPACS-type predictive model for the Delaware River. This type of approach will provide the DRBC and national parks with a tool that can be of use for early detection of changes to the river and may be useful in diagnosing causes of such changes.

PRESENTATION A Review on Setting Appropriate Reach Length for Biological Assessment of Boatable Rivers 05/05/2008
FLOTEMERSCH, J. E. A Review on Setting Appropriate Reach Length for Biological Assessment of Boatable Rivers. Presented at American Fisheries Society, 2008 Western Division, Portland, OR, May 04 - 08, 2008.
Abstract: Researchers working on boatable rivers are presented with the task of selecting an appropriate stream length, or reach length, from which data will be collected. Ideally, the sampling effort applied is the minimum that will allow stated objectives to be addressed as required by a study. Comparisons based on insufficient sampling effort estimates can be confounded because real differences in assemblage structure may be indistingishable from method error. In general, long reaches are advantageous for describing the mean condition of a large river sec tion as they minimize the influence of small scale conditions and localized impairments. This advantage, however, can also be a disadvantage because long reach lengths may mask small scale habitat conditions and impairments. They may also decrease the sensitivity of indicators to detect linkages between local river conditins and drivers of conditions. Conversely, short reach lengths can be criticized for being too sensitive to local conditions and thus provide a biased reading of the overall system condition. Alternatively, reach lengths can be set by evaluating the biological parameter responses, as a function of geomorphology or a combination of the two. In short, what is deemed an appropriate reach length should be a balance between data cololection ntensity for a particular event, and the number of events that can be sampled; all of which is further tempered by carefulc onsideration of the question(s) beind addressed, the data quality (in part, the precision, accuracy and sensitivity) required to address the question, the statistical approach that will be used to analyze any resulting data, and present and future resource availability. This presentation will review issues related to appropriate sample unit definition, or sampling reach for rivers, and provide examples.

PRESENTATION Linkage of Exposure and Effects Using Genomics, Proteomics and Metabolomics in Small Fish Models (Presentation) 05/01/2008
BENCIC, D. C., A. D. BIALES, R. WANG, J. M. LAZORCHAK, T. W. COLLETTE, D. L. VILLENEUVE, G. T. ANKLEY, AND D. L. LATTIER. Linkage of Exposure and Effects Using Genomics, Proteomics and Metabolomics in Small Fish Models (Presentation). Presented at 10th Brazilian Congress of Ecotoxicology, Porto Alegre, BRAZIL, April 30 - May 03, 2008.
Abstract: This research project combines the use of whole organism endpoints, genomic, proteomic and metabolomic approaches, and computational modeling in a systems biology approach to 1) identify molecular indicators of exposure and biomarkers of effect to EDCs representing several modes/mechanisms of action (MOA), and 2) link these indicators/biomarkers to effects that are relevant for both diagnostic and predictive risk assessment susing two small fish models. The two fish species used in this project are fathead minnows (Pimephales promelas; FHMs) and zebrafish (Danio rerio; ZF). The research has been organized into three phases, with phase 1 comprising 21-day reproduction studies with FHMs and phase 2 consisting of 1-4 day studies with the same chemicals to identify MOA-specific alterations in the transcriptome, proteome, and metabolome of ZF. Microarrays followed by real-time quantitative polymerase chain reaction (QPCR) verification and two-dimensional gel polyacrylamide gel electrophoresis (2-D PAGE) followed by mass spectrometry identification have been used to detect specific transcriptional and protein patterns, respectively, resulting from exposure to EDCs. Detection of anomalies at a molelcular level enables screening methods of shorter duration to identify effects, soon after exposure, before they are manifested at the tissue-, organ-, individual-, or population-level. Phase 3 involves translating ZF results back to FHMs and linking these molecular level changes to higher order changes form phase 1. The ability to determine the changes at each step of the molecular cascade allows for more relaible interpretation of key biological processes that result in phenotypic effects and supports the development of informative and predictive indicators. Incorporation of the results into conceptual systems (HPG axis-based) and population models will help integrate all aspects of the three phases of data collection.

PRESENTATION Research to Inform Policy on Headwater Streams: Ongoing and Future Directions - Oral Presentation 05/01/2008
FRITZ, K. M. Research to Inform Policy on Headwater Streams: Ongoing and Future Directions - Oral Presentation. Presented at Southern Illinois University Zoology Department Seminar, Carbondale, IL, May 01, 2008.
Abstract: Oral presentation at Southern Illinois University, Department of Zoology, Graduate Student Association Seminar

PRESENTATION Potential Exposure to Human Prescription Pharmaceutical Residues from Wastewater 04/15/2008
KOSTICH, M., A. BATT, AND J. M. LAZORCHAK. Potential Exposure to Human Prescription Pharmaceutical Residues from Wastewater. Presented at Toxicology and Risk Assessment Conference, West Chester, OH, April 15, 2008.
Abstract: Pharmaceuticals in the environment (PiE) pose a complicated problem, involving multiple dissimilar compounds, multiple routes of potential exposure, and a range of potentially affected organisms that span the tree of life. Key uncertainties include not knowing which of the thousands of available active pharmaceutical ingredients (APIs) to study, uncertainties about the most significant routes of human or ecological exposure, and (for ecotoxicology) identifying susceptible species. Our research to date has focused on a broad class of pharmaceuticals frequently discussed in the PiE context (human prescription pharmaceuticals) introduced into the environment via a frequently cited PiE source (municipal wastewater effluents). We have used published marketing data and wastewater production rates to predict the maximum likely wastewater concentration (PEC) of each of 400 top-selling APIs potentially entering the environment each year. APIs were prioritized for monitoring based on their PEC's projected potential to affect human biology, inhibit microbial growth, or affect other organisms. Chemical monitoring studies, which are currently underway, will be used to refine the model-based risk estimates, and select APIs for toxicological investigation under environmentally relevant conditions. We have examined the conservation of molecular drug targets across the tree of life in order to nominate taxa which might be affected by low-level API exposure.

PRESENTATION Aquatic Risks Posed By Pharmaceutical Use 04/15/2008
KOSTICH, M. Aquatic Risks Posed By Pharmaceutical Use. Presented at Toxicology and Risk Assessment Conference, West Chester, OH, April 15, 2008.
Abstract: Oral presentation at the Toxicology and Risk Assessment Conference 2008.

PRESENTATION Seldi Proteinchip-Based Liver Biomarkers in Fungicide Exposed Zebrafish 03/17/2008
BULMAN, A., D. C. BENCIC, A. D. BIALES, R. W. FLICK, G. ROSS, AND D. L. LATTIER. Seldi Proteinchip-Based Liver Biomarkers in Fungicide Exposed Zebrafish. Presented at Society of Toxicology, Seattle, WA, March 16 - 20, 2008.
Abstract: The research presented here is part of a three-phased small fish computational toxicology project using a combination of 1) whole organism endpoints, 2) genomic, proteomic, and metabolomic approaches, and 3) computational modeling to (a) identify new molecular biomarkers of exposure to endocrine disrupting compounds (EDCs) representing several modes of action (MOA) and (b) link these biomarkers to effects that are relevant for both diagnostic and predictive risk assessments. The effects of prochloraz (PCZ) on reproductively mature male and female zebrafish were examined following 48 h continuous exposure in a flow-through system to control (water only), low (100 µg/l), and high (500 µg/l) doses. PCZ is an imidazole fungicide used to protect food crops by weakening fungal cell membranes through CYP51 inhibition. PCZ is known to have a mixed MOA in vertebrates, functioning as an aromatase (CYP19) inhibitor as well as an androgen receptor antagonist. Zebrafish liver lysates were profiled on three SELDI ProteinChip array types (weak cation exchange, strong anion exchange, and metal affinity), focusing on the 1.5 kDa to 25 kDa mass range. Over 300 individual m/z peak clusters were analyzed across the six sample groups (n=8 each). Gender related protein expression differences (p<0.05) were observed, with a majority of these markers exhibiting higher expression in males. Both up- and down-regulated markers were detected upon PCZ exposure. PCZ response in the females was observed primarily as up-regulation of candidate markers; in contrast, considerably more changes, primarily down-regulation of candidate markers, were observed in males. These differential expression profiles will be used to help identify new molecular biomarkers of exposure and integration of these data with whole organism endpoints will provide more definitive description of the mixed MOA of PCZ.

PUBLISHED REPORT Prevalence of Tumors in Brown Bullhead from Three Lakes in Southeastern Massachusetts, 2002 12/31/2008
Baumann, P. C., D. R. LeBlanc, V. S. Blazer, J. R. MEIER, S. T. Hurley, AND Y. Kiryu. Prevalence of Tumors in Brown Bullhead from Three Lakes in Southeastern Massachusetts, 2002. U.S. Geological Survey, Washington, DC, 2008.
Abstract: The Massachusetts Military Reservation (MMR) has been a military base on western Cape Cod since the early 1900s. Contaminated surface water and ground water from the MMR have discharged into several kettle lakes on or near the base.

 

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