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Sample records for lepomis macrochirus rafinesque

  1. Toxicity of 19 adjuvants to juvenile Lepomis macrochirus (bluegill sunfish).

    Science.gov (United States)

    Haller, William T; Stocker, Randall K

    2003-03-01

    Nineteen adjuvants, many used as surfactants for aquatic herbicide applications, were applied in static bioassay to bluegill sunfish (Lepomis macrochirus) for 96 h to determine median lethal concentrations (LC50). Surfactants are added to the tank mix as a percentage (v/v) of the total volume, in contrast to herbicide application rates, which are usually expressed in kilograms per hectare. Two ethoxylated tallow amine products were the most toxic, having LC50 values of 1.6 and 2.9 ppm (all values v/v). Seven alcohol/glycol-based surfactants had 96-h LC50 values of 4.0 to 11.6 ppm (mean = 7.9 ppm). The polysiloxane- or silicone-based surfactants had toxicities of 18.1 to 29.7 ppm (mean = 24.7). Two limonene-based products had LC50 values of 10.2 and 30.2 ppm. A methylated seed oil with emulsifier had a LC50 of 53.1 ppm. Two acid/buffer utility adjuvants had LC50 values of 60.8 and 221 ppm. To compare the relative safety of the tested surfactants, we assumed maximum label rate applications to 1 m deep water with uniform mixing. This comparison of relative safety is based on mortality to 50% of the test organisms and does not imply application rates that would not result in any mortality. The two ethoxylated tallow amines, neither used or recommended for aquatic applications, had a relative safety factor of 12.6 or less. Relative safety factor varied from 6.2 to 20.4 for the seven alcohol/glycol surfactants, 38.4 to 63.2 for silicone-based products, 5.5 to 16.1 for limonene products, 113 for methylated seed oil, and 132.2 to 315.7 for acid/buffer utility adjuvants. When used according to label recommendations under normal use conditions, these adjuvants should not be present in acutely toxic concentrations; however, the most toxic adjuvants in very shallow water (< 10 cm) would be toxic to bluegill sunfish that did not move to deeper water to avoid lethal concentrations.

  2. Growth, life history, and species interactions of bluegill sunfish (Lepomis macrochirus) under heavy predation

    Energy Technology Data Exchange (ETDEWEB)

    Belk, Mark Carl [Univ. of Georgia, Athens, GA (United States)

    1992-01-01

    The purpose of this study was, first, to compare growth and life history characteristics of an unfished population of bluegill sunfish (Lepomis macrochirus) in the presence of an abundant predator population to characteristic exhibited by bluegills in typical southeastern US reservoirs where the abundance of predators is reduced, but fishing is increased. The second objective was to determine if differences observed between populations were determined genetically or environmentally.

  3. Toxicity and bioaccumulation of waterborne and dietary selenium in juvenile bluegill (Lepomis macrochirus)

    Science.gov (United States)

    Cleveland, Laverne; Little, Edward E.; Buckler, Denny R.; Wiedmeyer, Raymond H.

    1993-01-01

    Juvenile bluegill (Lepomis macrochirus) were exposed to waterborne selenium as a 6:1 mixture of selenate to selenite (as Se) for 60 d and to dietary seleno-l-methionine for 90 d. Measured concentrations of total selenium in the waterborne exposure ranged from 0.16 to 2.8 mg/l, and concentrations of seleno-l-methionine in the test diet ranged from 2.3 to 25.0 mg/kg wet weight. Mortality, body weight, condition factor, swimming and feeding behavior, aggression, and selenium tissue residues were monitored during the tests. Increased mortality at measured concentrations of 0.64 mg Se/l and greater was the primary adverse effect of waterborne selenium on the juvenile bluegill. Bluegill exposed to 2.8 mg/l of waterborne Se for 30 d exhibited a significant reduction in condition factor (K), whereas dietary exposure of bluegill to 25 mg Se/kg for 30 d and 13 mg Se/kg or greater for 90 d elicited significant reductions in K. Mortality and swimming activity of bluegill were not affected in the dietary exposure. Net accumulation of Se from both water and diet was directly related to exposure concentration. Bioconcentration factors ranged from 5 to 7 for bluegill exposed to waterborne Se and from 0.5 to 1.0 for fish exposed to dietary Se. Results of these laboratory tests indicate that survival of bluegill may be impaired in natural waters with elevated Se concentrations.

  4. Determination of ten perfluorinated compounds in bluegill sunfish (Lepomis macrochirus) fillets

    Energy Technology Data Exchange (ETDEWEB)

    Delinsky, Amy D.; Strynar, Mark J. [US Environmental Protection Agency, NERL, Research Triangle Park, NC 27711 (United States); Nakayama, Shoji F. [US Environmental Protection Agency, NRMRL, Cincinnatti, OH (United States); Varns, Jerry L. [NCBA Inc., SEE program, Durham, NC (United States); Ye, XiBiao [NIEHS, IRTA Fellow, Research Triangle Park, NC (United States); McCann, Patricia J. [Minnesota Department of Health, St. Paul, MN (United States); Lindstrom, Andrew B., E-mail: lindstrom.andrew@epa.gov [US Environmental Protection Agency, NERL, Research Triangle Park, NC 27711 (United States)

    2009-11-15

    A rigorous solid phase extraction/liquid chromatography/tandem mass spectrometry method for the measurement of 10 perfluorinated compounds (PFCs) in fish fillets is described and applied to fillets of bluegill sunfish (Lepomis macrochirus) collected from selected areas of Minnesota and North Carolina. The 4 PFC analytes routinely detected in bluegill fillets were perfluorooctane sulfonate (PFOS), perfluorodecanoic acid (C10), perfluoroundecanoic acid (C11), and perflurododecanoic acid (C12). Measures of method accuracy and precision for these compounds showed that calculated concentrations of PFCs in spiked samples differed by less than 20% from their theoretical values and that the %RSD for repeated measurements was less than 20%. Minnesota samples were collected from areas of the Mississippi River near historical PFC sources, from the St. Croix River as a background site, and from Lake Calhoun, which has no documented PFC sources. PFOS was the most prevalent PFC found in the Minnesota samples, with median concentrations of 47.0-102 ng/g at locations along the Mississippi River, 2.08 ng/g in the St. Croix River, and 275 ng/g in Lake Calhoun. North Carolina samples were collected from two rivers with no known historical PFC sources. PFOS was the predominant analyte in fish taken from the Haw and Deep Rivers, with median concentrations of 30.3 and 62.2 ng/g, respectively. Concentrations of C10, C11, and C12 in NC samples were among the highest reported in the literature, with respective median values of 9.08, 23.9, and 6.60 ng/g in fish from the Haw River and 2.90, 9.15, and 3.46 ng/g in fish from the Deep River. These results suggest that PFC contamination in freshwater fish may not be limited to areas with known historical PFC inputs.

  5. Examining the joint toxicity of chlorpyrifos and atrazine in the aquatic species: Lepomis macrochirus, Pimephales promelas and Chironomus tentans

    Energy Technology Data Exchange (ETDEWEB)

    Tyler Mehler, W.; Schuler, Lance J. [Fisheries and Illinois Aquaculture Center and Department of Zoology, Southern Illinois University at Carbondale, Carbondale, IL 62901-6511 (United States); Lydy, Michael J. [Fisheries and Illinois Aquaculture Center and Department of Zoology, Southern Illinois University at Carbondale, Carbondale, IL 62901-6511 (United States)], E-mail: mlydy@siu.edu

    2008-03-15

    The joint toxicity of chlorpyrifos and atrazine was compared to that of chlorpyrifos alone to discern any greater than additive response using both acute toxicity testing and whole-body residue analysis. In addition, acetylcholinesterase (AChE) inhibition and biotransformation were investigated to evaluate the toxic mode of action of chlorpyrifos in the presence of atrazine. The joint toxicity of atrazine and chlorpyrifos exhibited no significant difference in Lepomis macrochirus compared to chlorpyrifos alone; while studies performed with Pimephales promelas and Chironomus tentans, did show significant differences. AChE activity and biotransformation showed no significant differences between the joint toxicity of atrazine and chlorpyrifos and that of chlorpyrifos alone. From the data collected, the combination of atrazine and chlorpyrifos pose little additional risk than that of chlorpyrifos alone to the tested fish species. - The joint toxicity between atrazine and chlorpyrifos caused greater than additive responses in invertebrates, but the interactions in vertebrates was less pronounced.

  6. Examining the joint toxicity of chlorpyrifos and atrazine in the aquatic species: Lepomis macrochirus, Pimephales promelas and Chironomus tentans

    International Nuclear Information System (INIS)

    Tyler Mehler, W.; Schuler, Lance J.; Lydy, Michael J.

    2008-01-01

    The joint toxicity of chlorpyrifos and atrazine was compared to that of chlorpyrifos alone to discern any greater than additive response using both acute toxicity testing and whole-body residue analysis. In addition, acetylcholinesterase (AChE) inhibition and biotransformation were investigated to evaluate the toxic mode of action of chlorpyrifos in the presence of atrazine. The joint toxicity of atrazine and chlorpyrifos exhibited no significant difference in Lepomis macrochirus compared to chlorpyrifos alone; while studies performed with Pimephales promelas and Chironomus tentans, did show significant differences. AChE activity and biotransformation showed no significant differences between the joint toxicity of atrazine and chlorpyrifos and that of chlorpyrifos alone. From the data collected, the combination of atrazine and chlorpyrifos pose little additional risk than that of chlorpyrifos alone to the tested fish species. - The joint toxicity between atrazine and chlorpyrifos caused greater than additive responses in invertebrates, but the interactions in vertebrates was less pronounced

  7. Testing a bioenergetics-based habitat choice model: bluegill (Lepomis macrochirus) responses to food availability and temperature

    Science.gov (United States)

    2011-01-01

    Using an automated shuttlebox system, we conducted patch choice experiments with 32, 8–12 g bluegill sunfish (Lepomis macrochirus) to test a behavioral energetics hypothesis of habitat choice. When patch temperature and food levels were held constant within patches but different between patches, we expected bluegill to choose patches that maximized growth based on the bioenergetic integration of food and temperature as predicted by a bioenergetics model. Alternative hypotheses were that bluegill may choose patches based only on food (optimal foraging) or temperature (behavioral thermoregulation). The behavioral energetics hypothesis was not a good predictor of short-term (from minutes to weeks) patch choice by bluegill; the behavioral thermoregulation hypothesis was the best predictor. In the short-term, food and temperature appeared to affect patch choice hierarchically; temperature was more important, although food can alter temperature preference during feeding periods. Over a 19-d experiment, mean temperatures occupied by fish offered low rations did decline as predicted by the behavioral energetics hypothesis, but the decline was less than 1.0 °C as opposed to a possible 5 °C decline. A short-term, bioenergetic response to food and temperature may be precluded by physiological costs of acclimation not considered explicitly in the behavioral energetics hypothesis.

  8. Population biology of bluegills, Lepomis macrochirus, in lotic habitats on the irrigated San Joaquin Valley floor

    Science.gov (United States)

    Saiki, M.K.; Schmitt, C.J.

    1985-01-01

    Rapid expansion of irrigated agriculture in the western United States has prompted concerns for aquatic resources. Although the impacts of irrigation activities on quality and quantity of river water are well documented (e.g., high turbidity from soil erosion, eutrophication from nutrient runoff, pesticide contamination, reduced dis- charge), their effects on fish populations are still poorly understood. We studied the food, growth, and relative weight (a measure of body condition) of bluegills, Lepo- mis macrochirus, in relation to environmental factors in reaches of the San Joaquin and Merced rivers that have been affected to varying degrees by irrigation return flows. Fry of bluegills ate mostly cladocerans and copepods; fingerlings and larger fish ate immature aquatic insects, terrestrial insects, amphipods, and mollusks. Bluegill stomachs were fuller and contained a higher diversity of forage taxa in habitats with low turbidity and conductivity, weak buffering capacity, and low nutrient levels; bluegills also ate a more diverse diet where the potential forage supply (benthic macroinvertebrates) was most diverse. Bluegills attained mean total lengths of about 42 mm at age I, 86 mm at age 11, 116 mm at age III, 153 mm at age IV, and 166 mm at age V. Mean relative weight ranged from 96-111. Growth rate and relative weight were not significantly correlated with environmental or dietary variables. On the basis of our study, we concluded that environmental degradation from irrigation activities affected the diet of bluegills primarily by modifying the food supply, but growth rate and body condition were not affected.

  9. Bioaccumulation factor for 32P measured in bluegill, Lepomis macrochirus, and catfish, Ictalurus punctatus

    International Nuclear Information System (INIS)

    Kahn, B.; Turgeon, K.S.; Martini, D.K.; Dunkerly, S.J.; el-Shinawy, R.M.; Wilson, M.D.

    1987-01-01

    The ratio of the bioaccumulation factors for 32 P and phosphorus was determined for edible tissue in two species of freshwater fish by measuring the specific activity ( 32 P activity per milligram phosphorus) in muscle relative to feed. The 32 P tracer was added to the feed at a uniform level throughout the study. Feeding was at two levels: ad libitum and at a lower but constant intake per body weight. In the main experiment, bluegill were maintained in a large flow-through tank and sacrificed at approximately weekly intervals for 51 d of 32 P accumulation and 28 d of depuration to compare the specific activity with values predicted with a calculational model. In experiments performed in smaller aquaria, the specific activity in bluegill and catfish muscle was compared at two feeding levels and two temperatures. In addition, unfed fish were exposed to 32 P in water at a known specific activity to determine the extent of phosphorus uptake directly from water. The pattern of specific activity increase and decrease in fish muscle during the accumulation/depuration experiment was consistent with a one-compartment model, so that specific activity ratios at steady state could be predicted from measurements during relatively brief exposures. On this basis, the ratio of the bioaccumulation factors of 32 P and phosphorus in fish feeding ad libitum was 0.081 for bluegill and 0.17 for catfish. Hence, at a mean phosphorus bioaccumulation factor of 70,000, the factors for 32 P are 6000 and 12,000, respectively. The ratios were less at lower phosphorus intakes associated with lower feeding rates; moreover, the lesser value for bluegill occurred at a much lower phosphorus intake than by catfish

  10. BEHAVIORAL AND PHYSIOLOGICAL RESPONSES OF DAPHNIA MAGNA, CHLORELLA VULGARIS, LEPOMIS MACROCHIRUS, AND VIBRIO FISCHERI TO TOLUENE

    Science.gov (United States)

    The research presented here is a continuation of work designed to further the science of available and developing online toxicity monitors(OTMs) and how they may be most effectively deployed in a watershed management plan and/or water quality early warning system. Source waters o...

  11. BEHAVIORAL AND PHYSIOLOGICAL RESPONSES OF DAPHNIA MAGNA, CHLORELLA VULGARIS, CORBICULA FLUMINEA, LEPOMIS MACROCHIRUS, AND VIBRO FISCHERI

    Science.gov (United States)

    The research presented here is a continuation of work designed to further the science of available and developing continuous, automated water quality monitors and how they may be most effectively deployed in a watershed management plan and/or water quality early warning system (W...

  12. Uptake of 3H-cAMP by retinal pigment epithelium isolated from bluegill sunfish (Lepomis macrochirus

    Directory of Open Access Journals (Sweden)

    Moredock Steve

    2006-12-01

    Full Text Available Abstract Background In bluegill sunfish, the melanin-containing pigment granules of the retinal pigment epithelium undergo cyclic movements in response both to ambient lighting and circadian cues. Pigment granules aggregate into the cell body at night (in the dark, and disperse into apical processes during the day (in the light. Regulation of pigment granule aggregation in a number of fishes depends on modulating the intracellular levels of cyclic adenosine monophosphate. Results Here we show isolated RPE takes up cyclic adenosine monophosphate (cAMP in a saturable manner, exogenously applied cAMP induces pigment granule aggregation in retinal pigment epithelium isolated from bluegill, and aggregation induced in this manner is inhibited by treatment with probenecid, an organic anion transport inhibitor. Conclusion Our results raise the possibility that cAMP functions as a messenger secreted from the neural retina to signal darkness to the RPE, which takes it up. It further suggests that organic anion transport systems are the route by which cAMP crosses RPE cell membranes since probenecid inhibits extracellular cAMP from causing pigment granule aggregation.

  13. BEHAVIORAL AND PHYSIOLOGICAL RESPONSES OF DAPHNIA MAGNA, CHLORELLA VULGARIS, CORBICULA FLUMINEA, AND LEPOMIS MACROCHIRUS TO COPPER AND CYANIDE

    Science.gov (United States)

    The research presented here was designed to further the science of available and developing continuous, automated water quality monitors and how they may be most effectively deployed in a watershed management plan and/or water quality early warning system (WQEWS). Source waters ...

  14. Histopathologic evaluation of postmortem autolytic changes in bluegill (Lepomis macrohirus and crappie (Pomoxis anularis at varied time intervals and storage temperatures

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    Jami George

    2016-04-01

    Full Text Available Information is lacking on preserving fish carcasses to minimize postmortem autolysis artifacts when a necropsy cannot be performed immediately. The purpose of this study was to qualitatively identify and score histologic postmortem changes in two species of freshwater fish (bluegill—Lepomis macrochirus; crappie—Pomoxis annularis, at varied time intervals and storage temperatures, to assess the histologic quality of collected samples. A pooled sample of 36 mix sex individuals of healthy bluegill and crappie were euthanized, stored either at room temperature, refrigerated at 4 °C, or frozen at −20 °C, and then necropsied at 0, 4, 24, and 48 h intervals. Histologic specimens were evaluated by light microscopy. Data showed that immediate harvesting of fresh samples provides the best quality and refrigeration would be the preferred method of storage if sample collection had to be delayed for up to 24 h. When sample collection must be delayed more than 24 h, the preferred method of storage to minimize autolysis artifacts is freezing if evaluation of the gastrointestinal tract is most important, or refrigeration if gill histology is most important. The gill arch, intestinal tract, followed by the liver and kidney were the most sensitive organs to autolysis.

  15. Myxobolus lepomis n. sp. (Cnidaria: Myxobolidae), a gill myxozoan infecting Lepomis marginatus Holbrook and Lepomis miniatus Jordan (Perciformes: Centrarchidae), in the Big Thicket National Preserve, Texas, USA.

    Science.gov (United States)

    Rosser, Thomas G; Baumgartner, Wes A; Barger, Michael A; Griffin, Matt J

    2017-05-01

    A parasitological survey of freshwater fishes in the Big Thicket National Preserve in southeast Texas revealed myxozoan infections in two species of sunfish, Lepomis marginatus Holbrook and Lepomis miniatus Jordan (Perciformes: Centrarchidae). Pseudocysts were elongate-oval, 988 × 485 µm (ex L. marginatus) and 800 × 606 µm (ex L. miniatus) and demonstrated a predilection to the edge of the primary gill lamellae. Myxospores consistent with the genus Myxobolus were oblong, 16.8-21.3 (19.0 ± 0.9) µm long, 7.0-8.8 (7.9 ± 0.5) µm wide and 5.3-6.1 (5.8 ± 0.3) µm thick (ex L. marginatus) and 17.2-20.3 (18.8 ± 0.7) µm long, 7.5-9.9 (8.7 ± 0.6) µm wide, and 6.8-7.2 (7.0 ± 0.2) µm thick (ex L. miniatus); with 2 pyriform polar capsules 8.3-9.8 (9.0 ± 0.5) µm long, 2.2-2.7 (2.5 ± 0.2) µm wide (ex L. marginatus) and 9.2-10.5 (10.0 ± 0.4) µm long, 2.2-3.0 (2.8 ± 0.2) µm wide (ex L. miniatus). Statistically, the measurements of spore body width, polar capsule length, and polar capsule width were significantly different between myxospores from L. marginatus and L. miniatus. However, intraspecific genetic variability between isolates at the 18S rRNA gene was negligible, with 2,000 bp of sequence. The isolates shared no significant sequence similarity with any myxozoan deposited in the GenBank nucleotide database. Phylogenetic analysis inferred from the 18S rRNA gene from both L. marginatus and L. miniatus placed the isolates within a clade of myxozoan parasites of perciform fishes. Based on shared tissue and host family tropism, overlapping morphological characters and high degrees of sequence conservation at the 18S rRNA gene, we propose these isolates as morphologically distinct, genetically conspecific representatives of M. lepomis n. sp. from the gills of L. marginatus and L. miniatus in the Big Thicket National Preserve in Texas, USA.

  16. Notes on the Diet of Reproductively Active Male Rafinesque's Big Eared Bats

    International Nuclear Information System (INIS)

    Menzel, M.A.; Carter, T.C.; Menzel, J.M.; Edwards, J.W.; Ford, W.M.

    2002-01-01

    Diet examination through the use of fecal samples, of five reproductively active male Rafinesque's big-eared bats from the Upper Coastal Plain of South Carolina during August and September 1999. Diets of these individuals in upland pine stands were similar to diets of Rafinesque's big-eared bats in bottomland and upland hardwood habitats. Although fecal samples had three insect orders, the diet consisted primarily of lepidopterans

  17. Pranked by Audubon: Constantine S. Rafinesque's description of John James Audubon's imaginary Kentucky mammals

    Science.gov (United States)

    Woodman, Neal

    2016-01-01

    The North American naturalist Constantine S. Rafinesque spent much of the year 1818 engaged in a solo journey down the Ohio River Valley to explore parts of what was then the western United States. Along the way, he visited a number of fellow naturalists, and he spent more than a week at the Henderson, Kentucky, home of artist and ornithologist John James Audubon. During the succeeding two years, Rafinesque published descriptions of new species that resulted from his expedition, including eleven species of fishes that eventually proved to have been invented by Audubon as a prank on the credulous naturalist. Less well known are a number of “wild rats” described by Rafinesque that include one recognized species (Musculus leucopus) and ten other, imaginary “species” fabricated by Audubon (Gerbillus leonurus, G. megalops, Spalax trivittata, Cricetus fasciatus, Sorex cerulescens, S. melanotis, Musculus nigricans, Lemmus albovittatus, L. talpoides, Sciurus ruber). Rafinesque's unpublished sketches of these animals provide important insight regarding the supposed nature of the animals invented by Audubon and ultimately published by Rafinesque.

  18. Parental care compromises feeding in the pumpkinseed ( Lepomis gibbosus)

    Science.gov (United States)

    Zięba, G.; Dukowska, M.; Przybylski, M.; Fox, M. G.; Smith, C.

    2018-04-01

    Providing parental care is potentially costly. Costs can arise through elevated energy expenditure or from an increased risk of mortality. A cost of parental care can also occur because a parent is compromised in their ability to forage. We used pumpkinseed Lepomis gibbosus, a fish with an alternative male mating strategy, to test whether parental males differed in their feeding in comparison with females and cuckolder males. To address this question, we examined the stomach contents of female, cuckolder male, and parental male pumpkinseed during the breeding season over an entire diel cycle. We showed that parental males had a lower total weight of food in their stomachs in comparison with females, while cuckolder males did not. Parental males also had a lower weight and number of chironomids in their stomachs. The temporal pattern of feeding of parental males diverged from that of females, and they had a lower probability of pupal chironomids in their stomachs, which implies spatial segregation in foraging. Parental males had a greater probability of conspecific eggs in their stomachs than females, while the probability of egg cannibalism did not differ between cuckolder males and females. Overall, these finding meet predictions in accordance with an assumption that parental care and territoriality can compromise feeding.

  19. [Partial purification of peptides present in the Tityus macrochirus (Buthidae) scorpion venom and preliminary assessment of their cytotoxicity].

    Science.gov (United States)

    Rincón-Cortés, Clara Andrea; Reyes-Montaño, Edgar Antonio; Vega-Castro, Nohora Angélica

    2017-06-01

    Scorpion venom contains peptides with neurotoxic action primarily active on ion channels in the nervous system of insects and mammals. They are also characterized as cytolytic and anticancer, biological characteristics that have not yet been reported for the Tityus macrochirus venom. To assess if the total T. macrochirus venom and the fraction of partially purified peptides decrease the viability of various tumor-derived cell lines. The scorpion venom was collected by electrical stimulation and, subsequently, subjected to chromatography, electrophoresis, and ultrafiltration with Amicon Ultra 0.5® membranes for the partial identification and purification of its peptides. The cytotoxic activity of the venom and the peptides fraction trials on tumor-derived cell lines were carried out by the MTT method. The T. macrochirus scorpion venom has peptides with molecular weights ranging between 3 and 10 kDa. They were partially purified using the ultrafiltration technique, and assessed by the RP-HPLC method. Cytotoxicity trials with the whole T. macrochirus venom showed a higher viability decrease on the PC3 cell line compared to the other cell lines assessed, while the partially purified peptides decreased the HeLa cell line viability. Peptides in the T. macrochirus scorpion venom showed cytotoxic activity on some tumorderived cell lines. We observed some degree of selectivity against other cell lines assessed.

  20. Frequent arousals from winter torpor in Rafinesque's big-eared bat (Corynorhinus rafinesquii.

    Directory of Open Access Journals (Sweden)

    Joseph S Johnson

    Full Text Available Extensive use of torpor is a common winter survival strategy among bats; however, data comparing various torpor behaviors among species are scarce. Winter torpor behaviors are likely to vary among species with different physiologies and species inhabiting different regional climates. Understanding these differences may be important in identifying differing susceptibilities of species to white-nose syndrome (WNS in North America. We fitted 24 Rafinesque's big-eared bats (Corynorhinus rafinesquii with temperature-sensitive radio-transmitters, and monitored 128 PIT-tagged big-eared bats, during the winter months of 2010 to 2012. We tested the hypothesis that Rafinesque's big-eared bats use torpor less often than values reported for other North American cave-hibernators. Additionally, we tested the hypothesis that Rafinesque's big-eared bats arouse on winter nights more suitable for nocturnal foraging. Radio-tagged bats used short (2.4 d ± 0.3 (SE, shallow (13.9°C ± 0.6 torpor bouts and switched roosts every 4.1 d ± 0.6. Probability of arousal from torpor increased linearly with ambient temperature at sunset (P<0.0001, and 83% (n=86 of arousals occurred within 1 hr of sunset. Activity of PIT-tagged bats at an artificial maternity/hibernaculum roost between November and March was positively correlated with ambient temperature at sunset (P<0.0001, with males more active at the roost than females. These data show Rafinesque's big-eared bat is a shallow hibernator and is relatively active during winter. We hypothesize that winter activity patterns provide Corynorhinus species with an ecological and physiological defense against the fungus causing WNS, and that these bats may be better suited to withstand fungal infection than other cave-hibernating bat species in eastern North America.

  1. С. S. Rafinesque as a carcinologist : an annotated compilation of the information on Crustacea contained in the works of that author

    NARCIS (Netherlands)

    Holthuis, L.B.

    1954-01-01

    I. INTRODUCTION In the last tens of years more and more attention has been paid to the much neglected and ignored publications written by the eccentric early American naturalist Constantine Samuel Rafinesque. Until now, however, Rafinesque's work in the field of carcinology has received but little

  2. Taxonomy and biogeography of African fruit bats (Mammalia, Megachiroptera). 3. The genera Scotonycteris Matschie, 1894, Casinycteris Thomas, 1910, Pteropus Brisson, 1762, and Eidolon Rafinesque, 1815

    NARCIS (Netherlands)

    Bergmans, Wim

    1990-01-01

    The genera Scotonycteris Matschie, 1894, Casinycteris Thomas, 1910, Pteropus Brisson, 1762 and Eidolon Rafinesque, 1815 are characterized. An effort is made to assess the possible relationship between the genera Scotonycteris and Casinycteris. Within Scotonycteris zenkeri Matschie, 1894 a number of

  3. Substrate choice of territorial male topeka shiners (notropis topeka) in the absence of sunfish (lepomis sp.)

    Science.gov (United States)

    Witte, C.C.; Wildhaber, M.L.; Arab, A.; Noltie, Douglas B.

    2009-01-01

    Topeka shiners (Notropis topeka), an endangered minnow species, typically spawn on or around breeding Lepomis sunfish (Centrarchidae) nests. Why spawning Topeka shiners are attracted to these nests is unclear, but having the nesting sunfish provide shiner eggs with improved aeration, a lessening of siltation, and protection from egg predators are possibilities. We tested the substrate utilisation of Topeka shiners in outdoor tanks in the absence of sunfish to determine the shiner's fundamental choice. Shiners were provided with substrate patches of cleaned sand, small gravel, large gravel, and small cobble, and the bare floor of the tank. The substrate above which a male shiner established his territory was used as evidence of choice. A statistically significant choice for sand substrates was demonstrated. This fundamental choice might influence which sunfish nests Topeka shiners use, given that nest substrate characteristics differ both between sunfish species and within species by spawning site location. ?? 2009 John Wiley & Sons A/S.

  4. The distribution and contaminant exposure of Rafinesque's Big-Eared Bats in South Carolina with an emphasis on bridge surveys.

    Energy Technology Data Exchange (ETDEWEB)

    F.M. Bennett; S.C. Loeb; W.W. Bowerman

    2003-10-23

    Rafinesque's big-eared bat (Corynorhinus rafinesquii), an insectivorous mammal indigenous to the southern United States, has long been referred to as one of the least known bats in North America. Although there has been a moderate increase in the number of peer-reviewed articles published on this species in the past 6 years, the basic ecology and status of Rafinesque's big-eared bat remains largely obscure. Prior to 1996, when the United States Fish and Wildlife Service (USFWS) discontinued the list of Candidate Species, Rafinesque's big-eared bat was listed as a Federal Category 2 Candidate species. Currently, Rafinesque's big-eared bat is recognized as a ''species of special concern'' across most of its range but receives no legal protection. Nonetheless, the USFWS and numerous state agencies remain concerned about this species. Further biological research and field study are needed to resolve the conservation status of this taxona. In response to the paucity of information regarding the status and distribution of Rafinesque's big-eared bat, statewide survey of highway bridges used as roost sites was conducted.

  5. Uptake and distribution of technetium-99 by channel catfish Ictalarus punctatus (Rafinesque)

    International Nuclear Information System (INIS)

    Castro, H.T.

    1975-01-01

    An investigation was undertaken to study the uptake and distribution of Tc-99 by channel catfish Ictalarus punctatus (Rafinesque) under laboratory conditions. The major source of the radionuclide was water and not food. Fifty-four small fish (18--21 grams) were exposed to the radionuclide in groups of six in each one of nine to 20 gallon glass tanks containing a Tc-99 concentration of 0.00645 +- 0.0002 μCi/ml. The water temperature remained relatively constant at a value of 19.62 +- 0.27 0 C. The exposure times were 2 hours, 8 hours, 1, 2, 4, 6, 10, 15, and 20 days for the nine groups of fish. Three fish from each tank were separated to be processed as whole body specimens and three were dissected for muscle, skin, gills, gastrointestinal tract, liver, and kidney. All samples were homogenized using a laboratory blender and digested in preparation for analysis, using perchloric acid (70%) and hydrogen peroxide (30%), at a temperature of 70 0 C for 30 minutes. Water samples were also collected for radioassay. The analytical technique used in this study was internal liquid scintillation spectrometry. The uptake data were expressed as dpm/g and also as a concentration factor. Statistical analysis indicated significant increase in the radionuclide concentration in fish tissue with time. Statistically significant differences were also observed in the uptake among the different organs at a given time. The lowest concentration factor was achieved by the muscle followed by the skin, gills, kidney, gastrointestinal tract, and liver with the highest

  6. Reproduction of the non-native fish Lepomis gibbosus (Perciformes: Centrarchidae in Brazil

    Directory of Open Access Journals (Sweden)

    Rangel E. Santos

    2012-09-01

    Full Text Available Minas Gerais is the fourth largest Brazilian state, and has an estimate of 354 native fish species. However, these fish species may be threatened, as this state has the highest rank of fish introductions reported for Brazil and South America. As one from the total of 85 non-native species detected, Lepomis gibbosus was introduced in the 60s to serve both as foragefish and to improve sport fishing. In this study, we evaluated the establishment of L. gibbosus in a shallow lake in the city of Ouro Preto, Doce River basin, state of Minas Gerais, Southeastern Brazil. We collected fish with fishing rods every two months from March 2002-February 2003. Fragments of gonads from a total of 226 females and 226 males were obtained and processed following standard histological techniques; then 5-7μm thickness sections were taken and stained in hematoxylin-eosin. Besides, for each specimen, the biometric measurements included the standard length (SL and body weight (BW; and the sex ratio was obtained. The reproductive cycle stages were confirmed by the distribution of oocytes and spermatogenic cells. The type of spawning was determined by the frequency distribution of the reproductive cycle stages and ovarian histology. Based on the microscopic characteristics of the gonads, the following stages of the reproductive cycle were determined: one=Rest, two=Mature, three=Spawned for females or Spent for males; males and females in reproduction were found throughout the study period. Post-spawned ovaries containing oocytes in stages one (initial perinucleolar, two (advanced perinucleolar, three (pre-vitellogenic, four (vitellogenic and post-ovulatory follicles indicated fractionated-type spawning in this species. The smallest breeding male and female measured were 4.6 and 4.9cm standard length, respectively, suggesting stunting. The sex ratio did not vary between males and females along the year and bimonthly, being 1:1. Moreover, L. gibbosus appears to be at stage

  7. Reproduction of the non-native fish Lepomis gibbosus (Perciformes: Centrarchidae in Brazil

    Directory of Open Access Journals (Sweden)

    Rangel E. Santos

    2012-09-01

    Full Text Available Minas Gerais is the fourth largest Brazilian state, and has an estimate of 354 native fish species. However, these fish species may be threatened, as this state has the highest rank of fish introductions reported for Brazil and South America. As one from the total of 85 non-native species detected, Lepomis gibbosus was introduced in the 60s to serve both as foragefish and to improve sport fishing. In this study, we evaluated the establishment of L. gibbosus in a shallow lake in the city of Ouro Preto, Doce River basin, state of Minas Gerais, Southeastern Brazil. We collected fish with fishing rods every two months from March 2002-February 2003. Fragments of gonads from a total of 226 females and 226 males were obtained and processed following standard histological techniques; then 5-7μm thickness sections were taken and stained in hematoxylin-eosin. Besides, for each specimen, the biometric measurements included the standard length (SL and body weight (BW; and the sex ratio was obtained. The reproductive cycle stages were confirmed by the distribution of oocytes and spermatogenic cells. The type of spawning was determined by the frequency distribution of the reproductive cycle stages and ovarian histology. Based on the microscopic characteristics of the gonads, the following stages of the reproductive cycle were determined: one=Rest, two=Mature, three=Spawned for females or Spent for males; males and females in reproduction were found throughout the study period. Post-spawned ovaries containing oocytes in stages one (initial perinucleolar, two (advanced perinucleolar, three (pre-vitellogenic, four (vitellogenic and post-ovulatory follicles indicated fractionated-type spawning in this species. The smallest breeding male and female measured were 4.6 and 4.9cm standard length, respectively, suggesting stunting. The sex ratio did not vary between males and females along the year and bimonthly, being 1:1. Moreover, L. gibbosus appears to be at stage

  8. Reproduction of the non-native fish Lepomis gibbosus (Perciformes: Centrarchidae) in Brazil.

    Science.gov (United States)

    Santos, Rangel E; Silva, Tayara P; Chehayeb, Igor V; de Magalhães, André L B

    2012-09-01

    Minas Gerais is the fourth largest Brazilian state, and has an estimate of 354 native fish species. However, these fish species may be threatened, as this state has the highest rank of fish introductions reported for Brazil and South America. As one from the total of 85 non-native species detected, Lepomis gibbosus was introduced in the 60s to serve both as foragefish and to improve sport fishing. In this study, we evaluated the establishment of L. gibbosus in a shallow lake in the city ofOuro Preto, Doce River basin, state of Minas Gerais, Southeastern Brazil. We collected fish with fishing rods every two months from March 2002-February 2003. Fragments of gonads from a total of 226 females and 226 males were obtained and processed following standard histological techniques; then 5-7 microm thickness sections were taken and stained in hematoxylin-eosin. Besides, for each specimen, the biometric measurements included the standard length (SL) and body weight (BW); and the sex ratio was obtained. The reproductive cycle stages were confirmed by the distribution of oocytes and spermatogenic cells. The type of spawning was determined by the frequency distribution of the reproductive cycle stages and ovarian histology. Based on the microscopic characteristics of the gonads, the following stages of the reproductive cycle were determined: one=Rest, two=Mature, three=Spawned for females or Spent for males; males and females in reproduction were found throughout the study period. Post-spawned ovaries containing oocytes in stages one (initial perinucleolar), two (advanced perinucleolar), three (pre-vitellogenic), four (vitellogenic) and post-ovulatory follicles indicated fractionated-type spawning in this species. The smallest breeding male and female measured were 4.6 and 4.9cm standard length, respectively, suggesting stunting. The sex ratio did not vary between males and females along the year and bimonthly, being 1:1. Moreover, L. gibbosus appears to be at stage three of

  9. Seasonal and multiannual roost use by Rafinesque's Big-eared Bats in the Coastal Plain of South Carolina.

    Energy Technology Data Exchange (ETDEWEB)

    Loeb, Susan, C.; Zarnoch, Stanley, J.

    2011-12-01

    Little is known about factors affecting year-round use of roosts by Rafinesque's big-eared bats (Corynorhinus rafinesquii) or the long-term fidelity of this species to anthropogenic or natural roosts. The objectives of this study were to test whether seasonal use of roosts by Rafinesque's big-eared bats varied with roost type and environmental conditions within and among seasons and to document multiannual use of natural and anthropogenic structures by this species. We inspected 4 bridges, 1 building, and 59 tree roosts possessing basal cavity openings; roosts were inspected at least once per week from May through October in every year from 2005 through 2008 and once a month from November through April in every year from 2005 through 2009. We found that use of anthropogenic roosts was significantly greater than the use of tree roosts in summer but that the use of structure types did not differ in other seasons. There was significant seasonal variation in use of anthropogenic and tree roosts. Anthropogenic roost use was higher in summer than in all other seasons. There was no significant difference in tree use among spring, summer, and fall, but use in winter was significantly lower in 2 years of the study. Overall use of anthropogenic and tree roosts was positively related to minimum temperature, but the relationship between use of roosts and minimum temperature varied among seasons. Bats showed multiannual fidelity ({ge} 4 years) to all anthropogenic roosts and to some tree roosts, but fidelity of bats to anthropogenic roosts was greater and more consistent than to tree roosts. Our data indicate that Rafinesque's big-eared bats responded differently to environmental conditions among seasons; thus, a variety of structure types and characteristics are necessary for conservation of these bats. We suggest long-term protection of roost structures of all types is necessary for conservation of Rafinesque's big-eared bats in the southeast Coastal Plain.

  10. Availability of caecal habitat as a density-dependent limit on survivorship of Leptorhynchoides thecatus in green sunfish, Lepomis cyanellus.

    Science.gov (United States)

    Ewald, J A; Nickol, B B

    1989-06-01

    Distribution of Leptorhynchoides thecatus (Acanthocephala: Rhadinorhynchidae) among the pyloric caeca and the relationship between site and rate of maturation were studied in laboratory infections of 10, 25 and 40 cystacanths fed to green sunfish, Lepomis cyanellus. After 1 week fish fed at each intensity had significantly different numbers of worms. By the 3rd week post-infection, parasites disappeared from the anterior portion of the intestine. At this time the mean numbers of worms recovered from 25 and 40-cystacanth infections were not significantly different. At the end of the 1st week, the area where caeca join the alimentary tract (between caecal area) and caeca numbered 6 and 7 contained significantly more worms than the other sites. By the 3rd week post-infection only caecum 7 contained significantly more worms, and at 5 weeks there was no significant difference between the number of worms present in any caecum or the between caecal area. Initially worms in the more intense infections matured more slowly, but by the 3rd week post-infection there was no significant difference in the states of maturity. The rate of maturation was not related to the site occupied.

  11. Reproductive characteristics of a population of the washboard mussel Megalonaias nervosa (Rafinesque 1820) in the upper Mississippi River

    Science.gov (United States)

    Woody, C.A.; Holland-Bartels, L.

    1993-01-01

    The authors examined monthly and age-specific gametogenic development of the washboard mussel, Megalonaias nervosa, from April 1986 to March 1987 in navigation Pool 10 of the upper Mississippi River. The authors found M. nervosa to be a late tachytictic breeder. Female marsupia contained eggs or glochidia primarily from August (17 degree C) through October (9 degree C). Males were mature from July through October. Most females released their glochidia in October. Only one female was gravid in Nov (3 degree C). Most mussels were sexually mature at 8 years of age and then had an estimated average size of 68 mm (shell height). Only 8% of individuals less than or equal to 4 years of age showed any degree of reproductive development, while > 90% of age 5 and older individuals had recognizable reproductive material present. In host specificity studies, three fish species were verified as hosts for the glochidial stage. Green sunfish (Lepomis cyanellus), black bullhead (Ictalurus melas), and channel catfish (Ictalurus punctatus) produced juveniles after 26-28 days at 17 degree C. White suckers (Catastomus commersoni) and yellow perch (Perca flavescens) retained glochidia from 23 up to 26 days, but no juveniles were produced. Glochidia remained attached to common carp (Cyprinus carpio) and fathead minnows (Pimephales promelas) less than or equal to 3 days. Channel catfish were retested at 12 degree C and produced juveniles after 56 days.

  12. Distribution of the species of Dipturus Rafinesque (Rajidae, Rajinae, Rajini off Brazil and first record of the Caribbean skate D. teevani (Bigelow & Schroeder, in the Western South Atlantic

    Directory of Open Access Journals (Sweden)

    Ulisses Leite Gomes

    2001-03-01

    Full Text Available The Caribbean skate Dipturus teevani (Bigelow & Schroeder, 1951 is recorded for the first time from Brazilian waters. The specimen was collected in the continental slope off Bahia State. With this record, four species of Dipturus Rafinesque, 1810 are known from Brazil: D. chilensis (Guichenot, 1848, D. leptocauda (Kreft & Stehmann, 1975, D. trachyderma (Krefft & Stehmann, 1975 and D. teevani (Bigelow & Schroeder, 1951. They are typical inhabitants of deep waters between the outer shelf edge (195-200m and the slope (more than 500m. Although morphologically conservative, the species of Dipturus can be distinguished from each other by the number of dorsal and nuchal thorns, the number of caudal thorns, dorsal and ventral spinulation and specific total length. An identification key for the species of Dipturus recorded from Brazil is presented.

  13. The trade-off between food and temperature in the habitat choice of bluegill sunfish

    Science.gov (United States)

    Wildhaber, M.L.

    2001-01-01

    A model is presented to describe the trade-off between food and temperature in bluegills Lepomis macrochirus, where temperature was the primary factor used in determining the patch in which to reside.

  14. Estudo anatômico comparativo da região cefálica pré-branquial de Sphyrna lewini (Griffith & Smith) e Rhizoprionodon lalandii (Valenciennes) (Elasmobranchii, Carcharhiniformes) relacionados com a presença do cefalofólio em Sphyrna Rafinesque Anatomical study on the pre branchial region of Sphyrna lewini (Griffith & Smith) and Rhizoprionodon lalandii (Valenciennes) (Elasmobranchii, Carcharhiniformes) related with the cephalofoil in Sphyrna Rafinesque

    OpenAIRE

    Maisa da Cruz Lima; Ulisses Leite Gomes; Wallace de Souza-Lima; Cristina Paragó

    1997-01-01

    A comparative study on the pre-branchial cranial anatomy of the scalloped hammerhead sharks [Sphyrna lewini (Griffith & Smith, 1834)] and the Brazilian sharpnose shark [Rhizoprionodon lalandii (Valenciennes, 1839)] was carried out to check the modification in the musculature, inervation and optic stalk related to the appearance of the cephalofoil in Sphyrna Rafinesque, 1810. A total of seven adults and one juvenile of R. lalandii and eight juveniles of S. lewini were examined. In S. lewini th...

  15. The marine leech Stibarobdella loricata (Harding, 1924 (Hirudinea, Piscicolidae, parasitic on the angel shark Squatina spp. and sandtiger shark Carcharias taurus Rafinesque, 1810 (Chondrichthyes: Squatinidae, Carchariidae in Southern Brazilian waters

    Directory of Open Access Journals (Sweden)

    Soto J. M. R.

    2003-01-01

    Full Text Available The presence of the marine leech, Stibarobdella loricata (Harding, 1924 (Hirudinea, Piscicolidae, is reported on the southern coast of Brazil, based on seven lots with 47 specimens, between 71 and 182 mm in total length, collected on the dorsal region of angel sharks, Squatina argentina (Marini, 1930; S. guggenheim Marini, 1936; S. punctata Marini, 1936 (Chondrichthyes, Squatinidae; and on the head of a sandtiger shark, Carcharias taurus Rafinesque, 1810 (Chondrichthyes, Carchariidae. This is the first record of S. loricata in the western Atlantic and of its parasitic association with S. argentina, S. guggenheim, S. punctata, and C. taurus.

  16. Predicted effects of future climate warming on thermal habitat suitability for Lake Sturgeon (Acipenser fulvescens, Rafinesque, 1817) in rivers in Wisconsin, USA

    Science.gov (United States)

    Lyons, John D.; Stewart, Jana S.

    2015-01-01

    The Lake Sturgeon (Acipenser fulvescens, Rafinesque, 1817) may be threatened by future climate warming. The purpose of this study was to identify river reaches in Wisconsin, USA, where they might be vulnerable to warming water temperatures. In Wisconsin, A. fulvescens is known from 2291 km of large-river habitat that has been fragmented into 48 discrete river-lake networks isolated by impassable dams. Although the exact temperature tolerances are uncertain, water temperatures above 28–30°C are potentially less suitable for this coolwater species. Predictions from 13 downscaled global climate models were input to a lotic water temperature model to estimate amounts of potential thermally less-suitable habitat at present and for 2046–2065. Currently, 341 km (14.9%) of the known habitat are estimated to regularly exceed 28°C for an entire day, but only 6 km (0.3%) to exceed 30°C. In 2046–2065, 685–2164 km (29.9–94.5%) are projected to exceed 28°C and 33–1056 km (1.4–46.1%) to exceed 30°C. Most river-lake networks have cooler segments, large tributaries, or lakes that might provide temporary escape from potentially less suitable temperatures, but 12 short networks in the Lower Fox and Middle Wisconsin rivers totaling 93.6 km are projected to have no potential thermal refugia. One possible adaptation to climate change could be to provide fish passage or translocation so that riverine Lake Sturgeon might have access to more thermally suitable habitats.

  17. Estudo anatômico comparativo da região cefálica pré-branquial de Sphyrna lewini (Griffith & Smith e Rhizoprionodon lalandii (Valenciennes (Elasmobranchii, Carcharhiniformes relacionados com a presença do cefalofólio em Sphyrna Rafinesque Anatomical study on the pre branchial region of Sphyrna lewini (Griffith & Smith and Rhizoprionodon lalandii (Valenciennes (Elasmobranchii, Carcharhiniformes related with the cephalofoil in Sphyrna Rafinesque

    Directory of Open Access Journals (Sweden)

    Maisa da Cruz Lima

    1997-01-01

    Full Text Available A comparative study on the pre-branchial cranial anatomy of the scalloped hammerhead sharks [Sphyrna lewini (Griffith & Smith, 1834] and the Brazilian sharpnose shark [Rhizoprionodon lalandii (Valenciennes, 1839] was carried out to check the modification in the musculature, inervation and optic stalk related to the appearance of the cephalofoil in Sphyrna Rafinesque, 1810. A total of seven adults and one juvenile of R. lalandii and eight juveniles of S. lewini were examined. In S. lewini the levator palaliquadrati and the levator labii superioris were the most modified cephalic muscles, as they became dorsalventrally attached and laterally developed. Among the oculomotor muscles, the recti followed the lateral expansion of the head constituting the rectal stalk associated with the nerves II, III, IV and VI and the optic stalk. It was observed that the oculomolorius branch "a" does not inervate the adductor mandibulae as it was mentioned in a previous paper. The myological structures and the inervation pattern presented diagnostic characters. Despite the shared characters between Carcharhinidae and the Sphyrnidae, the cephalofoil represents an autapomorphy which includes all the hammerhead sharks in the family Sphyrnidae.

  18. Water-quality assessment of the Albemarle-Pamlico drainage basin, North Carolina and Virginia; trace elements in Asiatic clam (Corbicula fluminea) soft tissues and redbreast sunfish (Lepomis auritus) livers, 1992-93

    Science.gov (United States)

    Ruhl, P.M.; Smith, K.E.

    1996-01-01

    The analysis of potential contaminants in biological tissues is an important part of many water-quality assessment programs, including the National Water-Quality Assessment (NAWQA) Program. Tissue analyses often are used to provide information about (1) direct threats to ecosystem integrity, and (2) the occurrence and distribution of potential contaminants in the environment. During 1992-93, trace elements in Asiatic clam (Corbicula fluminea) soft tissues and redbreast sunfish (Lepomis auritus) livers were analyzed to obtain information about the occurrence and distribution of trace element contaminants in the Albemarle-Pamlico Drainage Basin of North Carolina and Virginia. The investigation was conducted as part of the NAWQA Program. All but 3 of the 22 trace elements that were analyzed were detected. Although all 10 of the U.S. Environmental Protection Agency (U.S. EPA) priority pollutants were detected in the tissues sampled, they were present in relatively low concentrations. Concentrations of U.S. EPA priority pollutants in Asiatic clams collected in the Albemarle-Pamlico Drainage Basin are similar to concentrations observed in other NAWQA study units in the southeastern United States. Mercury (a U.S. EPA priority pollutant) was widely detected, being present in 29 of 30 tissue samples, but concentrations did not exceed the FDA action level for mercury of a risk-based screening value for the general public. Mercury concentrations in Asiatic clams were similar to concentrations in other NAWQA study areas in the Southeast.

  19. Water-quality assessment of the Albemarle-Pamlico Drainage Basin, North Carolina and Virginia; organochlorine compounds in Asiatic clam (Corbicula fluminea) soft tissues and whole redbrest sunfish (Lepomis auritus) 1992-93

    Science.gov (United States)

    Smith, K.E.; Ruhl, P.M.

    1996-01-01

    The analysis of potential contaminants in biological tissues is an important part of many water-quality assessment programs, including the National Water-Quality Assessment (NAWQA) Program. Tissue analyses often are used to provide information about (1) direct threats to ecosystem integrity, and (2) the occurrence and distribution of potential contaminants in the environment. During 1992-93, Asiatic clam (Corbicula fluminea) soft tissues and whole redbreast sunfish (Lepomis auritus) samples were collected and analyzed to obtain information about the occurrence and distribution of organochlorine compounds in the Albemarle-Pamlico drainage Basin of North Carolina and Virginia. The investigation was conducted as part of the NAWQA Program. Relatively few organochlorine compounds were detected and of the compounds detected, all were detected in relatively low concentrations. The organochlorine compounds detected were p,p'-DDD, p,p'-DDE, p,p'-DDT, dieldrin, trans-nonachlor, PCB's, and toxaphene. Multiple compounds were detected at 16 of 19 sites sampled. Compared to Asiatic clams, redbreast sunfish appear to be better bioindicators of organochlorine contamination in aquatic systems. Except for one detection of toxaphene, pesticide concentrations are well below the National Academy of Sciences and National Academy of Engineering (NAS/NAE) guidelines for the protection of fish-eating wildlife.

  20. New host record and molecular characterization of Dicauda atherinoidi Hoffman & Walker (Bivalvulida: Myxobolidae): a parasite of the emerald shiner Notropis atherinoides Rafinesque, 1818 and mimic shiner Notropis vollucellus Cope, 1865.

    Science.gov (United States)

    Loch, T P; Rosser, T G; Baumgartner, W A; Boontai, T; Faisal, M; Griffin, M J

    2017-10-01

    Updated morphological and histopathological descriptions for Dicauda atherinoidi (Bivalvulida:Myxobolidae) and an expanded host range are supplemented with the first molecular data and phylogenetic analyses of the genus. Plasmodia were located on the head, ventrum/body and fins of infected emerald shiner Notropis atherinoides Rafinesque, 1818 and mimic shiner Notropis vollucellus Cope, 1865, a new host species. Myxospores were spherical, ranging 9.3-11.4 μm (10.5 ± 0.4) in length, 9.0-11.0 μm (9.7 ± 0.4) in width and 6.6-7.0 μm (6.8 ± 0.2) thick in sutural view, and possessed 2-3 caudal processes (5.3-68.3 μm, 31.1 ± 13.6) connected to the spore body at the sutural groove, all of which are consistent with the genus Dicauda. In the absence of available Dicauda sequence data, the 18S rDNA sequences from Michigan isolates were most similar to Myxobolus spp. Phylogenetic analyses clustered these isolates with myxobolid species from cyprinid fish, suggesting these parasites may represent an underpopulated group of cyprinid-infecting myxozoans. Histopathology revealed thin-walled plasmodial pseudocysts in the dermis and associated connective tissue, where granulomatous inflammation and focal scale atrophy were also present. Further sampling/sequencing of myxobolids from Notropis spp. should expand these underrepresented myxozoans and offer further insight into Myxobolidae host family tropisms. © 2017 John Wiley & Sons Ltd.

  1. Effects of heated effluents on the reproduction of selected species of the Centrarchid family. Progress report, October 26, 1975--October 25, 1976

    International Nuclear Information System (INIS)

    Clugston, J.P.; Provost, E.E.

    1975-01-01

    Progress is reported on the effects of thermal effluents on the development of gametes in the bluegill, Lepomis macrochirus; on uptake of the trace metal contaminants, Cd, Cr, and Pb by fishes; on food habits of the bluegill and the largemouth bass, Microptems salmoides; on the distribution of fishes in cooling reservoirs; and on the behavior of the largemouth bass

  2. Thermal tolerances of fish from a reservoir receiving heated effluent from a nuclear reactor

    International Nuclear Information System (INIS)

    Holland, W.E.; Smith, M.H.; Gibbons, J.W.; Brown, D.H.

    1974-01-01

    The heat tolerances of bluegill (Lepomis macrochirus) subjected to heated effluent from a nuclear reactor was compared with those of bluegill living at normal temperatures. Three of the four study areas were located in the Par Pond reservoir system on the Savannah River Plant near Aiken, South Carolina. Results shown that at least one species of warm-water fish can adjust to elevated aquatic temperatures in a natural environment by becoming more tolerant. (U.S.)

  3. Laboratory Studies of the Effects of Pressure and Dissolved Gas Supersaturation on Turbine-Passed Fish

    International Nuclear Information System (INIS)

    Abernethy, Cary S; Amidan, Brett G

    2001-01-01

    The objective of this study was to examine the relative importance of pressure changes as a source of turbine-passage injury and mortality. Specific tests were designed to quantify the response of fish to rapid pressure changes typical of turbine passage, with and without the complication of the fish being acclimated to gas supersaturated water. We investigated the responses of rainbow trout (Oncorhynchus mykiss), chinook salmon (O. tshawytscha), and bluegill sunfish (Lepomis macrochirus) to these two stresses, both singly and in combination

  4. Molecular mechanisms of aluminium ions neurotoxicity in brain cells of fish from various pelagic areas

    Directory of Open Access Journals (Sweden)

    E. V. Sukharenko

    2017-07-01

    Full Text Available Neurotoxic effects of aluminum chloride in higher than usual environment concentration (10 mg/L were studied in brains of fishes from various pelagic areas, especially in sunfish (Lepomis macrochirus Rafinesque, 1819, roach (Rutilus rutilus Linnaeus, 1758, crucian carp (Carasius carasius Linnaeus, 1758, goby (Neogobius fluviatilis Pallas, 1811. The intensity of oxidative stress and the content of both cytoskeleton protein GFAP and cytosol Ca-binding protein S100β were determined. The differences in oxidative stress data were observed in the liver and brain of fish during 45 days of treatment with aluminum chloride. The data indicated that in the modeling of aluminum intoxication in mature adult fishes the level of oxidative stress was noticeably higher in the brain than in the liver. This index was lower by1.5–2.0 times on average in the liver cells than in the brain. The obtained data evidently demonstrate high sensitivity to aluminum ions in neural tissue cells of fish from various pelagic areas. Chronic intoxication with aluminum ions induced intense astrogliosis in the fish brain. Astrogliosis was determined as result of overexpression of both cytoskeleton and cytosole markers of astrocytes – GFAP and protein S100β (on 75–112% and 67–105% accordingly. Moreover, it was shown that the neurotixic effect of aluminum ions is closely related to metabolism of astroglial intermediate filaments. The results of western blotting showed a considerable increase in the content of the lysis protein products of GFAP with a range of molecular weight from 40–49 kDa. A similar metabolic disturbance was determined for the upregulation protein S100β expression and particularly in the increase in the content of polypeptide fragments of this protein with molecular weight 24–37 kDa. Thus, the obtained results allow one to presume that aluminum ions activate in the fish brain intracellular proteases which have a capacity to destroy the proteins of

  5. Toxicity of peracetic acid to fish: Variation among species and impact of water chemistry

    DEFF Research Database (Denmark)

    Straus, David L.; Meinelt, Thomas; Liu, Dibo

    2017-01-01

    of fingerling fish that are important to aquaculture were exposed to PAA for 24 h in static toxicity bioassays in well water. These fish were: fathead minnow, Pimephales promelas; black-nose crappie, Pomoxis nigromaculatus; bluegill, Lepomis macrochirus; blue tilapia, Oreochromis aureus; channel catfish...... (LC50) values were estimated with the trimmed Spearman–Karber method using nominal PAA concentrations. The mean 24-h LC50 values ranged from 2.8 to 9.3 mg/L PAA. Fathead minnow were very sensitive and blue tilapia were very tolerant to PAA exposure; LC50 values of other species tested were within...

  6. First record of Neoergasilus japonicus (Poecilostomatoida: Ergasilidae), a parasitic copepod new to the Laurentian Great Lakes

    Science.gov (United States)

    Hudson, Patrick L.; Bowen, Charles A.

    2002-01-01

    The parasitic copepod Neoergasilus japonicus, native to eastern Asia, was first collected from 4 species of fish (fathead minnow, Pimephales promelas; largemouth bass, Micropterus salmoides; pumpkinseed sunfish, Lepomis gibbosus; and yellow perch, Perca flavescens) in July 1994 in Saginaw Bay, Lake Huron, Michigan. Further sampling in the bay in 2001 revealed infections on 7 additional species (bluegill, Lepomis macrochirus; carp, Cyprinus carpio; channel catfish, Ictalurus punctatus; goldfish, Carassius auratus; green sunfish, Lepomis cyanellus; rock bass, Ambloplites rupestris; and smallmouth bass, Micropterus dolomieu). An additional 21 species examined in 2001 were devoid of the parasite. A limited collection of fish from Lake Superior (n = 8) and Lake Michigan (n = 46) in 1994 showed no infection. Neoergasilus japonicus is most frequently found attached to the dorsal fin and, in decreasing frequency, on the anal, tail, pelvic, and pectoral fins. Prevalence generally ranged from 15 to 70 and intensity from 1 to 10. The greatest number of copepods on a single host was 44. The copepod Neoergasilus japonicus appears to disperse over long distances rather quickly, spreading across Europe in 20 yr and then moving on to North America over a span of 10 yr. Its main vehicle of transport and introduction into the Great Lakes is probably exotic fish hosts associated with the fish-culture industry.

  7. Effects of zebra mussels on food webs: Interactions with juvenile bluegill and water residence time

    Science.gov (United States)

    Richardson, W.B.; Bartsch, L.A.

    1997-01-01

    We evaluated how water residence time mediated the impact of zebra mussels Dreissena polymorpha and bluegill sunfish Lepomis macrochirus on experimental food webs established in 1100-1 outdoor mesocosms. Water residence time was manipulated as a surrogate for seston resupply - a critical variable affecting growth and survival of suspension-feeding invertebrates. We used a 2 x 2 x 2 factorial experimental design with eight treatment combinations (3 replicates/treatment) including the presence or absence of Dreissena (2000 per m2), juvenile bluegill (40 per mesocosm), and short (1100 1 per d) or long (220 1 per d) water residence time. Measures of seston concentration (chlorophyll a, turbidity and suspended solids) were greater in the short- compared to long water-residence mesocosms, but intermediate in short water-residence mesocosms containing Dreissena. Abundance of rotifers (Keratella and Polyarthra) was reduced in Dreissena mesocosms and elevated in short residence time mesocosms. Cladocera abundance, in general, was unaffected by the presence of Dreissena; densities were higher in short-residence time mesocosms, and reduced in the presence of Lepomis. The growth of juvenile Lepomis were unaffected by Dreissena because of abundant benthic food. The final total mass of Dreissena was significantly greater in short- than long-residence mesocosms. Impacts of Dreissena on planktonic food webs may not only depend on the density of zebra mussels but also on the residence time of the surrounding water and the resupply of seston. ?? 1997 Kluwer Academic Publishers.

  8. Exposure-related effects of Pseudomonas fluorescens, strain CL145A, on coldwater, coolwater, and warmwater fish

    Science.gov (United States)

    Luoma, James A.; Weber, Kerry L.; Denise A. Mayer,

    2015-01-01

    The exposure-related effects of a commercially prepared spray-dried powder (SDP) formulation of Pseudomonas fluorescens, strain CL145A, were evaluated on coldwater, coolwater, and warmwater fish endemic to the Great Lakes and Upper Mississippi River Basins. Nine species of young-of-the-year fish were exposed to SDP for 24 hours by using continuous-flow, serial-dilution exposure systems at temperatures of 12 degrees Celsius (°C; 2 species; Oncorhynchus mykiss [rainbow trout] and Salvelinus fontinalis [brook trout]), 17 °C (3 species; Perca flavescens [yellow perch], Sander vitreus [walleye], and Acipenser fulvescens [lake sturgeon]), or 22 °C (4 species; Micropterus salmoides [largemouth bass], Micropterus dolomieu [smallmouth bass], Lepomis macrochirus [bluegill sunfish], and Ictalurus punctatus [channel catfish]).

  9. Quarterly Progress Report Covering Period October 1 Through December 31, 1978 Biocide By-Products in Aquatic Environments

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, D.R.; Bean, R.M.; Gibson, C.I.

    1979-03-01

    Analysis of water samples from several locations across the U.S. is underway. We have completed analysis using the Purge and Trap and headspace techniques on several locations. In the freshwater phase of the program we have completed fifteen chloroform acute toxicity bioassays with rainbow trout (Salmo gairdneri), bluegill (Lepomis macrochirus), and catfish (Ictalurus punctatus). Results indicate, in all cases, the LC-50 is well above that which could be expected to be discharged due to power plant chlorination. The LC-50's range from about 15 to 50 ppm chloroform depending on the species. Histological analysis is underway on clams from long-term chlorination by-product exposures. If the results of the histological analysis indicate an effect, further histological examination of samples from other concentrations will be conducted.

  10. Distribution characteristics of freshwater fish in Jeju-do, Korea

    Directory of Open Access Journals (Sweden)

    Wan-Ok Lee

    2015-03-01

    Full Text Available In order to examine distribution characteristics of freshwater fish in Jeju-do, freshwater fish were examined at 17 stations including three reservoirs, 13 stations in six streams, and one estuary wetland. A total of 396 fish individuals of seven species in four families were collected at the three reservoir stations and Lepomis macrochirus, an introduced species that disturbs the ecosystem, was the dominant species (71.7%. There were 770 fish individuals of 22 species in 15 families collected from the six streams. The dominant species was Chaenogobius urotaenius (22.6%. A total of 26 fish of four species in three families were found at the Hadori wetland and the dominant species was Tridentiger obscurus. There were five species of fish found for the first time in Jeju-do during this study; Micropterus salmoides, Eleotris sp., Tridentiger brevispinis, Redigobius bikolanus, and Scatophagus argus. In particular, Eleotris sp. of Eleotridae had not so far been recorded in Korea.

  11. Monogenean parasites of Lepomis gibbosus Linnaeus introduced into the River Durance, France

    Czech Academy of Sciences Publication Activity Database

    Havlátová, Lucie; Ondračková, Markéta; Přikrylová, I.

    2015-01-01

    Roč. 52, č. 4 (2015), s. 323-330 ISSN 0440-6605 R&D Projects: GA ČR GBP505/12/G112 Institutional support: RVO:68081766 Keywords : non-native fish * invasive species * parasites * sunfish * Monogenea * host introductions Subject RIV: EG - Zoology Impact factor: 0.602, year: 2015

  12. Revision of the Sapotaceae of the Malaysian area in a wider sense. VI. Xantolis Rafinesque

    NARCIS (Netherlands)

    Royen, van P.

    1957-01-01

    Xantolis Raf., Sylv. Tell., 1838, 36 — Planchonella Pierre, p.p., Not. bot. Sapot., 1890, 34; Dubard, Ann. Mus. col. Mars. 20, 1912, 41; Lam, Ann. Jard. bot. Bzg, sér. 3, 7, 1925, 193; Lam, l.c., sér. 3, 8, 1927, 467 — Sideroxylon L., p.p., Engler, Nat. Pfl. Fam. 4, 1, 1897, 143 and Nachtrag, 1897,

  13. Molecular Cloning and Sequencing of Hemoglobin-Beta Gene of Channel Catfish, Ictalurus Punctatus Rafinesque

    Science.gov (United States)

    : Hemoglobin-y gene of channel catfish , lctalurus punctatus, was cloned and sequenced . Total RNA from head kidneys was isolated, reverse transcribed and amplified . The sequence of the channel catfish hemoglobin-y gene consists of 600 nucleotides . Analysis of the nucleotide sequence reveals one o...

  14. The order Zoantharia Rafinesque, 1815 (Cnidaria, Anthozoa: Hexacorallia): supraspecific classification and nomenclature

    Science.gov (United States)

    Low, Martyn E. Y.; Sinniger, Frederic; Reimer, James Davis

    2016-01-01

    Abstract Many supraspecific zoantharian names have long and complicated histories. The present list is provided to advise researchers on the current state of supraspecific nomenclature of the zoantharians, particularly given the recent attention paid to the taxonomy, phylogeny, and biodiversity of this order. At the same time, several taxonomic issues brought to light by recent research are resolved. Details on the taxonomic and nomenclatural history of most groups are provided, along with appendices of invalid supraspecific names. PMID:28138291

  15. The diet of the ragged-tooth shark Carcharias taurus Rafinesque ...

    African Journals Online (AJOL)

    The ragged-tooth shark Carcharias taurus is a large predator of inshore coastal waters in the Eastern Cape, South Africa. Born at about 1m long and attaining approximately 3m, stomach content analyses have shown that it feeds largely on teleosts and elasmobranchs, although cephalopods are taken to a lesser extent.

  16. Use and selection of bridges as day roosts by Rafinesque's Big Eared Bats.

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, Frances, M.; Loeb, Susan, C.; Bunch, Mary, S.; Bowerman, William, W.

    2008-03-01

    ABSTRACT.—Rafinesque’s big-eared bats (Corynorhinus rafinesquii) use bridges as day roosts in parts of their range, but information on bridge use across their range is lacking. From May to Aug. 2002 we surveyed 1129 bridges (12.5%) within all 46 counties of South Carolina to determine use and selection of bridges as day roosts by big-eared bats and to document their distribution across the state. During summer 2003, we visited 235 bridges in previously occupied areas of the state to evaluate short-term fidelity to bridge roosts. We found colonies and solitary big-eared bats beneath 38 bridges in 2002 and 54 bridges in 2003. Construction type and size of bridges strongly influenced use in both years; bats selected large, concrete girder bridges and avoided flat-bottomed slab bridges. The majority of occupied bridges (94.7%) were in the Upper and Lower Coastal Plains, but a few bridges (5.3%) were located in the Piedmont. Rafinesque’s big-eared bats were absent beneath bridges in the Blue Ridge Mountains. We established new records of occurrence for 10 counties. In the Coastal Plains, big-eared bats exhibited a high degree of short-term fidelity to roosts in highway bridges. For bridges that were occupied at least once, mean frequency of use was 65.9%. Probability of finding bats under a bridge ranged from 0.46 to 0.73 depending on whether the bridge was occupied in the previous year. Thus, bridges should be inspected three to five times in a given year to determine whether they are being used. Regional bridge roost surveys may be a good method for determining the distribution of C. rafinesquii, particularly in the Coastal Plains, and protection of suitable bridges may be a viable conservation strategy where natural roost sites are limited.

  17. Fish abundances in shoreline habitats and submerged aquatic vegetation in a tidal freshwater embayment of the Potomac River.

    Science.gov (United States)

    Kraus, Richard T; Jones, R Christian

    2012-05-01

    Submerged aquatic vegetation (SAV) is considered an important habitat for juvenile and small forage fish species, but many long-term recruitment surveys do not effectively monitor fish communities in SAV. To better understand the impact of recent large increases of SAV on the fish community in tidal freshwater reaches of the Potomac River, we compared traditional seine sampling from shore with drop ring sampling of SAV beds (primarily Hydrilla) in a shallow water (depths, shoreline and SAV habitats in late summer of three different years (2007, 2008, and 2009). For the dominant species (Fundulus diaphanus, Lepomis macrochirus, Etheostoma olmstedi, Morone americana, Lepomis gibbosus, and Fundulus heteroclitus), density was nearly always higher in SAV, but overall, species richness was highest in shoreline habitats sampled with seines. Although historical monitoring of fish in Gunston Cove (and throughout Chesapeake Bay) is based upon seine sampling (and trawl sampling in deeper areas), the high densities of fish and larger areal extent of SAV indicated that complementary sampling of SAV habitats would produce more accurate trends in abundances of common species. Because drop ring samples cover much less area than seines and may miss rare species, a combination of methods that includes seine sampling is needed for biodiversity assessment. The resurgence of SAV in tidal freshwater signifies improving water quality, and methods we evaluated here support improved inferences about population trends and fish community structure as indicators of ecosystem condition.

  18. Urbanization and the Level of Microplastic Ingestion by Fish: A Comparison of Freshwater Sunfish (Centrarchidae) from the Brazos River watershed, and Pinfish (Sparidae), from the Brazos Estuary and Inshore Marine Sites, Texas, USA

    Science.gov (United States)

    Rieper, K. B.; Peters, C. A.; Bratton, S. P.

    2016-02-01

    While previous research has documented ingestion of macro- and microplastics by aquatic fauna in both freshwater and marine ecosystems, relatively little is known of the environmental and ecological factors influencing the entry and diffusion of plastics and artificial polymers into aquatic foodwebs. Microplastics are defined as 50 μm to 5 mm in length. This study utilized stomach content analysis to compare the level of microplastic artificial polymer ingestion for fish collected from the Brazos River watershed, Brazos estuary, and inshore coastal waters of Texas, USA, in areas with varying levels of urbanization. We collected 318 bluegill (Lepomis macrochirus) and 118 longear sunfish (Lepomis megalotis) at 14 freshwater locales, and 11 samples of 298 pinfish (Lagodon rhomboides) at 6 saltwater locales. Sunfish averaged 12.6 cm in length, and pinfish averaged 14.9 cm. Sunfish averaged .807 microplastics per fish, and pinfish averaged 1.09. The maximum percentage for pinfish with microplastics present per sample (frequency) was 77%, compared to 75% for sunfish. Mean frequencies per sample were also similar: 45% for sunfish and 47% for pinfish. The Brazos River collections, however, had a greater percentage with frequencies of microplastics (cc=.742) and the mean number of plastic particles ingested per fish (cc=.697). The majority of the microplastics were thread shaped, with blue and grey the dominant colors. Comparison with presence of natural food items suggests microplastic ingestion is predominantly incidental for these sentinel fish species.

  19. [Phylogeography and phenotypic diversity of the pumpkinseed Sunfish Lepomis gibbosus (Linnaeus, 1758) of the Northern Black Sea Coast].

    Science.gov (United States)

    Slynko, E E; Novitsky, R A; Bangs, M R; Douglas, M R; Douglas, M E; Khrystenko, D S; Kasyanov, A N; Slynko, Yu V

    2015-02-01

    This paper studies the origin and the genetic and morphological diversity of the pumpkinseed sunfish, a North American invader that is actively expanding its range in the Northern Black Sea Coast. Based on an analysis of variability of the nucleotide sequence of the mtDNA cyt b locus, it was found that all populations of the Northern Black Sea Coast (basins of Dnieper, Dniester, and Danube rivers) are represented by one haplotype. Intraspecific variability is absent. Phylogeographic analysis revealed that the most related haplotype is in a population of pumpkinseed sunfish from New Germany Lake in the Potomac Riverbasin (Maryland, United States), which makes it possible to consider it a parent of the investigated populations. Morphological variation oin countable traits was highly homogeneous. Significant differentiation of a sample from the population of the Dnieper Reservoir from the populations of the Danube and Dniester was found for plastic traits of both the body and cranium. Analysis of the trajectories of development showed that the Dnieper is inhabited by a "pelagic" morpho-ecological form of pumpkinseed sunfish, while the Dniester and Danube is inhabited by a "littoral" form. It is suggested that the success of the settlement of this North American species in the Northern Black Sea Coast does not depend on the origin or the level of its genetic diversity but is instead likely to be ensured by the realization of its available discrete morpho-ecological variability.

  20. The hydrodynamic trails of Lepomis gibbosus (Centrarchidae), Colomesus psittacus (Tetraodontidae) and Thysochromis ansorgii (Cichlidae) investigated with scanning particle image velocimetry.

    Science.gov (United States)

    Hanke, Wolf; Bleckmann, Horst

    2004-04-01

    The hydrodynamic trails of fish belonging to the families Centrarchidae, Tetraodontidae and Cichlidae were investigated. Water movements were measured in six horizontal planes, spaced 10-12 mm apart, for up to 5 min after the passage of a fish, using a computer controlled array of modulated laser diodes. We measured continuously and non-continuously swimming fish. Water velocities decayed rapidly in the leading seconds after the passage of a fish, but could still be measured for a period considerably longer than that. In still water (median water velocity fish was sufficient to be sensed by a piscivorous predator at a distance where vision or hearing frequently fail. Acoustic stimuli estimated from a dipole model in a distance that would be covered by the tested fish in 1 min (4-25 m) were 1.5 x 10(-7) to 3.1 x 10(-10) m s(-2), while the hearing threshold of a perch is three orders of magnitude above that. By contrast, the fish wakes after 1 min (except for one Colomesus wake) contained water velocities between 0.95 and 2.05 mm s(-1), which are within the detection range of hydrodynamic sensory systems. The three species differed with respect to water velocities, the spatial extent of the fish-generated water disturbances and the structure of the wake.

  1. Assessment of tolerant sunfish populations (Lepomis sp.) inhabiting selenium-laden coal ash effluents - 1. Hematological and population level assessment

    Energy Technology Data Exchange (ETDEWEB)

    Lohner, T.W.; Reash, R.J.; Willet, V.E.; Rose, L.A. [American Electrical Power Co., Columbus, OH (United States). Environmental Services Dept.

    2001-07-01

    Sunfish were collected from coal ash effluent-receiving streams and Ohio River watershed reference sites to assess the effects of exposure to low-level selenium concentrations. Selenium, copper, and arsenic concentrations were statistically higher in tissue samples from exposed fish than in reference fish. Leukopenia, lymphocytosis, and neutropenia were evident in exposed fish and were indicative of metal exposure and effect. White blood cell counts and percent lymphocyte values were significantly correlated with liver selenium concentrations. Plasma protein levels were significantly lower in exposed fish than in fish from the Ohio River, indicating that exposed fish may have been nutritionally stressed. Condition factors for fish from the ash pond-receiving streams were the same as, or lower than, those of fish from the reference sites. There was no evidence that the growth rate of fish in the receiving streams differed from that of fish in the reference streams. Despite liver selenium concentrations which exceeded reported toxicity thresholds and evidence of significant hematological changes, there were no significant differences in fish condition factors, liver-somatic indices, or length-weight regressions related to selenium.

  2. Alterations in gills of Lepomis gibbosus, after acute exposure to several xenobiotics (pesticide, detergent and pharmaceuticals): morphometric and biochemical evaluation.

    Science.gov (United States)

    Rodrigues, Sara; Correia, Alberto T; Antunes, Sara C; Nunes, Bruno

    2015-04-01

    In recent decades, scientific research about the effects of anthropogenic xenobiotics on non-target organisms has increased. Among the likely effects, some studies reported the evaluation of biochemical and morphological changes in specific tissues or organs of fishes, such as gills, which are key organs for the direct action of pollutants in the aquatic environment. This work intended to assess biochemical [oxidative stress/phase II conjugation isoenzymes glutathione S-transferase (GSTs)] and morphological [secondary lamellar length (SLL), secondary lamellar width (SLW), interlamellar distance (ID), basal epithelial thickness (BET) and proportion of the secondary lamellae available for gas exchange (PAGE)] changes in gills, after acute exposure to the pesticide chlorfenvinphos, the detergent sodium dodecylsulphate (SDS) and to the anticholinesterasic pharmaceuticals (neostigmine and pyridostigmine). Our results point to a significant, eventually hormetic, effect in the activity of GSTs following exposure to chlorfenvinphos that significantly increased the activity of GSTs at concentration of 0.2 mg/L. The activity of GSTs increased significantly after exposure to 100 mg/L of neostigmine. Considering the morphometric analysis of the gills, the data obtained showed that chlorfenvinphos exerted mainly minor architectural alterations in gills, with the exception of the highest tested concentration of chlorfenvinphos that produced also a slight decrease of the PAGE. The overall conclusions point to a null or negligible toxicity of the selected toxicants towards L. gibbosus, which may be reverted if exposure is withdrawn.

  3. Efficacy of Florfenicol for Control of Mortality Caused by Flavobacterium columnare Infection in Channel Catfish, Ictalurus punctatus (Rafinesque)

    Science.gov (United States)

    The efficacy of florfenicol against Flavobacterium columnare infection was studied in channel catfish (Ictalurus puntatus) fingerlings in 80L aquaria. Non-abraded fish were challenged by immersion on Day 0. Thirty 80 liter tanks were randomly assigned in equal number to two treatment groups, eithe...

  4. El bagre de canal (Ictalurus punctatus Rafinesque, 1818: estado actual y problemática en México

    Directory of Open Access Journals (Sweden)

    Ana Laura Lara-Rivera

    2015-07-01

    Full Text Available El bagre de canal (Ictalurus punctatus es uno de los peces endémicos de Norte América con mayor potencial para la acuicultura. A pesar de esto, los datos sobre su distribución actual son escasos y se desconocen muchos aspectos de su dinámica y desempeño productivo. En el presente estudio se reportan los resultados de una búsqueda bibliográfica y análisis de campo que permiten describir la situación actual del bagre de canal con respecto a su distribución geográfica histórica y actual, así como de la problemática que enfrentan los sistemas productivos de esta especie en México. Se identificó la falta de información e indicadores que permitan conocer la extensión de su hábitat natural, movilización o potencial productivo. La calidad y disponibilidad del agua figuran entre las principales problemáticas de la industria; el alimento supone el mayor gasto para los productores y existe gran heterogeneidad de manejo tanto en granjas reproductoras como de engorde, gran parte de la dinámica productiva sigue un modelo de ensayo y error. Se requiere optimizar y homologar los procesos del sistema productivo de bagre de canal, así como caracterizar correctamente las poblaciones domésticas y silvestres para aprovechar al máximo su potencial.

  5. Histological-morphometric structure of the liver of some cyprinids (Cyprinidae Rafinesque, 1810 from the Zaporizhzhia reservoir

    Directory of Open Access Journals (Sweden)

    T. Sharamok

    2017-12-01

    Full Text Available Purpose. To investigate the state of the liver of wild carp (Cyprinus carpio Linnaeus, 1758 and bream (Abramis brama Linnaeus, 1758 from sites of the Zaporizhzhia reservoir with different human pressures based on histological and cytometric parameters Methodology.The study was carried out in two zones of the Zaporizhzhia reservoir with different degrees and types of human impact - the lower part, located in the agrarian zone (conditionally "environmentally clean" site, and in the Samara Bay with high content of heavy metals in water. The objects of the study were age-4 bream and wild carp. The fish livers for histological studies were obtained from freshly caught fish (in the spring-summer period by anatomical dissection. Fragments of organs of 0.3 – 0.5 cm were taken for preservation. For the preparation of histological preparations, the liver tissue was stained with hematoxylin and eosin. The pictures of histological preparations were made with the aid of a digital camera connected to the microscope. Histologic sections were investigated with 40X magnification using a microscope with the Sciencelab T500 5.17 M digital camera. Findings. Human impact on the hydroelectric system causes signs of hepatocyte hypertrophy and a number of histopathologies in cyprinids in the Samara Bay. The cytometric analysis of the liver showed that the area of hepatocytes in the bay was larger in comparison with the the individuals of similar age from the lower part of the reservoir by 20 and 10% for the wild carp and bream, respectively. In this case, a 14% increase in the small diameter of cells was observed the in hepatocytes of carp, and a 10% increase in large diameter and a 19% increase in nucleus area was observed in bream. The results of the histological invesatigation of the morphological structure of the liver of cyprinids inhabiting the Samara Bay have revealed a number of pathological changes. Fatty liver dystrophy was observed in 37% of bream and 12% of wild carp. The bream liver (2% had necrotic areas of parenchyma. In the 50% of bream and 25% of wild carp, the initial necrosis stages occurred, which were manifested as changes in the nucleus and cytoplasm. Frequently, karyopicnosis and cariolysis and destruction of cellular integrity were observed, which may indicate on a chronic damage and a progressive pathological process. There were no pathologies in the fish inhabiting the lower part of the reservoir. Originality. For the first time a cytometric and histological study of the liver of age-4 bream and wild carp from the Zaporizhian reservoir was performed. Practical Value. The obtained results can be used for the detection of histological biomarkers, the most sensitive to the effect of toxic substances. Fish liver is the most appropriate organ for such researches, since changes in its cytometric and histological parameters are a prerequisite for a number of changes in the metabolism as a separate organ and other interconnected systems of fish organism.

  6. The distribution of the crayfishes Orconectes limosus (Rafinesque) and Astacus astacus (L.) (Crustacea, Decapoda) in the Netherlands

    NARCIS (Netherlands)

    Geelen, J.F.M.

    1978-01-01

    INTRODUCTION According to Holthuis (1950a) the family Astacidae is represented in the Netherlands only by one species, Astacus astacus (L., 1758). Apart from a detailed description of the external anatomy, he gave the following data. The average size of the adults amounts to 80 mm, however, the

  7. Altered gene expression in the brain and liver of female fathead minnows Pimephales promelas Rafinesque exposed to fadrozole

    Energy Technology Data Exchange (ETDEWEB)

    Villeneuve, Daniel L. [US EPA, Duluth, MN (United States); Knoebl, Iris [US EPA, Cincinnati, OH (United States); Larkin, Patrick [Sante Fe Community College, Gainesville, FL (United States); EcoArray, Alachua, FL (United States); Miracle, Ann L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Carter, Barbara J. [EcoArray, Alachua, FL (United States); Denslow, Nancy D. [Univ. of Florida, Gainesville, FL (United States); Ankley, Gerald T. [US EPA, Duluth, MN (United States)

    2008-06-01

    The fathead minnow (Pimephales promelas) is a small fish species widely used for ecotoxicology research and regulatory testing in North America. This study used a novel 2000 gene oligonucleotide microarray to evaluate the effects of the aromatase inhibitor, fadrozole, on gene expression in the liver and brain tissue of exposed females. Exposure to 60 μg 1-1 fadrozole/L for 7 d, resulted in the significant (p<0.05; high-moderate agreement among multiple probes spotted on the array) up-regulation of approximately 47 genes in brain and 188 in liver, and the significant down-regulation of 61 genes in brain and 162 in liver. In particular, fadrozole exposure elicited significant up-regulation of five genes in brain involved in the cholesterol synthesis pathway and altered the expression of over a dozen cytoskeleton-related genes. In the liver, there was notable down-regulation of genes coding for vitellogenin precursors, vigillin, and fibroin-like ovulatory proteins which were consistent with an expected reduction in plasma estradiol concentrations as a result of fadrozole exposure and an associated reduction in measured plasma vitellogenin concentrations. These changes coincided with a general down-regulation of genes coding for non-mitochondrial ribosomal proteins and proteins that play a role in translation. With the exception of the fibroin-like ovulatory proteins, real-time PCR results largely corroborated the microarray responses. Overall, results of this study demonstrate the utility of high density oligonucleotide microarrays for unsupervised, discovery-driven, ecotoxicogenomics research with the fathead minnow and helped inform the subsequent development of a 22,000 gene microarray for the species.

  8. Evidence of microplastic ingestion in the shark Galeus melastomus Rafinesque, 1810 in the continental shelf off the western Mediterranean Sea.

    Science.gov (United States)

    Alomar, Carme; Deudero, Salud

    2017-04-01

    Microplastic (microplastic ingestion. Results have shown that 16.80% of the specimens had ingested a mean value of 0.34 ± 0.07 microplastics/individual. Stomach fullness index ranged from 0.86 to 38.89% and regression analyses showed that fuller stomachs contained more microplastics. A higher quantity of filament type microplastics were identified compared to granular or hard plastic type. No significant differences were given between ingestion values of two locations over the continental shelf providing further evidence of the ubiquitous distribution of microplastics. The findings in this study reflect the availability of this man made contaminant to marine species in seafloor habitats. Based on results from this study, data on microplastic ingestion could be used to study trends in the amount and composition of litter ingested by marine animals in accordance with descriptor 10 of the Marine Strategy Framework Directive. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. A preliminary report on the growth of the rock bass, Ambloplites rupestris (Rafinesque), in two lakes of northern Wisconsin

    Science.gov (United States)

    Wright, Stillman

    1929-01-01

    For several years the Wisconsin Geological and Natural History Survey has been making a limnological study of lakes in the northern part of the State. Because of the fact that so much has been learned of the physical, chemical and biological conditions in these lakes, the region seems particularly favorable for a study of the growth rates of fishes in relation to environmental factors.

  10. Channel Catfish, Ictalurus punctatus Rafinesque 1818, Tetraspanin Membrane Protein Family: Characterization and Expression Analysis of CD81 cDNA

    Science.gov (United States)

    CD81, also known as the target of an antiproliferative antibody 1 (TAPA-1), is a member of tetraspanin integral membrane protein family. This protein plays many important roles in immune functions. In this report, we characterized and analyzed expression of the channel catfish CD81 transcript. T...

  11. Morphological and molecular characterisation of Ditrachybothridium macrocephalum Rees, 1959 (Cestoda: Diphyllidea) from Galeus melastomus Rafinesque in the Western Mediterranean

    Czech Academy of Sciences Publication Activity Database

    Dallarés, S.; Pérez-del-Olmo, A.; Carrasson, M.; Kuchta, Roman

    2015-01-01

    Roč. 92, č. 1 (2015), s. 45-55 ISSN 0165-5752 R&D Projects: GA ČR GBP505/12/G112 Institutional support: RVO:60077344 Keywords : order Diphyllidea * sea * phylogenies Subject RIV: EG - Zoology Impact factor: 1.316, year: 2015

  12. First record of larvae of Arnoglossus imperialis (Rafinesque, 1810) (Bothidae, Pieces) Atlantic species from the Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Devi, C.B.L.; Stephen, R.

    Larvae ranging from 7.7 mm NL to 12.2 mm SL were found in zooplankton from the Agulhas Bank. The long leaf-like larval body, the presence of spiny discoid scutes distributed along the bases of median fin rays, cleithra urohyal, posterior...

  13. Chemical defense of the eastern newt (Notophthalmus viridescens: variation in efficiency against different consumers and in different habitats.

    Directory of Open Access Journals (Sweden)

    Zachary H Marion

    Full Text Available Amphibian secondary metabolites are well known chemically, but their ecological functions are poorly understood--even for well-studied species. For example, the eastern newt (Notophthalmus viridescens is a well known secretor of tetrodotoxin (TTX, with this compound hypothesized to facilitate this salamander's coexistence with a variety of aquatic consumers across the eastern United States. However, this assumption of chemical defense is primarily based on observational data with low replication against only a few predator types. Therefore, we tested the hypothesis that N. viridescens is chemically defended against co-occurring fishes, invertebrates, and amphibian generalist predators and that this defense confers high survivorship when newts are transplanted into both fish-containing and fishless habitats. We found that adult eastern newts were unpalatable to predatory fishes (Micropterus salmoides, Lepomis macrochirus and a crayfish (Procambarus clarkii, but were readily consumed by bullfrogs (Lithobates catesbeianus. The eggs and neonate larvae were also unpalatable to fish (L. macrochirus. Bioassay-guided fractionation confirmed that deterrence is chemical and that ecologically relevant concentrations of TTX would deter feeding. Despite predatory fishes rejecting eastern newts in laboratory assays, field experiments demonstrated that tethered newts suffered high rates of predation in fish-containing ponds. We suggest that this may be due to predation by amphibians (frogs and reptiles (turtles that co-occur with fishes rather than from fishes directly. Fishes suppress invertebrate consumers that prey on bullfrog larvae, leading to higher bullfrog densities in fish containing ponds and thus considerable consumption of newts due to bullfrog tolerance of newt chemical defenses. Amphibian chemical defenses, and consumer responses to them, may be more complex and indirect than previously appreciated.

  14. Urbanization is a major influence on microplastic ingestion by sunfish in the Brazos River Basin, Central Texas, USA

    International Nuclear Information System (INIS)

    Peters, Colleen A.; Bratton, Susan P.

    2016-01-01

    Microplastics, degraded and weathered polymer-based particles, and manufactured products ranging between 50 and 5000 μm in size, are found within marine, freshwater, and estuarine environments. While numerous peer-reviewed papers have quantified the ingestion of microplastics by marine vertebrates, relatively few studies have focused on microplastic ingestion by freshwater organisms. This study documents microplastic and manufactured fiber ingestion by bluegill (Lepomis macrochirus) and longear (Lepomis megalotis) sunfish (Centrarchidae) from the Brazos River Basin, between Lake Whitney and Marlin, Texas, USA. Fourteen sample sites were studied and categorized into urban, downstream, and upstream areas. A total of 436 sunfish were collected, and 196 (45%) stomachs contained microplastics. Four percent (4%) of items sampled were debris on the macro size scale (i.e. >5 mm) and consisted of masses of plastic, metal, Styrofoam, or fishing material, while 96% of items sampled were in the form of microplastic threads. Fish length was statistically correlated to the number of microplastics detected (p = 0.019). Fish collected from urban sites displayed the highest mean number of microplastics ingested, followed by downstream and upstream sites. Microplastics were associated with the ingestion of other debris items (e.g. sand and wood) and correlated to the ingestion of fish eggs, earthworms, and mollusks, suggesting that sunfish incidentally ingest microplastics during their normal feeding methods. The high frequency of microplastic ingestion suggest that further research is needed to determine the residence time of microplastics within the stomach and gut, potential for food web transfer, and adverse effects on wildlife and ecosystemic health. - Highlights: • Sunfish ingest microplastics and manufactured materials at significant levels. • Local urbanization influences microplastic ingestion. • Sunfish incidentally ingest microplastics during their normal

  15. Urbanization is a major influence on microplastic ingestion by sunfish in the Brazos River Basin, Central Texas, USA.

    Science.gov (United States)

    Peters, Colleen A; Bratton, Susan P

    2016-03-01

    Microplastics, degraded and weathered polymer-based particles, and manufactured products ranging between 50 and 5000 μm in size, are found within marine, freshwater, and estuarine environments. While numerous peer-reviewed papers have quantified the ingestion of microplastics by marine vertebrates, relatively few studies have focused on microplastic ingestion by freshwater organisms. This study documents microplastic and manufactured fiber ingestion by bluegill (Lepomis macrochirus) and longear (Lepomis megalotis) sunfish (Centrarchidae) from the Brazos River Basin, between Lake Whitney and Marlin, Texas, USA. Fourteen sample sites were studied and categorized into urban, downstream, and upstream areas. A total of 436 sunfish were collected, and 196 (45%) stomachs contained microplastics. Four percent (4%) of items sampled were debris on the macro size scale (i.e. >5 mm) and consisted of masses of plastic, metal, Styrofoam, or fishing material, while 96% of items sampled were in the form of microplastic threads. Fish length was statistically correlated to the number of microplastics detected (p = 0.019). Fish collected from urban sites displayed the highest mean number of microplastics ingested, followed by downstream and upstream sites. Microplastics were associated with the ingestion of other debris items (e.g. sand and wood) and correlated to the ingestion of fish eggs, earthworms, and mollusks, suggesting that sunfish incidentally ingest microplastics during their normal feeding methods. The high frequency of microplastic ingestion suggest that further research is needed to determine the residence time of microplastics within the stomach and gut, potential for food web transfer, and adverse effects on wildlife and ecosystemic health. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Ionoregulatory Aspects of the Osmorespiratory Compromise during Acute Environmental Hypoxia in 12 Tropical and Temperate Teleosts.

    Science.gov (United States)

    Robertson, Lisa M; Val, Adalberto Luis; Almeida-Val, Vera F; Wood, Chris M

    2015-01-01

    In the traditional osmorespiratory compromise, as seen in the hypoxia-intolerant freshwater rainbow trout (Oncorhynchus mykiss), the branchial modifications that occur to improve O2 uptake during hypoxia result in unfavorable increases in the fluxes of ions and water. However, at least one hypoxia-tolerant freshwater species, the Amazonian oscar (Astronotus ocellatus), shows exactly the opposite: decreased branchial flux rates of ions, water, and nitrogenous wastes during acute hypoxia. In order to find out whether the two strategies were widespread, we used a standard 2-h normoxia, 2-h hypoxia (20%-30% saturation), 2-h normoxic recovery protocol to survey 10 other phylogenetically diverse tropical and temperate species. Unidirectional influx and efflux rates of Na(+) and net flux rates of K(+), ammonia, and urea-N were measured. The flux reduction strategy was seen only in one additional species, the Amazonian tambaqui (Colossoma macropomum), which is similarly hypoxia tolerant and lives in the same ion-poor waters as the oscar. However, five other species exhibited evidence of the increased flux rates typical of the traditional osmorespiratory compromise in the trout: the rosaceu tetra (Hyphessobrycon bentosi rosaceus), the moenkhausia tetra (Moenkhausia diktyota), the bluegill sunfish (Lepomis macrochirus), the zebra fish (Danio rerio), and the goldfish (Carassius auratus). Four other species exhibited no marked flux changes during hypoxia: the cardinal tetra (Paracheirodon axelrodi), the hemigrammus tetra (Hemigrammus rhodostomus), the pumpkinseed sunfish (Lepomis gibbosus), and the Atlantic killifish (Fundulus heteroclitus). Overall, a diversity of strategies exist; we speculate that these may be linked to differences in habitat and/or lifestyle.

  17. Behavioral responses of anuran larvae to chemical cues of native and introduced predators in the Pacific Northwestern United States

    Science.gov (United States)

    Pearl, Christopher A.; Adams, Michael J.; Schuytema, Gerald S.; Nebeker, A.V.

    2003-01-01

    We compared behavioral responses of larvae of three Pacific Northwest anurans from different hydroperiods to water borne cues of native and introduced predators. Two native anurans (Pacific Treefrog, Pseudacris regilla, and Northern Red-Legged Frog, Rana aurora aurora) and introduced Bullfrogs (Rana catesbeiana) responded to water conditioned by native Redside Shiners (Richardsonius balteatus) by increasing refuge use. The larvae of the two native anurans differed in their response to introduced predator cues. Rana aurora aurora, which occur in temporary and permanent waters, responded to both introduced Bluegill Sunfish (Lepomis macrochirus) and introduced Crayfish (Procambarus clarkii). Pseudacris regilla, which occur primarily in temporary ponds, did not respond to water borne cues from either introduced predator. The broader responses of R. a. aurora may indicate greater behavioral plasticity or more exposure to novel predators than experienced by P. regilla. Larvae of introduced R. catesbeiana responded strongly to cues from two fish native to the Pacific northwest but did not alter behavior in response to any of five potential predators with which they coexist in their native range. Fish that occur with R. catesbeiana in their native range generally find Bullfrog larvae unpalatable. This pattern suggests that Bullfrog larvae can recognize cues of novel predators that may find them palatable, which could contribute to their success as an invasive species in the region.

  18. Identifying non-point sources of endocrine active compounds and their biological impacts in freshwater lakes

    Science.gov (United States)

    Baker, Beth H.; Martinovic-Weigelt, Dalma; Ferrey, Mark L.; Barber, Larry B.; Writer, Jeffrey H.; Rosenberry, Donald O.; Kiesling, Richard L.; Lundy, James R.; Schoenfuss, Heiko L.

    2014-01-01

    Contaminants of emerging concern, particularly endocrine active compounds (EACs), have been identified as a threat to aquatic wildlife. However, little is known about the impact of EACs on lakes through groundwater from onsite wastewater treatment systems (OWTS). This study aims to identify specific contributions of OWTS to Sullivan Lake, Minnesota, USA. Lake hydrology, water chemistry, caged bluegill sunfish (Lepomis macrochirus), and larval fathead minnow (Pimephales promelas) exposures were used to assess whether EACs entered the lake through OWTS inflow and the resultant biological impact on fish. Study areas included two OWTS-influenced near-shore sites with native bluegill spawning habitats and two in-lake control sites without nearby EAC sources. Caged bluegill sunfish were analyzed for plasma vitellogenin concentrations, organosomatic indices, and histological pathologies. Surface and porewater was collected from each site and analyzed for EACs. Porewater was also collected for laboratory exposure of larval fathead minnow, before analysis of predator escape performance and gene expression profiles. Chemical analysis showed EACs present at low concentrations at each study site, whereas discrete variations were reported between sites and between summer and fall samplings. Body condition index and liver vacuolization of sunfish were found to differ among study sites as did gene expression in exposed larval fathead minnows. Interestingly, biological exposure data and water chemistry did not match. Therefore, although results highlight the potential impacts of seepage from OWTS, further investigation of mixture effects and life history factor as well as chemical fate is warranted.

  19. Differences between main-channel and off-channel food webs in the upper Mississippi River revealed by fatty acid profiles of consumers

    Science.gov (United States)

    Larson, James H.; Bartsch, Michelle; Gutreuter, Steve; Knights, Brent C.; Bartsch, Lynn; Richardson, William B.; Vallazza, Jonathan M.; Arts, Michael T.

    2015-01-01

    Large river systems are often thought to contain a mosaic of patches with different habitat characteristics driven by differences in flow and mixing environments. Off-channel habitats (e.g., backwater areas, secondary channels) can become semi-isolated from main-channel water inputs, leading to the development of distinct biogeochemical environments. Observations of adult bluegill (Lepomis macrochirus) in the main channel of the Mississippi River led to speculation that the main channel offered superior food resources relative to off-channel areas. One important aspect of food quality is the quantity and composition of polyunsaturated fatty acids (PUFA). We sampled consumers from main-channel and backwater habitats to determine whether they differed in PUFA content. Main-channel individuals for relatively immobile species (young-of-year bluegill, zebra mussels [Dreissena polymorpha], and plain pocketbook mussels [Lampsilis cardium]) had significantly greater PUFA content than off-channel individuals. No difference in PUFA was observed for the more mobile gizzard shad (Dorsoma cepedianum), which may move between main-channel and off-channel habitats even at early life-history stages. As off-channel habitats become isolated from main-channel waters, flow and water column nitrogen decrease, potentially improving conditions for nitrogen-fixing cyanobacteria and vascular plants that, in turn, have low PUFA content. We conclude that main-channel food webs of the upper Mississippi River provide higher quality food resources for some riverine consumers as compared to food webs in off-channel habitats.

  20. Gill lesions and death of bluegill in an acid mine drainage mixing zone

    Science.gov (United States)

    Henry, T.B.; Irwin, E.R.; Grizzle, J.M.; Brumbaugh, W.G.; Wildhaber, M.L.

    2001-01-01

    The toxicity of an acid mine drainage (AMD) mixing zone was investigated by placing bluegill (Lepomis macrochirus) at the confluence of a stream contaminated by AMD and a stream having neutral pH. A mixing channel receiving water from both streams was assembled in the field, during July and October 1996, to determine the toxicity of freshly mixed and aged water (2.9–7.5 min). The AMD stream had elevated concentrations of Al and Fe, which precipitated upon mixing, and of Mn, which did not precipitate in the mixing zone. Fish exposed to freshly mixed water had higher mortality than fish exposed to water after aging. Precipitating Al, but not Fe, accumulated on the gills of bluegill, and accumulation was more rapid early during the mixing process than after aging. Fish exposed for 3.5 h to freshly mixed water had hypertrophy and hyperplasia of gill filament and lamellar epithelial cells. Similar lesions were observed after 6.0 h in fish exposed to water aged after mixing. Results demonstrated that Al was the predominant metal accumulating on the gills of fish in this AMD mixing zone, and that mixing zones can be more toxic than AMD streams in equilibrium.

  1. Aquatic systems in and adjacent to Agulhas National Park with particular reference to the fish fauna

    Directory of Open Access Journals (Sweden)

    I.A. Russell

    2006-12-01

    Full Text Available The study aimed to determine the distribution and relative abundance of freshwater fishes in and adjacent to Agulhas National Park. Fourteen fish species were collected during surveys carried out in the Heuningnes and Ratel river systems and a variety of endorheic pans from 2003 to 2005. Seven of the species are marine fishes tolerant of low salinity (Mugil cephalus, Liza richardsonii, Monodactylus falciformis, Caffrogobius gilchristi, Rhabdosargus holubi, Solea bleekeri, Gilchristella aestuaria with the remaining seven species being primary freshwater fishes. Three are indigenous, including Pseudobarbus burchelli, Sandelia capensis, and Galaxias zebratus of which two morphological forms were recorded within Agulhas National Park. The remaining four species are invasive aliens (Cyprinus carpio, Lepomis macrochirus, Micropterus salmoides, Micropterus punctulatus. Classification using physico-chemical variables indicated four major wetland groups, with fishes occurring predominantly in the group comprising palustrine, lacustrine and riverine wetlands, and in one instance in a brackish endorheic pan. Management actions which should facilitate conservation of indigenous fishes in the Agulhas region are suggested.

  2. Determination of perfluorinated compounds in fish fillet homogenates: Method validation and application to fillet homogenates from the Mississippi River

    Energy Technology Data Exchange (ETDEWEB)

    Malinsky, Michelle Duval, E-mail: mmalinsky@mmm.com [3M Environmental Laboratory, 3M Center, Building 0260-05-N-17, St. Paul, MN 55144-1000 (United States); Jacoby, Cliffton B.; Reagen, William K. [3M Environmental Laboratory, 3M Center, Building 0260-05-N-17, St. Paul, MN 55144-1000 (United States)

    2011-01-10

    We report herein a simple protein precipitation extraction-liquid chromatography tandem mass spectrometry (LC/MS/MS) method, validation, and application for the analysis of perfluorinated carboxylic acids (C7-C12), perfluorinated sulfonic acids (C4, C6, and C8), and perfluorooctane sulfonamide (FOSA) in fish fillet tissue. The method combines a rapid homogenization and protein precipitation tissue extraction procedure using stable-isotope internal standard (IS) calibration. Method validation in bluegill (Lepomis macrochirus) fillet tissue evaluated the following: (1) method accuracy and precision in both extracted matrix-matched calibration and solvent (unextracted) calibration, (2) quantitation of mixed branched and linear isomers of perfluorooctanoate (PFOA) and perfluorooctanesulfonate (PFOS) with linear isomer calibration, (3) quantitation of low level (ppb) perfluorinated compounds (PFCs) in the presence of high level (ppm) PFOS, and (4) specificity from matrix interferences. Both calibration techniques produced method accuracy of at least 100 {+-} 13% with a precision (%RSD) {<=}18% for all target analytes. Method accuracy and precision results for fillet samples from nine different fish species taken from the Mississippi River in 2008 and 2009 are also presented.

  3. Isolation and molecular characterization of a novel picornavirus from baitfish in the USA

    Science.gov (United States)

    Phelps, Nicholas B.D.; Mor, Sunil K.; Armien, Anibal G.; Batts, William N.; Goodwin, Andrew E.; Hopper, Lacey; McCann, Rebekah; Ng, Terry Fei Fan; Puzach, Corey; Waltzek, Thomas B.; Delwart, Eric; Winton, James; Goyal, Sagar M.

    2014-01-01

    During both regulatory and routine surveillance sampling of baitfish from the states of Illinois, Minnesota, Montana, and Wisconsin, USA, isolates (n = 20) of a previously unknown picornavirus were obtained from kidney/spleen or entire viscera of fathead minnows (Pimephales promelas) and brassy minnows (Hybognathus hankinsoni). Following the appearance of a diffuse cytopathic effect, examination of cell culture supernatant by negative contrast electron microscopy revealed the presence of small, round virus particles (∼30–32 nm), with picornavirus-like morphology. Amplification and sequence analysis of viral RNA identified the agent as a novel member of the Picornaviridae family, tentatively named fathead minnow picornavirus (FHMPV). The full FHMPV genome consisted of 7834 nucleotides. Phylogenetic analysis based on 491 amino acid residues of the 3D gene showed 98.6% to 100% identity among the 20 isolates of FHMPV compared in this study while only 49.5% identity with its nearest neighbor, the bluegill picornavirus (BGPV) isolated from bluegill (Lepomis macrochirus). Based on complete polyprotein analysis, the FHMPV shared 58% (P1), 33% (P2) and 43% (P3) amino acid identities with BGPV and shared less than 40% amino acid identity with all other picornaviruses. Hence, we propose the creation of a new genus (Piscevirus) within the Picornaviridae family. The impact of FHMPV on the health of fish populations is unknown at present.

  4. Multiple stressors in amphibian communities: Effects of chemical contamination, bullfrogs, and fish

    Science.gov (United States)

    Boone, M.D.; Semlitsch, R.D.; Little, E.E.; Doyle, M.C.

    2007-01-01

    A leading hypothesis of amphibian population declines is that combinations of multiple stressors contribute to declines. We examined the role that chemical contamination, competition, and predation play singly and in combination in aquatic amphibian communities. We exposed larvae of American toads (Bufo americanus), southern leopard frogs (Rana sphenocephala), and spotted salamanders (Ambystoma maculatum) to overwintered bullfrog tadpoles (R. catesbeiana), bluegill sunfish (Lepomis macrochirus), the insecticide carbaryl, and ammonium nitrate fertilizer in 1000-L mesocosms. Most significantly, our study demonstrated that the presence of multiple factors reduced survival of B. americanus and A. maculatum and lengthened larval periods of R. sphenocephala. The presence of bluegill had the largest impact on the community; it eliminated B. americanus and A. maculatum and reduced the abundance of R. sphenocephala. Chemical contaminants had the second strongest effect on the community with the insecticide, reducing A. maculatum abundance by 50% and increasing the mass of anurans (frogs and toads) at metamorphosis; the fertilizer positively influenced time and mass at metamorphosis for both anurans and A. maculatum. Presence of overwintered bullfrogs reduced mass and increased time to metamorphosis of anurans. While both bluegill and overwintered bullfrog tadpoles had negative effects on the amphibian community, they performed better in the presence of one another and in contaminated habitats. Our results indicate that predicting deleterious combinations from single-factor effects may not be straightforward. Our research supports the hypothesis that combinations of factors can negatively impact some amphibian species and could contribute to population declines. ?? 2007 by the Ecological Society of America.

  5. Potential direct and indirect effects of climate change on a shallow natural lake fish assemblage

    Science.gov (United States)

    Breeggemann, Jason J.; Kaemingk, Mark A.; DeBates, T.J.; Paukert, Craig P.; Krause, J.; Letvin, Alexander P.; Stevens, Tanner M.; Willis, David W.; Chipps, Steven R.

    2015-01-01

    Much uncertainty exists around how fish communities in shallow lakes will respond to climate change. In this study, we modelled the effects of increased water temperatures on consumption and growth rates of two piscivores (northern pike [Esox lucius] and largemouth bass [Micropterus salmoides]) and examined relative effects of consumption by these predators on two prey species (bluegill [Lepomis macrochirus] and yellow perch [Perca flavescens]). Bioenergetics models were used to simulate the effects of climate change on growth and food consumption using predicted 2040 and 2060 temperatures in a shallow Nebraska Sandhill lake, USA. The patterns and magnitude of daily and cumulative consumption during the growing season (April–October) were generally similar between the two predators. However, growth of northern pike was always reduced (−3 to −45% change) compared to largemouth bass that experienced subtle changes (4 to −6% change) in weight by the end of the growing season. Assuming similar population size structure and numbers of predators in 2040–2060, future consumption of bluegill and yellow perch by northern pike and largemouth bass will likely increase (range: 3–24%), necessitating greater prey biomass to meet future energy demands. The timing of increased predator consumption will likely shift towards spring and fall (compared to summer), when prey species may not be available in the quantities required. Our findings suggest that increased water temperatures may affect species at the edge of their native range (i.e. northern pike) and a potential mismatch between predator and prey could exist.

  6. Applying a reservoir functional-zone paradigm to littoral bluegills: differences in length and catch frequency?

    Directory of Open Access Journals (Sweden)

    Nathan Ruhl

    2014-08-01

    Full Text Available Reservoirs exhibit gradients in conditions and resources along the transition from lotic to lentic habitat that may be important to bluegill ecology. The lotic–lentic gradient can be partitioned into three functional zones: the riverine, transitional, and lacustrine zones. We measured catch frequency and length of bluegills (Lepomis macrochirus captured along the periphery of these areas (i.e., in the littoral zone of each functional zone for four small reservoirs in Southeastern Ohio during the summer months of three years. Catch frequency differed between zones for two reservoirs, but these differences were not observed in other years. There was no relationship between reservoir zone and either standard length or catch frequency when the data for all reservoirs were pooled, but we did observe a bimodal length distribution in all reservoirs. A combination of ecological factors including inter and intraspecific competition, predation intensity, management practices, limnology, and assemblage complexity may be mitigating bluegill distribution and abundance in reservoirs. Therefore, a functional zone (categorical approach to understanding bluegill ecology in reservoirs may not be appropriate.

  7. Fish Community Responses to the Establishment of a Piscivore, Northern Pike (Esox lucius), in a Nebraska Sandhill Lake

    Science.gov (United States)

    DeBates, T.J.; Paukert, C.P.; Willis, D.W.

    2003-01-01

    Northern pike (Esox lucius) was first documented in West Long Lake, Nebraska, in 1998 when two pike population estimate on northern pike revealed density and standing stock (i.e., biomass) estimates of 35.8 fish/ha (95% CI= ?? 8.8) and 22.0 kg/ha (95% CI= ?? 5.4), respectively. Consequently, West Long Lake was sampled in 2002 to compare relative abundance, size structure, and growth of bluegill (Lepomis macrochirus), largemouth bass (Micropterus salmoides), and yellow perch (Perca flavescens) prior to and after the establishment of a high-density northern pike population. Bluegill, largemouth bass, and yellow perch relative abundances were significantly lower in 2002 than 1998. Similarly, size structures of all three species were significantly different between years. Size structure declined for both bluegill and yellow perch, and increased for largemouth bass. Growth was significantly higher for bluegill, largemouth bass, and yellow perch in 2002 than 1998. While the fish community changes were expected with the establishment of northern pike, they occurred in a relatively short time period (i.e., four years).

  8. Seasonality of dipteran-mediated methylmercury flux from ponds.

    Science.gov (United States)

    Chumchal, Matthew M; Drenner, Ray W; Hall, MacGregor N; Polk, D Kirkland; Williams, Edward B; Ortega-Rodriguez, Celeste L; Kennedy, James H

    2018-03-12

    Methylmercury (MeHg) is an aquatic contaminant that can be transferred to terrestrial predators by emergent aquatic insects. We assessed the effects of month and pond permanence on dipteran-mediated MeHg flux (calculated as emergent dipteran biomass × dipteran MeHg concentration) in 10 experimental ponds. Emergent dipterans were collected weekly from permanent ponds with bluegill (Lepomis macrochirus; n = 5) and semipermanent ponds without fish (n = 5) over a 7-mo period (February-August, 2015). We detected a significant effect of month on MeHg flux from 6 dipteran taxa and aggregate MeHg flux, with the highest MeHg flux from herbivorous/detritivorous chironomid midges and predatory midges in March; biting midges, phantom midges and herbivorous/detritivorous orthoclad midges in April; and mosquitoes in August. Aggregate dipteran-mediated MeHg flux peaked in April and then declined throughout the remainder of the summer. We did not detect a significant main effect of pond permanence or a significant month × pond permanence interaction effect on MeHg flux for any of the taxa examined in the present study or for aggregate MeHg flux. Given their ubiquity in aquatic systems and their importance in food webs at the land-water interface, dipterans are important taxa that should not be overlooked as a part of the Hg cycle. Environ Toxicol Chem 2018;9999:1-6. © 2018 SETAC. © 2018 SETAC.

  9. Environmental factors regulating the recruitment of walleye Sander vitreus and white bass Morone chrysops in irrigation reservoirs

    Science.gov (United States)

    DeBoer, Jason A.; Pope, Kevin L.; Koupal, Keith D.

    2013-01-01

    Understanding the environmental factors that regulate fish recruitment is essential for effective management of fisheries. Generally, first-year survival, and therefore recruitment, is inherently less consistent in systems with high intra- and interannual variability. Irrigation reservoirs display sporadic patterns of annual drawdown, which can pose a substantial challenge to recruitment of fishes. We developed species-specific models using an 18-year data set compiled from state and federal agencies to investigate variables that regulate the recruitment of walleye Sander vitreus and white bass Morone chrysops in irrigation reservoirs in south-west Nebraska, USA. The candidate model set for walleye included only abiotic variables (water-level elevation, minimum daily air temperature during winter prior to hatching, annual precipitation, spring warming rate and May reservoir discharge), and the candidate model set for white bass included primarily biotic variables (catch per unit effort (CPUE) of black crappie Pomoxis nigromaculatus, CPUE of age-0 walleye, CPUE of bluegill Lepomis macrochirus and CPUE of age-3 and older white bass), each of which had a greater relative importance than the single abiotic variable (minimum daily air temperature during winter after hatching). Our findings improve the understanding of the recruitment of fishes in irrigation reservoirs and the relative roles of abiotic and biotic factors.

  10. Importance of growth rate on Hg and PCB bioaccumulation in fish

    Science.gov (United States)

    Li, Jiajia; Haffner, G. Douglas; Patterson, Gordon; Walters, David M.; Burtnyk, Michael D.; Drouillard, Ken G.

    2018-01-01

    To evaluate the effect of fish growth on mercury (Hg) and polychlorinated biphenyls (PCBs) bioaccumulation, a non‐steady state toxicokinetic model, combined with a Wisconsin bioenergetics model, was developed to simulate Hg and PCB bioaccumulation in Bluegill (Lepomis macrochirus). The model was validated by comparing observed versus predicted Hg and PCB 180 concentrations across 5 age classes from five different waterbodies across North America. The non‐steady state model generated accurate predictions for Hg and PCB bioaccumulation in three of five waterbodies: Apsey, Sharbot and Stonelick Lake. The poor performance of the model for the Detroit River and Lake Hartwell, which were two well‐known contaminated sites with possibly high heterogeneity in spatial contamination, was attributed to changes in the feeding behavior and/ or change in prey contamination. Model simulations indicate that growth dilution is a major component of contaminant bioaccumulation patterns in fish especially during early life stages and was predicted to be more important for hydrophobic PCBs compared to Hg. Simulations which considered tissue specific growth provided some improvement in model performance particularly for PCBs in fish populations which exhibited changes in their whole body lipid content with age. Higher variation in lipid growth compared with that of lean dry protein was also observed between different bluegill populations which partially explains the greater variation in PCB bioaccumulation slopes compared with Hg across sampling sites.

  11. Efficacy of candidate chemicals for preventing attachment of zebra mussels (Dreissena polymorpha)

    Science.gov (United States)

    Cope, W.G.; Bartsch, M.R.; Marking, L.L.

    1997-01-01

    Forty-seven chemicals having potential for preventing the attachment of zebra mussels Dreissena polymorpha were identified and tested. For each chemical, 15 zebra mussels (5-8-mm shell length) in each of two replicates and six treatments were exposed for 48 h followed by a 48-h postexposure period in untreated water. Eleven of the chemicals inhibited the reattachment of zebra mussels after the 48-h exposure; eight had EC50 values ranging from 0.4 to 5.4 mg /L, and three had EC50 values ranging from 19.4 to 29.0 mg/L. Based on an analysis of chemical cost, solubility in water, anticipated treatment concentrations, and potential hazards to humans or the environment, three of the most promising chemicals, all antioxidants (butylated hydroxyanisole [BHA], tert-butylhydroquinone, and tannic acid) were tested on nontarget fish (bluegill, Lepomis macrochirus; channel catfish, Ictalurus punctatus; and rainbow trout, Oncorhynchus mykiss). These chemicals were not selectively toxic to zebra mussels; only the tests with bluegill and BHA and with channel catfish and tannic acid had 48-h LC50 values greater than the concentrations effective for preventing the reattachment of zebra mussels. Although the attachment of zebra mussels can be prevented with selected antioxidants, an alternative formulation should be investigated to minimize effects on nontarget organisms, such as fish.

  12. Fluidized bed ash and passive treatment reduce the adverse effects of acid mine drainage on aquatic organisms.

    Science.gov (United States)

    Porter, Clint M; Nairn, Robert W

    2010-10-15

    Elevated concentrations of acidity and metals in acid mine drainage (AMD) may be effectively addressed by active and passive treatment technologies. However, typical evaluations consider only chemical water quality with little if any regard for biological metrics. Robust evaluations including both chemical and biological indicators of water quality improvement are needed. In this study, injection of alkaline fluidized bed ash (FBA) into a flooded underground coal mine was coupled with a five-cell passive treatment system to ameliorate an abandoned AMD discharge in eastern Oklahoma. The passive system included process units promoting both aerobic and anaerobic treatment mechanisms. Resulting water quality changes and biological responses were evaluated. Organisms of two distinct functional groups (the filter-feeding mollusk Corbicula fluminea and the wide-spectrum feeding fish Lepomis macrochirus) were exposed to mine waters in several treatment cells. The combination of treatment technologies was hypothesized to limit potential negative effects on these aquatic organisms. Tissues were harvested and analyzed for concentrations of several metals (Al, Fe, Mn, Mg, Ca, Ni, Cu and Zn) of interest. Organismal responses, such as hepatosomatic index, condition factor, and condition index, did not vary significantly among organisms exposed within different treatment cells when compared to non-AMD impaired waters. Metal tissue accumulation trends, compared to aqueous concentrations, were observed for Fe, Ni and Zn. Exposure experiments with these two organisms indicated that FBA introductions coupled with passive treatment decreased the potential adverse effects of AMD to biological systems. Copyright © 2010 Elsevier B.V. All rights reserved.

  13. Relationship of weed shiner and young-of-year bluegill and largemouth bass abundance to submersed aquatic vegetation in Navigation Pools 4, 8, and 13 of the Upper Mississippi River, 1998-2012

    Science.gov (United States)

    DeLain, Steven A.; Popp, Walter A.

    2014-01-01

    Aquatic vegetation provides food resources and shelter for many species of fish. This study found a significant relationship between increases in submersed aquatic vegetation (SAV) in four study reaches of the Upper Mississippi River (UMR) and increases in catch-per-unit-effort (CPUE) of weed shiners (Notropis texanus) and age-0 bluegills (Lepomis macrochirus) and largemouth bass (Micropterus salmoides) when all of the study reaches were treated collectively using Long Term Resource Monitoring Program (LTRMP) vegetation and fish data for 1998–2012. The selected fishes were more abundant in study reaches with higher SAV frequencies (Pool 8 and Lower Pool 4) and less abundant in reaches with lower SAV frequencies (Pool 13 and Upper Pool 4). When each study reach was examined independently, the relationship between SAV frequency and CPUE of the three species was not significant in most cases, the primary exception being weed shiners in Lower Pool 4. Results of this study indicate that the prevalence of SAV does affect relative abundance of these vegetation-associated fish species. However, the poor annual relationship between SAV frequency and age-0 relative abundance in individual study reaches indicates that several other factors also govern age-0 abundance. The data indicate that there may be a SAV frequency threshold in backwaters above which there is not a strong relationship with abundance of these fish species. This is indicated by the high annual CPUE variability of the three selected fishes in backwaters of Pool 8 and Lower Pool 4 when SAV exceeded certain frequencies.

  14. Complex inter-Kingdom interactions: carnivorous plants affect growth of an aquatic vertebrate.

    Science.gov (United States)

    Davenport, Jon M; Riley, Alex W

    2017-05-01

    Coexistence of organisms in nature is more likely when phenotypic similarities of individuals are reduced. Despite the lack of similarity, distantly related taxa still compete intensely for shared resources. No larger difference between organisms that share a common prey could exist than between carnivorous plants and animals. However, few studies have considered inter-Kingdom competition among carnivorous plants and animals. In order to evaluate interactions between a carnivorous plant (greater bladderwort, Utricularia vulgaris) and a vertebrate (bluegill, Lepomis macrochirus) on a shared prey (zooplankton), we conducted a mesocosm experiment. We deployed two levels of bladderwort presence (functional and crushed) and measured bluegill responses (survival and growth). Zooplankton abundance was reduced the greatest in bluegill and functional bladderwort treatments. Bluegill survival did not differ among treatments, but growth was greatest with crushed bladderwort. Thus, bluegill growth was facilitated by reducing interference competition in the presence of crushed bladderwort. The facilitating effect was dampened, however, when functional bladderwort removed a shared prey. To our knowledge, this is one of the first studies to experimentally demonstrate interactions between a carnivorous plant and a fish. Our data suggest that carnivorous plants may actively promote or reduce animal co-occurrence from some ecosystems via facilitation or competition. © 2017 The Authors. Journal of Animal Ecology © 2017 British Ecological Society.

  15. Variation in life-history traits between a newly established and long-established population of non-native pumpkinseed, Lepomis gibbosus (Actinopterygii: Perciformes: Centrarchidae)

    Czech Academy of Sciences Publication Activity Database

    Konečná, Markéta; Janáč, Michal; Roche, Kevin Francis; Jurajda, Pavel

    2015-01-01

    Roč. 45, č. 4 (2015), s. 385-392 ISSN 0137-1592 R&D Projects: GA ČR GBP505/12/G112 Institutional support: RVO:68081766 Keywords : freshwater fish * alien species * introduced species * date of introduction * size-at-maturity * fecundity Subject RIV: EH - Ecology, Behaviour Impact factor: 0.622, year: 2015

  16. Contemporary and historical evolutionary processes interact to shape patterns of within-lake phenotypic divergences in polyphenic pumpkinseed sunfish, Lepomis gibbosus.

    Science.gov (United States)

    Weese, Dylan J; Ferguson, Moira M; Robinson, Beren W

    2012-03-01

    Historical and contemporary evolutionary processes can both contribute to patterns of phenotypic variation among populations of a species. Recent studies are revealing how interactions between historical and contemporary processes better explain observed patterns of phenotypic divergence than either process alone. Here, we investigate the roles of evolutionary history and adaptation to current environmental conditions in structuring phenotypic variation among polyphenic populations of sunfish inhabiting 12 postglacial lakes in eastern North America. The pumpkinseed sunfish polyphenism includes sympatric ecomorphs specialized for littoral or pelagic lake habitats. First, we use population genetic methods to test the evolutionary independence of within-lake phenotypic divergences of ecomorphs and to describe patterns of genetic structure among lake populations that clustered into three geographical groupings. We then used multivariate analysis of covariance (MANCOVA) to partition body shape variation (quantified with geometric morphometrics) among the effects of evolutionary history (reflecting phenotypic variation among genetic clusters), the shared phenotypic response of all populations to alternate habitats within lakes (reflecting adaptation to contemporary conditions), and unique phenotypic responses to habitats within lakes nested within genetic clusters. All effects had a significant influence on body form, but the effects of history and the interaction between history and contemporary habitat were larger than contemporary processes in structuring phenotypic variation. This highlights how divergence can be better understood against a known backdrop of evolutionary history.

  17. Morphological correlates of prey consumed by Podarcis melisellensis (Braun, 1877 and P. siculus (Rafinesque, 1810 (Sauria, Lacertidae from two mainland regions in the eastern Adriatic area

    Directory of Open Access Journals (Sweden)

    Stamenković S.Ž.

    2013-01-01

    Full Text Available The correlation between trophic utilization and morphology was studied for two lizard species (Podarcis melisellensis and P. siculus from two mainland localities in the eastern Adriatic area; this is the first report of trophic and morphometric data for P. melisellensis from mainland populations. Variance partitioning showed that most of the variation in morphological traits for the analyzed lizards was the result of differences between species, and to a lesser extent between sexes. Locality did not have a strong effect on the variation of morphological traits. Prey weight is the only characteristic of prey that generally exhibits correlations with morphological characteristics rather than prey size. The pattern of correlations is generally weaker for P. melisellensis than for P. siculus. Optimal foraging theory predictions were generally confirmed: P. siculus is more constrained by trophic resource availability, with a premium on larger and heavier prey consumed in the less productive locality (SM, which can be relaxed in more productive regions (KL. P. melisellensis shows such constraints only for males in the less productive region (SM. Females of both species consume heavier prey. [Projekat Ministarstva nauke Republike Srbije, br. III43001 i br. 173011

  18. Age, Growth and Spatial Distribution of the Life Stages of the Shortfin Mako, Isurus oxyrinchus (Rafinesque, 1810) Caught in the Western and Central Atlantic.

    Science.gov (United States)

    Barreto, Rodrigo R; de Farias, Wialla K T; Andrade, Humber; Santana, Francisco M; Lessa, Rosangela

    2016-01-01

    The shortfin mako (Isurus oxyrinchus) is a highly migratory pelagic shark that preferentially inhabits oceanic regions in practically all oceans. The wide distribution range of this species renders it susceptible to coastal and oceanic fishing operations. The International Union for Conservation of Nature (IUCN) and the International Commission for the Conservation of Atlantic Tunas (ICCAT) consider this species to be highly vulnerable, especially due to its biological parameters, which are different from those of other sharks that occupy the same niche (e.g., Prionace glauca). Consequently, considerable declines in abundance have been detected over various parts of its range, most of which are linked to oceanic longline fishing. The species has conflicting life history parameters in studies conducted in the last 30 years, especially with regard to age and growth. The main discrepancies regard the interpretation of the periodicity of the deposition of band pairs (BPs) on vertebrae and the possibility of ontogenetic variations in growth. Shortfin mako sharks (n = 1325) were sampled by onboard observers of the Brazilian chartered pelagic longline fleet based in northeast Brazil from 2005 to 2011. Lengths were 79 to 250 and 73 to 296 cm (fork length, FL) for males and females, respectively, with a statistically significant difference in size between sexes and differences in the proportion of individuals in each size class. The onboard observers collected a subsample of vertebrae (n = 467), only 234 of which were suitable for analyses. Reliability between readings was satisfactory. However, it was not possible to validate periodicity in the formation of age bands in the sample. Thus, the von Bertalanffy growth function was used to calculate growth rates for the species through the interpretation of BPs in different scenarios: one BP per year (s1), two BPs per year (s2) and two BPs per year until five years of life (s3). Growth parameters varied for both females (Linf = 309.7[s3] to 441.6[s1]; k = 0.04[s1] to 0.13[s3]; t0 = -7.08[s1] and -3.27[s3]) and males (Linf = 291.5[s3] to 340.2[s1]; k = 0.04[s1] to 0.13[s3]; t0 = -7.08[s1] and -3.27[s3]). To advance the understanding of the use of habitat, the first analysis of the spatial distribution of the life stages of the shortfin mako sharks caught by commercial longline fishing operations in the South Atlantic was performed. The findings indicate that the portion of the population exploited by the fleets is predominantly juvenile and future actions should take the following issues into account: improvements in the efficiency of data collection procedures, the reestablishment of the onboard observer program, emergency investments in studies that can contribute to a better understanding of habitat use and life history theory.

  19. Hatch rate of channel catfish Ictalurus punctatus (Rafinesque 1818) eggs treated with 100 mg L-1 copper sulphate pentahydrate. Aquaculture Research

    Science.gov (United States)

    Catfish hatcheries use copper sulfate (CuSO4) as an economical control for saprolegniasis on eggs. This study determines hatch rate of channel catfish eggs in hatching troughs containing 23.8°C flow-through well water when treated with 100 mg/L CuSO4 (ten times the proposed therapeutic dose). Eggs...

  20. Short and long term bystander effect induction by fathead minnows (Pimephales promelas, Rafinesque, 1820) injected with environmentally relevant whole body doses of 226Ra

    International Nuclear Information System (INIS)

    Smith, Richard W.; Seymour, Colin B.; Mothersill, Carmel E.

    2013-01-01

    Bystander effect induction by fathead minnows injected with environmentally relevant doses of 226 Ra was investigated. Twenty four h and 6 months after injection with a single dose of 21, 210 or 2100 μBq, fin tissue samples emitted a pro-apoptotic signal, which reduced the clonogenic survival of an apoptosis sensitive reporter cell line. Twenty four h and 10 weeks after injection explants from non-injected bystander fish, swum with the injected fish, also emitted a pro-apoptotic signal. However 6 months after injection the bystander fish to 21 and 210 μBq injected fish emitted an anti-apoptotic signal. This demonstrates that extremely low dose irradiation can have effects outside of the irradiated fish. This has implications for population and ecosystem responses to contamination. -- Highlights: • Non-injected fish, swum with injected fish, gave the same response for up to 10 weeks. • After 6 months this response by non-injected fish changed to an anti-apoptotic signal. • This shows that 226 Ra contamination can have effects outside of the irradiated fish

  1. Cesium accumulation by aquatic organisms at different trophic levels following an experimental release into a small reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Pinder, J.E., E-mail: jepinder@uga.ed [Savannah River Ecology Laboratory, P. O. Drawer E, Aiken, SC 29802 (United States); Hinton, T.G., E-mail: thomas.hinton@irsn.f [Savannah River Ecology Laboratory, P. O. Drawer E, Aiken, SC 29802 (United States); Taylor, B.E., E-mail: TaylorB@dnr.sc.go [Savannah River Ecology Laboratory, P. O. Drawer E, Aiken, SC 29802 (United States); Whicker, F.W., E-mail: ward.whicker@colostate.ed [Department of Environmental and Radiological Health Sciences, Colorado, State University, Fort Collins, CO 80523-1618 (United States)

    2011-03-15

    The rates of accumulation and subsequent loss of stable cesium ({sup 133}Cs) by organisms at different trophic levels within plankton-based and periphyton-based food chains were measured following the addition of {sup 133}Cs into a small reservoir near Aiken, South Carolina, USA. An uptake parameter u (L kg{sup -1} d{sup -1} dry mass) and a loss rate parameter k (d{sup -1}) were estimated for each organism using time-series measurements of {sup 133}Cs concentrations in water and biota, and these parameters were used to estimate maximum concentrations, times to maximum concentrations, and concentration ratios (C{sub r}). The maximum {sup 133}Cs concentrations for plankton, periphyton, the insect larva Chaoborus punctipennis, which feeds on plankton, and the snail Helisoma trivolvis, which feeds on periphyton, occurred within the first 14 days following the addition, whereas the maximum concentrations for the fish species Lepomis macrochirus and Micropterus salmoides occurred after 170 days. The C{sub r} based on dry mass for plankton and C. punctipennis were 1220 L kg{sup -1} and 5570 L kg{sup -1}, respectively, and were less than the C{sub r} of 8630 L kg{sup -1} for periphyton and 47,700 L kg{sup -1} for H. trivolvis. Although the C{sub r} differed between plankton-based and periphyton-based food chains, they displayed similar levels of biomagnification. Biomagnification was also indicated for fish where the C{sub r} for the mostly nonpiscivorous L. macrochirus of 22,600 L kg{sup -1} was three times less than that for mostly piscivorous M. salmoides of 71,500 L kg{sup -1}. Although the C{sub r} for M. salmoides was greater than those for periphyton and H. trivolvis, the maximum {sup 133}Cs concentrations for periphyton and H. trivolvis were greater than that for M. salmoides. - Research highlights: {yields} A simple uptake and loss model described the Cs dynamics in all the various biota. {yields} Concentrations of Cs were greater in periphyton than in plankton

  2. Factors affecting food chain transfer of mercury in the vicinity of the Nyanza site, Sudbury River, Massachusetts

    Science.gov (United States)

    Haines, T.A.; May, T.W.; Finlayson, R.T.; Mierzykowski, S.E.

    2003-01-01

    The influence of the Nyanza Chemical Waste Dump Superfund Site on the Sudbury River, Massachusetts, was assessed by analysis of sediment, fish prey organisms, and predator fish from four locations in the river system. Whitehall Reservoir is an impoundment upstream of the site, and Reservoir #2 is an impoundment downstream of the site. Cedar Street is a flowing reach upstream of the site, and Sherman Bridge is a flowing reach downstream of the site. Collections of material for analysis were made three times, in May, July, and October. Sediment was analyzed for acid-volatile sulfide (AVS), simultaneously-extracted (SEM) metals (As, Cd, Cr, Hg, Pb, Sb, Zn), and total recoverable Hg. The dominant predatory fish species collected at all sites, largemouth bass (Micropterus salmoides), was analyzed for the same suite of metals as sediment. Analysis of stomach contents of bass identified small fish (yellow perch Perca flavescens, bluegill Lepomis macrochirus, and pumpkinseed Lepomis gibbosus), crayfish, and dragonfly larvae as the dominant prey organisms. Samples of the prey were collected from the same locations and at the same times as predator fish, and were analyzed for total and methyl mercury. Results of AVS and SEM analyses indicated that sediments were not toxic to aquatic invertebrates at any site. The SEM concentrations of As, Cd, and Cr were significantly higher at Reservoir #2 than at the reference sites, and SEM As and Cd were significantly higher at Sherman Bridge than at Cedar St. Sediment total Hg was elevated only at Reservoir #2. Hg was higher at site-influenced locations in all fish species except brown bullhead (Ameiurus nebulosus). Cd was higher in bluegill, black crappie (Pomoxis nigromaculatus), and brown bullhead, and Cr was higher in largemouth bass fillet samples but not in whole-body samples. There were no seasonal differences in sediment or prey organism metals, but some metals in some fish species did vary over time in an inconsistent manner

  3. Locomotion with flexible propulsors: I. Experimental analysis of pectoral fin swimming in sunfish.

    Science.gov (United States)

    Lauder, George V; Madden, Peter G A; Mittal, Rajat; Dong, Haibo; Bozkurttas, Meliha

    2006-12-01

    A full understanding of the mechanics of locomotion can be achieved by incorporating descriptions of (1) three-dimensional kinematics of propulsor movement, (2) material properties of the propulsor, (3) power input and control and (4) the fluid dynamics effects of propulsor motion into (5) a three-dimensional computational framework that models the complexity of propulsors that deform and change area. In addition, robotic models would allow for further experimental investigation of changes to propulsor design and for testing of hypothesized relationships between movement and force production. Such a comprehensive suite of data is not yet available for any flexible propulsor. In this paper, we summarize our research program with the goal of producing a comprehensive data set for each of the five components noted above through a study of pectoral fin locomotion in one species of fish: the bluegill sunfish Lepomis macrochirus. Many fish use pectoral fins exclusively for locomotion, and pectoral fins in most fish are integral to generating force during maneuvering. Pectoral fins are complex structures composed of jointed bony supports that are under active control via pectoral fin musculature. During propulsion in sunfish, the fin deforms considerably, has two leading edges, and sunfish can rotate the whole fin or just control individual sections to vector thrust. Fin material properties vary along the length of fin rays and among rays. Experimental fluid dynamic analysis of sunfish pectoral fin locomotion reveals that the fin generates thrust throughout the fin beat cycle, and that the upper and lower edges each produce distinct simultaneous leading edge vortices. The following companion paper provides data on the computational approach taken to understand locomotion using flexible pectoral fins.

  4. Carbachol-mediated pigment granule dispersion in retinal pigment epithelium requires Ca2+ and calcineurin

    Directory of Open Access Journals (Sweden)

    García Dana M

    2007-12-01

    Full Text Available Abstract Background Inside bluegill (Lepomis macrochirus retinal pigment epithelial cells, pigment granules move in response to extracellular signals. During the process of aggregation, pigment motility is directed toward the cell nucleus; in dispersion, pigment is directed away from the nucleus and into long apical processes. A number of different chemicals have been found to initiate dispersion, and carbachol (an acetylcholine analog is one example. Previous research indicates that the carbachol-receptor interaction activates a Gq-mediated pathway which is commonly linked to Ca2+ mobilization. The purpose of the present study was to test for involvement of calcium and to probe calcium-dependent mediators to reveal their role in carbachol-mediated dispersion. Results Carbachol-induced pigment granule dispersion was blocked by the calcium chelator BAPTA. In contrast, the calcium channel antagonist verapamil, and incubation in Ca2+-free medium failed to block carbachol-induced dispersion. The calcineurin inhibitor cypermethrin blocked carbachol-induced dispersion; whereas, two protein kinase C inhibitors (staurosporine and bisindolylmaleimide II failed to block carbachol-induced dispersion, and the protein kinase C activator phorbol 12-myristate 13-acetate failed to elicit dispersion. Conclusion A rise in intracellular calcium is necessary for carbachol-induced dispersion; however, the Ca2+ requirement is not dependent on extracellular sources, implying that intracellular stores are sufficient to enable pigment granule dispersion to occur. Calcineurin is a likely Ca2+-dependent mediator involved in the signal cascade. Although the pathway leads to the generation of diacylglycerol and calcium (both required for the activation of certain PKC isoforms, our evidence does not support a significant role for PKC.

  5. Undulatory locomotion of flexible foils as biomimetic models for understanding fish propulsion.

    Science.gov (United States)

    Shelton, Ryan M; Thornycroft, Patrick J M; Lauder, George V

    2014-06-15

    An undulatory pattern of body bending in which waves pass along the body from head to tail is a major mechanism of creating thrust in many fish species during steady locomotion. Analyses of live fish swimming have provided the foundation of our current understanding of undulatory locomotion, but our inability to experimentally manipulate key variables such as body length, flexural stiffness and tailbeat frequency in freely swimming fish has limited our ability to investigate a number of important features of undulatory propulsion. In this paper we use a mechanical flapping apparatus to create an undulatory wave in swimming flexible foils driven with a heave motion at their leading edge, and compare this motion with body bending patterns of bluegill sunfish (Lepomis macrochirus) and clown knifefish (Notopterus chitala). We found similar swimming speeds, Reynolds and Strouhal numbers, and patterns of curvature and shape between these fish and foils, suggesting that flexible foils provide a useful model for understanding fish undulatory locomotion. We swam foils with different lengths, stiffnesses and heave frequencies while measuring forces, torques and hydrodynamics. From measured forces and torques we calculated thrust and power coefficients, work and cost of transport for each foil. We found that increasing frequency and stiffness produced faster swimming speeds and more thrust. Increasing length had minimal impact on swimming speed, but had a large impact on Strouhal number, thrust coefficient and cost of transport. Foils that were both stiff and long had the lowest cost of transport (in mJ m(-1) g(-1)) at low cycle frequencies, and the ability to reach the highest speed at high cycle frequencies. © 2014. Published by The Company of Biologists Ltd.

  6. Microscopic examination of skin in native and nonnative fish from Lake Tahoe exposed to ultraviolet radiation and fluoranthene

    Energy Technology Data Exchange (ETDEWEB)

    Gevertz, Amanda K., E-mail: agevertz@geiconsultants.com [Miami University, Department of Zoology, 212 Pearson Hall, Oxford 45056, Ohio (United States); GEI Consultants, Inc. , 4601 DTC Blvd, Suite 900, Denver 80237, Colorado (United States); Oris, James T., E-mail: orisjt@miamioh.edu [Miami University, Department of Zoology, 212 Pearson Hall, Oxford 45056, Ohio (United States)

    2014-02-15

    Highlights: •PAH cause photo-induced toxicity in aquatic organisms in the natural environment. •Montane lakes like Lake Tahoe receive PAH exposure from recreational watercraft. •These lakes are susceptible to invasion and establishment of non-native species. •Non-natives were less tolerant to photo-toxicity compared to native species. •Sensitivity differences were related to levels of oxidative damage in epidermis. -- Abstract: The presence of nonnative species in Lake Tahoe (CA/NV), USA has been an ongoing concern for many decades, and the management of these species calls for an understanding of their ability to cope with the Lake's stressors and for an understanding of their potential to out-compete and reduce the populations of native species. Decreasing levels of ultraviolet radiation (UVR) due to eutrophication and increasing levels of phototoxic polycyclic aromatic hydrocarbons (PAHs) due to recreational activities may combine to affect the relative ability of native versus nonnative fish species to survive in the lake. Following a series of toxicity tests which exposed larvae of the native Lahontan redside minnow (Richardsonius egregius) and the nonnative warm-water bluegill sunfish (Lepomis macrochirus) to UVR and FLU, the occurrence of skin damage and/or physiologic defense mechanisms were studied using multiple microscopic techniques. The native minnow appeared to exhibit fewer instances of skin damage and increased instances of cellular coping mechanisms. This study supports the results of previous work conducted by the authors, who determined that the native redside minnow is the more tolerant of the two species, and that setting and adhering to a water quality standard for UVR transparency may aid in preventing the spread of the less tolerant nonnative bluegill and similar warm-water species.

  7. Gear and seasonal bias associated with abundance and size structure estimates for lentic freshwater fishes

    Science.gov (United States)

    Fischer, Jesse R.; Quist, Michael C.

    2014-01-01

    All freshwater fish sampling methods are biased toward particular species, sizes, and sexes and are further influenced by season, habitat, and fish behavior changes over time. However, little is known about gear-specific biases for many common fish species because few multiple-gear comparison studies exist that have incorporated seasonal dynamics. We sampled six lakes and impoundments representing a diversity of trophic and physical conditions in Iowa, USA, using multiple gear types (i.e., standard modified fyke net, mini-modified fyke net, sinking experimental gill net, bag seine, benthic trawl, boat-mounted electrofisher used diurnally and nocturnally) to determine the influence of sampling methodology and season on fisheries assessments. Specifically, we describe the influence of season on catch per unit effort, proportional size distribution, and the number of samples required to obtain 125 stock-length individuals for 12 species of recreational and ecological importance. Mean catch per unit effort generally peaked in the spring and fall as a result of increased sampling effectiveness in shallow areas and seasonal changes in habitat use (e.g., movement offshore during summer). Mean proportional size distribution decreased from spring to fall for white bass Morone chrysops, largemouth bass Micropterus salmoides, bluegill Lepomis macrochirus, and black crappie Pomoxis nigromaculatus, suggesting selectivity for large and presumably sexually mature individuals in the spring and summer. Overall, the mean number of samples required to sample 125 stock-length individuals was minimized in the fall with sinking experimental gill nets, a boat-mounted electrofisher used at night, and standard modified nets for 11 of the 12 species evaluated. Our results provide fisheries scientists with relative comparisons between several recommended standard sampling methods and illustrate the effects of seasonal variation on estimates of population indices that will be critical to

  8. Hydrologic modification to improve habitat in riverine lakes: Management objectives, experimental approach, and initial conditions

    Science.gov (United States)

    Johnson, Barry L.; Barko, John W.; Gerasimov, Yuri; James, William F.; Litvinov, Alexander; Naimo, Teresa J.; Wiener, James G.; Gaugush, Robert F.; Rogala, James T.; Rogers, Sara J.; Schoettger, R.A.

    1996-01-01

    The Finger Lakes habitat-rehabilitation project is intended to improve physical and chemical conditions for fish in six connected back water lakes in Navigation Pool 5 of the upper Missouri River. The primary management objective is to improve water temperature, dissolved oxygen concentration and current velocity during winter for bluegills, Lepomis macrochirus, and black crappies, Pomoxis nigromaculatus, two of the primary sport fishes in the lakes. The lakes will be hydrologically altered by Installing culverts to Introduce controlled flows of oxygenated water into four lakes, and an existing unregulated culvert on a fifth lake will be equipped with a control gate to regulate inflow. These habitat modifications constitute a manipulative field experiment that will compare pre-project (1991 to summer 1993) and post-project (fall 1993 to 1996) conditions in the lakes, including hydrology, chemistry, rooted vegetation, and fish and macroinvertebrate communities. Initial data indicate that the Finger Lakes differ in water chemistry, hydrology, and macrophyte abundance. Macroinvertebrate communities also differed among lakes: species diversity was highest in lakes with dense aquatic macrophytes. The system seems to support a single fish community, although some species concentrated in individual lakes at different times. The introduction of similar flows into five of the lakes will probably reduce the existing physical and chemical differences among lakes. However, our ability to predict the effects of hydrologic modification on fish populations is limited by uncertainties concerning both the interactions of temperature, oxygen and current in winter and the biological responses of primary and secondary producers. Results from this study should provide guidance for similar habitat-rehabilitation projects in large rivers.

  9. Acute toxicity of an acid mine drainage mixing zone to juvenile bluegill and largemouth bass

    Science.gov (United States)

    Henry, T.B.; Irwin, E.R.; Grizzle, J.M.; Wildhaber, M.L.; Brumbaugh, W.G.

    1999-01-01

    The toxicity of an acid mixing zone produced at the confluence of a stream that was contaminated by acid mine drainage (AMD) and a pH-neutral stream was investigated in toxicity tests with juvenile bluegill Lepomis macrochirus and largemouth bass Micropterus salmoides. Fish mortalities in instream cages located in the mixing zone, below the mixing zone, and upstream in both tributaries were compared to determine relative toxicity at each site. In all tests and for both species, significantly higher mortality was observed in the mixing zone than at any other location, including the acid stream, which had lower pH (2.9-4.3). The mixing zone was defined chemically by rapid precipitation of dissolved aluminum and iron, which arrived from the low-pH stream, and by the presence of white precipitates, which were attached to the substratum and which extended below the confluence. Possible seasonal changes in mixing zone toxicity were investigated by conducting field tests with bluegill in June, July, and August 1996 and in January 1997 and by conducting field tests with largemouth bass in April and May 1997. Toxicity was not significantly different at the extremes of temperature, pH, and metal concentration that occurred in June and July, as compared with January. Toxicity was significantly lower in August; however, elevated stream discharge during the August test may have disturbed mixing zone characteristics. High toxicity in AMD mixing zones may lower the survival of fishes in streams, reduce available habitat, and impede movements of migratory fish.

  10. Seasonality of odonate-mediated methylmercury flux from permanent and semipermanent ponds and potential risk to red-winged blackbirds (Agelaius phoeniceus).

    Science.gov (United States)

    Williams, Edward B; Chumchal, Matthew M; Drenner, Ray W; Kennedy, James H

    2017-10-01

    Methylmercury (MeHg) is an aquatic contaminant that can be transferred to terrestrial predators by emergent aquatic insects such as odonates (damselflies and dragonflies). We assessed the effects of month and pond permanence on odonate-mediated MeHg flux (calculated as emergent odonate biomass × MeHg concentration) in 10 experimental ponds and the potential risk to nestling red-winged blackbirds (Agelaius phoeniceus) posed by consuming MeHg-contaminated odonates. Emergent odonates were collected weekly from permanent ponds with bluegill (Lepomis macrochirus; n = 5) and semipermanent ponds without fish (n = 5) over an 8-mo period (January-August 2015). The MeHg flux from damselflies, aeshnid dragonflies, and libellulid dragonflies began in March and peaked in April, May, and June, respectively, and then declined throughout the rest of the summer. Odonate-mediated MeHg flux from semipermanent ponds without fish was greater than that from permanent ponds with fish. Nesting of red-winged blackbirds overlapped with peak odonate emergence and odonate-mediated MeHg flux. Because their diet can be dominated by damselflies and dragonflies, we tested the hypothesis that MeHg-contaminated odonates may pose a health risk to nestling red-winged blackbirds. Concentrations of MeHg in odonates exceeded wildlife values (the minimum odonate MeHg concentrations causing physiologically significant doses in consumers) for nestlings, suggesting that MeHg-contaminated odonates can pose a health risk to nestling red-winged blackbirds. Environ Toxicol Chem 2017;36:2833-2837. © 2017 SETAC. © 2017 SETAC.

  11. Self-imposed length limits in recreational fisheries

    Science.gov (United States)

    Chizinski, Christopher J.; Martin, Dustin R.; Hurley, Keith L.; Pope, Kevin L.

    2014-01-01

    A primary motivating factor on the decision to harvest a fish among consumptive-orientated anglers is the size of the fish. There is likely a cost-benefit trade-off for harvest of individual fish that is size and species dependent, which should produce a logistic-type response of fish fate (release or harvest) as a function of fish size and species. We define the self-imposed length limit as the length at which a captured fish had a 50% probability of being harvested, which was selected because it marks the length of the fish where the probability of harvest becomes greater than the probability of release. We assessed the influences of fish size, catch per unit effort, size distribution of caught fish, and creel limit on the self-imposed length limits for bluegill Lepomis macrochirus, channel catfish Ictalurus punctatus, black crappie Pomoxis nigromaculatus and white crappie Pomoxis annularis combined, white bass Morone chrysops, and yellow perch Perca flavescens at six lakes in Nebraska, USA. As we predicted, the probability of harvest increased with increasing size for all species harvested, which supported the concept of a size-dependent trade-off in costs and benefits of harvesting individual fish. It was also clear that probability of harvest was not simply defined by fish length, but rather was likely influenced to various degrees by interactions between species, catch rate, size distribution, creel-limit regulation and fish size. A greater understanding of harvest decisions within the context of perceived likelihood that a creel limit will be realized by a given angler party, which is a function of fish availability, harvest regulation and angler skill and orientation, is needed to predict the influence that anglers have on fish communities and to allow managers to sustainable manage exploited fish populations in recreational fisheries.

  12. Comparative Evaluation of Four Presumptive Tests for Blood to Detect Epithelial Injury on Fish

    Energy Technology Data Exchange (ETDEWEB)

    Colotelo, Alison HA; Smokorowski, Karen; Haxton, Tim; Cooke, Steven J.

    2014-06-01

    Current methods of fish epithelial injury detection are limited to gross macroscopic examination that has a subjective bias as well as an inability to reliably quantify the degree of injury. Fluorescein, a presumptive test for blood, has been shown to have the capability to detect and quantify fish epithelial injury. However, there are several other presumptive tests for blood (Bluestar*, phenolphthalein, and HemastixH) that may have benefits over the use of fluorescein, particularly for field research on wild fish. This study investigated the capabilities of these four tests to detect and quantify a variety of injuries commonly encountered by fish (abrasion, cuts, fin frays, and punctures) using the freshwater bluegill Lepomis macrochirus as a model. Fluorescein was consistently found to be the most reliable (i.e., detected the highest proportion of true positive results and rarely detected false positive reactions) of the four presumptive tests for blood compared. Further testing was conducted to examine the reliability of fluorescein. By 24 h after an injury was inflicted, the injury was no longer detectable by fluorescein, and when fluorescein was applied to an injured fish, the fluorescein was no longer detectable 3 h after application. In a comparison of two common anaesthetics used in fisheries research, there was no significant difference in the proportion of injury detected when 3- aminobenzoic acid ethyl ester methanesulfate (tricaine) was used compared with a clove oil and ethanol (1:9) solution. In summary, fluorescein was the most reliable presumptive test for blood examined in this study for the detection and quantification of recent (hours) fish epithelial injury.

  13. Melanomacrophages in three species of free-ranging sharks from the northwestern Atlantic, the blue shark Prionacae glauca (L.), the shortfin mako, Isurus oxyrhinchus Rafinesque, and the thresher, Alopias vulpinus (Bonnaterre).

    Science.gov (United States)

    Borucinska, J D; Kotran, K; Shackett, M; Barker, T

    2009-10-01

    The melanomacrophage aggregates or cells (MMC) are commonly used as biomarkers of exposure to pollution in fish, albeit their numbers and morphological characteristics can be influenced not only by environmental toxins but also by a range of physiological parameters and pathological conditions. Accordingly, before we can use MMC as biomarkers in any fish species, their normal, 'background' characteristics have to be established in apparently healthy fish. The knowledge of MMC in sharks is minimal. The aim of this study was to characterize MMC from 51 free-ranging, large pelagic sharks from the northwestern Atlantic, including shortfin mako, Isurus oxyrhinchus, thresher, Alopias vulpinus and blue shark, Prionacae glauca. The rationale of this study was twofold. First, because, sharks have life histories predisposing them to the accumulation of environmental toxins they constitute good sentinel species of the health of the global marine ecosystem. Second, because many shark populations are in decline or threatened by extinction, we need to expand our understanding of their health status in order to develop appropriate protective measures. All sharks were collected by sports fishing gear between June and August in 2007. Their health condition was assessed by necropsy, morphometrics, and by microscopic examination of gonads, livers, spleens and kidneys. Routine, haematoxylin and eosin and/or Pearl's reagent-stained paraffin embedded sections were studied by light microscopy. Our results provide the first data on the morphometric and morphological characteristics of MMC in viscera of apparently healthy free-ranging sharks from the northwestern Atlantic.

  14. Water-quality models to assess algal community dynamics, water quality, and fish habitat suitability for two agricultural land-use dominated lakes in Minnesota, 2014

    Science.gov (United States)

    Smith, Erik A.; Kiesling, Richard L.; Ziegeweid, Jeffrey R.

    2017-07-20

    proportion of good-growth habitat and a sustained period of optimal growth habitat in the summer, without any periods of lethal oxythermal habitat. For Madison and Pearl Lakes, examples of important cool-water fish, particularly game fish, include northern pike (Esox lucius), walleye (Sander vitreus), and black crappie (Pomoxis nigromaculatus); examples of important warm-water fish include bluegill (Lepomis macrochirus), largemouth bass (Micropterus salmoides), and smallmouth bass (Micropterus dolomieu). Sensitivity analyses were completed to understand lake response effects through the use of controlled departures on certain calibrated model parameters and input nutrient loads. These sensitivity analyses also operated as land-use change scenarios because alterations in agricultural practices, for example, could potentially increase or decrease nutrient loads.

  15. Do laboratory species protect endangered species? Interspecies variation in responses to 17β-estradiol, a model endocrine active compound

    Science.gov (United States)

    Jorgenson, Zachary G.; Buhl, Kevin J.; Bartell, Stephen E.; Schoenfuss, Heiko L.

    2015-01-01

    Although the effects of estrogens on model laboratory species are well documented, their utility as surrogates for other species, including those listed as endangered, are less clear. Traditionally, conservation policies are evaluated based on model organism responses but are intended to protect all species in an environment. We tested the hypothesis that the endangered Rio Grande silvery minnow (Hybognathus amarus) is more vulnerable to endocrine disruption—as assessed through its larval predator-escape performance, survival, juvenile sex ratios, and whole-body vitellogenin concentration—than the commonly used toxicological model species fathead minnow (Pimephales promelas) and the bluegill sunfish (Lepomis macrochirus). Fish were exposed concurrently for 21 days to the model endocrine active compound (EAC) 17ß-estradiol (E2) at 10 ng E2/L and 30 ng E2/L in a flow-through system using reconstituted water that simulated the physicochemical conditions of the Middle Rio Grande in New Mexico, USA. No significant differences were observed between the fathead and silvery minnow in larval predator-escape response or juvenile sex ratio. Rio Grande silvery minnow survival decreased significantly at day 14 compared with the other two species; by day 21, both cyprinid species (silvery minnow and fathead minnow) exhibited a significant decrease in survival compared with bluegill sunfish, a member of the family Centrarchidae. Male Rio Grande silvery minnow showed a significant increase in whole-body vitellogenin concentration in the 10 ng/L treatment, whereas fathead minnow and bluegill sunfish showed no significant increases in vitellogenin concentrations across treatments. Our study showed response differences to estrogen exposures between the two cyprinid species and further divergence in responses between the families Cyprinidae and Centrarchidae. These results suggest that commonly used laboratory model organisms may be less sensitive to EACs than the endangered

  16. Escaping Flatland: three-dimensional kinematics and hydrodynamics of median fins in fishes.

    Science.gov (United States)

    Tytell, Eric D; Standen, Emily M; Lauder, George V

    2008-01-01

    Fish swimming has often been simplified into the motions of a two-dimensional slice through the horizontal midline, as though fishes live in a flat world devoid of a third dimension. While fish bodies do undulate primarily horizontally, this motion has important three-dimensional components, and fish fins can move in a complex three-dimensional manner. Recent results suggest that an understanding of the three-dimensional body shape and fin motions is vital for explaining the mechanics of swimming, and that two-dimensional representations of fish locomotion are misleading. In this study, we first examine axial swimming from the two-dimensional viewpoint, detailing the limitations of this view. Then we present data on the kinematics and hydrodynamics of the dorsal fin, the anal fin and the caudal fin during steady swimming and maneuvering in brook trout, Salvelinus fontinalis, bluegill sunfish, Lepomis macrochirus, and yellow perch, Perca flavescens. These fishes actively move the dorsal and anal fins during swimming, resulting in curvature along both anterio-posterior and dorso-ventral axes. The momentum imparted to the fluid by these fins comprises a substantial portion of total swimming force, adding to thrust and contributing to roll stability. While swimming, the caudal fin also actively curves dorso-ventrally, producing vortices separately from both its upper and lower lobes. This functional separation of the lobes may allow additional control of three-dimensional orientation, but probably reduces swimming efficiency. In contrast, fish may boost the caudal fin's efficiency by taking advantage of the flow from the dorsal and anal fins as it interacts with the flow around the caudal fin itself. During maneuvering, fish readily use their fins outside of the normal planes of motion. For example, the dorsal fin can flick laterally, orienting its surface perpendicular to the body, to help in turning and braking. These data demonstrate that, while fish do move

  17. The release rate of environmental DNA from juvenile and adult fish.

    Directory of Open Access Journals (Sweden)

    Atsushi Maruyama

    Full Text Available The environmental DNA (eDNA technique is expected to become a powerful, non-invasive tool for estimating the distribution and biomass of organisms. This technique was recently shown to be applicable to aquatic vertebrates by collecting extraorganismal DNA floating in the water or absorbed onto suspended particles. However, basic information on eDNA release rate is lacking, despite it being essential for practical applications. In this series of experiments with bluegill sunfish (Lepomis macrochirus, we examined the effect of fish developmental stage on eDNA release rate. eDNA concentration reached equilibrium 3 days after the individual fish were introduced into the separate containers, enabling calculation of the eDNA release rate (copies h-1 from individual fish on the assumption that the number of eDNA released from the fish per unit time equals total degradation in the container (copies h-1. The eDNA release rate was 3-4 times higher in the adult (body weight: 30-75 g than in the juvenile group (0.5-2.0 g. Such positive relationship between fish size and eDNA release rate support the possibility of biomass rather than density estimation using eDNA techniques. However, the eDNA release rate per fish body weight (copies h-1 g-1 was slightly higher in the juvenile than the adult group, which is likely because of the ontogenetic reduction in metabolic activity. Therefore, quantitative eDNA data should be carefully interpreted to avoid overestimating biomass when the population is dominated by juveniles, because the age structure of the focal population is often variable and unseen in the field. eDNA degradation rates (copies l-1 h-1, calculated by curve fitting of time-dependent changes in eDNA concentrations after fish removal, were 5.1-15.9% per hour (half-life: 6.3 h. This suggests that quantitative eDNA data should be corrected using a degradation curve attained in the target field.

  18. Do laboratory species protect endangered species? Interspecies variation in responses to 17β-estradiol, a model endocrine active compound.

    Science.gov (United States)

    Jorgenson, Z G; Buhl, K; Bartell, S E; Schoenfuss, H L

    2015-01-01

    Although the effects of estrogens on model laboratory species are well documented, their utility as surrogates for other species, including those listed as endangered, are less clear. Traditionally, conservation policies are evaluated based on model organism responses but are intended to protect all species in an environment. We tested the hypothesis that the endangered Rio Grande silvery minnow (Hybognathus amarus) is more vulnerable to endocrine disruption-as assessed through its larval predator-escape performance, survival, juvenile sex ratios, and whole-body vitellogenin concentration-than the commonly used toxicological model species fathead minnow (Pimephales promelas) and the bluegill sunfish (Lepomis macrochirus). Fish were exposed concurrently for 21 days to the model endocrine active compound (EAC) 17ß-estradiol (E2) at 10 ng E2/L and 30 ng E2/L in a flow-through system using reconstituted water that simulated the physicochemical conditions of the Middle Rio Grande in New Mexico, USA. No significant differences were observed between the fathead and silvery minnow in larval predator-escape response or juvenile sex ratio. Rio Grande silvery minnow survival decreased significantly at day 14 compared with the other two species; by day 21, both cyprinid species (silvery minnow and fathead minnow) exhibited a significant decrease in survival compared with bluegill sunfish, a member of the family Centrarchidae. Male Rio Grande silvery minnow showed a significant increase in whole-body vitellogenin concentration in the 10 ng/L treatment, whereas fathead minnow and bluegill sunfish showed no significant increases in vitellogenin concentrations across treatments. Our study showed response differences to estrogen exposures between the two cyprinid species and further divergence in responses between the families Cyprinidae and Centrarchidae. These results suggest that commonly used laboratory model organisms may be less sensitive to EACs than the endangered Rio

  19. Mercury bioaccumulation in fish in a region affected by historic gold mining; the South Yuba River, Deer Creek, and Bear River watersheds, California, 1999

    Science.gov (United States)

    May, Jason T.; Hothem, Roger L.; Alpers, Charles N.; Law, Matthew A.

    2000-01-01

    Mercury that was used historically for gold recovery in mining areas of the Sierra Nevada continues to enter local and downstream water bodies, including the Sacramento Delta and the San Francisco Bay of northern California. Methylmercury is of particular concern because it is the most prevalent form of mercury in fish and is a potent neurotoxin that bioaccumulates at successive trophic levels within food webs. In April 1999, the U.S. Geological Survey, in cooperation with several other agencies the Forest Service (U.S. Department of Agriculture), the Bureau of Land Management, the U.S. Environmental Protection Agency, the California State Water Resources Control Board, and the Nevada County Resource Conservation District began a pilot investigation to characterize the occurrence and distribution of mercury in water, sediment, and biota in the South Yuba River, Deer Creek, and Bear River watersheds of California. Biological samples consisted of semi-aquatic and aquatic insects, amphibians, bird eggs, and fish. Fish were collected from 5 reservoirs and 14 stream sites during August through October 1999 to assess the distribution of mercury in these watersheds. Fish that were collected from reservoirs included top trophic level predators (black basses, Micropterus spp.) intermediate trophic level predators [sunfish (blue gill, Lepomis macrochirus; green sunfish, Lepomis cyanellus; and black crappie, Poxomis nigromaculatus)] and benthic omnivores (channel catfish, Ictularus punctatus). At stream sites, the species collected were upper trophic level salmonids (brown trout, Salmo trutta) and upper-to-intermediate trophic level salmonids (rainbow trout, Oncorhynchus mykiss). Boneless and skinless fillet portions from 161 fish were analyzed for total mercury; 131 samples were individual fish, and the remaining 30 fish were combined into 10 composite samples of three fish each of the same species and size class. Mercury concentrations in samples of black basses

  20. Non-target trials with Pseudomonas fluorescens strain CL145A, a lethal control agent of dreissenid mussels (Bivalvia: Dreissenidae

    Directory of Open Access Journals (Sweden)

    Daniel P. Molloy

    2013-01-01

    Full Text Available In an effort to develop an efficacious and environmentally safe method for managing zebra mussels (Dreissena polymorpha and quaggamussels (Dreissena rostriformis bugensis, we initiated a research project investigating the potential use of bacteria and their naturalmetabolic products as biocontrol agents. This project resulted in the discovery of an environmental isolate lethal to dreissenid mussels,Pseudomonas fluorescens strain CL145A (Pf-CL145A. In previous published reports we have demonstrated that: 1 Pf-CL145A’s mode ofaction is intoxication (not infection; 2 natural product within ingested bacterial cells lyse digestive tract epithelial cells leading to dreisseniddeath; and 3 high dreissenid kill rates (>90% are achievable following treatment with Pf-CL145A cells, irrespective of whether thebacterial cells are dead or alive. Investigating the environmental safety of Pf-CL145A was also a key element in our research efforts, andherein, we report the results of non-target trials demonstrating Pf-CL145A’s high specificity to dreissenids. These acute toxicity trials weretypically single-dose, short-term (24-72 h exposures to Pf-CL145A cells under aerated conditions at concentrations highly lethal todreissenids (100 or 200 mg/L. These trials produced no evidence of mortality among the ciliate Colpidium colpoda, the cladoceran Daphniamagna, three fish species (Pimephales promelas, Salmo trutta, and Lepomis macrochirus, and seven bivalve species (Mytilus edulis,Pyganodon grandis, Pyganodon cataracta, Lasmigona compressa, Strophitus undulatus, Lampsilis radiata, and Elliptio complanata. Lowmortality (3-27% was recorded in the amphipod Hyalella azteca, but additional trials suggested that most, if not all, of the mortality couldbe attributed to some other unidentified factor (e.g., possibly particle load or a water quality issue rather than Pf-CL145A’s dreissenidkillingnatural product. In terms of potential environmental safety, the results of

  1. Selenium in ecosystems within the mountaintop coal mining and valley-fill region of southern West Virginia-assessment and ecosystem-scale modeling

    Science.gov (United States)

    Presser, Theresa S.

    2013-01-01

    acted as an integrator of organic-rich, fine-grained biomass present in streams. The base-case food web modeled for streams was suspended particulate material to aquatic insect to creek chub, with comparative modeling of a direct particulate-to-stoneroller food web. Model species for a reservoir setting were based on an earlier study of bluegill sunfish (Lepomis macrochirus), green sunfish (Lepomis cyanellus), and largemouth bass (Micropterus salmoides). Several reservoir food webs were considered based on a variety of invertebrates (insect, snail, clam). For stream and reservoir settings, predicted Se concentrations in exposure scenarios showed a high degree of correlation (r2 = 0.91 for invertebrates and 0.75 for fish) with field observations of Se concentrations when modeling was initiated from suspended-particulate-material Se concentrations and model transfer parameters defined previously in the literature were used. These strong correlations validate the derived site-specific model and establish sufficient confidence that the predictions from the developed model can be quantitatively applied to the ecosystems in southern West Virginia. An application of modeling used a metric describing the partitioning of Se between particulate material and dissolved phases (Kd) to allow determination of a dissolved Se concentration that would be necessary to attain a site-specific Se fish body burden. The operationally defined Kd quantifies the complex process of transformation at the base of a food web on a site-specific basis. The magnitude of this metric is known to vary with such factors as Se speciation, particulate-material type, and hydrology. This application (1) ties dissolved Se concentrations to fish tissue concentrations; (2) allows consideration of different choices for intervening site-specific exposure steps that set Se bioaccumulation, partitioning, and bioavailability; and (3) generates implications for management decisions that define protection through

  2. Rafinesque’s names for western American mammals, including the earliest scientific name for the coyote (Canis latrans Say, 1822), based on the apocryphal journal of Charles Le Raye

    Science.gov (United States)

    Woodman, Neal

    2015-01-01

    In 1817, the naturalist Constantine S. Rafinesque named nine new species of mammals from the American West, indicating the recently published journal of Charles Le Raye as the primary source for his descriptions. Le Raye was purported to be a French Canadian fur trader who, as a captive of the Sioux, had traveled across broad portions of the Missouri and Yellowstone river drainages a few years before the Lewis and Clark Expedition (1804-1806) traversed much of the same region. Le Raye's journal was relied upon by generations of scholars as a valuable source documenting the native peoples and natural history of the Upper Missouri river in the era just prior to European settlement. Subsequent research, however, has shown that Le Raye never existed, and his purported journal is fraudulent. Despite this, Rafinesque's creation of the names followed conventional and accepted practice at the time, and they are porentially available. Fortunately, much of the Le Raye journal was based on verifiable sources, such as Patrick Gass's published account of the Lewis and Clark Expedition. Identification of the original source materials makes it possible to establish the correct application of Rafinesque's names and to determine their current status. This process reveals that the earliest scientific name for the coyote (Canis latrans Say, 1822) was Canis chlorops Rafinesque, 1817; this name is now a nomen oblitum, however, and is no longer available.

  3. Protocols for care and handling of deer and elk at the Starkey Experimental Forest and Range.

    Science.gov (United States)

    Michael J. Wisdom; John G. Cook; Mary M. Rowland; James H. Noyes

    1993-01-01

    Several hundred Rocky Mountain elk (Cervus elaphus nelsoni V. Bailey) and Rocky Mountain mule deer (Odocoileus hemionus hemionus Rafinesque) inhabit a fenced, 25,000-acre enclosure at the Starkey Experimental Forest and Range in the Blue Mountains of northeast Oregon. Research there requires handling...

  4. Techniques to construct New Zealand elk-proof fence.

    Science.gov (United States)

    Larry D. Bryant; Jack W. Thomas; Mary M. Rowland

    1993-01-01

    An elk-proof fence was built in 1987 at the Starkey Experimental Forest and Range in northeast Oregon. The 25,000-acre research enclosure holds several hundred Rocky Mountain elk (Cervus elaphus nelsoni V. Bailey) and Rocky Mountain mule deer (Odocoileus hemionus hemionus Rafinesque) year round. The fence, constructed with high...

  5. Effect of stocking biomass on solids, phytoplankton communities, common off-flavors, and production parameters in a channel catfish biofloc technology production system

    Science.gov (United States)

    The effect of initial channel catfish (Ictalurus punctatus, Rafinesque, 1818) fingerling biomass (1.4, 1.8, or 2.3 kg m-3) on phytoplankton communities, common off-flavors, and stocker catfish production parameters was evaluated in biofloc technology production tanks. Stocker catfish size (145.5 – 1...

  6. Threadfin shad impacts phytoplankton and zooplankton community structures in channel catfish ponds

    Science.gov (United States)

    Plankton community structure and chlorophyll a concentration were compared in 12 0.1-ha earthen ponds co-stocked with channel catfish (Ictalurus punctatus Rafinesque, 1818) in multiple-batch culture (initial biomass = 5,458 kg ha-1) and a planktivore, threadfin shad (Dorosoma petenense Güther, 1867;...

  7. 2147-IJBCS-Article-Abdoulaye Kone

    African Journals Online (AJOL)

    hp

    Carcharhiniformes - Sphyrnidae) in the coastal region of Kerala, India. Int. J. Biosci., 1(6): 14-26. Mollet HF, Cliff G, Pratt HL, Stevens JD. 2000. Reproductive biology of the female shortfin mako, Isurus oxyrinchus. Rafinesque, 1810, with comments on the.

  8. Overview and new records of the species of the tribes Dyschiriini and Clivinini from Iraq (Coleoptera, Carabidae, Scaritinae).

    Science.gov (United States)

    Bulirsch, Petr; Stachowiak, Mieczysław

    2017-01-01

    The genera Clivinopsis Bedel 1895 and Torretassoa Schatzmayr & Koch 1933 have been recorded in Iraq for the first time. New records of several species of Dyschirius Bonelli 1810 Dyschiriodes Jeannel 1941 (Dyschiriini W. Kolbe 1880) and Clivina Latreille 1802 (Clivinini Rafinesque 1815) are given. The identification key to the species of Dyschiriini from Iraq is provided.

  9. Overview and new records of the species of the tribes Dyschiriini and Clivinini from Iraq (Coleoptera, Carabidae, Scaritinae

    Directory of Open Access Journals (Sweden)

    Petr Bulirsch

    2017-05-01

    Full Text Available The genera Clivinopsis Bedel 1895 and Torretassoa Schatzmayr & Koch 1933 have been recorded in Iraq for the first time. New records of several species of Dyschirius Bonelli 1810 Dyschiriodes Jeannel 1941 (Dyschiriini W. Kolbe 1880 and Clivina Latreille 1802 (Clivinini Rafinesque 1815 are given. The identification key to the species of Dyschiriini from Iraq is provided.

  10. Fish vertebra from Miocene beds at Govce, Slovenia

    Directory of Open Access Journals (Sweden)

    Vasja Mikuž

    2014-07-01

    Full Text Available The article discusses a vertebra and a small shark tooth found in the Miocene Govce sandstone near Govce west of Laško in central Slovenia. The vertebra belongs to a shark of the superorder Galeomorphii but we could not determine it with greater precision. The small tooth was assigned to Carcharias cf. taurus Rafinesque, 1810. The nannofossils in the sample are scarce and did not allow dating at biozone precision.

  11. Intra- and interspecific responses to Rafinesque’s big-eared bat (Corynorhinus rafinesquii) social calls

    Science.gov (United States)

    S. Loeb; E. Britzke

    2010-01-01

    Bats respond to the calls of conspecifics as well as to calls of other species; however, few studies have attempted to quantify these responses or understand the functions of these calls. We tested the response of Rafinesque’s big-eared bats (Corynorhinus rafinesquii) to social calls as a possible method to increase capture success and to understand the function of...

  12. Remedial Investigation Addendum Report Data Item A009. Volume 1: Report Test

    Science.gov (United States)

    1993-12-01

    Bullhead * ictalurus nebulosus (Lesueur) Brown Bullhead PERCIFORMES Percichthyidae Morone americana (Gmelin) White Perch Centrarchidae Lepomnis...Bullhead PERCIFORMES Centrarchidae Lepomis gibbosus (Linnaeus) P umpkinseed Pomoxis nigromaculatus (Lesueur) Black Crappie W006931 OT.080/5 z 0’ N ý - efi

  13. European distribution for metacercariae of the North American digenean Posthodiplostomum cf. minimum centrarchi (Strigeiformes: Diplostomidae)

    Czech Academy of Sciences Publication Activity Database

    Kvach, Yuriy; Jurajda, Pavel; Bryjová, Anna; Trichkova, T.; Ribeiro, F.; Přikrylová, I.; Ondračková, Markéta

    2017-01-01

    Roč. 66, č. 5 (2017), s. 635-642 ISSN 1383-5769 R&D Projects: GA ČR(CZ) GBP505/12/G112 Institutional support: RVO:68081766 Keywords : Lepomis gibbosus * Micropterus salmoides * White grub * Physid snails * Non-indigenous species Subject RIV: EG - Zoology OBOR OECD: Parasitology Impact factor: 1.744, year: 2016

  14. SPECIES COMPOSITION OF THE FISH SPECIES IN KEMER RESERVOIR AND AKCAY STREAM, AYDIN, TURKEY

    Directory of Open Access Journals (Sweden)

    Gulnaz ÖZCAN

    2009-06-01

    Full Text Available The study was carried out in Kemer Reservoir and Akcay Stream between December 2004 and June 2006. Fish samples were caught by using gill nets, cast nets and electrofishing. Fifteen species belonging to 6 families were caught during the study. Four species, Acanthobrama mirabilis (47.0, Lepomis gibbosus (18.8, Chondrostoma meandrense (12.8 and Barbus pectoralis (8.6 are dominant fish species in the reservoir.

  15. Sur les poissons fossiles (Teleosteens. Cyprinidae des gypses turoliens du fosse de Teruel: essai d'approche paléoécologique

    Directory of Open Access Journals (Sweden)

    Gaudant, J.

    1984-12-01

    Full Text Available The revision of the Turolian fossil fishes from Los Aljezares, near Teruel (Spain leads one to .establish that they belong to the Recent genus Rutilus RAFINESQUE. So, they must be named R. pochecoi (ROYO GÓMEZ. The occurrence of Cyprinid fishes in the Turolian gypsum of Teruel basin clearly indicates that the sedimentation has taken place in continental waters with low salt-content.

    La révision des Poissons fossiles turoliens de Los Aljezares de Teruel (Espagne conduit à considérer qu'ils appartiennent au genre actuel Rutilus RAFINESQUE. Ces Poissons sont done désignés comme R. pochecoi (ROYO GÓMEZ. La présence de Cyprinidae dans les gypses turoliens du fossé de Teruel indique clairement que le dépôt de ceux-ci s'est produit dans des eaux continentales à faible salinité. La revisión de los peces fósiles turolienses de Los Aljezares de Teruel conduce a considerarlos como pertenecientes al género actual Rutilus RAFINESQUE. Estos peces son designados como R. pochecoi (ROYO GÓMEZ. La presencia de Ciprínidos en los yesos turolienses de la cuenca de Teruel indica claramente que el depósito de éstos se ha producido en aguas continentales de escasa salinidad.

  16. Roost selection by Rafinesque’s big-eared bats (Corynorhinus rafinesquii) in a pristine habitat at three spatial scales

    Science.gov (United States)

    Lucas, Jessica S.; Loeb, Susan C.; Jodice, Patrick G.R.

    2015-01-01

    Although several studies have described roost use by Rafinesque's big-eared bats (Corynorhinus rafinesquii), few studies have examined roost selection. We examined roost use and selection by Rafinesque's big-eared bat at the tree, stand, and landscape scales during the maternity season in pristine old-growth habitat in the Coastal Plain of South Carolina. We located 43 roosts (14 maternity, 29 solitary) through cavity searches and radio-telemetry. Maternity colonies and solitary individuals selected roosts based on similar characteristics. The best model explaining roost selection by all bats included tree and stand characteristics; landscape factors had little influence on roost use. Bats selected large diameter trees in areas with a high density of trees with cavities in the surrounding area. Most roosts (67.4%) were in water tupelo (Nyssa aquatica) in semi-permanently flooded and saturated areas. Half of maternity roost cavities had upper bole openings whereas only 25.8% of solitary roosts had upper bole openings. Bats that roosted with maternity groups stayed in roosts for significantly shorter periods of time (1.3 ± 0.1 days) and used significantly more roost trees (5.0 ± 0.6 roosts) than adult males (3.8 ± 1.10 days, 2.3 ± 0.4 roosts, respectively). Maternity colony use of cavities with upper bole openings and shorter residency times suggest that predator avoidance may have been an important factor governing roosting behavior of maternity colonies in this area. Our results suggest that retention of large diameter, hollow trees in wetland areas will benefit Rafinesque's big-eared bat individuals and maternity colonies in this area.

  17. Endocrine active contaminants in aquatic systems and intersex in common sport fishes

    Science.gov (United States)

    Lee Pow, Crystal S. D.; Law, J. Mac; Kwak, Thomas J.; Cope, W. Gregory; Rice, James A.; Kullman, Seth W.; Aday, D. Derek

    2017-01-01

    Male fish are susceptible to developing intersex, a condition characterized by the presence of testicular oocytes. In the present study, the relationship between intersex and exposure to estrogenic endocrine active contaminants (EACs) was assessed for 2 genera of sport fish, Micropterus and Lepomis, at 20 riverine sites. Seasonal trends and relationships between EACs and intersex (prevalence and severity) were examined at varying putative sources of EACs throughout North Carolina, identified as point sources, nonpoint sources, and reference sites. Intersex was identified in both genera, which was documented for the first time in wild-caught Lepomis. Intersex was more prevalent (59.8%) and more severe (1.6 mean rank) in Micropterus, which was highly correlation to EACs in sediment. In contrast, intersex was less common (9.9%) and less severe (0.2 mean rank) in Lepomis and was highly correlated to EACs in the water column. The authors found that concentrations of polycyclic aromatic hydrocarbons, polychlorinated biphenyls, industrial EACs, and estrogens were highest at point source sites; however, no source type variation was identified in the prevalence or severity of intersex, nor were there seasonal trends in intersex or EAC concentrations. The authors’ results associate genus-specific prevalence of intersex with specific EAC classes in common sport fishes having biological, ecological, and conservation implications.

  18. The length-weight relationships of three sharks and five batoids in the Lebanese marine waters, eastern Mediterranean

    Directory of Open Access Journals (Sweden)

    Myriam Lteif

    2016-12-01

    Full Text Available Length-weight relationships were estimated for 8 elasmobranchs (3 sharks and 5 batoids in the Lebanese marine waters, eastern Mediterranean. The values of parameter b ranged between 1.752 ± 0.4508 and 3.337 ± 0.2321. Sex influenced the length-weight relationships for the shark Centrophorus uyato (Rafinesque 1801 and the batoid Torpedo marmorata (Risso 1810. These relationships should be used only with the observed length ranges.

  19. La familia Ocythoidae (Cephalopoda: Octopoda en el Perú

    Directory of Open Access Journals (Sweden)

    Franz Cardoso

    2014-06-01

    Full Text Available Se revisa la familia Ocythoidae en base a la literatura y material peruano. La familia presenta sólo un género y una especie, Ocythoe tuberculata Rafinesque, 1814. Esta especie es epipelágica y posiblemente cosmopolita en aguas oceánicas cálidas (subtropicales de los Océanos Atlántico, Pacífico e índico y del Mar Mediterráneo. Se presenta información sobre la sistemática y biología de la especie.

  20. Biologia dos Palaemonidae (Crustacea, Decapoda da bacia hidrográfica de Ratones, Florianópolis, Santa Catarina, Brasil Biology of Palaemonidae (Crustacea, Decapoda from the Ratones hidrografic basin, Florianópolis, Santa Catarina, Brazil

    Directory of Open Access Journals (Sweden)

    Yara Maria Rauh Müller

    1999-01-01

    Full Text Available Biological aspects of palemonids, collected from March, 91 to December, 95 in the Ratones Hidrographic Basin, Florianópolis, Santa Catarina, have been investigated. Individuals of different sizes of Macrobrachium acanthurus (Weigmann, 1836, Macrobrachium carcinus (Linnaeus, 1758, Macrobrachium olfersii (Weigmann, 1836, Macrobrachium potiuna (Müller, 1880, Palaemonetes argentinus Nobili, 1901 and Palaemon pandaliformis (Stimpson, 1871 were registered. These prawns, showed reproductive strategies, typical of the Palaemonidae (Rafinesque, 1815, associated to species particularities, and seem to adapt to different environmental conditions.

  1. Update on the distribution of the invasive Asian fish tapeworm, Bothriocephalus acheilognathi, in the U.S. and Canada

    Science.gov (United States)

    Choudhury, A.; Charipar, E.; Nelson, P.; Hodgson, J.R.; Bonar, S.; Cole, Rebecca A.

    2006-01-01

    The documented range of the invasive and potentially pathogenic Asian fish tapeworm, Bothriocephalus acheilognathi Yamaguti, 1934 in the United States and Canada is updated based on examination of museum depositions and original field collections. Gravid specimens of B. acheilognathi were collected from the fathead minnow Pimephales promelas Rafinesque in Peter Lake, at the University of Notre Dame Environmental Research Center (UNDERC) Land o' Lakes, Wisconsin. A single immature specimen of the parasite was collected from a white bass, Morone chrysops (Rafinesque) in Lake Winnipeg, Manitoba, Canada. This is the first record of B. acheilognathi in Canada and extends its northern range in the interior of the continent by more than 600 miles over the last documented record. The previous record of B. acheilognathi in Canada, from the northern pikeminnow, Ptychocheilus oregonensis in British Columbia, is a misidentification of Eubothrium tulipai. Examination of selected records of intestinal cestodes from native cyprinids, in the Harold W. Manter Laboratory of Parasitology (HWML, n = 9) collection and in the United States National Parasite Collection (USNPC, n = 8), provided evidence of the parasite in Nebraska and possibly in the upper Colorado River basin. Introductions into Wisconsin-Michigan were due to the stocking of golden shiners, whereas the source of the introduction in Manitoba remains unknown.

  2. Bats of the Savannah River Site and vicinity.

    Energy Technology Data Exchange (ETDEWEB)

    M.A. Menzel; J.M. Menzel; J.C. Kilgo; W.M. Ford; T.C. Carter; J.W. Edwards

    2003-10-01

    The U.S. Department of Energy's Savannah River Site supports a diverse bat community. Nine species occur there regularly, including the eastern pipistrelle (Pipistrellus subflavus), southeastern myotis (Myotis austroriparius), evening bat (Nycticeius humeralis), Rafinesque's big-eared bat (Corynorhinus rafinesquii), silver-haired bat (Lasionycteris noctivagans), eastern red bat (Lasiurus borealis), Seminole bat (L. seminolus), hoary bat (L. cinereus), and big brown bat (Eptesicus fuscus). There are extralimital capture records for two additional species: little brown bat (M. lucifigus) and northern yellow bat (Lasiurus intermedius). Acoustical sampling has documented the presence of Brazilian free-tailed bats (Tadarida brasiliensis), but none has been captured. Among those species common to the Site, the southeastern myotis and Rafinesque's big-eared bat are listed in South Carolina as threatened and endangered, respectively. The presence of those two species, and a growing concern for the conservation of forest-dwelling bats, led to extensive and focused research on the Savannah River Site between 1996 and 2002. Summarizing this and other bat research, we provide species accounts that discuss morphology and distribution, roosting and foraging behaviors, home range characteristics, habitat relations, and reproductive biology. We also present information on conservation needs and rabies issues; and, finally, identification keys that may be useful wherever the bat species we describe are found.

  3. Transfer of 65Zn from natural and synthetic foods to a freshwater fish

    International Nuclear Information System (INIS)

    Merlini, M.; Pozzi, G.; Brazzelli, A.; Berg, A.

    1976-01-01

    Lepomis gibbosus, L. from Lago Maggiore, North Italy, were fed marked laboratory-made ''synthetic'' food or the soft tissues of the snail Viviparus ater (Cristofori and Jan) which had accumulated 65 Zn from lake water prior to the experiment. Other groups of the fish, maintained in water with 65 ZnCl 2 , were fed unmarked synthetic food or nonradioactive snail tissues (natural food). The transfer of radiozinc was greater from food than from water. In addition, it appears that accumulation of the radioelement by fish is dependent upon its physico-chemical state which, in turn, depends on the type of food eaten

  4. Population characteristics of channel catfish near the northern edge of their distribution: implications for management

    Science.gov (United States)

    Carter-Lynn, K. P.; Quist, Michael C.

    2015-01-01

    Channel catfish, Ictalurus punctatus (Rafinesque), populations in six lakes in northern Idaho, USA, were sampled to describe their population characteristics. During the summers of 2011 and 2012, 4864 channel catfish were sampled. Channel catfish populations had low to moderate catch rates, and length structure was dominated by fish Channel catfish were in good body condition. All populations were maintained by stocking age-1 or age-2 fish. Growth of fish reared in thermally enriched environments prior to stocking was fast compared to other North American channel catfish populations. After stocking, growth of channel catfish declined rapidly. Once stocked, cold water temperatures, prey resources and (or) genetic capabilities limited growth. Total annual mortality of age 2 and older channel catfish was generally channel catfish population dynamics and highlights important considerations associated with their ecology and management.

  5. An annotated catalogue of the type material of Elateroidea Leach, 1815 (Coleoptera) deposited in the Coleoptera collection of the Museum of Zoology of the University of São Paulo, Brazil.

    Science.gov (United States)

    Ferreira, Vinicius De Souza

    2015-03-25

    The Museum of Zoology of the University of São Paulo (MZSP) houses one of the most important Coleoptera collections of Brazil and Neotropical Region with nearly 900,000 adult mounted material and about 1,500,000 specimens to be mounted. The superfamily Elateroidea Leach, 1815 (including Cantharoidea) comprises about 24,077 described species in 17 families. The MZSP owns type material of Brachypsectridae LeConte & Horn, 1883, Cantharidae, 1856 (1815), Cerophytidae Latreille, 1834, Elateridae Leach 1815, Eucnemidae Eschscholtz, 1829, Lampyridae Rafinesque, 1815, Lycidae Laporte, 1836, Phengodidae LeConte, 1861 and Rhinorhipidae Lawrence, 1988. This catalogue includes type material of 166 species distributed in 69 genera. Among 1,223 type specimens, are 86 holotypes, 1,133 paratypes, 2 allotypes, 1 lectotype and 1 paralectotype.

  6. First report of pigmentation dystrophy in terrestrial isopods, Atlantoscia floridana (van Name (Isopoda, Oniscidea, induced by larval acanthocephalans

    Directory of Open Access Journals (Sweden)

    Amato José F. R.

    2003-01-01

    Full Text Available The observation of pigmentation alteration in isopod crustaceans induced by acanthocephalans, known as pigmentation dystrophy, has been documented in North America in species of the aquatic genera Asellus Geoffroy, 1764, Lirceus Rafinesque-Schmaltz, 1820, and Caecidotea Packard, 1871, and in Europe, in Asellus. Recently, three depigmented specimens of Atlantoscia floridana (van Name, 1940, a terrestrial isopod, occurring from >Florida, USA to northern Argentina were found showing pigmentation dystrophy and harboring larval acanthocephalans. Photographic documentation of live and preserved, infected isopods is presented. Morphometric data and photomicrographs of the male, unencysted cystacanth specimen which allowed its placement in the genus Centrorhynchus Lühe, 1911 are presented. This is the first record of the phenomenon of pigmentation dystrophy in terrestrial isopod crustaceans, the first record of A. floridana infected by an acanthocephalan and the first record of a species of Centrorhynchus in a terrestrial isopod.

  7. Reservoir competence of Microtus pennsylvanicus (Rodentia: Cricetidae) for the Lyme disease spirochete, Borrelia burgdorferi

    Science.gov (United States)

    Markowski, D.; Ginsberg, H.S.; Hyland, K.E.; Hu, R.

    1998-01-01

    The reservoir competence of the meadow vole, Microtus pennsylvanicus Ord, for the Lyme disease spirochete, Borrelia burgdorferi Johnson, Schmid, Hyde, Steigerwalt & Brenner was established on Patience Island, RI. Meadow voles were collected from 5 locations throughout Rhode Island. At 4 of the field sites, M. pennsylvanicus represented only 4.0% (n = 141) of the animals captured. However, on Patience Island, M. pennsylvanicus was the sole small mammal collected (n = 48). Of the larval Ixodes scapularis Say obtained from the meadow voles on Patience Island, 62% (n = 78) was infected with B. burgdorferi. Meadow voles from all 5 locations were successfully infected with B. burgdorferi in the laboratory and were capable of passing the infection to xenodiagnostic I. scapularis larvae for 9 wk. We concluded that M. pennsylvanicus was physiologically capable of maintaining B. burgdorferi infection. However, in locations where Peromyscus leucopus (Rafinesque) is abundant, the role of M. pennsylvanicus as a primary reservoir for B. burgdorferi was reduced.

  8. The unionid (Bivalvia) fauna of the Sipsey River in northwestern Alabama, an aquatic hotspot

    Science.gov (United States)

    McCullagh, W. Henry; Williams, James D.; McGregor, Stuart W.; Pierson, J. Malcom; Lydeard, Charles

    2002-01-01

    Recent surveys for unionid bivalves were conducted in the mainstem of the Sipsey River and headwater tributaries (Tombigbee River drainage) during the summer and autumn of 1996-1999. A total of 35 species and 22 genera were found. Museum records from the upper Sipsey, based largely on the efforts of H. H. Smith during 1910-11, raised the total number of recorded unionids in the Sipsey to 42. Smith documented 25 species in the river; however, most of his collections were made in the mid- to upper-Sipsey, which has lower diversity. The three most common recently observed species in descending order of abundance were Quadrula asperata (I. Lea, 1861), Pleurobema decisum (I. Lea, 1831), and Tritogonia verrucosa (Rafinesque, 1820). Federally listed species observed recently include Lampsilis perovalis (Conrad, 1834) (threatened), Medionidus acutissimus (I. Lea, 1831) (threatened), P. decisum (endangered), P. perovatum (Conrad, 1834) (endangered), and Potamilus inflatus (I. Lea, 1831) (threatened). Species not observed recently but recorded in prior surveys include Anodontoides radiatus (Conrad, 1834), Arcidens confragosus (Say, 1829), Plectomerus dombeyanus (Valenciennes, 1827), Q. metanevra (Rafinesque, 1820), Q. stapes (I. Lea, 1831) (federally endangered), P. taitianum (I. Lea, 1834) (federally endangered), and Toxolasma parvus (Barnes, 1823). Many, species are known recently or historically by only five or fewer recorded specimens including: A. radiatus, Elliptio arctata (Conrad, 1834), Ligumia recta (Lamarck, 1819), P. taitianum, P. inflatus, Q. aspera (Lea, 1831), Q. metanevra, Q. stapes, T. parvus, Truncilla donaciformis (I. Lea, 1828), Uniomerus tetralasmus (Say, 1831), Utterbackia imbecillis (Say, 1829), A. confragosus, and P. dombeyanus. Unlike the mussel fauna of most Alabama streams, that of the Sipsey River is still relatively intact in terms of species richness despite impacts from mining, silvicultural, and agricultural activities. A concerted effort

  9. Prosthenystera oonastica n. sp. (Digenea: Callodistomidae) from ictalurid catfishes in southeastern United States and molecular evidence differentiating species in the genus across Americas.

    Science.gov (United States)

    Tkach, Vasyl V; Curran, Stephen S

    2015-01-01

    Prosthenhystera oonastica n. sp. is described as a cryptic species from the gall bladder of three ictalurid catfishes, Ictalurus punctatus (Rafinesque), Ictalurus furcatus (Valenciennes), and Pylodictis olivaris (Rafinesque), in rivers in the southeastern United States. The species was originally named by Wilmer A. Rogers in 1979 but never formally described. Material used for the description consists of two specimens of Roger's original material and ten new specimens. We found no significant morphological features that are useful for discriminating between the new species and its closest relative Prosthenhystera obesa (Diesing, 1850) Travassos, 1922 that occurs in the gall bladders of freshwater characiform, perciform and siluriform fishes, ranging from South America to southern Mexico. However, we found substantial differences in the large subunit ribosomal DNA (partial 28S rRNA gene) between the two species justifying the naming of the new species. Prosthenhystera oonastica n. sp. is readily differentiated from Prosthenhystera caballeroi Jiménez-Guzmán, 1973 that occurs in the gall bladders of characid fishes in Central America and Mexico, by having a relatively straight or bent rather than highly convoluted oesophagus, a relatively smaller ovary, smaller and less coalesced vitelline follicles, narrower caeca and smaller eggs. Comparison of ribosomal DNA (partial ITS1, 5.8S, ITS2, and partial 28S gene) between P. oonastica n. sp. and P. caballeroi revealed large differences between the two species. Phylogenetic analysis based on partial 28S rRNA gene sequences from the three studied species of Prosthenhystera Travassos, 1922 and related digenean taxa revealed a closer relationship between P. oonastica n. sp. and P. obesa than either has had with P. caballeroi.

  10. Effects of predatory fish on survival and behavior of larval gopher frogs (Rana capito) and Southern Leopard Frogs (Rana sphenocephala)

    Science.gov (United States)

    Gregoire, D.R.; Gunzburger, M.S.

    2008-01-01

    Southern Leopard Frogs, Rana sphenocephala, are habitat generalists occurring in virtually all freshwater habitats within their geographic range, whereas Gopher Frogs, Rana capito, typically breed in ponds that do not normally contain fish. To evaluate the potential for predation by fish to influence the distribution of these species, we conducted a randomized factorial experiment. We examined the survival rate and behavior of tadpoles when exposed to Warmouth Sunfish, Lepomis gulosus, Banded Sunfish, Enneacanthus obesus, and Eastern Mosquitofish, Gambusia holbrooki. We also conducted a choice experiment to examine the survival rate of the two species of tadpoles when a predator is given a choice of both species simultaneously. Lepomis gulosus consumed the most tadpoles and ate significantly more tadpoles of R. capito than R. sphenocephala. Gambusia holbrooki injured the most tadpoles, especially R. capito. Enneacanthus obesus did not have an effect on behavior or survival of either anuran species. Tadpoles of both anurans increased hiding when in the presence of L. gulosus and G. holbrooki, but a greater proportion of R. capito hid than did R. sphenocephala. Our results suggest that R. capito are more vulnerable to predation by fish than are R. sphenocephala. The introduction of fish may play a role in population declines of certain anurans breeding in normally fish-free wetlands, and even small fish, such as mosquitofish, may have significant negative effects on the tadpoles of R. capito. Copyright 2008 Society for the Study or Amphibians and Reptiles.

  11. A molecular genetic examination of the mating system of pumpkinseed sunfish reveals high pay-offs for specialized sneakers.

    Science.gov (United States)

    Rios-Cardenas, Oscar; Webster, Michael S

    2008-05-01

    Intrasexual variation in reproductive behaviour and morphology are common in nature. Often, such variation appears to result from conditional strategies in which some individuals (e.g. younger males or those in poor condition) adopt a low pay-off phenotype as a 'best of a bad job'. Alternatively, reproductive polymorphisms can be maintained by balancing selection, with male phenotypes having equal fitnesses at equilibrium, but examples from nature are rare. Many species of sunfish (genus Lepomis) are thought to have alternative male reproductive behaviours, but most empirical work has focused on the bluegill sunfish and the mating systems of other sunfish remain poorly understood. We studied a population of pumpkinseed sunfish (Lepomis gibbosus) in upstate New York. Field observations confirm the existence of two male reproductive strategies: 'parentals' were relatively old and large males that maintained nests, and 'sneakers' were relatively young and small males that fertilize eggs by darting into nests of parentals during spawning. The sneaker and parental male strategies appear to be distinct life-history trajectories. Sneaker males represented 39% of the males observed spawning, and sneakers intruded on 43% of all mating attempts. Microsatellite analyses revealed that sneaker males fertilized an average of 15% of the eggs within a nest. This level of paternity by sneaker males appears to be higher than seen in most other fishes, and preliminary analyses suggest that the two male reproductive strategies are maintained as a balanced polymorphism.

  12. Distinguishing centrarchid genera by use of lateral line scales

    Science.gov (United States)

    Roberts, N.M.; Rabeni, C.F.; Stanovick, J.S.

    2007-01-01

    Predator-prey relations involving fishes are often evaluated using scales remaining in gut contents or feces. While several reliable keys help identify North American freshwater fish scales to the family level, none attempt to separate the family Centrarchidae to the genus level. Centrarchidae is of particular concern in the midwestern United States because it contains several popular sport fishes, such as smallmouth bass Micropterus dolomieu, largemouth bass M. salmoides, and rock bass Ambloplites rupestris, as well as less-sought-after species of sunfishes Lepomis spp. and crappies Pomoxis spp. Differentiating sport fish from non-sport fish has important management implications. Morphological characteristics of lateral line scales (n = 1,581) from known centrarchid fishes were analyzed. The variability of measurements within and between genera was examined to select variables that were the most useful in further classifying unknown centrarchid scales. A linear discriminant analysis model was developed using 10 variables. Based on this model, 84.4% of Ambloplites scales, 81.2% of Lepomis scales, and 86.6% of Micropterus scales were classified correctly using a jackknife procedure. ?? Copyright by the American Fisheries Society 2007.

  13. An annotated distributional checklist of exotic freshwater fishes from the Baja California Peninsula, Mexico Lista comentada sobre la distribución de peces dulceacuícolas exóticos de la península de Baja California, México

    Directory of Open Access Journals (Sweden)

    Gorgonio Ruiz-Campos

    2012-03-01

    Full Text Available We documented the distributional status of 27 exotic fish species in the inland waters of the Baja California Peninsula, Mexico, based on voucher specimens collected from 122 sites between 1977 and 2010, and on published records. The species reported here are representatives of genera from the Atlantic drainages of North America (Ictalurus, Ameiurus, Pylodictis, Morone, Lepomis, Pomoxis, Dorosoma, Cyprinella, and Micropterus, Middle America (Poecilia, Gambusia, and Xiphophorus, Eurasia (Cyprinus and Carassius, and Africa (Tilapia and Oreochromis. The family containing the highest number of species is Centrarchidae (7 species followed by Ictaluridae and Poeciliidae (6 species each. Four species were determined to be invasive due to their wide distribution and fast dispersal through the Peninsula (Gambusia affinis, Poecilia reticulata, Lepomis cyanellus, and Tilapia sp. cf. zillii. We analyze the impacts of exotic species on the native populations of 3 species with problems of conservation: Cyprinodon macularius (endangered, Fundulus lima (endangered, and Gasterosteus aculeatus (vulnerable. Alien fishes have been introduced for a variety of reasons in Mexico: ornament, sport, aquaculture, biological control, and by accident. In some cases fish introductions were carried out for more than one reason.El estatus de la distribución de peces exóticos es documentado para 27 especies en las aguas continentales de la península de Baja California, México, basado en registros de ejemplares recolectados en 122 localidades durante el período de 1977 a 2010, así como registros referidos en la literatura. Las especies aquí reportadas son representativas de géneros que proceden de la vertiente Atlántica de Norteamérica (Ictalurus, Ameiurus, Pylodictis, Morone, Lepomis, Pomoxis, Dorosoma, Cyprinella y Micropterus, Mesoamérica (Poecilia, Gambusia y Xiphophorus, Eurasia (Cyprinus y Carassius y África (Tilapia y Oreochromis. La familia con mayor n

  14. Teratogenic effects and monetary cost of selenium poisoning of fish in Lake Sutton, North Carolina.

    Science.gov (United States)

    Lemly, A Dennis

    2014-06-01

    Selenium pollution from coal ash wastewater was investigated in Lake Sutton, NC. This lake has been continuously used as a cooling pond for a coal-fired power plant since 1972. Historic and recent levels of contamination in fish tissues (14-105µg Se/g dry weight in liver, 24-127 in eggs, 4-23 in muscle, 7-38 in whole-body) exceeded toxic thresholds and teratogenic effects were observed in fish collected in 2013. A high proportion (28.9 percent) of juvenile Lepomis spp. exhibited spinal and craniofacial malformations that were consistent with selenium poisoning. Teratogenic Deformity Index values indicated population-level impacts on the fishery. The partially monetized cost of resultant fishery losses was calculated at over $US 8.6 million annually, and over $US 217 million for the entire period of damage, which dates back to 1987 when chemical and biological monitoring began. Published by Elsevier Inc.

  15. Effects of a non-native cichlid fish (African jewelfish, Hemichromis letourneuxi Sauvage 1880) on a simulated Everglades aquatic community

    Science.gov (United States)

    Schofield, Pamela J.; Slone, Daniel H.; Gregoire, Denise R.; Loftus, William F.

    2014-01-01

    In an 8-month mesocosm experiment, we examined how a simulated Everglades aquatic community of small native fishes, snails, and shrimp changed with the addition of either a native predator (dollar sunfish Lepomis marginatus) or a non-native predator (African jewelfish Hemichromis letourneuxi) compared to a no-predator control. Two snail species (Planorbella duryi, Physella cubensis) and the shrimp (Palaemonetes paludosus) displayed the strongest predator-treatment effects, with significantly lower biomasses in tanks with Hemichromis. One small native fish (Heterandria formosa) was significantly less abundant in Hemichromis tanks, but there were no significant treatment effects for Gambusia holbrooki, Jordanella floridae, or Pomacea paludosa (applesnail). Overall, there were few treatment differences between native predator and no-predator control tanks. The results suggest that the potential of Hemichromis to affect basal food-web species that link primary producers with higher-level consumers in the aquatic food web, with unknown consequences for Florida waters.

  16. Toxicity of synthetic musks to early life stages of the freshwater mussel Lampsilis cardium

    Science.gov (United States)

    Gooding, M.P.; Newton, T.J.; Bartsch, M.R.; Hornbuckle, K.C.

    2006-01-01

    Polycyclic musk fragrances are common additives to many consumer products. As a result of their widespread use and slow degradation rates, they are widely found in aquatic environments. This study reports on the lethal and sublethal toxicity of the polycyclic musks AHTN (Tonalide??) and HHCB (Galaxolide??) to glochidial (larval) and juvenile life stages of the freshwater mussel Lampsilis cardium (Rafinesque, 1820). In glochidia, 24-h median lethal concentrations (LC50s) ranged from 454 to 850 ??g AHTN/L and from 1000 to >1750 ??g HHCB/L (water solubility). Results for 48-h tests were similar to the 24-h tests. In 96-h tests with juveniles, we did not observe a dose-response relation between mortality and either musk. However, the growth rate was reduced by musk exposure. The median effective concentrations (EC50s, based on growth) were highly variable and ranged from 108 to 1034 ??g AHTN/L and 153 to 831 ??g HHCB/L. While all adverse effects occurred at concentrations that are much greater than those reported in natural waters (low ??g/L to ng/L), these results indicate the potential for adverse effects on these long-lived organisms from exposure to synthetic musk fragrances. ?? 2006 Springer Science+Business Media, Inc.

  17. C and N Stable Isotope Variability in Soft Tissue of Invasive Species Ficopomatus enigmaticus (Annelida, Polychaeta)

    International Nuclear Information System (INIS)

    Cukrov, Neven; Cukrov, Marijana; Lojen, Sonja

    2011-01-01

    Serpulidae Rafinesque, 1815 is a family of polychaete annelids with calcareous tubes found in worldwide from littoral to abyssal depths. Of more than 350 described species of serpulid polychaetes, Marifugia cavatica Absolon and Hrabe 1930 is the only known cave-dwelling stygobiotic and freshwater serpulid, five other serpulid species comprising the genus Ficopomatus are found in brackish water, otherwise serpulids are all marine organisms. Ficopomatus enigmaticus (Fauvel, 1923), previously known as Mercierella enigmatica, is a truly cosmopolitan with disjunct distribution. It has been found worldwide inhabiting coastal brackish waters, lagoons and estuaries of warm temperate areas of both hemispheres. This tubeworm builds calcareous tubes on any hard substrate. With distinctive collar-like rings at irregular intervals it is relatively easy to identify. It is an efficient suspension-feeder, very tolerant and physiologically well adapted to temperature and salinity variations, eutrophic conditions and low dissolved oxygen content. The fact that populations of F. enigmaticus appear near the ports suggests that the probable mechanism of introduction was ship fouling or ballast water. Generally, F. enigmaticus is considered as a fouling nuisance species which negatively affects ships, buoys and harbour structures.

  18. Presencia de Trachemys Agassiz, 1857 (Testudines, Emydidae en el Pleistoceno tardío del centro de la Argentina

    Directory of Open Access Journals (Sweden)

    Cabrera, Mario R.

    2011-08-01

    Full Text Available En este trabajo se describen restos del caparazón de una tortuga que constituyen el primer registro del género dulceacuícola Trachemys Agassiz, 1857 y de la familia Emydidae Rafinesque, 1815 en la provincia de Córdoba, y el hallazgo más occidental de ambos en la Argentina. Los materiales recuperados consisten en la placa proneural, las placas pleurales IV y VIII derechas y fragmentos de las placas pleurales III y IV izquierdas, epiplastron, hioplastron e hipoplastron derechos, más tres fragmentos indeterminables. Los restos provienendel Sitio El Silencio (30°53’20" S, 62°49’29" W, un yacimiento paleontológico de edad Pleistoceno tardío - Holoceno temprano, expuesto en la costa de la actual laguna Mar Chiquita, en un nivel de limo con intercalaciones de carbonato de calcio asignado a la Formación Tezanos Pinto, cuya depositación se produjo entre los 36.000 y 8.000 AP. El registro esrelacionado con un evento húmedo acontecido entre los 16.500 y 15.500 años AP, que pudo haber sido lo suficientemente marcado y sostenido como para posibilitar el ingreso deTrachemys (y otros taxones vertebrados durante el Pleistoceno a cercanías de la laguna Mar Chiquita, unos 220 km hacia el oeste de su distribución actual.

  19. Cannibalistic-morph Tiger Salamanders in unexpected ecological contexts

    Science.gov (United States)

    McLean, Kyle I.; Stockwell, Craig A.; Mushet, David M.

    2016-01-01

    Barred tiger salamanders [Ambystoma mavortium (Baird, 1850)] exhibit two trophic morphologies; a typical and a cannibalistic morph. Cannibalistic morphs, distinguished by enlarged vomerine teeth, wide heads, slender bodies, and cannibalistic tendencies, are often found where conspecifics occur at high density. During 2012 and 2013, 162 North Dakota wetlands and lakes were sampled for salamanders. Fifty-one contained A. mavortium populations; four of these contained cannibalistic morph individuals. Two populations with cannibalistic morphs occurred at sites with high abundances of conspecifics. However, the other two populations occurred at sites with unexpectedly low conspecific but high fathead minnow [Pimephales promelas (Rafinesque, 1820)] abundances. Further, no typical morphs were observed in either of these later two populations, contrasting with earlier research suggesting cannibalistic morphs only occur at low frequencies in salamander populations. Another anomaly of all four populations was the occurrence of cannibalistic morphs in permanent water sites, suggesting their presence was due to factors other than faster growth allowing them to occupy ephemeral habitats. Therefore, our findings suggest environmental factors inducing the cannibalistic morphism may be more complex than previously thought.

  20. Accelerometer-derived activity correlates with volitional swimming speed in lake sturgeon (Acipenser fulvescens)

    Science.gov (United States)

    Thiem, J.D.; Dawson, J.W.; Gleiss, A.C.; Martins, E.G.; Haro, Alexander J.; Castro-Santos, Theodore R.; Danylchuk, A.J.; Wilson, R.P.; Cooke, S.J.

    2015-01-01

    Quantifying fine-scale locomotor behaviours associated with different activities is challenging for free-swimming fish.Biologging and biotelemetry tools can help address this problem. An open channel flume was used to generate volitionalswimming speed (Us) estimates of cultured lake sturgeon (Acipenser fulvescens Rafinesque, 1817) and these were paired withsimultaneously recorded accelerometer-derived metrics of activity obtained from three types of data-storage tags. This studyexamined whether a predictive relationship could be established between four different activity metrics (tail-beat frequency(TBF), tail-beat acceleration amplitude (TBAA), overall dynamic body acceleration (ODBA), and vectorial dynamic body acceleration(VeDBA)) and the swimming speed of A. fulvescens. Volitional Us of sturgeon ranged from 0.48 to 2.70 m·s−1 (0.51–3.18 bodylengths (BL) · s−1). Swimming speed increased linearly with all accelerometer-derived metrics, and when all tag types werecombined, Us increased 0.46 BL·s−1 for every 1 Hz increase in TBF, and 0.94, 0.61, and 0.94 BL·s−1 for every 1g increase in TBAA,ODBA, and VeDBA, respectively. Predictive relationships varied among tag types and tag-specific parameter estimates of Us arepresented for all metrics. This use of acceleration data-storage tags demonstrated their applicability for the field quantificationof sturgeon swimming speed.

  1. Complex influences of low-head dams and artificial wetlands on fishes in a Colorado River tributary system

    Science.gov (United States)

    Beatty, R.J.; Rahel, F.J.; Hubert, W.A.

    2009-01-01

    Low-head dams in arid regions restrict fish movement and create novel habitats that have complex effects on fish assemblages. The influence of low-head dams and artificial wetlands on fishes in Muddy Creek, a tributary of the Colorado River system in the USA was examined. Upstream, fish assemblages were dominated by native species including two species of conservation concern, bluehead sucker, Catostomus discobolus Cope, and roundtail chub, Gila robusta Baird and Girard. The artificial wetlands contained almost exclusively non-native fathead minnow, Pimephales promelas Rafinesque, and white sucker, Catostomus commersonii (Lacep??de). Downstream, fish assemblages were dominated by non-native species. Upstream spawning migrations by non-native white suckers were blocked by dams associated with the wetlands. However, the wetlands do not provide habitat for native fishes and likely inhibit fish movement. The wetlands appear to be a source habitat for non-native fishes and a sink habitat for native fishes. Two non-native species, sand shiner, Notropis stramineus (Cope), and redside shiner, Richardsonius balteatus (Richardson), were present only downstream of the wetlands, suggesting a beneficial role of the wetlands in preventing upstream colonisation by non-native fishes. ?? 2009 Blackwell Publishing Ltd.

  2. Spillover of the Atlantic bluefin tuna offspring from cages in the Adriatic Sea: A multidisciplinary approach and assessment.

    Directory of Open Access Journals (Sweden)

    Tomislav Džoić

    Full Text Available During routine monitoring of commercial purse seine catches in 2011, 87 fingerling specimens of scombrids were collected in the southern Adriatic Sea. Sequencing of the mitochondrial DNA control region locus inferred that specimens belonged to the Atlantic bluefin tuna, Thunnus thynnus (Linnaeus, 1758 (N = 29, bullet tuna, Auxis rochei (Risso, 1810 (N = 30 and little tunny, Euthynnus alletteratus, Rafinesque, 1810 (N = 28. According to previously published growth parameters, the age of the collected specimens was estimated at approximately 30-40 days, suggesting they might have been spawned in the Adriatic Sea, contrary to the current knowledge. A coupled modelling system with hydrodynamic (ROMS and individual based model (IBM-Ichthyop was set up to determine the location of the spawning event. Numerical simulations with the IBM model, both backward and forward in time, indicate commercial tuna cages in the middle Adriatic coastal area as possible spawning location. The two other non-commercial species likely opportunistically use the positive environmental (abiotic and biotic conditions to spawn in the same area.

  3. Using constructed wetlands to treat biochemical oxygen demand and ammonia associated with a refinery effluent.

    Science.gov (United States)

    Huddleston, G M; Gillespie, W B; Rodgers, J H

    2000-02-01

    This study evaluated the effectiveness of constructed wetlands for tertiary treatment of a petroleum refinery effluent. Specific performance objectives were to decrease 5-day biochemical oxygen demand (BOD(5)) and ammonia by at least 50% and to reduce toxicity associated with this effluent. Two bench-scale wetlands (replicates) were constructed in a greenhouse to provide tertiary treatment of effluent samples shipped from the refinery to the study site. Integrated wetland features included Typha latifolia Linnaeus planted in low organic (0.2%), sandy sediment, 48-h nominal hydraulic retention time, and 15-cm overlying water depth. Targeted constituents and aqueous toxicity were monitored in wetland inflows and outflows for 3 months. Following a 2 to 3-week stabilization period, effective and consistent removal of BOD(5) and ammonia (as NH(3)-N) from the effluent was observed. Average BOD(5) removal was 80%, while NH(3)-N decreased by an average of 95%. Survival of Pimephales promelas Rafinesque and Ceriodaphnia dubia Richard (7-day, static, renewal exposures) increased by more than 50% and 20%, respectively. Reproduction of C. dubia increased from zero in undiluted wetland inflow to 50% of controls in undiluted wetland outflow. This study demonstrated the potential for constructed wetlands to decrease BOD(5), ammonia, and toxicity in this refinery effluent. Copyright 2000 Academic Press.

  4. Evaluation of a cohabitation challenge model in immunization trials for channel catfish Ictalurus punctatus against Ichthyophthirius multifiliis.

    Science.gov (United States)

    Xu, De-Hai; Klesius, Phillip H; Shoemaker, Craig A

    2007-02-08

    Calcein marking and cohabitation challenges have not been investigated in fish parasite research. This study evaluated a cohabitation challenge method in immunization trials against Ichthyophthirius multifiliis (Ich) using calcein, a fluorescent dye, to mark channel catfish Ictalurus punctatus (Rafinesque). Fish were marked by calcein immersion at 0, 500, and 1500 mg l(-1), and then challenged with 15 000 theronts fish(-1). No difference was noted in fish infection levels, mortality, and mean days to death (MDD) caused by Ich between unmarked and marked fish or between fish marked with high (1500 mg l(-1)) and low (500 mg l(-1)) concentrations of calcein. After ensuring that calcein marking had no effect on the susceptibility of fish to Ich theronts, 2 immunization trials were conducted to evaluate the cohabitation challenge model using calcein-marked catfish. Fish mortality, relative percent survival (RPS), and MDD were compared between cohabitation-challenged fish and fish challenged by non-cohabitation. No significant difference was observed in RPS for cohabitation-challenged fish and fish challenged by non-cohabitation. A cohabitation challenge can be used as an alternative challenge method in parasite studies, since it closely mimics natural exposure.

  5. Trophic niche overlap between flatfishes in a nursery area on the Portuguese coast

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    Henrique N. Cabral

    2002-09-01

    Full Text Available The diets and the trophic niche overlap between seven flatfish species were studied in a coastal nursery adjoining to the Tagus estuary (Portugal. Fish were sampled monthly, from March to November 1999, using a beach seine. Arnoglossus imperialis (Rafinesque, 1810, Arnoglossus laterna (Walbaum, 1792 and Arnoglossus thori Kyle, 1913, fed mainly on crustaceans. The diets of Buglossidium luteum (Risso, 1810 and Dicologoglossa cuneata (Moreau, 1881 were mainly composed of Bivalvia and Polychaeta, while for Scophthalmus rhombus (Linnaeus, 1758 the main food items were Mysidacea and Teleostei. The diet of Pegusa lascaris (Risso, 1810 was mainly composed by Cumacea, Bivalvia, Decapoda and Amphipoda. Based on diet similarities two main groups were identified: one composed of A. imperialis, A. laterna, A. thori and S. rhombus, and the other grouping B. luteum, P. lascaris and D. cuneata. For the most common flatfishes, a similar pattern of diet seasonal variation was found, such that Amphipoda presented higher indices values in the period from March to June, while from July to November, Decapoda were more abundant. Although high values of diet overlap were obtained among some of the species, the main items in the diet of flatfishes are probably the most abundant prey in this coastal area, which suggests a generalist and opportunistic utilization of these food resources. Furthermore, niche overlap between these species is probably minimized by differences in resource use in other niche dimensions, namely time and space.

  6. Spillover of the Atlantic bluefin tuna offspring from cages in the Adriatic Sea: A multidisciplinary approach and assessment

    Science.gov (United States)

    2017-01-01

    During routine monitoring of commercial purse seine catches in 2011, 87 fingerling specimens of scombrids were collected in the southern Adriatic Sea. Sequencing of the mitochondrial DNA control region locus inferred that specimens belonged to the Atlantic bluefin tuna, Thunnus thynnus (Linnaeus, 1758) (N = 29), bullet tuna, Auxis rochei (Risso, 1810) (N = 30) and little tunny, Euthynnus alletteratus, Rafinesque, 1810 (N = 28). According to previously published growth parameters, the age of the collected specimens was estimated at approximately 30–40 days, suggesting they might have been spawned in the Adriatic Sea, contrary to the current knowledge. A coupled modelling system with hydrodynamic (ROMS) and individual based model (IBM—Ichthyop) was set up to determine the location of the spawning event. Numerical simulations with the IBM model, both backward and forward in time, indicate commercial tuna cages in the middle Adriatic coastal area as possible spawning location. The two other non-commercial species likely opportunistically use the positive environmental (abiotic and biotic) conditions to spawn in the same area. PMID:29190825

  7. Peracetic acid is effective for controlling fungus on channel catfish eggs.

    Science.gov (United States)

    Straus, D L; Meinelt, T; Farmer, B D; Mitchell, A J

    2012-07-01

    Peracetic acid (PAA) is a relatively new compound suggested for use to treat pathogens in aquaculture. It is approved for use in Europe, but not in the United States. This study determined the effectiveness of PAA for fungus control on channel catfish, Ictalurus punctatus (Rafinesque), eggs. The study consisted of five PAA concentrations (2.5, 5, 10, 15 and 20mgL(-1) ) and an untreated control in a flow-through system. A single spawn was used for each replication (N =4). Eggs were treated twice daily until the embryos developed eyes. When hatching was complete for all viable eggs, fry were counted to determine the percent survival in each treatment. Fungal growth was severe in the untreated controls resulting in 11% survival. Treatments of 2.5, 5 and 10mgL(-1) PAA were significantly different from the controls (Peggs. The mean survivals in the 0, 2.5, 5, 10, 15 and 20mgL(-1) PAA treatments were 11%, 60%, 63%, 62%, 32% and 0%, respectively. Therefore, PAA may be a compound that merits further investigations regarding its use in U.S. aquaculture. Published 2012. This article is a US Government work and is in the public domain in the USA.

  8. Conservation genetics of managed ungulate populations

    Science.gov (United States)

    Scribner, Kim T.

    1993-01-01

    Natural populations of many species are increasingly impacted by human activities. Perturbations are particularly pronunced for large ungulates due in part to sport and commercial harvest, to reductions and fragmentation of native habitat, and as the result of reintroductions. These perturbations affect population size, sex and age composition, and population breeding structure, and as a consequence affect the levels and partitioning of genetic variation. Three case histories highlighting long-term ecological genetic research on mule deer Odocoileus hemionus (Rafinesque, 1817), white-tailed deer O. virginianus (Zimmermann, 1780), and Alpine ibex Capra i. ibex Linnaeus, 1758 are presented. Joint examinations of population ecological and genetic data from several populations of each species reveal: (1) that populations are not in genetic equilibrium, but that allele frequencies and heterozygosity change dramatically over time and among cohorts produced in successive years, (2) populations are genetically structured over short and large geographic distances reflecting local breeding structure and patterns of gene flow, respectively; however, this structure is quite dynamic over time, due in part to population exploitation, and (3) restocking programs are often undertaken with small numbers of founding individuals resulting in dramatic declines in levels of genetic variability and increasing levels of genetic differentiation among populations due to genetic drift. Genetic characteristics have and will continue to provide valuable indirect sources of information relating enviromental and human perturbations to changes in population processes.

  9. Distribution and biology of the Blackmouth catshark Galeus melastomus in the Strait of Sicily (Central Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    S. RAGONESE

    2009-05-01

    Full Text Available The Blackmouth catshark, Galeus melastomus, Rafinesque, 1810 (Carcharhiniformes; Scyliorhinidae, is a common, although at present discarded, by- catch of the bottom trawl fisheries in the Strait of Sicily. Given its ecological interest, data gathered in experimental bottom trawl surveys were analysed in order to describe its distribution and main biological traits. The Blackmouth catshark was sampled almost exclusively on the upper slope (200-800, showing the highest frequency of occurrence (69-100%, biomass (BI; 10-85 kg*km-2 and density (DI; 54-506 N*km-2 indexes in the deeper (501-800m grounds. Individual size (total length, TL, mm were between 70-590 and 90-510 in females and males, respectively. The sex ratio (SR was around 0.5. The SR by size showed a gradual decrease till 450 mm class size, followed by an increase up 1 after 500 mm. Virginal/immature specimens represented the bulk of the samples in both females (77% and males (65%; the length at 50% of sexual maturity (Lm50% and corresponding maturity range (Lm25% - Lm75% was 433 (423-443 and 380 (366-394 mm, respectively.

  10. First record of Trichodina heterodentata (Ciliophora: Trichodinidae from channel catfish, Ictalurus punctatus cultivated in Brazil

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    ML. Martins

    Full Text Available This study characterises morphologically Trichodina heterodentata Duncan, 1977 from channel catfish, Ictalurus punctatus (Rafinesque, 1818 in the State of Santa Catarina, Brazil. Body and gill smears were air-dried at room temperature, impregnated with silver nitrate and/or stained with Giemsa. Ten characteristics were selected to compare the present material with other morphological characterisations of T. heterodentata. Prevalence rate was 100%, mean intensity 89,333.70 (3,125 to 299,100 parasites per host. Trichodina heterodentata was considered medium-sized trichodinid with mean body diameter 59.4 ± 8.5 μm, denticulate ring 38.5 ± 4.5 μm, adhesive disc 60.2 ± 6.7 μm diameter and 24.4 ± 1.6 denticles. In relation to previous reports of T. heterodentata this material resembles in 90% of the analysed characters. This work confirms the biometrical variation that exists in the different populations of T. heterodentata. A list of hosts and comparative measurements of T. heterodentata are presented and the channel catfish is considered a new host.

  11. Estimation of jundiá (Rhamdia quelen dietary amino acid requirements based on muscle amino acid composition Estimativa da exigência dietética em aminoácidos para o jundiá (Rhamdia quelen baseada na composição muscular

    Directory of Open Access Journals (Sweden)

    Gustavo Meyer

    2005-08-01

    Full Text Available Jundiá, Rhamdia quelen (Quoy & Gaimard, 1824, is a catfish native to Central and South America. The species has a number of excellent farming features, such as easy handling, low temperature resistance, efficient feed conversion, flavorsome meat and absence of intramuscular bones, and has been increasingly raised in Southern Brazil. However, most of its nutritional requirements have not yet been determined, including the essential amino acid (EAA requirements. The objective of the present study was to estimate such requirements through the determination of muscle tissue amino acid composition for four groups of jundiá. Two groups were wild caught and allocated in two categories: from 1 to 100 g and from 101 to 200 g. The other two groups, obtained from artificial propagation, were differentiated by the diet they had been fed for three months preceding sampling (one diet containing 38% crude protein, CP, and 3,200 kcal kg-1 estimated metabolizable energy, ME, and other with 34% CP and 3,650 kcal kg-1 ME. Similar amino acid compositions were obtained for all groups. An estimate of jundiá daily EAA requirements was made using jundiá muscle tissue composition and also taking into account the average EAA requirement for other omnivorous species such as channel catfish (Ictalurus punctatus, Rafinesque, 1818, Nile tilapia (Oreochromis niloticus, Linnaeus, 1758 and common carp (Cyprinus carpio, Linnaeus, 1758 . The estimated requirements proposed could help formulating diets for jundiá until dietary EAA dose-response experiments are performed.O jundiá, Rhamdia quelen (Quoy & Gaimard, 1824, é um bagre de ampla ocorrência nas Américas do Sul e Central e atualmente vem sendo criado na Região Sul do Brasil por ser uma espécie de fácil manejo, resistente ao frio e eficiente na conversão de alimento, além de apresentar carne saborosa e sem espinhos intramusculares. Apesar disso, muitas das exigências nutricionais desta espécie ainda não foram

  12. Survival and growth of newly transformed Lampsilis cardium and Lampsilis siliquoidea in a flow-through, continuous feeding test system

    Science.gov (United States)

    Meinertz, Jeffery R.; Schreier, Theresa M.; Hess, Karina R.; Bartsch, Michelle

    2011-01-01

    A test system was evaluated for assessing chronic toxicity of waterborne chemicals with early life stage mussels. To determine if the test system could result in ≥80% survival in a control (unexposed) group, fat mucket mussels (Lampsilis siliquoidea Barnes, 1823) and plain pocketbook mussels (L. cardium Rafinesque, 1820) 1 day post transformation were stocked into test chambers (250 mL beakers, water volume, 200 mL, 21 °C, 40 mussels of 1 species per chamber) within a test system constructed for conducting chronic, continuous exposure, flow-through toxicity tests. The test system contained 60 chambers containing silica sand, 30 chambers with L. siliquoidea, and 30 with L. cardium. Each chamber in the continuous feeding system received 1 of 6 food types prepared with concentrated algal products. After 28 days, mussels were harvested from chambers to assess survival and growth. For L. siliquoidea, mean survival ranged from 34 to 80% and mean shell length ranged from 464 to 643 µm. For L. cardium, mean survival ranged from 12 to 66% and mean shell length ranged from 437 to 612 µm. The maximum mean growth rate for L. siliquoidea was 12.7 µm/d and for L. cardium was 11.8 µm/d. When offered a continuous diet of Nannochloropsis, Tetraselmis, and Chlorella for 28 days in the test system, the survival of 1 day post transformation L. siliquoidea was 80%. The test system can be easily enhanced with a pumping system continuously delivering test chemical to the test system's flow stream allowing for chronic toxicity tests with 1 day post transformation mussels.

  13. Effect of tree species and end seal on attractiveness and utility of cut bolts to the redbay ambrosia beetle and granulate ambrosia beetle (coleoptera: Curculionidae: Scolytinae).

    Science.gov (United States)

    Mayfield, A E; Hanula, J L

    2012-04-01

    The redbay ambrosia beetle, Xyleborus glabratus Eichhoff, is a non-native invasive pest and vector of the fungus that causes laurel wilt disease in certain trees of the family Lauraceae. This study assessed the relative attractiveness and suitability of cut bolts of several tree species to X. glabratus. In 2009, female X. glabratus were equally attracted to traps baited with swampbay (Persea palustris (Rafinesque) Sargent) and camphortree (Cinnamomum camphora (L.) J. Presl), which were more attractive than avocado (Persea americana Miller), lancewood (Ocotea coriacea (Swartz) Britton), and sweetbay (Magnolia virginiana L.). These species were more attractive than loblolly bay (Gordonia lasianthus (L.) J. Ellis). X. glabratus entrance hole density and emergence from caged bolts were highest on swampbay and camphortree. In 2010, swampbay was significantly more attractive to X. glabratus than sassafras (Sassafras albidum (Nuttall) Nees), yellow poplar (Liriodendron tulipifera L.), and eastern redbud (Cercis canadensis L.). Sassafras bolts end sealed with a liquid wax-and-water emulsion were more attractive to X. glabratus than end-sealed bolts of yellow poplar and redbud. Relative to unsealed bolts, end seal decreased X. glabratus entrance hole density on swampbay and decreased granulate ambrosia beetle (Xylosandrus crassiusculus (Motschulsky)) trap catch, entrance hole density, and adult emergence from swampbay. X. crassiusculus was not attracted to sassafras, yellow poplar, and redbud and was not more attracted to manuka oil than to unbaited traps. Sassafras was more attractive to X. glabratus than previously reported and supported reproducing populations of the insect. End sealing bolts with a wax-and-water emulsion may not be optimal for attracting and rearing ambrosia beetles in small logs.

  14. Seasonal and interannual effects of hypoxia on fish habitat quality in central Lake Erie

    Science.gov (United States)

    Arend, Kristin K.; Beletsky, Dmitry; DePinto, Joseph; Ludsin, Stuart A.; Roberts, James J.; Rucinski, Daniel K.; Scavia, Donald; Schwab, David J.; Höök, Tomas O.

    2011-01-01

    1. Hypoxia occurs seasonally in many stratified coastal marine and freshwater ecosystems when bottom dissolved oxygen (DO) concentrations are depleted below 2–3 mg O2 L-1. 2. We evaluated the effects of hypoxia on fish habitat quality in the central basin of Lake Erie from 1987 to 2005, using bioenergetic growth rate potential (GRP) as a proxy for habitat quality. We compared the effect of hypoxia on habitat quality of (i) rainbow smelt, Osmerus mordax mordax Mitchill (young-of-year, YOY, and adult), a cold-water planktivore, (ii) emerald shiner, Notropis atherinoides Rafinesque (adult), a warm-water planktivore, (iii) yellow perch, Perca flavescens Mitchill (YOY and adult), a cool-water benthopelagic omnivore and (iv) round goby Neogobius melanostomus Pallas (adult) a eurythermal benthivore. Annual thermal and DO profiles were generated from 1D thermal and DO hydrodynamics models developed for Lake Erie’s central basin. 3. Hypoxia occurred annually, typically from mid-July to mid-October, which spatially and temporally overlaps with otherwise high benthic habitat quality. Hypoxia reduced the habitat quality across fish species and life stages, but the magnitude of the reduction varied both among and within species because of the differences in tolerance to low DO levels and warm-water temperatures. 4. Across years, trends in habitat quality mirrored trends in phosphorus concentration and water column oxygen demand in central Lake Erie. The per cent reduction in habitat quality owing to hypoxia was greatest for adult rainbow smelt and round goby (mean: -35%), followed by adult emerald shiner (mean: -12%), YOY rainbow smelt (mean: -10%) and YOY and adult yellow perch (mean: -8.5%). 5. Our results highlight the importance of differential spatiotemporally interactive effects of DO and temperature on relative fish habitat quality and quantity. These effects have the potential to influence the performance of individual fish species as well as population dynamics

  15. A new species of microphallid (Trematoda: Digenea) infecting a novel host family, the Muraenidae, on the northern Great Barrier Reef, Australia.

    Science.gov (United States)

    Kudlai, Olena; Cribb, Thomas H; Cutmore, Scott C

    2016-11-01

    A new species of microphallid, Longiductotrema tethepae n. sp., is reported from a muraenid eel Gymnothorax pseudothyrsoideus (Bleeker) on the northern Great Barrier Reef. The new species is described based on adults from Gy. pseudothyrsoideus and metacercariae from a grapsid crab, Grapsus albolineatus Latreille in Milbert, collected from off Lizard Island, Queensland, Australia. The new species is assigned to Longiductotrema Deblock & Heard, 1969 based on morphological characters (presence of a cirrus-sac; a long metraterm, intensively ensheathed by gland-cells; an entirely postcaecal uterus; vitellarium composed of two lateral clusters each of about ten follicles, situated in the testicular and post-testicular areas). Longiductotrema tethepae n. sp. is the third species assigned to the genus, differing from its congeners in having a distinctly larger body dimensions, a smaller pharynx in relation to oral sucker, the anterior limits of the vitelline fields at the level of the testes (vs at the level of the ovary) and in its parasitism of a muraenid fish (vs birds). Additionally, the new species differs from L. floridense Deblock & Heard, 1969 in having a shorter metraterm and from L. scandolensis Deblock & Bartoli, 1988 in having a less elongate forebody in relation to body length, shorter caeca and prepharynx, and slightly larger eggs. Phylogenetic analyses, based on partial 28S rRNA gene sequences, showed that the present species is sister to all other microphallids for which sequence data are available. This is the fourth report of a microphallid from a marine eel, the first from the Muraenidae Rafinesque and the first from a marine fish in the Indo-west Pacific. A summary of all species of the Microphallidae parasitising fish is provided.

  16. La pesquería de tiburones oceánicos-costeros en los litorales de Colima, Jalisco y Michoacán

    Directory of Open Access Journals (Sweden)

    Angélica Cruz

    2011-06-01

    Full Text Available La pesquería de tiburón es una de las más importantes en el Pacífico mexicano, en la actualidad no se cuentan con los datos de la composición específica de las capturas de las diferentes flotas. En el presente trabajo se describen aspectos biológicos-pesqueros de las especies de tiburón, capturadas por la flota palangrera de mediana altura del puerto de Manzanillo, en un periodo anual de abril 2006-abril 2007, los muestreos se realizaron mensualmente a bordo de estas embarcaciones. La composición de las capturas estuvo representada por nueve especies (n=1 962, de las cuales Carcharhinus falciformis (Bibron, 1839 (88.12% sostiene esta pesquería y en segundo lugar Prionace glauca (Linnaeus, 1758 (8.21%. Las especies poco frecuentes fueron Sphyrna zygaena (Linnaeus, 1758 con (1.78%, Alopias pelagicus (Nakamura, 1935 (0.82%, Carcharhinus longimanus (Poey, 1861 (0.45%, Alopias superciliosus (Lowe, 1839 (0.35%, Carcharhinus leucas (Valenciennes, 1839 (0.1%, Carcharhinus limbatus (Valenciennes, 1839 (0.1% é Isurus oxyrinchus (Rafinesque, 1810 (0.05%. La fecundidad estimada para C. falciformis fue de 3-7 crías/hembra con tallas de 30-45cm LT; 40.57+2.03cm LT y P. glauca con 5-52 crías/hembra, con tallas de 5-18.6cm LT; 11.61±0.21cm LT. Por lo tanto se asume que C. falciformis presenta un ciclo concurrente y P. glauca probablemente un ciclo bianual consecutivo.

  17. Effects of reproductive condition, roost microclimate, and weather patterns on summer torpor use by a vespertilionid bat

    Science.gov (United States)

    Johnson, Joseph S; Lacki, Michael J

    2014-01-01

    A growing number of mammal species are recognized as heterothermic, capable of maintaining a high-core body temperature or entering a state of metabolic suppression known as torpor. Small mammals can achieve large energetic savings when torpid, but they are also subject to ecological costs. Studying torpor use in an ecological and physiological context can help elucidate relative costs and benefits of torpor to different groups within a population. We measured skin temperatures of 46 adult Rafinesque's big-eared bats (Corynorhinus rafinesquii) to evaluate thermoregulatory strategies of a heterothermic small mammal during the reproductive season. We compared daily average and minimum skin temperatures as well as the frequency, duration, and depth of torpor bouts of sex and reproductive classes of bats inhabiting day-roosts with different thermal characteristics. We evaluated roosts with microclimates colder (caves) and warmer (buildings) than ambient air temperatures, as well as roosts with intermediate conditions (trees and rock crevices). Using Akaike's information criterion (AIC), we found that different statistical models best predicted various characteristics of torpor bouts. While the type of day-roost best predicted the average number of torpor bouts that bats used each day, current weather variables best predicted daily average and minimum skin temperatures of bats, and reproductive condition best predicted average torpor bout depth and the average amount of time spent torpid each day by bats. Finding that different models best explain varying aspects of heterothermy illustrates the importance of torpor to both reproductive and nonreproductive small mammals and emphasizes the multifaceted nature of heterothermy and the need to collect data on numerous heterothermic response variables within an ecophysiological context. PMID:24558571

  18. Incidental spawning of some scombrids in Adriatic or not?

    Directory of Open Access Journals (Sweden)

    Vanja Cikes Kec

    2015-10-01

    Full Text Available During routine monitoring of commercial purse seine catches in 2011, 87 fingerling specimens of scombrids were collected in the southern Adriatic Sea. Sequencing of mitochondrial control region locus inferred that specimens belonged to the Atlantic bluefin tuna, Thunnus thynnus (Linnaeus, 1758 (N=29, bullet tuna, Auxis rochei (Risso, 1810 (N=30 and little tunny, Euthynnus alletteratus, Rafinesque, 1810 (N=28. Due to previously published growth parameters, age of collected specimens was estimated to be approximately 30 days. In order to determine possible location of the spawning event coupled modelling system ROMS-ICHTHYOP was run. Realistic ROMS simulations were made to provide current and density fields for the ICHTHYOP model. ROMS model was forced with realistic surface air-sea fluxes calculated from fine resolution ALADIN model, river inflows, tides and external dynamics. ICHTHYOP was run in the backward mode for 30 days using published investigations on the studied species and its early stage dynamics, such as their growth and developmental stage thermal dependence, lethal temperatures, etc. Apart simulations with coupled modelling system, detailed analysis of prevailing meteorological and oceanographic conditions was made using all available data. Comparison to climatology of the area approved that 2011 had unusually prolonged warm and dry summer season. Occasional inflows of hot and dry air from the northern Africa additionally warm up Adriatic atmosphere. Under these conditions sea surface temperature was up to 2 standard deviations above normal. In the deeper layers, high temperature and salinity were recorded. According to performed simulations it seems that tuna species spawn within the commercial tuna cages (this is not the first evidence of natural spawning within commercial tuna farming facility in the Adriatic, while the other two species most probably opportunistically use positive environmental (abiotic and biotic conditions and

  19. Inhibitory effects of Ponciri Fructus on testosterone-induced benign prostatic hyperplasia in rats.

    Science.gov (United States)

    Jeon, Woo-Young; Kim, Ohn Soon; Seo, Chang-Seob; Jin, Seong Eun; Kim, Jung-Ae; Shin, Hyeun-Kyoo; Kim, Yong-Ung; Lee, Mee-Young

    2017-08-03

    Benign prostatic hyperplasia (BPH) is non-cancerous condition of enlargement of the prostate, a common occurrence in older men. The immature fruits of Poncirus trifoliata (L.) Rafinesque (Rutaceae), Ponciri Fructus are widely used in traditional oriental medicine for the therapy of various diseases. However, little is known about the mechanism underlying the pathogenesis of BPH. In the present study, we investigated the protective effects of a Ponciri Fructus extract (PFE) on the development of BPH in a in a rat model of BPH induced by testosterone propionate (TP). Male Sprague Dawley rats were used as a model of BPH after its induction by daily subcutaneous injections of TP/corn oil, for a period of four weeks. PFE was administrated daily 1 h before TP/corn oil injection by oral gavage at a dose level of 200 mg/kg during the 4 weeks of TP/corn oil injections. All rats were sacrificed at the end of the experiment, we measured the relative prostate weight, the levels of testosterone and dihydrotestosterone (DHT), histological changes, activities of antioxidant enzymes (catalase, glutathione peroxidase, glutathione reductase, and superoxide dismutase), and expression of proliferating cell nuclear antigen (PCNA). In addition, we also measured the inhibition (%) of 5α-reductase in the prostatic tissue. Our findings indicate that PFE significantly inhibited the development of BPH; decreased the relative prostate weight, the level of testosterone and DHT in serum and prostatic tissue, prostatic hyperplasia, expression of PCNA, and increased the antioxidant enzymes. Moreover, PFE showed a weak inhibitory activity on 5α-reductase. These results suggest that PFE may be used as a therapeutic agent for BPH via antiproliferative and antioxidant effects.

  20. MONITORAMENTO DAS PUBLICAÇÕES RELACIONADAS AO CAMARÃO SETE BARBAS Xiphopenaeus kroyeri (Heller, 1862

    Directory of Open Access Journals (Sweden)

    Danilo Francisco Corrêa Lopes

    2013-03-01

    Full Text Available Integrante da ordem Decapoda (Latreille, 1802 subordem Dendrobranchiata (Bate, 1888 e família Penaeidae (Rafinesque, 1815 o camarão sete barbas, Xiphopenaeus kroyeri (Heller, 1862, se distribui no Oceano Pacífico Oriental, desde a cidade de Sinaloa no México até a cidade de Paita no Peru e, no Atlântico Ocidental, desde a Virgínia (Estados Unidos até o Rio Grande do Sul, Brasil. Diversos pesquisadores brasileiros e de outros países vem desenvolvendo trabalhos a respeito da dinâmica populacional, biologia reprodutiva, caracterização da pesca, distribuição espaço-temporal, morfometria, proporção sexual, genética e outras demais áreas de interesse desta espécie.  Monitorar toda produção literária voltada ao Xiphopenaeus kroyeri (Heller, 1862 presente no banco de publicações inseridos no site dos periódicos da CAPES e nas bases do Scopus e da Scientific Electronic Library Online (Scielo, a fim de contabilizar o número de publicações, os principais países que desenvolvem trabalhos, os idiomas, as principais revistas utilizadas pelos autores que desenvolvem pesquisas relacionadas a esta espécie. Espera-se que o desenvolvimento deste trabalho se torne um novo incentivo para os pesquisadores brasileiros, para desenvolver novos estudos direcionados ao camarão sete barbas Xiphopenaeus kroyeri (Heller, 1862.

  1. Acquisition of Borrelia burgdorferi infection by larval Ixodes scapularis (Acari: Ixodidae) associated with engorgement measures

    Science.gov (United States)

    Couret, Janelle; Dyer, M.C.; Mather, T.N.; Han, S.; Tsao, J.I.; LeBrun, R.A.; Ginsberg, Howard

    2017-01-01

    Measuring rates of acquisition of the Lyme disease pathogen, Borrelia burgdorferi sensu lato Johnson, Schmid, Hyde, Steigerwalt & Brenner, by the larval stage of Ixodes scapularis Say is a useful tool for xenodiagnoses of B. burgdorferi in vertebrate hosts. In the nymphal and adult stages of I. scapularis, the duration of attachment to hosts has been shown to predict both body engorgement during blood feeding and the timing of infection with B. burgdorferi. However, these relationships have not been established for the larval stage of I. scapularis. We sought to establish the relationship between body size during engorgement of larval I. scapularis placed on B. burgdorferi-infected, white-footed mice (Peromyscus leucopus Rafinesque) and the presence or absence of infection in larvae sampled from hosts over time. Body size, time, and their interaction were the best predictors of larval infection with B. burgdorferi. We found that infected larvae showed significantly greater engorgement than uninfected larvae as early as 24 h after placement on a host. These findings may suggest that infection with B. burgdorferi affects the larval feeding process. Alternatively, larvae that engorge more rapidly on hosts may acquire infections faster. Knowledge of these relationships can be applied to improve effective xenodiagnosis of B. burgdorferi in white-footed mice. Further, these findings shed light on vector–pathogen–host interactions during an understudied part of the Lyme disease transmission cycle.

  2. Treated municipal sewage discharge affects multiple levels of biological organization in fish.

    Science.gov (United States)

    Porter, Clint M; Janz, David M

    2003-02-01

    The objectives of this study were to examine cellular-, organ-, and organism-level responses in longear sunfish (Lepomis megalotis) and fish community structure in a stream in which treated municipal sewage effluent is discharged and in a nearby reference stream with little surrounding land use. A modified version of the U.S.E.P.A. Rapid Bioassessment Protocol V, which combines a habitat assessment with Karr's index of biotic integrity, was used on 400-m reaches of each stream. The study site had a higher proportion of tolerant species and omnivores and a lower proportion of top predators, suggesting alterations in the fish community and a slight level of water quality impairment. Significant increases in condition factor, hepatosomatic index, serum testosterone, and plasma vitellogenin concentrations were observed in male sunfish collected from the study stream in comparison to fish collected from the reference stream. There were no differences between sites in hepatic expression of the 70-kDa stress protein (HSP70). In conclusion, effects were observed at cellular, organ, organism, and community levels of biological organization in fishes exposed to treated municipal sewage effluent.

  3. Arsenic in freshwater fish in the Chihuahua County water reservoirs (Mexico).

    Science.gov (United States)

    Nevárez, Myrna; Moreno, Myriam Verónica; Sosa, Manuel; Bundschuh, Jochen

    2011-01-01

    Water reservoirs in Chihuahua County, Mexico, are affected by some punctual and non-punctual geogenic and anthropogenic pollution sources; fish are located at the top of the food chain and are good indicators for the ecosystems pollution. The study goal was to: (i) determine arsenic concentration in fish collected from the Chuviscar, Chihuahua, San Marcos and El Rejon water reservoirs; (ii) to assess if the fishes are suitable for human consumption and (iii) link the arsenic contents in fish with those in sediment and water reported in studies made the same year for these water reservoirs. Sampling was done in summer, fall and winter. The highest arsenic concentration in the species varied through the sampling periods: Channel catfish (Ictalurus punctatus) with 0.22 ± 0.15 mg/kg dw in winter and Green sunfish (Lepomis cyanellus) with 2.00 ± 0.15 mg/kg dw in summer in El Rejon water reservoir. A positive correlation of arsenic contents was found through all sampling seasons in fish samples and the samples of sediment and water. The contribution of the weekly intake of inorganic arsenic, based on the consumption of 0.245 kg fish muscles/body weight/week was found lower than the acceptable weekly intake of 0.015 mg/kg/body weight for inorganic arsenic suggested by FAO/WHO.

  4. A pilot study testing a natural and a synthetic Molluscicide for controlling invasive apple snails (Pomacea maculata)

    Science.gov (United States)

    Olivier, Heather M.; Jenkins, Jill A.; Berhow, Mark; Carter, Jacoby

    2016-01-01

    Pomacea maculata (formerly P. insularum), an apple snail native to South America, was discovered in Louisiana in 2008. These snails strip vegetation, reproduce at tremendous rates, and have reduced rice production and caused ecosystem changes in Asia. In this pilot study snails were exposed to two molluscicides, a tea (Camellia sinensis) seed derivative (TSD) or niclosamide monohydrate (Pestanal®, 2′,5-dichloro-4′-nitrosalicylanilide, CAS #73360-56-2). Mortality was recorded after exposure to high or low concentrations (0.03 and 0.015 g/L for TSD, 1.3 and 0.13 mg/L for niclosamide). The TSD induced 100 % mortality at both concentrations. Niclosamide caused 100 % and 17 % mortality at high and low concentrations respectively. These molluscicides were also tested on potential biocontrol agents, the red swamp crayfish (Procambarus clarkii) and redear sunfish (Lepomis microlophus). No crayfish mortalities occurred at either concentration for either chemical, but sunfish experienced 100 % mortality with TSD (0.03 g/L), and 21 % mortality with niclosamide (0.13 mg/L).

  5. Relationship between standard length and preferred water velocity on freshwater fish for naturally diverse river construction methods; Sakana no sumiyasui kawazukuri ni shisuru gyorui no seisoku bunpu to sonoba no ryusoku

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, O. [Ministry of Construction, Tokyo (Japan)

    1998-05-21

    Distribution of Squalidus chankaensis biwae, Lepomis macrochilus LAFINESQUE, Rhinogobius brunneus, Tribolodon hakonensis and Zacoo platypus within the habitat was strongly influenced by in-situ water velocity. For example, larval fish of Squalidus chankaensis biwa, 6-20mm in SL. preferred swimming a water velocity of 0-2cm/sec at the water surface. Similarly. juvenile fish. 30-40mm in SL. preferred a water velocity of 4-5cm/sec. But the preferred water velocity for adult fish ranged from 5-25cm /sec near the bed of the stream. Similarly. adult fish of Zacco platypus was 40-90cm/sec. The other kinds of fish too. it was measured similar phenomenon. Mostly freshwater fish until juvenile period preferred a water velocity of 0-5cm/sec at the water surface near aquatic plants. but in the beginning of adult fish period, preferred water velocity was made great magnification and fish has habitabled at the near bed-pebbles of swift current. These data are important to the design of good fish habitat. 21 refs., 20 figs., 2 tabs.

  6. Assessing the toxicity to fish embryos of surface water from the Watts Bar Lake/Clinch River system

    Energy Technology Data Exchange (ETDEWEB)

    Ivey, L.J.; Niemela, S.L.; McCracken, M.K.; Greeley, M.S. Jr. [Oak Ridge National Lab., TN (United States)

    1995-12-31

    Successful reproduction of fish populations requires the successful development of offspring into new reproductive cohorts. In order to evaluate the ability of fish offspring to survive and develop properly in the Watts Bar Lake/Clinch River system downstream of the Department of Energy facilities in Oak Ridge, TN, a series of fish embryo-larval toxicity tests were conducted on surface water samples from Poplar Creek and the Clinch River adjacent to the Oak Ridge Reservation. Quarterly tests were conducted over an eighteen-month interval with embryos from laboratory stocks of the Japanese medaka (Oryzias latipes). Eggs obtained from largemouth bass (Micropterus salmoides) and redbreast sunfish (Lepomis auritus) collected from reference sites during their respective breeding seasons were fertilized in vitro for additional embryo-larval tests utilizing fish species indigenous to the Watts Bar/Clinch River system. Average survival of medaka embryos decreased significantly in water from Poplar Creek sites within the Oak Ridge Reservation, coincident with an increase in the prevalence of certain developmental abnormalities. Similar but less pronounced results were also obtained with redbreast sunfish embryos. Development of largemouth bass eggs was not adversely affected by any of the tested water samples. These findings suggest that the development of fish eggs and fry in certain reaches of the Watts Bar Lake/Clinch River system may be negatively impacted by activities on the Oak Ridge Reservation.

  7. No evidence of nonlinear effects of predator density, refuge availability, or body size of prey on prey mortality rates.

    Science.gov (United States)

    Simkins, Richard M; Belk, Mark C

    2017-08-01

    Predator density, refuge availability, and body size of prey can all affect the mortality rate of prey. We assume that more predators will lead to an increase in prey mortality rate, but behavioral interactions between predators and prey, and availability of refuge, may lead to nonlinear effects of increased number of predators on prey mortality rates. We tested for nonlinear effects in prey mortality rates in a mesocosm experiment with different size classes of western mosquitofish ( Gambusia affinis ) as the prey, different numbers of green sunfish ( Lepomis cyanellus ) as the predators, and different levels of refuge. Predator number and size class of prey, but not refuge availability, had significant effects on the mortality rate of prey. Change in mortality rate of prey was linear and equal across the range of predator numbers. Each new predator increased the mortality rate by about 10% overall, and mortality rates were higher for smaller size classes. Predator-prey interactions at the individual level may not scale up to create nonlinearity in prey mortality rates with increasing predator density at the population level.

  8. LONG-TERM CHANGES IN MERCURY CONCENTRATIONS IN FISH FROM THE MIDDLE SAVANNAH RIVER

    Energy Technology Data Exchange (ETDEWEB)

    Paller, M; Bill Littrell, B

    2007-01-02

    Total mercury levels were measured in largemouth bass (Micropterus salmoides), ''sunfishes'' (Lepomis spp)., and ''catfish'' (primarily Ameiurus spp.) from 1971 to 2004 in the middle reaches of the Savannah River, which drains the coastal plain of the southeastern U.S. Mercury levels were highest in 1971 but declined over the next ten years due to the mitigation of point sources of industrial pollution. Mercury levels began to increase in the 1980s as a possible consequence of mercury inputs from tributaries and associated wetlands where mercury concentrations were significantly elevated in water and fish. Mercury levels in Savannah River fish decreased sharply in 2001-2003 coincident with a severe drought in the Savannah River basin, but returned to previous levels in 2004 with the resumption of normal precipitation. Regression models showed that mercury levels in Savannah River fish changed significantly over time and were affected by river discharge. Despite temporal changes, there was little overall difference in Savannah River fish tissue mercury levels between 1971 and 2004.

  9. Fish Scale Evidence for Rapid Post Glacial Colonization of an Atlantic Coastal Pond

    Science.gov (United States)

    Daniels, R. A.; Peteet, Dorothy

    1996-01-01

    Fish scales from the sediment of Allamuchy Pond, New Jersey, USA, indicate that fishes were present in the pond within 400 years of the time of the first deposition of organic material, at approximately 12,600 yrs BP. The earliest of the scales, from a white sucker, Catostomus commersoni, appears in sediment dated 12,260 +/- 220 yrs BP. Presence of scales in sediment deposited before I 0,000 yrs BP indicates that Atlantic salmon, Salmo salar, sunfish, Lepomis sp., and yellow perch, Perca flavescens, also were early inhabitants of the pond. The timing of the arrival of each of these fishes suggests that they migrated out from Atlantic coastal refugia. A minnow scale, referred to Phoxininae, was also retrieved; it could not be matched to any cyprinid currently found in northeastern North America. The species present historically in this pond are from five families found currently in ponds throughout the Northeast and sugoest that the lentic palaeo-enviromnent was similar to present mid-elevation or high-latitude lentic systems.

  10. Feeding ecology of Brook Silverside, Golden Shiner, and Subyearling Pumpkinseed in a Lake Ontario embayment

    Science.gov (United States)

    Johnson, James H.; Chalupnicki, Marc; Abbett, Ross; Diaz, Avriel R; Nack, Christopher C

    2017-01-01

    Fish feeding ecology has been shown to vary over a 24-h period in terms of the prey consumed and feeding intensity. Consequently, in order to best determine the interspecific feeding associations within a fish community, examination of the diet at multiple times over a 24-h period is often necessary. We examined the diel feeding ecology of three fish species that were numerically dominant in a Lake Ontario embayment during summer. The diet of each of the three species, young-of-year Pumpkinseed Lepomis gibbosus, Golden Shiner Notemigonus crysoleucas, and Brook Silverside Labidesthes sicculus, was distinct with no significant overlap in diet composition occurring within any of the 4-h time intervals. The diet composition of each species suggested that Brook Silverside were feeding at the surface (terrestrial invertebrates and aquatic surface dwelling hemipterans), whereas young-of-year Pumpkinseed (amphipods) and Golden Shiner (tipulids) were feeding on different benthic prey. Differences in feeding periodicity were most pronounced for young-of-year Pumpkinseed. Our findings provide valuable insights on interspecific feeding associations among these three fish species during summer in a Lake Ontario embayment.

  11. Distribution and abundance of fish populations in the Middle Wabash River

    International Nuclear Information System (INIS)

    Teppen, T.C.; Gammon, J.R.

    1976-01-01

    A field investigation was made of the distribution and abundance of fish within a 161-km portion of the Wabash River to determine effects of heated effluents as well as changes in water quality on ichthyofaunal communities within the river. Twenty-six sampling stations were electrofished, sequentially, four times in 1974 with extended sampling efforts made in the vicinity of two power-generating stations studied since 1967 and 1968. During August an overall rise in river temperature of 4 0 C was observed from upstream to downstream, with several chemical factors also showing slight increases. Although the majority of species populations were influenced either negatively or positively by the gradient of river conditions available to them, the only statistically significant parameters found in the analysis of community structure involved a lower diversity by weight below Terre Haute and a greater abundance of fish above the Cayuga generating station. Decreases occurred downstream in populations of redhorse (Moxostoma sp.), sauger (Stizostedion canadense), longear sunfish (Lepomis megalotis), and gizzard shad (Dorosoma cepedianum), with increases downstream observed in flathead catfish (Pylodictis olivaris), shortnose gar (Lepisosteus platostomus), longnose gar (E. osseus), and bowfin (Amia calva) populations. Carp (Cyprinus carpio) were present in large numbers throughout the study area with a tremendous population increase evident in recent years. Although species associations were variable among the segments, overall community parameters remained relatively unaffected

  12. Competitive Interactions between Invasive Nile Tilapia and Native Fish: The Potential for Altered Trophic Exchange and Modification of Food Webs

    Science.gov (United States)

    Martin, Charles W.; Valentine, Marla M.; Valentine, John F.

    2010-01-01

    Recent studies have highlighted both the positive and negative impacts of species invasions. Most of these studies have been conducted on either immobile invasive plants or sessile fauna found at the base of food webs. Fewer studies have examined the impacts of vagile invasive consumers on native competitors. This is an issue of some importance given the controlling influence that consumers have on lower order plants and animals. Here, we present results of laboratory experiments designed to assess the impacts of unintended aquaculture releases of the Nile tilapia (Oreochromis niloticus), in estuaries of the Gulf of Mexico, on the functionally similar redspotted sunfish (Lepomis miniatus). Laboratory choice tests showed that tilapia prefer the same structured habitat that native sunfish prefer. In subsequent interspecific competition experiments, agonistic tilapia displaced sunfish from their preferred structured habitats. When a piscivore (largemouth bass) was present in the tank with both species, the survival of sunfish decreased. Based on these findings, if left unchecked, we predict that the proliferation of tilapia (and perhaps other aggressive aquaculture fishes) will have important detrimental effects on the structure of native food webs in shallow, structured coastal habitats. While it is likely that the impacts of higher trophic level invasive competitors will vary among species, these results show that consequences of unintended releases of invasive higher order consumers can be important. PMID:21200433

  13. A Pilot Study Testing a Natural and a Synthetic Molluscicide for Controlling Invasive Apple Snails (Pomacea maculata).

    Science.gov (United States)

    Olivier, Heather M; Jenkins, Jill A; Berhow, Mark; Carter, Jacoby

    2016-03-01

    Pomacea maculata (formerly P. insularum), an apple snail native to South America, was discovered in Louisiana in 2008. These snails strip vegetation, reproduce at tremendous rates, and have reduced rice production and caused ecosystem changes in Asia. In this pilot study snails were exposed to two molluscicides, a tea (Camellia sinensis) seed derivative (TSD) or niclosamide monohydrate (Pestanal(®), 2',5-dichloro-4'-nitrosalicylanilide, CAS #73360-56-2). Mortality was recorded after exposure to high or low concentrations (0.03 and 0.015 g/L for TSD, 1.3 and 0.13 mg/L for niclosamide). The TSD induced 100 % mortality at both concentrations. Niclosamide caused 100 % and 17 % mortality at high and low concentrations respectively. These molluscicides were also tested on potential biocontrol agents, the red swamp crayfish (Procambarus clarkii) and redear sunfish (Lepomis microlophus). No crayfish mortalities occurred at either concentration for either chemical, but sunfish experienced 100 % mortality with TSD (0.03 g/L), and 21 % mortality with niclosamide (0.13 mg/L).

  14. Snake (Colubridae: Thamnophis) predatory responses to chemical cues from native and introduced prey species

    Science.gov (United States)

    Mullin, S.J.; Imbert, H.; Fish, J.M.; Ervin, E.L.; Fisher, R.N.

    2004-01-01

    Several aquatic vertebrates have been introduced into freshwater systems in California over the past 100 years. Some populations of the two-striped garter snake (Thamnophis hammondii) have lived in sympatry with these species since their introduction; other populations have never encountered them. To assess the possible adaptation to a novel prey, we tested the predatory responses of T. hammondii from different populations to different chemosensory cues from native and introduced prey species. We presented chemical extracts from potential prey types and 2 control odors to individual snakes on cotton swabs and recorded the number of tongue flicks and attacks directed at each swab. Subject response was higher for prey odors than control substances. Odors from introduced centrarchid fish (Lepomis) elicited higher response levels than other prey types, including native anuran larvae (Pseudacris regilla). The pattern of response was similar for both populations of snakes (experienced and nai??ve, with respect to the introduced prey). We suggest that the generalist aquatic lifestyle of T. hammondii has allowed it to take advantage of increasing populations of introduced prey. Decisions on the management strategies for some of these introduced prey species should include consideration of how T. hammondii populations might respond in areas of sympatry.

  15. Old world versus new world: life-history alterations in a successful invader introduced across Europe.

    Science.gov (United States)

    Fox, Michael G; Copp, Gordon H

    2014-02-01

    We examined differences in pumpkinseed (Lepomis gibbosus) life-history traits between native North American and introduced European populations, and tested three life-history predictions related to the effect of temperature, growth, waterbody size, and the presence/absence of predators on native and non-native populations. Pumpkinseed populations exhibit more 'opportunistic' traits (earlier maturity, smaller size at maturity, and higher reproductive allocation) in their introduced European range than those in their native range. Predictions of life-history traits were improved when indicators of juvenile growth rate (mean length at age 2), waterbody size (surface area), and thermal regime (air temperature degree-days above 10 °C) were incorporated into models along with continental location, but European pumpkinseed populations exhibit more opportunistic life-history traits than North American populations even when these factors are accounted for. Native pumpkinseed in waterbodies containing piscivores mature later and at a larger size, and have lower gonadosomatic indices than those in waterbodies lacking piscivores, whereas there is no significant difference in the same three life-history traits between European waterbodies containing or lacking piscivores. Because congeneric competitors of the pumpkinseed are absent from Europe, the apparent absence of a predator life-history effect there could also be due to the absence of the major sunfish competitors. In either case, the evolution and maintenance of more opportunistic traits in European pumpkinseed can likely be attributed to enemy release, and this may explain the successful establishment and spread of pumpkinseed in many parts of Europe.

  16. Temporal changes in taxonomic and functional diversity of fish assemblages downstream from mountaintop mining

    Science.gov (United States)

    Hitt, Nathaniel P.; Chambers, Douglas B.

    2014-01-01

    Mountaintop mining (MTM) affects chemical, physical, and hydrological properties of receiving streams, but the long-term consequences for fish-assemblage structure and function are poorly understood. We sampled stream fish assemblages using electrofishing techniques in MTM exposure sites and reference sites within the Guyandotte River basin, USA, during 2010–2011. We calculated indices of taxonomic diversity (species richness, abundance, Shannon diversity) and functional diversity (functional richness, functional evenness, functional divergence) to compare exposure and reference assemblages between seasons (spring and autumn) and across years (1999–2011). We based temporal comparisons on 2 sites that were sampled during 1999–2001 by Stauffer and Ferreri (2002). Exposure assemblages had lower taxonomic and functional diversity than reference assemblages or simulated assemblages that accounted for random variation. Differences in taxonomic composition between reference and exposure assemblages were associated with conductivity and aqueous Se concentrations. Exposure assemblages had fewer species, lower abundances, and less biomass than reference assemblages across years and seasons. Green Sunfish (Lepomis cyanellus) and Creek Chub (Semotilus atromaculatus) became numerically dominant in exposure assemblages over time because of their persistence and losses of other taxa. In contrast, species richness increased over time in reference assemblages, a result that may indicate recovery from drought. Mean individual biomass increased as fish density decreased and most obligate invertivores were apparently extirpated at MTM exposure sites. Effects of MTM were not related to physical-habitat conditions but were associated with water-quality variables, which may limit quality and availability of benthic macroinvertebrate prey. Simulations revealed effects of MTM that could not be attributed to random variation in fish assemblage structure.

  17. Long-term trends of native and non-native fish faunas in the American Southwest

    Directory of Open Access Journals (Sweden)

    Olden, J. D.

    2005-06-01

    Full Text Available Environmental degradation and the proliferation of non-native fish species threaten the endemic, and highly unique fish faunas of the American Southwest. The present study examines long-term trends (> 160 years of fish species distributions in the Lower Colorado River Basin and identifies those native species (n = 28 exhibiting the greatest rates of decline and those non-native species (n = 48 exhibiting the highest rates of spread. Among the fastest expanding invaders in the basin are red shiner (Cyprinella lutrensis, fathead minnow (Pimephales promelas, green sunfish (Lepomis cyanellus, largemouth bass (Micropterus salmoides, western mosquitofish (Gambussia affinis and channel catfish (Ictalurus punctatus; species considered to be the most invasive in terms of their negative impacts on native fish communities. Interestingly, non-native species that have been recently introduced (1950+ have generally spread at substantially lower rates as compared to species introduced prior to this time (especially from 1920 to 1950, likely reflecting reductions in human-aided spread of species. We found general agreement between patterns of species decline and extant distribution sizes and official listing status under the U.S. Endangered Species Act. ‘Endangered’ species have generally experienced greater declines and have smaller present-day distributions compared to ‘threatened’ species, which in turn have shown greater declines and smaller distributions than those species not currently listed. A number of notable exceptions did exist, however, and these may provide critical information to help guide the future listing of species (i.e., identification of candidates and the upgrading or downgrading of current listed species that are endemic to the Lower Colorado River Basin. The strong correlation between probability estimates of local extirpation and patterns of native species decline and present-day distributions suggest a possible proactive

  18. Effect of species, life stage, and water temperature on the toxicity of hydrogen peroxide to fish

    Science.gov (United States)

    Rach, J.J.; Schreier, Theresa M.; Howe, G.E.; Redman, S.D.

    1997-01-01

    Hydrogen peroxide is a drug of low regulatory priority status that is effective in treating fish and fish eggs infected by fungi. However, only limited information is available to guide fish culturists in administering hydrogen peroxide to diseased fish. Laboratory tests were conducted to determine (1) the sensitivity of brown trout Salmo trutta, lake trout Salvelinus namaycush, fathead minnow Pimephales promelas, walleye Stizostedion vitreum, channel catfish Ictalurus punctatus, and bluegill Lepomis, machrochirus to hydrogen peroxide treatments; (2) the sensitivity of various life stages of rainbow trout Oncorhynchus mykiss to hydrogen peroxide treatments; and (3) the effect of water temperature on the acute toxicity of hydrogen peroxide to three fish species. Fish were exposed to hydrogen peroxide concentrations ranging from 100 to 5,000 mu L/L (ppm) for 15-min or 45-min treatments every other day for four consecutive treatments to determine the sensitivity of various species and life stages of fish. Except for walleye, most species of fish tested (less than or equal to 2 g) tolerated hydrogen peroxide of 1,000 mu L/L or greater. Walleyes were sensitive to hydrogen peroxide concentrations as low as 100 mu L/L. A correlation was found between the toxicity of hydrogen peroxide and the life stages of rainbow trout; larger fish were more sensitive. Generally, the toxicity of hydrogen peroxide increased for all species as water temperature increased. The results of these experiments demonstrate that it is important to consider the effects of species, life stage, and water temperature when conducting hydrogen peroxide treatments.

  19. Relationships among catch, angler catisfaction, and fish assemblage characteristics of an urban small impoundment fishery

    Science.gov (United States)

    Ivasauskas, Tomas J.; Xiong, Wilson N.; Engman, Augustin C.; Fischer, Jesse R.; Kwak, Thomas J.; Rundle, Kirk R.

    2017-01-01

    Urban fisheries provide unique angling opportunities for people from traditionally underrepresented demographics. Lake Raleigh is a 38-ha impoundment located on the North Carolina State University campus in Raleigh. Like many urban fisheries, little is known about angler use and satisfaction or how angling catch rate is related to fish availability in Lake Raleigh. We characterized the recreational fishery and fish assemblage with concurrent creel and boat electrofishing surveys over the course of one year. In total, 245 anglers were interviewed on 68 survey days. On average, anglers spent 1.7 h fishing per trip and caught 0.385 fish h –1. A large proportion of anglers (43.9%) targeted multiple species, whereas 36.5% targeted largemouth bass (Micropterus salmoides), 10.0% targeted panfish (i.e., sunfishes [Lepomis spp.] and crappies [Pomoxis spp.]), and 9.6% targeted catfish (Ameiurus spp. and Ictalurus spp.). Most anglers (69.4%) were satisfied with their experience, and overall satisfaction was unrelated to catch rate. Pulsed-DC boat electrofishing was conducted on 25 dates, and 617 fish were sampled. Angler catch rate was unrelated to electrofishing catch rate, implying that anglers' catch rate was independent of fish density or availability. Our results demonstrate that even minimally managed urban fisheries can provide high angler satisfaction, with limited dedication of management resources. Relationships Among Catch, Angler Satisfaction, and Fish Assemblage Characteristics of an Urban Small Impoundment Fishery (PDF Download Available). Available from: https://www.researchgate.net/publication/316636550_Relationships_Among_Catch_Angler_Satisfaction_and_Fish_Assemblage_Characteristics_of_an_Urban_Small_Impoundment_Fishery [accessed Aug 11, 2017].

  20. Using data from an encounter sampler to model fish dispersal

    Science.gov (United States)

    Obaza, A.; DeAngelis, D.L.; Trexler, J.C.

    2011-01-01

    A method to estimate speed of free-ranging fishes using a passive sampling device is described and illustrated with data from the Everglades, U.S.A. Catch per unit effort (CPUE) from minnow traps embedded in drift fences was treated as an encounter rate and used to estimate speed, when combined with an independent estimate of density obtained by use of throw traps that enclose 1 m2 of marsh habitat. Underwater video was used to evaluate capture efficiency and species-specific bias of minnow traps and two sampling studies were used to estimate trap saturation and diel-movement patterns; these results were used to optimize sampling and derive correction factors to adjust species-specific encounter rates for bias and capture efficiency. Sailfin mollies Poecilia latipinna displayed a high frequency of escape from traps, whereas eastern mosquitofish Gambusia holbrooki were most likely to avoid a trap once they encountered it; dollar sunfish Lepomis marginatus were least likely to avoid the trap once they encountered it or to escape once they were captured. Length of sampling and time of day affected CPUE; fishes generally had a very low retention rate over a 24 h sample time and only the Everglades pygmy sunfish Elassoma evergladei were commonly captured at night. Dispersal speed of fishes in the Florida Everglades, U.S.A., was shown to vary seasonally and among species, ranging from 0.05 to 0.15 m s-1 for small poeciliids and fundulids to 0.1 to 1.8 m s-1 for L. marginatus. Speed was generally highest late in the wet season and lowest in the dry season, possibly tied to dispersal behaviours linked to finding and remaining in dry-season refuges. These speed estimates can be used to estimate the diffusive movement rate, which is commonly employed in spatial ecological models.

  1. Effects of depletion sampling by standard three-pass pulsed DC electrofishing on blood chemistry parameters of fishes from Appalachian streams

    Science.gov (United States)

    Densmore, Christine L.; Panek, Frank M.

    2013-01-01

    Adverse effects on fishes captured by electrofishing techniques have long been recognized, although the extent of associated physical injury and behavioral alterations are highly variable and dependent on a number of factors. We examined the effects of three-pass pulsed DC (PDC) electrofishing on two salmonid species (Rainbow Trout Oncorhynchus mykiss and Brook Trout Salvelinus fontinalis) and five other genera (Green Sunfish Lepomis cyanellus, Potomac Sculpin Cottus girardi, Fathead Minnow Pimephales promelas, Largemouth Bass Micropterus salmoides, and Channel Catfish Ictalurus punctatus) common to Appalachian streams. We examined the corresponding effects of PDC electroshock on the following physiological indicators of stress and trauma: blood glucose and serum lactate, as well as on other blood chemistry, namely, enzymes, electrolytes, minerals, and proteins. All species demonstrated physiological responses to PDC electroshock, indicated by the biochemical differences in blood parameters in unshocked and shocked groups of fish with or without gross evidence of hemorrhagic trauma. Serum lactate was the most consistent indicator of these effects. Significant differences in whole blood glucose levels were also noted in treatment groups in all species except Green Sunfish, although the patterns observed were not as consistent as for serum lactate. Elevations in the serum enzymes, aspartate aminotransferase and creatine kinase, in the electroshocked fish occurred only in the two salmonid species. In many instances, although blood parameters were elevated in electroshocked fish compared with the unshocked controls for a given species, there were no differences in those levels in electroshocked fish based on the presence of gross hemorrhagic trauma to axial musculature. While some of the blood parameters examined correlated with both the occurrence of electroshock and the resultant tissue injury, there was no apparent link between the altered blood chemistry and

  2. Contaminants of emerging concern in tributaries to the Laurentian Great Lakes: II. Biological consequences of exposure

    Science.gov (United States)

    Brigham, Mark E.; Choy, Steven J.; Moore, Jeremy N.; Banda, Jo A.; Gefell, Daniel J.; Minarik, Thomas A.

    2017-01-01

    The Laurentian Great Lakes contain one fifth of the world’s surface freshwater and have been impacted by human activity since the Industrial Revolution. In addition to legacy contaminants, nitrification and invasive species, this aquatic ecosystem is also the recipient of Contaminants of Emerging Concern (CECs) with poorly understood biological consequences. In the current study, we documented the presence, concentrations, and biological effects of CECs across 27 field sites in six Great Lakes tributaries by examining over 2250 resident and caged sunfish (Lepomis ssp.) for a variety of morphological and physiological endpoints and related these results to CEC occurrence. CEC were ubiquitous across studies sites and their presence and concentrations in water and sediment were highest in effluent dominated rivers and downstream of municipal wastewater treatment plant discharges. However, even putative upstream reference sites were not free of CEC presence and fish at these sites exhibited biological effects consistent with CEC exposure. Only the Fox River exhibited consistent adverse biological effects, including increased relative liver size, greater prominence of hepatocyte vacuoles and increased plasma glucose concentrations. Canonical Redundancy Analysis revealed consistent patterns of biological consequences of CEC exposure across all six tributaries. Increasing plasma glucose concentrations, likely as a result of pollutant-induced metabolic stress, were associated with increased relative liver size and greater prominence of hepatocyte vacuoles. These indicators of pollutant exposure were inversely correlated with indicators of reproductive potential including smaller gonad size and less mature gametes. The current study highlights the need for greater integration of chemical and biological studies and suggests that CECs in the Laurentian Great Lakes Basin may adversely affect the reproductive potential of exposed fish populations. PMID:28953953

  3. Predation on exotic zebra mussels by native fishes: Effects on predator and prey

    Science.gov (United States)

    Magoulick, D.D.; Lewis, L.C.

    2002-01-01

    1. Exotic zebra mussels, Dreissena polymorpha, occur in southern U.S. waterways in high densities, but little is known about the interaction between native fish predators and zebra mussels. Previous studies have suggested that exotic zebra mussels are low profitability prey items and native vertebrate predators are unlikely to reduce zebra mussel densities. We tested these hypotheses by observing prey use of fishes, determining energy content of primary prey species of fishes, and conducting predator exclusion experiments in Lake Dardanelle, Arkansas. 2. Zebra mussels were the primary prey eaten by 52.9% of blue catfish, Ictalurus furcatus; 48.2% of freshwater drum, Aplodinotus grunniens; and 100% of adult redear sunfish, Lepomis microlophus. Blue catfish showed distinct seasonal prey shifts, feeding on zebra mussels in summer and shad, Dorosoma spp., during winter. Energy content (joules g-1) of blue catfish prey (threadfin shad, Dorosoma petenense; gizzard shad, D. cepedianum; zebra mussels; and asiatic clams, Corbicula fluminea) showed a significant species by season interaction, but shad were always significantly greater in energy content than bivalves examined as either ash-free dry mass or whole organism dry mass. Fish predators significantly reduced densities of large zebra mussels (>5 mm length) colonising clay tiles in the summers of 1997 and 1998, but predation effects on small zebra mussels (???5 mm length) were less clear. 3. Freshwater drum and redear sunfish process bivalve prey by crushing shells and obtain low amounts of higher-energy food (only the flesh), whereas blue catfish lack a shell-crushing apparatus and ingest large amounts of low-energy food per unit time (bivalves with their shells). Blue catfish appeared to select the abundant zebra mussel over the more energetically rich shad during summer, then shifted to shad during winter when shad experienced temperature-dependent stress and mortality. Native fish predators can suppress adult zebra

  4. Contaminants of emerging concern in tributaries to the Laurentian Great Lakes: II. Biological consequences of exposure

    Science.gov (United States)

    Thomas, Linnea M.; Jorgenson, Zachary G.; Brigham, Mark E.; Choy, Steven J.; Moore, Jeremy N.; Banda, Jo A.; Gefell, D.J.; Minarik, Thomas A.; Schoenfuss, Heiko L.

    2017-01-01

    The Laurentian Great Lakes contain one fifth of the world’s surface freshwater and have been impacted by human activity since the Industrial Revolution. In addition to legacy contaminants, nitrification and invasive species, this aquatic ecosystem is also the recipient of Contaminants of Emerging Concern (CECs) with poorly understood biological consequences. In the current study, we documented the presence, concentrations, and biological effects of CECs across 27 field sites in six Great Lakes tributaries by examining over 2250 resident and caged sunfish (Lepomis ssp.) for a variety of morphological and physiological endpoints and related these results to CEC occurrence. CEC were ubiquitous across studies sites and their presence and concentrations in water and sediment were highest in effluent dominated rivers and downstream of municipal wastewater treatment plant discharges. However, even putative upstream reference sites were not free of CEC presence and fish at these sites exhibited biological effects consistent with CEC exposure. Only the Fox River exhibited consistent adverse biological effects, including increased relative liver size, greater prominence of hepatocyte vacuoles and increased plasma glucose concentrations. Canonical Redundancy Analysis revealed consistent patterns of biological consequences of CEC exposure across all six tributaries. Increasing plasma glucose concentrations, likely as a result of pollutant-induced metabolic stress, were associated with increased relative liver size and greater prominence of hepatocyte vacuoles. These indicators of pollutant exposure were inversely correlated with indicators of reproductive potential including smaller gonad size and less mature gametes. The current study highlights the need for greater integration of chemical and biological studies and suggests that CECs in the Laurentian Great Lakes Basin may adversely affect the reproductive potential of exposed fish populations.

  5. Saturated Branched Chain, Normal Odd-Carbon-Numbered, and n-3 (Omega-3) Polyunsaturated Fatty Acids in Freshwater Fish in the Northeastern United States.

    Science.gov (United States)

    Wang, Dong Hao; Jackson, James R; Twining, Cornelia; Rudstam, Lars G; Zollweg-Horan, Emily; Kraft, Clifford; Lawrence, Peter; Kothapalli, Kumar; Wang, Zhen; Brenna, J Thomas

    2016-10-04

    The fatty acid profiles of wild freshwater fish are poorly characterized as a human food source for several classes of fatty acids, particularly for branched chain fatty acids (BCFA), a major bioactive dietary component known to enter the US food supply primarily via dairy and beef fat. We evaluated the fatty acid content of 27 freshwater fish species captured in the northeastern US with emphasis on the BCFA and bioactive polyunsaturated fatty acids (PUFA) most associated with fish, specifically n-3 (omega-3) eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Mean BCFA content across all species was 1.0 ± 0.5% (mean ± SD) of total fatty acids in edible muscle, with rainbow smelt (Osmerus mordax) and pumpkinseed (Lepomis gibbosus) the highest at >2% BCFA. In comparison, EPA + DHA constituted 28% ± 7% of total fatty acids. Across all fish species, the major BCFA were iso-15:0, anteiso-15:0, iso-16:0, iso-17:0 and anteiso-17:0. Fish skin had significantly higher BCFA content than muscle tissues, at 1.8% ± 0.7%, but lower EPA and DHA. Total BCFA in fish skins was positively related with that in muscle (r 2 = 0.6). The straight chain saturates n-15:0 and n-17:0 which have been identified previously as markers for dairy consumption were relatively high with means of 0.4% and 0.6%, respectively, and may be an underappreciated marker for seafood intake. Consuming a standardized portion, 70 g (2.5 oz), of wild freshwater fish contributes only small amounts of BCFA, 2.5-24.2 mg, to the American diet, while it adds surprisingly high amounts of EPA + DHA (107 mg to 558 mg).

  6. Evolution and Cryo-electron Microscopy Capsid Structure of a North American Bat Adenovirus and Its Relationship to Other Mastadenoviruses

    Science.gov (United States)

    Hackenbrack, Nicole; Rogers, Matthew B.; Ashley, Robert E.; Keel, M. Kevin; Kubiski, Steven V.; Bryan, John A.; Ghedin, Elodie; Holmes, Edward C.; Hafenstein, Susan L.

    2016-01-01

    ABSTRACT Since the first description of adenoviruses in bats in 2006, a number of micro- and megabat species in Europe, Africa, and Asia have been shown to carry a wide diversity of adenoviruses. Here, we report on the evolutionary, biological, and structural characterization of a novel bat adenovirus (BtAdV) recovered from a Rafinesque's big-eared bat (Corynorhinus rafinesquii) in Kentucky, USA, which is the first adenovirus isolated from North American bats. This virus (BtAdV 250-A) exhibits a close phylogenetic relationship with Canine mastadenovirus A (CAdV A), as previously observed with other BtAdVs. To further investigate the relationships between BtAdVs and CAdVs, we conducted mass spectrometric analysis and single-particle cryo-electron microscopy reconstructions of the BtAdV 250-A capsid and also analyzed the in vitro host ranges of both viruses. Our results demonstrate that BtAdV 250-A represents a new mastadenovirus species that, in contrast to CAdV, has a unique capsid morphology that contains more prominent extensions of protein IX and can replicate efficiently in a phylogenetically diverse range of species. These findings, in addition to the recognition that both the genetic diversity of BtAdVs and the number of different bat species from disparate geographic regions infected with BtAdVs appears to be extensive, tentatively suggest that bats may have served as a potential reservoir for the cross-species transfer of adenoviruses to other hosts, as theorized for CAdV. IMPORTANCE Although many adenoviruses are host specific and likely codiverged with their hosts over millions of years, other adenoviruses appear to have emerged through successful cross-species transmission events on more recent time scales. The wide geographic distribution and genetic diversity of adenoviruses in bats and their close phylogenetic relationship to Canine mastadenovirus A (CAdV A) has raised important questions about how CAdV A, and possibly other mammalian adenoviruses

  7. Densidade e tamanho populacional de mamíferos cinegéticos em duas Unidades de Conservação do Estado do Rio de Janeiro, Brasil Density and population size of game mammals in two Conservation Units of the State of Rio de Janeiro, Brazil

    Directory of Open Access Journals (Sweden)

    Roberta M. de Araújo

    2008-09-01

    Full Text Available A Mata Atlântica, apesar de ainda sofrer uma intensa devastação, abriga 261 espécies de mamíferos, sendo 73 endêmicos. Mamíferos de grande porte estão entre os mais vulneráveis à caça, perda de habitat e tráfico de animais. No Estado do Rio de Janeiro existem somente duas Reservas Biológicas de Mata Atlântica de baixada, a Reserva Biológica de Poço das Antas e a Reserva Biológica União. O presente estudo teve como objetivo avaliar a influência da prática da caça ilegal sobre a fauna de mamíferos nestas duas Unidades de Conservação. O levantamento populacional foi realizado utilizando o método de transecção linear e 375 quilômetros foram percorridos durante o período de dezembro de 2003 a janeiro de 2005. Os dados de estimativa de densidade populacional foram analisados no programa DISTANCE 5.0. Através de encontros visuais foram confirmadas 12 espécies durante o levantamento, sendo estas regularmente caçadas na região. As espécies que apresentaram maior densidade nas duas Unidades de Conservação foram o macaco-prego (Cebus nigritus Erxleben, 1777, o bugio (Alouatta guariba Lacépède, 1799, tatu-galinha (Dasypus novemcintus Linnaeus, 1758 e o tatu (Dasypus septemcinctus Linnaeus, 1758. As espécies mais raras ou ausentes foram a anta (Tapirus terrestris Brünnich, 1771, o veado (Mazama americana Rafinesque, 1817 e o queixada (Tayassu pecari Link, 1795. Evidências diretas e indiretas da ação da caça ilegal foram observadas nas duas áreas de estudo, indicando que a caça é uma prática comum nessas Reservas Biológicas. A sobrevivência a longo prazo dessas espécies é questionável, já que as populações remanescentes em fragmentos são pequenas e isoladas, o que as tornam muito susceptível à extinção mesmo sob uma baixa pressão de caça.The Atlantic Rain Forest even though suffering intense devastation, shelters 261 species of mammals, 73 endemic. Large mammals were among the most vulnerable to

  8. Influence of metal(loid) bioaccumulation and maternal transfer on embryo-larval development in fish exposed to a major coal ash spill.

    Science.gov (United States)

    Greeley, Mark S; Adams, S Marshall; Elmore, Logan R; McCracken, Mary K

    2016-04-01

    In December 2008, an earthen retaining wall at the Tennessee Valley Authority (TVA) Kingston Fossil Fuel Plant failed and released 4.1 millionm(3) of coal ash to rivers flowing into Watts Bar Reservoir in east Tennessee, United States (U.S.). As part of a comprehensive effort to evaluate the risks to aquatic resources from this spill - the largest in U.S. history - we compared bioaccumulation and maternal transfer of selenium (Se), arsenic (As), and mercury (Hg) in adult redear sunfish (Lepomis macrolophus), collected two years after the spill from both coal-ash exposed and non-exposed areas of the Emory and Clinch Rivers, with the success of embryo-larval development in their offspring. Whole body and ovary concentrations of Se in female sunfish at three study sites downstream of the spill were significantly elevated (site means=4.9-5.3 and 6.7-9.0mg/kg d.w. whole body and ovary concentrations, respectively) compared with concentrations in fish from reference sites upstream of the spill site (2.2-3.2mg/kg d.w. for whole bodies and 3.6-4.8mg/kg d.w. for ovaries). However, Se concentrations in coal ash-exposed areas remain below proposed U.S. Environmental Protection Agency (USEPA) criteria for the protection of aquatic life. Site-to-site variation in fish concentrations of As and Hg were not well-correlated with ash-exposure, reflecting the multiple sources of these metal(loid)s in the affected watersheds. In 7-day laboratory tests of embryos and larvae derived from in vitro crosses of eggs and sperm from these field-collected sunfish, fertilization success, hatching success, embryo-larval survival, and incidences of developmental abnormalities did not differ significantly between ash-exposed and non-exposed fish. Furthermore, these developmental endpoints were not correlated with whole body or ovary concentrations of Se, As, or Hg in the maternal fish, or with fish size, ovary weight, or gonadal-somatic indices. Results from this and related studies associated

  9. An Assessment of the Bioaccumulation of PCBs and Chloridane Near the U.S. Department of Energy's Kansas City Plant

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, M.J.

    2003-12-30

    important component of this effort, the fish sampling locations and species collected were essentially the same as in previous studies. In general, locations were chosen upstream and downstream of major KCP outfalls to help evaluate the importance of those outfalls as sources of PCBs. Green sunfish (Lepomis cyanellus) and channel catfish (Ictalurus punctatus) were again the primary species collected.

  10. Potential Human Health Risk by Metal(loid)s, 234,238U and 210Po due to Consumption of Fish from the “Luis L. Leon” Reservoir (Northern México)

    Science.gov (United States)

    Luna-Porres, Mayra Y.; Rodríguez-Villa, Marco A.; Herrera-Peraza, Eduardo F.; Renteria-Villalobos, Marusia; Montero-Cabrera, María E.

    2014-01-01

    Concentrations of As, Cu, Fe, Hg, Pb and Zn and activity concentrations from 234,238U and 210Po in water, fillet, liver and gills were determined in three stocked fish species from the Luis L. Leon reservoir, located in Northern Mexico. The considered species were Lepomis cyanellus, Cyprinus carpio and Ictalurus furcatus. 238U and 234U activity concentration (AC) in fillet samples showed values of 0.007–0.014 and 0.01–0.02 Bq∙kg−1 wet weight (ww), respectively. Liver samples for L. cyanellus, C. carpio and I. furcatus present 210Po AC of 1.16–3.26, 0.70–1.13 and 0.93–1.37 Bq∙kg−1 ww. Arsenic, mercury and lead concentration intervals in fillet samples were 0.13–0.39, 0.005–0.126 and 0.009–0.08 mg∙kg−1 ww, respectively, while in gill samples they were 0.11–0.43, 0.002–0.039 and 0.02–0.26 mg∙kg−1 ww. The elemental Bioaccumulation Factor (BAF) for fish tissues with respect to their concentrations in water was determined. L. cyanellus showed the highest BAF values for As and total U, being BAFAs = 37 and 40 L∙kg−1 in fillet and gills, respectively, and BAFU total = 1.5 L∙kg−1 in fillet. I. furcatus showed the highest BAF values for Hg and Pb, being BAFHg = 40 and 13 L∙kg−1 in fillet and gills, and BAFPb = 6.5 and 22 L∙kg−1 in fillet and gills, respectively. Some metal(loid) concentrations are slightly higher than European regulations for fish fillets. The difference in concentrations of metal(loid)s in fillet among the studied species is probably due to their differences in diet and habitat. PMID:24968208

  11. Potential Human Health Risk by Metal(loids, 234,238U and 210Po due to Consumption of Fish from the “Luis L. Leon” Reservoir (Northern México

    Directory of Open Access Journals (Sweden)

    Mayra Y. Luna-Porres

    2014-06-01

    Full Text Available Concentrations of As, Cu, Fe, Hg, Pb and Zn and activity concentrations from 234,238U and 210Po in water, fillet, liver and gills were determined in three stocked fish species from the Luis L. Leon reservoir, located in Northern Mexico. The considered species were Lepomis cyanellus, Cyprinus carpio and Ictalurus furcatus. 238U and 234U activity concentration (AC in fillet samples showed values of 0.007–0.014 and 0.01–0.02 Bq∙kg−1 wet weight (ww, respectively. Liver samples for L. cyanellus, C. carpio and I. furcatus present 210Po AC of 1.16–3.26, 0.70–1.13 and 0.93–1.37 Bq∙kg−1 ww. Arsenic, mercury and lead concentration intervals in fillet samples were 0.13–0.39, 0.005–0.126 and 0.009–0.08 mg∙kg−1 ww, respectively, while in gill samples they were 0.11–0.43, 0.002–0.039 and 0.02–0.26 mg∙kg−1 ww. The elemental Bioaccumulation Factor (BAF for fish tissues with respect to their concentrations in water was determined. L. cyanellus showed the highest BAF values for As and total U, being BAFAs = 37 and 40 L∙kg−1 in fillet and gills, respectively, and BAFU total = 1.5 L∙kg−1 in fillet. I. furcatus showed the highest BAF values for Hg and Pb, being BAFHg = 40 and 13 L∙kg−1 in fillet and gills, and BAFPb = 6.5 and 22 L∙kg−1 in fillet and gills, respectively. Some metal(loid concentrations are slightly higher than European regulations for fish fillets. The difference in concentrations of metal(loids in fillet among the studied species is probably due to their differences in diet and habitat.

  12. Family-Group Names In Coleoptera (Insecta

    Directory of Open Access Journals (Sweden)

    Patrice Bouchard

    2011-04-01

    . protectum over Stereolidae Rafinesque, 18

  13. La pesquería de tiburones oceánicos-costeros en los litorales de Colima, Jalisco y Michoacán

    Directory of Open Access Journals (Sweden)

    Angélica Cruz

    2011-06-01

    Full Text Available La pesquería de tiburón es una de las más importantes en el Pacífico mexicano, en la actualidad no se cuentan con los datos de la composición específica de las capturas de las diferentes flotas. En el presente trabajo se describen aspectos biológicos-pesqueros de las especies de tiburón, capturadas por la flota palangrera de mediana altura del puerto de Manzanillo, en un periodo anual de abril 2006-abril 2007, los muestreos se realizaron mensualmente a bordo de estas embarcaciones. La composición de las capturas estuvo representada por nueve especies (n=1 962, de las cuales Carcharhinus falciformis (Bibron, 1839 (88.12% sostiene esta pesquería y en segundo lugar Prionace glauca (Linnaeus, 1758 (8.21%. Las especies poco frecuentes fueron Sphyrna zygaena (Linnaeus, 1758 con (1.78%, Alopias pelagicus (Nakamura, 1935 (0.82%, Carcharhinus longimanus (Poey, 1861 (0.45%, Alopias superciliosus (Lowe, 1839 (0.35%, Carcharhinus leucas (Valenciennes, 1839 (0.1%, Carcharhinus limbatus (Valenciennes, 1839 (0.1% é Isurus oxyrinchus (Rafinesque, 1810 (0.05%. La fecundidad estimada para C. falciformis fue de 3-7 crías/hembra con tallas de 30-45cm LT; 40.57+2.03cm LT y P. glauca con 5-52 crías/hembra, con tallas de 5-18.6cm LT; 11.61±0.21cm LT. Por lo tanto se asume que C. falciformis presenta un ciclo concurrente y P. glauca probablemente un ciclo bianual consecutivo.Fishery of oceanic and coastal sharks in Colima, Jalisco and Michoacán. Shark fishery is one of the most important activities in the Mexican Pacific coast, nevertheless, there is few data available about the specific captures done by the fleet along the coast. This study describes fishery biology aspects of the shark species catched by the semi-industrial long-line fleet of Manzanillo. Monthly samplings were made on board of these vessels during an annual period from April 2006 to April 2007. Captured species composition (n=1 962 organisms was represented by nine species. The one

  14. Family-group names in Coleoptera (Insecta)

    Science.gov (United States)

    Bouchard, Patrice; Bousquet, Yves; Davies, Anthony E.; Alonso-Zarazaga, Miguel A.; Lawrence, John F.; Lyal, Chris H. C.; Newton, Alfred F.; Reid, Chris A. M.; Schmitt, Michael; Ślipiński, S. Adam; Smith, Andrew B. T.

    2011-01-01

    nom. oblitum (Tenebrionidae), Throscidae Laporte, 1840 nom. protectum over Stereolidae Rafinesque, 1815 nom. oblitum (Throscidae) and Lophocaterini Crowson, 1964 over Lycoptini Casey, 1890 nom. oblitum (Trogossitidae); Monotoma Herbst, 1799 nom. protectum over Monotoma Panzer, 1792 nom. oblitum (Monotomidae); Pediacus Shuckard, 1839 nom. protectum over Biophloeus Dejean, 1835 nom. oblitum (Cucujidae), Pachypus Dejean, 1821 nom. protectum over Pachypus Billberg, 1820 nom. oblitum (Scarabaeidae), Sparrmannia Laporte, 1840 nom. protectum over Leocaeta Dejean, 1833 nom. oblitum and Cephalotrichia Hope, 1837 nom. oblitum (Scarabaeidae). PMID:21594053

  15. Bioaccumulation Studies Associated with the Kingston Fly Ash Spill, Spring 2009 - Fall 2010

    Energy Technology Data Exchange (ETDEWEB)

    Adams, Marshall [ORNL; Brandt, Craig C [ORNL; Fortner, Allison M [ORNL

    2012-05-01

    four seasonal collections: Spring 2009, Fall 2009, Spring 2010, and Fall 2010. Both the Spring and Fall studies have focused on 3-4 sentinel fish species that represent different feeding habits, behaviors, and home ranges. In addition to bioaccumulation studies, the Spring investigations also included evaluation of fish health and reproductive integrity on the same fish used for bioaccumulation. Two associated reports present the fish health (Adams et al 2012) and reproductive studies (Greeley et al 2012) conducted in 2009 and 2010. The fish health study conducted in conjunction with the bioaccumulation and reproductive study is critical for assessing and evaluating possible causal relationships between contaminant exposure (bioaccumulation) and the response of fish to exposure as reflected by the various measurements of fish health. This report emphasizes evaluation of arsenic and selenium bioaccumulation in fish and consists of four related studies (Sections 2-5) including, (1) bioaccumulation in liver and ovaries, (2) bioaccumulation in whole body gizzard shad (Dorosoma cepedianum), (3) bioaccumulation in muscle tissue or fillets, and (4) a reconstruction analysis which establishes the relationship between selenium in muscle tissue and that of the whole body of bluegill (Lepomis machrochirus). Metals other than arsenic and selenium are evaluated separately in Section 6. This report focuses on selenium and arsenic for the following reasons: (1) based on baseline studies conducted in early 2009 in the Emory and Clinch River, only two potentially fly-ash related metals, selenium and arsenic, appeared to be elevated above background or reference levels, (2) selenium and arsenic are two of the metals in coal ash that are known to bioaccumulate and cause toxicity in wildlife, and (3) based on bioaccumulation studies of bluegill and carp (Cyprinus carpio) in the Stilling Pond during Spring 2009, which would represent a worst case situation for metal bioaccumulation