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Sample records for bluegill lepomis macrochirus

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

    Energy Technology Data Exchange (ETDEWEB)

    Belk, M.C. [Georgia Univ., Athens, GA (United States)

    1992-12-31

    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.

  2. Recruitment of helminth parasites by bluegills (Lepomis macrochirus) using a modified live-box technique

    Energy Technology Data Exchange (ETDEWEB)

    Esch, G.W. (Wake Forest Univ., Winston-Salem, NC); Campbell, G.C.; Conners, R.E.; Coggins, J.R.

    1976-05-01

    A modification of the live-box technique was used in studying the recruitment of helminth parasites by bluegills, Lepomis macrochirus, during the summer of 1973--1974 in Gull Lake, Kalamazoo County, Michigan. Simultaneously, an approximately even number of L. macrochirus were captued by hook and line and the parasite fauna compared with that of tethered bluegills. The results show that the nature of the parasite faunas in the two groups of fish is similar. Results of tether experiments indicate that the acanthocephalan, Pomphorhynchus bulbocolli, was recruited at a higher rate early in the summer, then declined while Leptorhynchoides thecatus was initially recruited slowly, then increased in rate as P. bulbocolli was declining. The spatial distribution of L. thecatus indicated a preference for the ceca and anterior two-thirds of the intestine while P. bulbocolli localized most frequently in the anterior two-thirds of the intestine. While there was a zone of overlap for the two species, there was no indication of competitive exclusion after comparing single versus mixed infections of the two species.

  3. Astragalus membranaceus (AM) enhances growth performance and antioxidant stress profiles in bluegill sunfish (Lepomis macrochirus).

    Science.gov (United States)

    Elabd, Hiam; Wang, Han-Ping; Shaheen, Adel; Yao, Hong; Abbass, Amany

    2016-06-01

    This study was designed to assess the potential effects of Astragalus membranaceus (AM) on the growth performance and antioxidative stress response in bluegill sunfish (Lepomis macrochirus) exposed to challenging cold water temperature conditions. In this regard, fish with an average weight of 43 ± 1 g were divided into four groups and fed daily with an AM-free diet (control), and 1.5, 3, and 4.5 % (w/w) AM-incorporated diets for an 8-week period. Oxidative stress response, biochemical, and growth parameters were measured, and subgroups of fish were exposed to the outside challenging cold pond water temperature (1.6-9.9 °C) with an average of 7.0 ± 0.1 °C beyond the optimal temperature. The results showed that incorporating AM in the diet significantly improved growth performance parameters (body mass gain, specific growth rate, length, condition factor, and feed conversion ratio) and biochemicals (aspartate aminotransferase and alanine transaminase activities, and glucose and cortisol concentrations). In addition, markedly up-regulated superoxide dismutase, glutathione peroxidase, and catalase activities were observed in AM-treated fish groups over the control. Conclusively, feeding AM diets significantly increased (P warm water fish. These findings are considered to be of great importance for sustainable aquaculture. PMID:26729192

  4. Three-dimensional analysis of scale morphology in bluegill sunfish, Lepomis macrochirus.

    Science.gov (United States)

    Wainwright, Dylan K; Lauder, George V

    2016-06-01

    Fish scales are morphologically diverse among species, within species, and on individuals. Scales of bony fishes are often categorized into three main types: cycloid scales have smooth edges; spinoid scales have spines protruding from the body of the scale; ctenoid scales have interdigitating spines protruding from the posterior margin of the scale. For this study, we used two- and three-dimensional (2D and 3D) visualization techniques to investigate scale morphology of bluegill sunfish (Lepomis macrochirus) on different regions of the body. Micro-CT scanning was used to visualize individual scales taken from different regions, and a new technique called GelSight was used to rapidly measure the 3D surface structure and elevation profiles of in situ scale patches from different regions. We used these data to compare the surface morphology of scales from different regions, using morphological measurements and surface metrology metrics to develop a set of shape variables. We performed a discriminant function analysis to show that bluegill scales differ across the body - scales are cycloid on the opercle but ctenoid on the rest of the body, and the proportion of ctenii coverage increases ventrally on the fish. Scales on the opercle and just below the anterior spinous dorsal fin were smaller in height, length, and thickness than scales elsewhere on the body. Surface roughness did not appear to differ over the body of the fish, although scales at the start of the caudal peduncle had higher skew values than other scales, indicating they have a surface that contains more peaks than valleys. Scale shape also differs along the body, with scales near the base of the tail having a more elongated shape. This study adds to our knowledge of scale structure and diversity in fishes, and the 3D measurement of scale surface structure provides the basis for future testing of functional hypotheses relating scale morphology to locomotor performance. PMID:27062451

  5. Aggressive interactions between the invasive Rio Grande cichlid (Herichthys cyanoguttatus) and native bluegill (Lepomis macrochirus), with notes on redspotted sunfish (Lepomis miniatus)

    Science.gov (United States)

    Lorenz, O. Thomas; O' Connell, Martin T.; Schofield, Pamela J.

    2010-01-01

    The Rio Grande cichlid (Herichthys cyanoguttatus) has been established in the Greater New Orleans Metropolitan area for at least 20 years, and its effect on native fishes is unknown. Behavioral trials were performed to determine if aggressive interactions occur between invasive H. cyanoguttatus and native bluegill (Lepomis macrochirus). When defending a territory as the resident, L. macrochirus were markedly aggressive, averaging 11.6 aggressive actions per lO-min behavioral trial. In contrast, L. macrochirus were extremely passive as invaders, with 0.5 aggressive actions per trial. Herichthys cyanoguttatus were equally aggressive as residents and as invaders, averaging 4.9 and 6.0 aggressive actions per trial, respectively. Herichthys cyanoguttatus interacted aggressively with native species whether they held territory or not, indicating that this invasive species may have fundamentally different strategies of aggression compared with native L. macrochirus. These differences may explain the continued success of H. cyanoguttatus as an invasive fish in southeastern Louisiana.

  6. Nestling recognition via direct cues by parental male bluegill sunfish ( Lepomis macrochirus).

    Science.gov (United States)

    Neff, Bryan D; Sherman, Paul W

    2003-06-01

    Parental care can be costly to a parent in terms of both time and energy invested in the young. In species with cuckoldry or brood parasitism not all of the young under a parent's care are necessarily offspring. In such cases, distinguishing between kin and non-kin, and investing only in the former (nepotism), can be advantageous. Bluegill sunfish ( Lepomis macrochirus) are characterized by paternal care and cuckoldry, and care-providing males appear to show nepotistic behaviours. Here, we investigated nestling recognition in bluegill, determining whether parental males can differentiate between young from their own nest (familiar and related) and young from non-neighbouring nests (unfamiliar and unrelated) using (1) visual and chemical cues, and (2) chemical cues only. In the first experiment, wild-caught parental males were presented with samples of eggs or fry (newly hatched eggs) collected from their own nest or a foreign nest and placed on opposite sides of an aquarium. The time these parental males spent associating with each sample, and their "pecking" behaviours (indicating cannibalism), were recorded. Parental males showed no preference between eggs from their own nest and eggs from a non-neighbouring nest, but they preferred to associate with fry from their own nest over foreign fry. There also was a positive relationship between male body size and the time spent associated with fry from their own nest. Parental males pecked at foreign fry more than 5 times as often as fry from their own nest, though this difference was not statistically significant. In the second experiment, fry that were collected from the nest of a wild-caught parental male or a non-neighbouring nest were placed in different containers and the water from each was dripped into opposite ends of an aquarium. The time the male spent on each side was recorded. In this case, parental males spent more time near the source of water conditioned by unrelated fry, but there was a positive

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

    Science.gov (United States)

    Wildhaber, Mark L.; Crowder, Larry B.

    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. Recruitment of helminth parasites by bluegills (Lepomis macrochirus) using a modified live-box technique. [Pomphorhynchus bulbocolli; Leptorhynchoides thecatus

    Energy Technology Data Exchange (ETDEWEB)

    Esch, G.W. (Wake Forest Univ., Winston-Salem, NC); Campbell, G.C.; Conners, R.E.; Coggins, J.R.

    1976-05-01

    A modification of the live-box technique was used in studying the recruitment of helminth parasites by bluegills, Lepomis macrochirus, during the summer of 1973 to 1974 in Gull Lake, Kalamazoo County, Michigan. Simultaneously, an approximately even number of L. macrochirus were captured by hook and line and the parasite fauna compared with that of tethered bluegills. The results show that the nature of the parasite faunas in the two groups of fish is similar. Results of tether experiments indicate that the acanthocephalan, Pomphorhynchus bulbocolli, was recruited at a higer rate early in the summer, then declined while Leptorhynchoides thecatus was initially recruited slowly, then increased in rate as P. bulbocolli was declining. The spatial distribution of L. thecatus indicated a preference for the ceca and anterior two-thirds of the intestine while P. bulbocolli localized most frequently in the anterior two-thirds of the intestine. While there was a zone of overlap for the two species, there was no indication of competitive exclusion after comparing single versus mixed infections of the two species.

  9. Amount and identity of (/sup 14/C) residues in bluegills (Lepomis macrochirus) exposed to (/sup 14/C)triclopyr

    Energy Technology Data Exchange (ETDEWEB)

    Lickly, T.D.; Murphy, P.G.

    1987-01-01

    The level and identity of (/sup 14/C) residues in bluegills (Lepomis macrochirus) exposed to 2.5 mg/L (/sup 14/C) triclopyr (3,5,6-trichloro-2-pyridinyloxyacetic acid) have been determined. The highest level of radioactivity observed in the flesh of a fish at any time point (0.13 mg/kg, calculated as equivalent mg triclopyr/kg fish) was less than 5% of the fish exposure level of 2.5 mg/L, while the maximum level in the remainder (head, skin, and viscera) was about 95% (2.33 mg/kg) of the fish exposure level, indicating no concentrating effect. The principal components observed in the fish tissues were triclopyr, 3,5,6-trichloro-2-pyridinol, 2-methoxy-3,5,6-trichloropyridine and a conjugate. These components accounted for greater than 75% of all the residues observed.

  10. Amount and identity of [14C] residues in bluegills (Lepomis macrochirus) exposed to [14C]triclopyr

    International Nuclear Information System (INIS)

    The level and identity of [14C] residues in bluegills (Lepomis macrochirus) exposed to 2.5 mg/L [14C] triclopyr (3,5,6-trichloro-2-pyridinyloxyacetic acid) have been determined. The highest level of radioactivity observed in the flesh of a fish at any time point (0.13 mg/kg, calculated as equivalent mg triclopyr/kg fish) was less than 5% of the fish exposure level of 2.5 mg/L, while the maximum level in the remainder (head, skin, and viscera) was about 95% (2.33 mg/kg) of the fish exposure level, indicating no concentrating effect. The principal components observed in the fish tissues were triclopyr, 3,5,6-trichloro-2-pyridinol, 2-methoxy-3,5,6-trichloropyridine and a conjugate. These components accounted for greater than 75% of all the residues observed

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

    International Nuclear Information System (INIS)

    The ratio of the bioaccumulation factors for 32P and phosphorus was determined for edible tissue in two species of freshwater fish by measuring the specific activity (32P activity per milligram phosphorus) in muscle relative to feed. The 32P 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 32P 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 32P 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 32P 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 32P 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

  12. The effects of urbanization on Lepomis macrochirus using the comet assay

    Science.gov (United States)

    Urbanization has been linked to increased concentrations of polycyclic aromatic hydrocarbons in natural waterways. This study was designed to examine the impact of urbanization and a wastewater treatment plant by investigating the impact on field-collected bluegill (Lepomis macr...

  13. Biodiversity data mining from Argus-eyed citizens: the first illegal introduction record of Lepomis macrochirus macrochirus Rafinesque, 1819 in Japan based on Twitter information.

    Science.gov (United States)

    Miyazaki, Yusuke; Teramura, Akinori; Senou, Hiroshi

    2016-01-01

    An apparent illegal introduction of Lepomis macrochirus macrochirus from Yokohama City, Kanagawa Prefecture, Japan, is reported based on a juvenile specimen and a photograph of two adults collected on 14 June 2015 and deposited in the Kangawa Prefectural Museum of Natural History. The specimens and photographs were initially reported on the internet-based social networking site, Twitter. Two specimens of Carassius auratus, including an aquarium form, were also reported at the same locality and date, suggesting that the illegal introductions originated from an aquarium release. Our report demonstrates an example of web data mining in the discipline of Citizen Science. PMID:27110154

  14. 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.

  15. Complex foraging polymorphism in bluegill sunfish

    OpenAIRE

    Ehlinger, Timothy John; Wilson, David Sloan

    1988-01-01

    The bluegill sunfish (Lepomis macrochirus) is considered a generalist predator, adept at feeding in both the littoral and open-water habitats of North American freshwater lakes. We demonstrate adaptive intraspecific variation in morphology and foraging behaviors within single lakes. This variation appears to make individual fish specialized for feeding in either the littoral or open-water habitat. Discovery of a complex polymorphism in such a well-studied species suggests that adaptive variat...

  16. Excretion of 131I by freshwater catfish (Ictalurus punctatus) and bluegill (Lepomis macrochirus)

    International Nuclear Information System (INIS)

    Fish in waters to which wastes from nuclear power stations are discharged accumulate radionuclides for a short time during batch discharges and then eliminate them during the longer intervals between discharges. Hence, the elimination rates of radionuclides are of importance in computing radiation doses to humans who eat fish caught in these waters. The excretion rates of 131I in two freshwater fish species were studied. Findings show that 131I is excreted quite rapidly by both species. 131I loss from fish muscle during deep frying was also measured and found to be 20 +- 4%. It is concluded that the practice of simply applying a concentration factor to convert the concentration in water to that in fish, without considering excretion, grossly overestimates the dose to the consumer, and that further studies should be made to identify other nuclides that behave similarly. (author)

  17. Seasonal and diel habitat selection by bluegills in a shallow natural lake

    Science.gov (United States)

    Paukert, C.P.; Willis, D.W.

    2002-01-01

    Habitat use by bluegill Lepomis macrochirus may be dictated by the avoidance of predators and the availability of prey. Previous work suggests that bluegills large enough to avoid predators will select habitats based on foraging profitability. However, these studies focused on smaller fish (200 mm total length [TL]) bluegills in a shallow (mean depth = 1.2 m), 332-ha, natural lake (Pelican Lake, Nebraska) with both emergent and submergent vegetation distributed throughout. A total of 78 bluegills (200-273 mm TL) were implanted with radio transmitters and relocated daily for 6 d per month (April-September); up to 20 of the tagged fish were relocated every 2 h for a 24-h period once each month. Regardless of diel period, bluegills used open-water, emergent vegetation, submergent vegetation, and mixed emergent - submergent vegetation habitat types in similar proportions. During April, June, and July, male bluegills positively selected emergent vegetation, whereas female bluegills showed no vegetation selection preference during any month. Throughout the study period, bluegills never avoided open-water habitats, suggesting that larger individuals may continue to use open-water habitats in proportion to their availability. In addition, emergent vegetation appeared to be important, particularly for male bluegills. Although the mechanism for the positive selection of emergent vegetation by males was unclear, the protection or enhancement of such habitats may facilitate the preservation of quality bluegill populations in shallow lakes.

  18. Dorsal and anal fin function in bluegill sunfish Lepomis macrochirus: three-dimensional kinematics during propulsion and maneuvering.

    Science.gov (United States)

    Standen, E M; Lauder, G V

    2005-07-01

    Dorsal and anal fins are median fins located above and below the centre of mass of fishes, each having a moment arm relative to the longitudinal axis. Understanding the kinematics of dorsal and anal fins may elucidate how these fins are used in concert to maintain and change fish body position and yet little is known about the functions of these fins. Using three synchronized high-speed cameras (500 frames s(-1)) we studied the three-dimensional kinematics of dorsal and anal fins during steady swimming (0.5-2.5 TL s(-1), where TL = total length) and during slow speed maneuvers (0.5 TL s(-1)). By digitizing points along every other fin ray in the soft-rayed portion of the fins we were able to determine not only the movement of the fin surface but also the curvature of individual fin rays and the resulting fin surface shape. We found that dorsal and anal fins begin oscillating, in phase, at steady swimming speeds above 1.0 TL s(-1) and that maximum lateral displacement of the trailing edge of the fins as well as fin area increase with increasing steady swimming speed. Differences in area, lateral displacement and moment arm between the dorsal and anal fin suggest that dorsal and anal fins produce balancing torques during steady swimming. During maneuvers, fin area is maximized and mean lateral excursion of both fins is greater than during steady swimming, with large variation among maneuvers. Fin surface shape changes dramatically during maneuvers. At any given point in time the spanwise (base to tip) curvature along fin rays can differ between adjacent rays, suggesting that fish have a high level of control over fin surface shape. Also, during maneuvers the whole surface of both dorsal and anal fins can be bent without individual fin rays exhibiting significant curvature. PMID:16000544

  19. Elevated selenium levels in bluegills and their effect on reproduction

    International Nuclear Information System (INIS)

    A series of 18 artificial crosses of bluegills, Lepomis macrochirus, from Hyco Reservoir, North Carolina (mean Se = 7.94 ppm) and Roxboro City Lake, North Carolina (mean Se = 0.38 ppm) were generated. Neither percent fertilization nor percent hatch differed significantly among the parent combinations. However, all crosses of females with high Se body burdens resulted in larvae with edema; larvae from all crosses of females with low Se body burdens were normal. No differences were found in morphology of the membranes from immature ova between females of the two reservoirs. Sections of heart and intestines appear similar between larvae from females of Hyco Reservoir and Roxboro City Lake suggesting that edema occurs from physiological impairment and not from developmental abnormalities. Mean Se levels in the gonads and carcass of adult bluegills were more than 20 times higher in fishes from Hyco Reservoir than in those from Roxboro City Lake. The high Se concentration in ovaries of Hyco Reservoir bluegills, coupled with high Se levels in larvae from artificial crosses indicated that Se was transferred from females to offspring and resulted in larval edema. 75Se-selenomethionine was fed to adult bluegills. After 12 weeks of feeding, liver and testis had the highest 75Se activities according to gamma activity assays while ovary, heart and skeletal muscle had the lowest activities

  20. Induction of lauric acid omega-hydroxylation by peroxisomal proliferators in bluegill and catfish

    Energy Technology Data Exchange (ETDEWEB)

    Haasch, M.L. [Univ. of Maryland, Solomons, MD (United States); Henderson, M.C.; Buhler, D.R. [Oregon State Univ. Corvallis, OR (United States)

    1995-12-31

    Peroxisome proliferating agents (PPAs) are a structurally diverse group of chemicals that include environmental chemical contaminants such as certain chlorinated herbicides, solvents and plasticizers. PPAs have previously been shown to induce anti-trout laruci acid hydroxylase immunoreactive proteins in bluegill and catfish. In this investigation, induction of lauric acid hydroxylase activity and immunoreactive proteins was confirmed, and the mass spectral analysis of specific hydroxylation products was performed in order to identify possible species-specific differences in fatty acid metabolism. Male bluegill (Lepomis macrochirus) and channel catfish (Ictalurus punctatus) were administered clofibrate or ciprofibrate 48 hr prior to hepatic or trunk kidney (catfish only) microsome preparation. While no significant differences were observed in male catfish, male bluegill had significant decreases in hematocrit and plasma protein indicating hemodilution due to possible gill or kidney damage. Both bluegill and catfish exhibited induction of hepatic and kidney (catfish only) anti-trout lauric acid hydroxylase immunoreactive proteins. In general, total metabolism of lauric acid was greater, and higher levels of wP2, wP3, and wP4 products were produced in control catfish than in juvenile male trout. In male bluegill, lauric acid hydroxylation products wP, wP4 and wP5 were significantly induced by clofibrate treatment. Taken together the above data indicate that peroxisome proliferation may be an important consideration for responsive species exposed to PPAs by environmental chemical contamination.

  1. 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.

  2. Experimental Infections of Bluegill with the Trematode Ribeiroia ondatrae (Digenea: Cathaemasiidae): Histopathology and Hematological Response.

    Science.gov (United States)

    Calhoun, Dana M; Schaffer, Paula A; Gregory, Jacklyn R; Hardy, Katherine M; Johnson, Pieter T J

    2015-12-01

    Infections by the digenetic trematode, Ribeiroia ondatrae, cause severe limb malformations in many North American amphibians. Ribeiroia ondatrae also infects fishes as second intermediate hosts, but less is known about the pathology and immune responses initiated in infected fish, even though reports of infected fish date back to early 1900s. To this end, we experimentally exposed juvenile Bluegills Lepomis macrochirus to three doses of R. ondatrae cercariae and monitored the pathology, parasite infection success, and humoral responses over 648 h. All exposed fish became infected with metacercariae, and the average infection load increased with exposure dose. Histologically, infection was associated with acute hemorrhages in the lateral line and local dermis at 36 h, followed by progressive granulomatous inflammation that led to the destruction of encysted metacercariae. Correspondingly, over the course of 648 h we observed an 85% decline in average infection load among hosts, reflecting the host's clearance of the parasite. Infection was not associated with changes in fish growth or survival, but did correlate with leukocytosis and neutrophilia in circulating host blood. Understanding the physiological responses of R. ondatrae in Bluegill will help to clarify the ecological effects of this parasite and provide a foundation for subsequent comparisons into its effects on behavior, individual health, and population dynamics of Bluegill. PMID:26587684

  3. 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.

  4. 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.

  5. FISH COUGH RESPONSE - A METHOD FOR EVALUATING QUALITY OF TREATED COMPLEX EFFLUENTS

    Science.gov (United States)

    Bluegill sunfish (Lepomis macrochirus) showed increases in cough frequency commensurate with effluent concentration when exposed for 24 h to different industrial and municipal effluents. Effluents known to be toxic caused steadily increasing cough rates in the fish as effluent co...

  6. ACUTE AND CHRONIC TOXICITY OF CHLORDANE TO FISH AND INVERTEBRATES

    Science.gov (United States)

    The acute and chronic toxicity of technical chlordane to bluegill (Lepomis macrochirus), fathead minnow (Pimephales promelas), brook trout (Salvelinus fontinalis), Daphnia magna, Hyallela azteca, and Chironomus No. 51 were determined with flow-through conditions. The purpose was ...

  7. 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...

  8. 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...

  9. 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)

    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

  10. Effects of endosulfan on brain acetylcholinesterase activity in juvenile bluegill sunfish

    International Nuclear Information System (INIS)

    The effects of endosulfan upon brain acetylcholinesterase (AChE) activity were measured in juvenile blue gill sunfish (Lepomis macrochirus). Based on exposure durations of 0, 24, 48, 72, and 96 h and 1 week at 1.0 μg/L (just below the LC50 of 1.2 μg/L for this species), step-wise decreases in AChE activity were noted, corresponding to 0%, 3.57%, 12.65%, 14.23%, 16.31%, and 3.11% inhibition, respectively. Total brain protein concentrations were measured to test the accuracy of the Ache data with no significant anomalies. The duration of exposure was related to the reduction in the AChE activities which reflected the biotoxicity of endosulfan. The changes in the AChE activities will certainly affect the normal behavior of the juvenile blue gill which is detrimental to their very existence in the natural habitat

  11. LARVAL FEEDING AND RAPID MATURATION OF BLUEGILLS IN THE LABORATORY

    Science.gov (United States)

    Bluegill larvae were raised in the laboratory with a high percentage of survival using newly hatched San Francisco brine shrimp nauplii as a first food. Utah brine shrimp nauplii and older San Francisco nauplii were too large for a bluegill first food. Bluegills were raised to ma...

  12. Bioaccumulation of P-32 in bluegill and catfish

    International Nuclear Information System (INIS)

    Bluegill and catfish were fed P-32 at a constant feeding rate per body weight to determine the bioaccummulation factor (BF/sub r/) for P-32 in muscle relative to water. The fish were maintained in flow-through tanks at two feeding levels. The bluegill accumulated P-32 for 51 days, followed by depuration for 28 days. The catfish study had to be teminated after 11 days. Fish were analyzed in triplicte for P-32 and phosphorus at intervals of 1 to 8 days. Additional aquaria experiments were performed to determine the effects of water temperature, feeding rate, and type of food (worms vs. pellets) on P-32 uptake, and to observe P-32 uptake from water by unfed fish (including fish with blocked esophagus). A simple calculational model was used to determine the phosphorus turnover constant from the specific activity in tissue relative to food. This ratio at steady state approaches the BF/sub r/BF ratio (where BF is the phosphorus bioaccumulation factor) if P-32 transfers rapidly from water to food. The bluegill showed a weight gain of 0.2 %/d, a phosphorous turnover constant in muscle of 0.43 %/d, and a BF/sub r//BF ratio of 0.081 at the higher feeding rate, and 0.05 %/d, 0.34 %/d, and 0.064 at the lower feeding rate. Hence, respective P-32 BF/sub r/ values are 6000 and 4000 at a phosphorus BF of 70,000. The BF/sub r/ values for catfish were approximately twice as high. The aquarium experiments suggest that the higher factors are due to a much higher phosphorus intake, higher water temperature, higher retention from pellets than from worms, and possible higher retention by catfish than bluegill under the same conditions. 36 references, 15 figures, 22 tables

  13. Otolith chemistry of prey fish consumed by a fish predator: does digestion hinder Russian doll techniques?

    Science.gov (United States)

    Phelps, Q E; Noatch, M R; Lewis, H A; Myers, D J; Zeigler, J M; Eichelberger, J S; Saltzgiver, M J; Whitledge, G W

    2009-12-01

    The effect of digestion by a predatory fish (largemouth bass Micropterus salmoides) on stable isotopic (delta(13)C and delta(18)O) and trace elemental (Sr:Ca and Ba:Ca) compositions of prey fish (bluegill Lepomis macrochirus) otoliths was investigated in a laboratory experiment. Trace element and stable-isotopic signatures of L. macrochirus otoliths were not significantly altered for up to 16 h after L. macrochirus were consumed by M. salmoides. Prey fish otoliths recovered from predator digesta can retain environmental stable isotopic and trace elemental signatures, suggesting that determination of environmental history for prey fishes by stable-isotope and trace-element analysis of otoliths recovered from stomachs of piscivorous fishes will be feasible. PMID:20738510

  14. Behavioural interaction between fish predators and their prey: effects of plant density

    Science.gov (United States)

    Savino, Jacqueline F.; Stein, Roy A.

    1989-01-01

    Prey-specific anti-predatory behaviour under different degrees of structural complexity determines foraging success of predators. The behaviour of piscivorous fish (largemouth bass, Micropterus salmoides and northern pike, Esox lucius) and their prey (bluegills, Lepomis macrochirus, and fathead minnows, Pimephales promelas) were quantified in 60-min experiments in laboratory pools (2 multiplied by 4 m in diameter, 0 multiplied by 5 m deep) with artificial vegetation at densities of 0, 50, 250, and 1000 stems/m2. Largemouth bass switched predatory tactics from searching to ambushing as plant density increased whereas northern pike always used ambushing. At high plant density, both predators captured minnows, but not bluegills. Bluegills modified their behaviour more than minnows in response to predators, thereby avoiding predation at high plant densities. Structural complexity alone did not always provide refuge for prey; prey must use the structure to avoid predators. Predators may seek vegetated areas if appropriate, vulnerable prey are present.

  15. Quantification of flow during suction feeding in bluegill sunfish.

    Science.gov (United States)

    Ferry-Graham, Lara A; Wainwright, Peter C; Lauder, George V

    2003-01-01

    Nearly all aquatic-feeding vertebrates use some amount of suction to capture prey items. Suction prey capture occurs by accelerating a volume of water into the mouth and taking a prey item along with it. Yet, until recently, we lacked the necessary techniques and analytical tools to quantify the flow regime generated by feeding fish. We used a new approach; Digital Particle Image Velocimetery (DPIV) to measure several attributes of the flow generated by feeding bluegill sunfish. We found that the temporal pattern of flow was notably compressed during prey capture. Flow velocity increased rapidly to its peak within 20 ms of the onset of the strike, and this peak corresponded to the time that the prey entered the mouth during capture. The rapid acceleration and deceleration of water suggests that timing is critical for the predator in positioning itself relative to the prey so that it can be drawn into the mouth along with the water. We also found that the volume of water affected by suction was spatially limited. Only rarely did we measure significant flow beyond 1.75 cm of the mouth aperture (in 20 cm fish), further emphasizing the importance of mechanisms, like locomotion, that place the fish mouth in close proximity to the prey. We found that the highest flows towards the mouth along the fish midline were generated not immediately in front of the open mouth, but approximately 0.5 cm anterior to the mouth opening. Away from the midline the peak in flow was closer to the mouth. We propose that this pattern indicates the presence of a bow wave created by the locomotor efforts of the fish. In this scheme, the bow wave acts antagonistically to the flow of water generated by suction, the net effect being to push the region of peak flow away from the open mouth. The peak was located farther from the mouth opening in strikes accompanied by faster locomotion, suggesting faster fish created larger bow waves. PMID:16351901

  16. Selenium and other trace metals in fish inhabiting a fly ash stream: Implications for regulatory tissue thresholds

    International Nuclear Information System (INIS)

    Bluegill sunfish (Lepomis macrochirus) and caddis flies (Trichoptera: Hydropsychidae) were collected from a stream receiving fly ash discharge and nearby reference streams to determine tissue levels of selenium (Se) and other metals, and compare these levels to published 'no effect' thresholds. Stingy Run samples contained elevated levels of several metals. Mean Se concentrations in bullhead minnow whole body, bluegill whole body, bluegill ovary, and testes tissues were 44.6, 17.3, 32.5, and 37.1 μg/g (dry wt), respectively. These levels were 2-3 times higher than proposed toxic thresholds for fish whole body (7.9 μg/g) and ovary (17 μg/g). Although monitoring indicated a persistent bluegill population, some reproductive impairment may have occurred. Tissue residue data should be treated with caution because feral fish may accumulate several metals. In Stingy Run, persistence of a bluegill population may be explained by antagonistic interactions with other metals that were also elevated in the fish. - Bluegill sunfish inhabiting a coal fly ash receiving stream had elevated selenium levels in whole body and gonad tissue (9-10 times higher than reference fish), and antagonistic metal interactions may be one of several mechanisms allowing long-term persistence of the population

  17. Growth and condition of bluegills in Wisconsin lakes: effects of population density and lake pH

    Science.gov (United States)

    Wiener, J.G.; Hanneman, W.R.

    1982-01-01

    Growth and condition of bluegills epomis macrochirusfrom five acidic lakes (pH 5.1-6.0) and six circumneutral lakes (pH 6.7-7.5) in northern Wisconsin were compared. Although mean condition factors and mean back-calculated total lengths at ages 1 to 4 varied significantly among lakes, the differences were not related to lake pH. Rather, the ranks of mean condition factors and back-calculated lengths at ages 2, 3, and 4 were negatively correlated with relative density of bluegills among the lakes. Because of the dominating effect of density, growth rates and condition factors are not useful as indicators of chronic, pH-related stress on bluegill populations.

  18. Infestation of Lernaea cyprinacea (Copepoda: Lernaeidae in two invasive fish species in Romania, Lepomis gibbosus and Pseudorasbora parva

    Directory of Open Access Journals (Sweden)

    Stavrescu-Bedivan M.M.

    2014-01-01

    Full Text Available In this study we analyzed comparatively the host-parasite associations between two fish host species invasive in Europe (Lepomis gibbosus and Pseudorasbora parva and one known generalist parasite species, the copepod Lernaea cyprinacea. We used a fragment of the hypervariable region D1-D2 of the 28S rRNA to confirm that the copepod specimens collected on both host species in our study are indeed conspecific. The prevalence of infection was significantly different between the two host species in all three aquatic ecosystems. Two populations of L. gibbosus exhibited a positive correlation coefficient between the standard body length and infection intensity, while a negative correlation coefficient was observed in one population of P. parva. This is one of the few studies providing parasitological parameters of infections of Lernaea cypriancea in Lepomis gibbosus and Pseudorasbora parva.

  19. Scaling of suction-induced flows in bluegill: morphological and kinematic predictors for the ontogeny of feeding performance.

    Science.gov (United States)

    Holzman, Roi; Collar, David C; Day, Steven W; Bishop, Kristin L; Wainwright, Peter C

    2008-08-01

    During ontogeny, animals undergo changes in size and shape that result in shifts in performance, behavior and resource use. These ontogenetic changes provide an opportunity to test hypotheses about how the growth of structures affects biological functions. In the present study, we ask how ontogenetic changes in skull biomechanics affect the ability of bluegill sunfish, a high-performance suction feeder, to produce flow speeds and accelerations during suction feeding. The flow of water in front of the mouth was measured directly for fish ranging from young-of-year to large adults, using digital particle imaging velocimetry (DPIV). As bluegill size increased, the magnitude of peak flow speed they produced increased, and the effective suction distance increased because of increasing mouth size. However, throughout the size range, the timing of peak fluid speed remained unchanged, and flow was constrained to approximately one gape distance from the mouth. The observed scaling relationships between standard length and peak flow speed conformed to expectations derived from two biomechanical models, one based on morphological potential to produce suction pressure (the Suction Index model) and the other derived from a combination of morphological and kinematic variables (the Expanding Cone model). The success of these models in qualitatively predicting the observed allometry of induced flow speed reveals that the scaling of cranial morphology underlies the scaling of suction performance in bluegill. PMID:18689419

  20. Activation of muscarinic acetylcholine receptors elicits pigment granule dispersion in retinal pigment epithelium isolated from bluegill

    Directory of Open Access Journals (Sweden)

    Crittenden Elizabeth L

    2004-07-01

    Full Text Available Abstract Background In fish, melanin pigment granules in the retinal pigment epithelium disperse into apical projections as part of the suite of responses the eye makes to bright light conditions. This pigment granule dispersion serves to reduce photobleaching and occurs in response to neurochemicals secreted by the retina. Previous work has shown that acetylcholine may be involved in inducing light-adaptive pigment dispersion. Acetylcholine receptors are of two main types, nicotinic and muscarinic. Muscarinic receptors are in the G-protein coupled receptor superfamily, and five different muscarinic receptors have been molecularly cloned in human. These receptors are coupled to adenylyl cyclase, calcium mobilization and ion channel activation. To determine the receptor pathway involved in eliciting pigment granule migration, we isolated retinal pigment epithelium from bluegill and subjected it to a battery of cholinergic agents. Results The general cholinergic agonist carbachol induces pigment granule dispersion in isolated retinal pigment epithelium. Carbachol-induced pigment granule dispersion is blocked by the muscarinic antagonist atropine, by the M1 antagonist pirenzepine, and by the M3 antagonist 4-DAMP. Pigment granule dispersion was also induced by the M1 agonist 4-[N-(4-chlorophenyl carbamoyloxy]-4-pent-2-ammonium iodide. In contrast the M2 antagonist AF-DX 116 and the M4 antagonist tropicamide failed to block carbachol-induced dispersion, and the M2 agonist arecaidine but-2-ynyl ester tosylate failed to elicit dispersion. Conclusions Our results suggest that carbachol-mediated pigment granule dispersion occurs through the activation of Modd muscarinic receptors, which in other systems couple to phosphoinositide hydrolysis and elevation of intracellular calcium. This conclusion must be corroborated by molecular studies, but suggests Ca2+-dependent pathways may be involved in light-adaptive pigment dispersion.

  1. 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]).

  2. Linear and nonlinear models for predicting fish bioconcentration factors for pesticides.

    Science.gov (United States)

    Yuan, Jintao; Xie, Chun; Zhang, Ting; Sun, Jinfang; Yuan, Xuejie; Yu, Shuling; Zhang, Yingbiao; Cao, Yunyuan; Yu, Xingchen; Yang, Xuan; Yao, Wu

    2016-08-01

    This work is devoted to the applications of the multiple linear regression (MLR), multilayer perceptron neural network (MLP NN) and projection pursuit regression (PPR) to quantitative structure-property relationship analysis of bioconcentration factors (BCFs) of pesticides tested on Bluegill (Lepomis macrochirus). Molecular descriptors of a total of 107 pesticides were calculated with the DRAGON Software and selected by inverse enhanced replacement method. Based on the selected DRAGON descriptors, a linear model was built by MLR, nonlinear models were developed using MLP NN and PPR. The robustness of the obtained models was assessed by cross-validation and external validation using test set. Outliers were also examined and deleted to improve predictive power. Comparative results revealed that PPR achieved the most accurate predictions. This study offers useful models and information for BCF prediction, risk assessment, and pesticide formulation. PMID:27183335

  3. Laboratory studies of the effects of pressure and dissolved gas supersaturation on turbine-passed fish

    Energy Technology Data Exchange (ETDEWEB)

    Abernethy, C. S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Amidan, B. G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Cada, G. F. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2001-03-01

    Designing advanced turbine systems requires knowledge of environmental conditions that injure or kill fish such as the stresses associated with hydroelectric power production, including pressure changes fish experience during turbine passage and dissolved gas supersaturation (resulting from the release of water from the spillway). 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. The study 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. 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; Barber, Larry B; Writer, Jeffery H; Rosenberry, Donald O; Kiesling, Richard L; Lundy, James R; Schoenfuss, Heiko L

    2014-10-01

    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. PMID:24974177

  5. Uranium bioaccumulation in a freshwater ecosystem: Impact of feeding ecology

    Energy Technology Data Exchange (ETDEWEB)

    Kraemer, Lisa D., E-mail: lisakraemer@trentu.ca [Trent University, 1600 West Bank Drive, Peterborough, ON, K9J 7B8 (Canada); Evans, Douglas [Trent University, 1600 West Bank Drive, Peterborough, ON, K9J 7B8 (Canada)

    2012-11-15

    Uranium bioaccumulation in a lake that had been historically affected by a U mine and (2) to use a combined approach of gut content examination and stable nitrogen and carbon isotope analysis to determine if U bioaccumulation in fish was linked to foodweb ecology. We collected three species of fish: smallmouth bass (Micropterus dolomieu), yellow perch (Perca flavescens) and bluegill (Lepomis macrochirus), in addition to several invertebrate species including freshwater bivalves (family: Sphaeriidae), dragonfly nymphs (order: Odonata), snails (class: Gastropoda) and zooplankton (family: Daphniidae). Results showed significant U bioaccumulation in the lake impacted by historical mining activities. Uranium accumulation was 2-3 orders of magnitude higher in invertebrates than in the fish species. Within fish, U was measured in operculum (bone), liver and muscle tissue and accumulation followed the order: operculum > liver > muscle. There was a negative relationship between stable nitrogen ratios ({sup 15}N/{sup 14}N) and U bioaccumulation, suggesting U biodilution in the foodweb. Uranium bioaccumulation in all three tissues (bone, liver, muscle) varied among fish species in a consistent manner and followed the order: bluegill > yellow perch > smallmouth bass. Collectively, gut content and stable isotope analysis suggests that invertebrate-consuming fish species (i.e. bluegill) have the highest U levels, while fish species that were mainly piscivores (i.e. smallmouth bass) have the lowest U levels. Our study highlights the importance of understanding the feeding ecology of fish when trying to predict U accumulation.

  6. Uranium bioaccumulation in a freshwater ecosystem: Impact of feeding ecology

    International Nuclear Information System (INIS)

    Uranium bioaccumulation in a lake that had been historically affected by a U mine and (2) to use a combined approach of gut content examination and stable nitrogen and carbon isotope analysis to determine if U bioaccumulation in fish was linked to foodweb ecology. We collected three species of fish: smallmouth bass (Micropterus dolomieu), yellow perch (Perca flavescens) and bluegill (Lepomis macrochirus), in addition to several invertebrate species including freshwater bivalves (family: Sphaeriidae), dragonfly nymphs (order: Odonata), snails (class: Gastropoda) and zooplankton (family: Daphniidae). Results showed significant U bioaccumulation in the lake impacted by historical mining activities. Uranium accumulation was 2–3 orders of magnitude higher in invertebrates than in the fish species. Within fish, U was measured in operculum (bone), liver and muscle tissue and accumulation followed the order: operculum > liver > muscle. There was a negative relationship between stable nitrogen ratios (15N/14N) and U bioaccumulation, suggesting U biodilution in the foodweb. Uranium bioaccumulation in all three tissues (bone, liver, muscle) varied among fish species in a consistent manner and followed the order: bluegill > yellow perch > smallmouth bass. Collectively, gut content and stable isotope analysis suggests that invertebrate-consuming fish species (i.e. bluegill) have the highest U levels, while fish species that were mainly piscivores (i.e. smallmouth bass) have the lowest U levels. Our study highlights the importance of understanding the feeding ecology of fish when trying to predict U accumulation.

  7. Browns Ferry biothermal research series. II. Effects of temperature on bluegill and walleye, and periphyton, macroinvertebrate, and zooplankton communities in experimental ecosystems. Research report

    International Nuclear Information System (INIS)

    Effects of long-term, March-September 1977, temperature elevations on aquatic communities in 12 outdoor experimental channels were evaluated. Macroinvertebrates, periphyton, and zooplankton colonized the channels naturally from the water supplied from Wheeler Reservoir, Tennessee River. The fish community consisted of stocked adult bluegill and juvenile walleye. Four temperature regimens, with three replicate channels per regimen, were maintained. The major objective of the study is to provide information for establishing temperature criteria for protection of important sport and commercial fish species

  8. 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.

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

    Directory of Open Access Journals (Sweden)

    Nicholas B D Phelps

    Full Text Available 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.

  10. Previous exposure of predatory fish to a pesticide alters palatability of larval amphibian prey.

    Science.gov (United States)

    Hanlon, Shane M; Parris, Matthew J

    2013-12-01

    Habitat preferences of organisms are reliant on a variety of factors. For amphibians specifically, preferences can depend on factors such as food availability, water quality, and the presence of potential predators. Because some amphibians breed in permanent bodies of water (e.g., ponds), the threat of predation (e.g., from fish) is constant. Thus, some amphibians are unpalatable to many predators, allowing them to coexist in the same habitats. However, the addition of anthropogenic stressors (i.e., pesticides) may alter the perceived palatability of prey items to predators. The authors tested the hypothesis that bluegill fish (Lepomis macrochirus), previously exposed to the pesticide carbaryl, would consume more unpalatable prey (Fowler's toad [Anaxyrus fowleri] tadpoles) than unexposed predators. Carbaryl is a pesticide that attacks the nervous system and is linked to taste sense in organisms. Moreover, the authors conducted an identical test using palatable prey (gray treefrog [Hyla versicolor] tadpoles) and predicted that no change in preference would be observed. In support of the primary hypothesis, bluegill exposed to the highest concentration of carbaryl consumed more A. fowleri tadpoles compared with those exposed to carbaryl at the lowest concentration or water control. Moreover, an effect of carbaryl on predation success on H. versicolor tadpoles was not observed. The present study shows that an anthropogenic stressor (carbaryl) can alter the perceived palatability of noxious prey to fish predators, potentially altering predator-prey relationships in natural settings. PMID:24383102

  11. Visibility from Roads Predict the Distribution of Invasive Fishes in Agricultural Ponds

    Science.gov (United States)

    Kizuka, Toshikazu; Akasaka, Munemitsu; Kadoya, Taku; Takamura, Noriko

    2014-01-01

    Propagule pressure and habitat characteristics are important factors used to predict the distribution of invasive alien species. For species exhibiting strong propagule pressure because of human-mediated introduction of species, indicators of introduction potential must represent the behavioral characteristics of humans. This study examined 64 agricultural ponds to assess the visibility of ponds from surrounding roads and its value as a surrogate of propagule pressure to explain the presence and absence of two invasive fish species. A three-dimensional viewshed analysis using a geographic information system quantified the visual exposure of respective ponds to humans. Binary classification trees were developed as a function of their visibility from roads, as well as five environmental factors: river density, connectivity with upstream dam reservoirs, pond area, chlorophyll a concentration, and pond drainage. Traditional indicators of human-mediated introduction (road density and proportion of urban land-use area) were alternatively included for comparison instead of visual exposure. The presence of Bluegill (Lepomis macrochirus) was predicted by the ponds' higher visibility from roads and pond connection with upstream dam reservoirs. Results suggest that fish stocking into ponds and their dispersal from upstream sources facilitated species establishment. Largemouth bass (Micropterus salmoides) distribution was constrained by chlorophyll a concentration, suggesting their lower adaptability to various environments than that of Bluegill. Based on misclassifications from classification trees for Bluegill, pond visual exposure to roads showed greater predictive capability than traditional indicators of human-mediated introduction. Pond visibility is an effective predictor of invasive species distribution. Its wider use might improve management and mitigate further invasion. The visual exposure of recipient ecosystems to humans is important for many invasive species that

  12. Uranium bioaccumulation in a freshwater ecosystem: impact of feeding ecology.

    Science.gov (United States)

    Kraemer, Lisa D; Evans, Douglas

    2012-11-15

    The objectives of our study were: (1) to determine if there was significant uranium (U) bioaccumulation in a lake that had been historically affected by a U mine and (2) to use a combined approach of gut content examination and stable nitrogen and carbon isotope analysis to determine if U bioaccumulation in fish was linked to foodweb ecology. We collected three species of fish: smallmouth bass (Micropterus dolomieu), yellow perch (Perca flavescens) and bluegill (Lepomis macrochirus), in addition to several invertebrate species including freshwater bivalves (family: Sphaeriidae), dragonfly nymphs (order: Odonata), snails (class: Gastropoda) and zooplankton (family: Daphniidae). Results showed significant U bioaccumulation in the lake impacted by historical mining activities. Uranium accumulation was 2-3 orders of magnitude higher in invertebrates than in the fish species. Within fish, U was measured in operculum (bone), liver and muscle tissue and accumulation followed the order: operculum>liver>muscle. There was a negative relationship between stable nitrogen ratios ((15)N/(14)N) and U bioaccumulation, suggesting U biodilution in the foodweb. Uranium bioaccumulation in all three tissues (bone, liver, muscle) varied among fish species in a consistent manner and followed the order: bluegill>yellow perch>smallmouth bass. Collectively, gut content and stable isotope analysis suggests that invertebrate-consuming fish species (i.e. bluegill) have the highest U levels, while fish species that were mainly piscivores (i.e. smallmouth bass) have the lowest U levels. Our study highlights the importance of understanding the feeding ecology of fish when trying to predict U accumulation. PMID:22963859

  13. TOXICITY AND METABOLISM STUDIES WITH EPA (ENVIRONMENTAL PROTECTION AGENCY) PRIORITY POLLUTANTS AND RELATED CHEMICALS IN FRESHWATER ORGANISMS

    Science.gov (United States)

    Twenty-two chemicals from the EPA priority pollutant list were studied for their acute and/or chronic toxicity to selected freshwater organisms. Freshwater species tested included the fathead minnow (Pimephales promelas), rainbow trout (Salmo gairdneri), bluegill sunfish (Lepomis...

  14. Ecological characterization of two species of exotic fish, pumpkinseed sunfish (Lepomis gibbosus and largemouth bass (Micropterus salmoides in the international Minho river

    Directory of Open Access Journals (Sweden)

    Ana Cristina Lages

    2015-11-01

    Full Text Available The introduction of exotic species is considered the main cause for the decline of native species. The largemouth bass (Micropterus salmoides and pumpkinseed sunfish (Lepomis gibbosus are two native species from North America, introduced in Portugal to enhance sport fishing. However, their diet and great adaptability made them considered predatory and harmful. In order to understand the ecological impact of M. salmoides and L. gibbosus in the international section of the Minho River, three sampling sites were selected: two in Vila Nova de Cerveira and one in Lapela, at distance of the mouth of the river of 17 and 45 Km, respectively. The fish were gathered using fyke nets and trammel nets, electric fishing and fishing rod, with performed samplings since July 2014 until October 2015. For all fish caught the biometric data (weight, total and fork length, gonad and liver weight, sex, stomach contents analysis were registered as well as collection of otoliths and scales for age reading. Both species feed on small macroinvertebrates specially the juveniles while adults of largemouth bass and pumpkinseed sunfish prefer eat fish and gastropods, respectively. Because L. gibbosus is a recent introduction in the Minho river estuary its abundance increased a lot in the last two years and it was possible verify the increase of the fish population average length. With this work it is intended to evaluate the impact in the Minho River estuary of both exotic species studying the population structure, trophic webs and reproduction.

  15. Small nonnative fishes as predators of larval razorback suckers

    Science.gov (United States)

    Carpenter, J.; Mueller, G.A.

    2008-01-01

    The razorback sucker (Xyrauchen texanus), an endangered big-river fish of the Colorado River basin, has demonstrated no sustainable recruitment in 4 decades, despite presence of spawning adults and larvae. Lack of adequate recruitment has been attributed to several factors, including predation by nonnative fishes. Substantial funding and effort has been expended on mechanically removing nonnative game fishes, typically targeting large predators. As a result, abundance of larger predators has declined, but the abundance of small nonnative fishes has increased in some areas. We conducted laboratory experiments to determine if small nonnative fishes would consume larval razorback suckers. We tested adults of three small species (threadfin shad, Dorosoma petenense; red shiner, Cyprinella lutrensis; fathead minnow, Pimephales promelas) and juveniles of six larger species (common carp, Cyprinus carpio; yellow bullhead, Ameiurus natalis; channel catfish, Ictalurus punctatus; rainbow trout, Oncorhynchus mykiss; green sunfish, Lepomis cyanellus; bluegill, L. macrochirus). These nonnative fishes span a broad ecological range and are abundant within the historical range of the razorback sucker. All nine species fed on larval razorback suckers (total length, 9-16 mm). Our results suggest that predation by small nonnative fishes could be responsible for limiting recovery of this endangered species.

  16. 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.

  17. Acute toxicity of metals and reference toxicants to a freshwater ostracod, Cypris subglobosa Sowerby, 1840 and correlation to EC{sub 50} values of other test models

    Energy Technology Data Exchange (ETDEWEB)

    Khangarot, B.S., E-mail: bkhangarot@hotmail.com [Ecotoxicology Division, Indian Institute of Toxicology Research (Formerly: Industrial Toxicology Research Centre), Post Box No. 80, Mahatma Gandhi Marg, Lucknow 226001 (India); Das, Sangita [Ecotoxicology Division, Indian Institute of Toxicology Research (Formerly: Industrial Toxicology Research Centre), Post Box No. 80, Mahatma Gandhi Marg, Lucknow 226001 (India)

    2009-12-30

    The ostracod Cypris subglobosa Sowerby, 1840 static bioassay test on the basis of a 48 h of 50% of immobilization (EC{sub 50}) has been used to measure the toxicity of 36 metals and metalloids and 12 reference toxicants. Among the 36 metals and metalloids, osmium (Os) was found to be the most toxic in the test while boron (B), the least toxic. The EC{sub 50} values of this study revealed positive linear relationship with the established test models of cladoceran (Daphnia magna), sludge worm (Tubifex tubifex), chironomid larvae (Chironomus tentans), protozoan (Tetrahymena pyriformis), fathead minnow (Pimephales promelas), bluegill sunfish (Lepomis macrochirus), and aquatic macrophyte duckweed (Lemna minor). Correlation coefficients (r{sup 2}) for 17 physicochemical properties of metals or metal ions and EC{sub 50}s (as pM) were examined by linear regression analysis. The electronegativity, ionization potential, melting point, solubility product of metal sulfides (pK{sub sp}), softness parameter and some other physicochemical characteristics were significantly correlated with EC{sub 50}s of metals to C. subglobosa. The reproducibility of toxicity test was determined using 12 reference toxicants. The coefficient of variability of the EC{sub 50}s ranged from 6.95% to 55.37% and variability was comparable to that noticed for D. magna and other aquatic test models. The study demonstrated the need to include crustacean ostracods in a battery of biotests to detect the presence of hazardous chemicals in soils, sewage sludges, sediments and aquatic systems.

  18. The effects of steady swimming on fish escape performance.

    Science.gov (United States)

    Anwar, Sanam B; Cathcart, Kelsey; Darakananda, Karin; Gaing, Ashley N; Shin, Seo Yim; Vronay, Xena; Wright, Dania N; Ellerby, David J

    2016-06-01

    Escape maneuvers are essential to the survival and fitness of many animals. Escapes are frequently initiated when an animal is already in motion. This may introduce constraints that alter the escape performance. In fish, escape maneuvers and steady, body caudal fin (BCF) swimming are driven by distinct patterns of curvature of the body axis. Pre-existing muscle activity may therefore delay or diminish a response. To quantify the performance consequences of escaping in flow, escape behavior was examined in bluegill sunfish (Lepomis macrochirus) in both still-water and during steady swimming. Escapes executed during swimming were kinematically less variable than those made in still-water. Swimming escapes also had increased response latencies and lower peak velocities and accelerations than those made in still-water. Performance was also lower for escapes made up rather than down-stream, and a preference for down-stream escapes may be associated with maximizing performance. The constraints imposed by pre-existing motion and flow, therefore, have the potential to shape predator-prey interactions under field conditions by shifting the optimal strategies for both predators and prey. PMID:27161016

  19. Acute toxicity of metals and reference toxicants to a freshwater ostracod, Cypris subglobosa Sowerby, 1840 and correlation to EC(50) values of other test models.

    Science.gov (United States)

    Khangarot, B S; Das, Sangita

    2009-12-30

    The ostracod Cypris subglobosa Sowerby, 1840 static bioassay test on the basis of a 48h of 50% of immobilization (EC(50)) has been used to measure the toxicity of 36 metals and metalloids and 12 reference toxicants. Among the 36 metals and metalloids, osmium (Os) was found to be the most toxic in the test while boron (B), the least toxic. The EC(50) values of this study revealed positive linear relationship with the established test models of cladoceran (Daphnia magna), sludge worm (Tubifex tubifex), chironomid larvae (Chironomus tentans), protozoan (Tetrahymena pyriformis), fathead minnow (Pimephales promelas), bluegill sunfish (Lepomis macrochirus), and aquatic macrophyte duckweed (Lemna minor). Correlation coefficients (r(2)) for 17 physicochemical properties of metals or metal ions and EC(50)s (as pM) were examined by linear regression analysis. The electronegativity, ionization potential, melting point, solubility product of metal sulfides (pK(sp)), softness parameter and some other physicochemical characteristics were significantly correlated with EC(50)s of metals to C. subglobosa. The reproducibility of toxicity test was determined using 12 reference toxicants. The coefficient of variability of the EC(50)s ranged from 6.95% to 55.37% and variability was comparable to that noticed for D. magna and other aquatic test models. The study demonstrated the need to include crustacean ostracods in a battery of biotests to detect the presence of hazardous chemicals in soils, sewage sludges, sediments and aquatic systems. PMID:19683870

  20. Acute toxicity of metals and reference toxicants to a freshwater ostracod, Cypris subglobosa Sowerby, 1840 and correlation to EC50 values of other test models

    International Nuclear Information System (INIS)

    The ostracod Cypris subglobosa Sowerby, 1840 static bioassay test on the basis of a 48 h of 50% of immobilization (EC50) has been used to measure the toxicity of 36 metals and metalloids and 12 reference toxicants. Among the 36 metals and metalloids, osmium (Os) was found to be the most toxic in the test while boron (B), the least toxic. The EC50 values of this study revealed positive linear relationship with the established test models of cladoceran (Daphnia magna), sludge worm (Tubifex tubifex), chironomid larvae (Chironomus tentans), protozoan (Tetrahymena pyriformis), fathead minnow (Pimephales promelas), bluegill sunfish (Lepomis macrochirus), and aquatic macrophyte duckweed (Lemna minor). Correlation coefficients (r2) for 17 physicochemical properties of metals or metal ions and EC50s (as pM) were examined by linear regression analysis. The electronegativity, ionization potential, melting point, solubility product of metal sulfides (pKsp), softness parameter and some other physicochemical characteristics were significantly correlated with EC50s of metals to C. subglobosa. The reproducibility of toxicity test was determined using 12 reference toxicants. The coefficient of variability of the EC50s ranged from 6.95% to 55.37% and variability was comparable to that noticed for D. magna and other aquatic test models. The study demonstrated the need to include crustacean ostracods in a battery of biotests to detect the presence of hazardous chemicals in soils, sewage sludges, sediments and aquatic systems.

  1. Multidimensional analysis of suction feeding performance in fishes: fluid speed, acceleration, strike accuracy and the ingested volume of water.

    Science.gov (United States)

    Higham, Timothy E; Day, Steven W; Wainwright, Peter C

    2006-07-01

    Suction feeding fish draw prey into the mouth using a flow field that they generate external to the head. In this paper we present a multidimensional perspective on suction feeding performance that we illustrate in a comparative analysis of suction feeding ability in two members of Centrarchidae, the largemouth bass (Micropterus salmoides) and bluegill sunfish (Lepomis macrochirus). We present the first direct measurements of maximum fluid speed capacity, and we use this to calculate local fluid acceleration and volumetric flow rate. We also calculated the ingested volume and a novel metric of strike accuracy. In addition, we quantified for each species the effects of gape magnitude, time to peak gape, and swimming speed on features of the ingested volume of water. Digital particle image velocimetry (DPIV) and high-speed video were used to measure the flow in front of the mouths of three fish from each species in conjunction with a vertical laser sheet positioned on the mid-sagittal plane of the fish. From this we quantified the maximum fluid speed (in the earthbound and fish's frame of reference), acceleration and ingested volume. Our method for determining strike accuracy involved quantifying the location of the prey relative to the center of the parcel of ingested water. Bluegill sunfish generated higher fluid speeds in the earthbound frame of reference, accelerated the fluid faster, and were more accurate than largemouth bass. However, largemouth bass ingested a larger volume of water and generated a higher volumetric flow rate than bluegill sunfish. In addition, because largemouth bass swam faster during prey capture, they generated higher fluid speeds in the fish's frame of reference. Thus, while bluegill can exert higher drag forces on stationary prey items, largemouth bass more quickly close the distance between themselves and prey. The ingested volume and volumetric flow rate significantly increased as gape increased for both species, while time to peak

  2. 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. PMID:26052633

  3. Energetic limitations on suction feeding performance in centrarchid fishes.

    Science.gov (United States)

    Carroll, Andrew M; Wainwright, Peter C

    2009-10-01

    Energetic analysis of ecologically relevant behaviors can be useful because animals are energetically limited by available muscle mass. In this study we hypothesized that two major determinants of suction feeding performance, the magnitudes of buccal volumetric expansion and subambient buccal pressure, would be correlated with, and limited by, available muscle mass. At least four individuals of three centrarchid species were studied: largemouth bass (Micropterus salmoides), bluegill (Lepomis macrochirus) and green sunfish (Lepomis cyanellus). Buccal pressure was measured directly via cannulation of the buccal cavity with a catheter-tipped pressure transducer. Buccal expansion was estimated from lateral high-speed video (500 or 1000 Hz) sequences and published data on internal kinematics of largemouth bass. These estimates were calibrated from silicone casts made of the buccal cavity post-mortem. Estimated work and power were found to be significantly correlated with muscle mass over all individuals. The slopes of these relationships, estimates of mass-specific muscle work and power, were found to be 11+/-2 J kg(-1) and 300+/-75 W kg(-1), respectively. These estimates are consistent with observations made of in vivo and in vitro muscle use and with digital particle image velocimetry measurements of water flow in feeding centrarchids. A direct trade-off between mean pressure and change in volume was observed, when the latter was normalized to muscle mass. We conclude that available muscle mass may be a useful metric of suction feeding performance, and that the ratio of muscle mass to buccal volume may be a useful predictor of subambient buccal pressure magnitude. PMID:19801429

  4. 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. PMID:26807984

  5. Predicting propulsive forces using distributed sensors in a compliant, high DOF, robotic fin.

    Science.gov (United States)

    Kahn, Jeff C; Peretz, David J; Tangorra, James L

    2015-06-01

    Engineered robotic fins have adapted principles of propulsion from bony-finned fish, using spatially-varying compliance and complex kinematics to produce and control the fin's propulsive force through time. While methods of force production are well understood, few models exist to predict the propulsive forces of a compliant, high degree of freedom, robotic fin as it moves through fluid. Inspired by evidence that the bluegill sunfish (Lepomis macrochirus) has bending sensation in its pectoral fins, the objective of this study is to understand how sensors distributed within a compliant robotic fin can be used to estimate and predict the fin's propulsive force. A biorobotic model of a bluegill sunfish pectoral fin was instrumented with pressure and bending sensors at multiple locations. Experiments with the robotic fin were executed that varied the swimming gait, flapping frequency, stroke phase, and fin stiffness to understand the forces and sensory measures that occur during swimming. A convolution-based, multi-input-single-output (MISO) model was selected to model and study the relationships between sensory data and propulsive force. Subsets of sensory data were studied to determine which sensor modalities and sensor placement locations resulted in the best force predictions. The propulsive forces of the fin were accurately predicted using the linear MISO model on intrinsic sensory data. Bending sensation was more effective than pressure sensation for predicting propulsive forces, and the importance of bending sensation was consistent with several results in biology and engineering studies. It was important to have a spatial distribution of sensors and multiple sensory modalities in order to predict forces across large changes to dynamics. The relationship between propulsive forces and intrinsic sensory measures is complex, and good models should allow for temporal lags between forces and sensory data, changes to the model within a fin stroke, and changes to the

  6. Interspecific and environment-induced variation in hypoxia tolerance in sunfish.

    Science.gov (United States)

    Borowiec, Brittney G; Crans, Kyle D; Khajali, Fariborz; Pranckevicius, Nicole A; Young, Alexander; Scott, Graham R

    2016-08-01

    Hypoxia tolerance is a plastic trait, and can vary between species. We compared hypoxia tolerance (hypoxic loss of equilibrium, LOE, and critical O2 tension, Pcrit) and traits that dictate O2 transport and metabolism in pumpkinseed (Lepomis gibbosus), bluegill (L. macrochirus), and the naturally occurring hybrid in different acclimation environments (wild versus lab-acclimated fish) and at different temperatures. Wild fish generally had lower Pcrit and lower PO2 at LOE in progressive hypoxia than lab-acclimated fish, but time to LOE in sustained hypoxia (PO2 of 2kPa) did not vary between environments. Wild fish also had greater gill surface area and higher haematocrit, suggesting that increased O2 transport capacity underlies the environmental variation in Pcrit. Metabolic (lactate dehydrogenase, LDH; pyruvate kinase, PK; citrate synthase; cytochrome c oxidase) and antioxidant (catalase and superoxide dismutase) enzyme activities varied appreciably between environments. Wild fish had higher protein contents across tissues and higher activities of LDH in heart, PK in brain, and catalase in brain, liver, and skeletal muscle. Otherwise, wild fish had lower activities for most enzymes. Warming temperature from 15 to 25°C increased O2 consumption rate, Pcrit, PO2 at LOE, and haemoglobin-O2 affinity, and decreased time to LOE, but pumpkinseed had ≥2-fold longer time to LOE than bluegill and hybrids across this temperature range. This was associated with higher LDH activities in the heart and muscle, and lower or similar antioxidant enzyme activities in several tissues. However, the greater hypoxia tolerance of pumpkinseed collapsed at 28°C, demonstrating that the interactive effects of hypoxia and warming temperature can differ between species. Overall, distinct mechanisms appear to underpin interspecific and environment-induced variation in hypoxia tolerance in sunfish. PMID:27085372

  7. 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.

  8. 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

  9. Investigation of Fish Caudal Fin Locomotion Using a Bio-inspired Robotic Model

    Directory of Open Access Journals (Sweden)

    Ziyu Ren

    2016-05-01

    Full Text Available Due to its advantages of realizing repeatable experiments, collecting data and isolating key factors, the bio-robotic model is becoming increasingly important in the study of biomechanics. The caudal fin of fish has long been understood to be central to propulsion performance, yet its contribution to manoeuverability, especially for homocercal caudal fin, has not been studied in depth. In the research outlined in this paper, we designed and fabricated a robotic caudal fin to mimic the morphology and the three-dimensional (3D locomotion of the tail of the Bluegill Sunfish (Lepomis macrochirus. We applied heave and pitch motions to the robot to model the movement of the caudal peduncle of its biological counterpart. Force measurements and 2D and 3D digital particle image velocimetry were then conducted under different movement patterns and flow speeds. From the force data, we found the addition of the 3D caudal fin locomotion significantly enhanced the lift force magnitude. The phase difference between the caudal fin ray and peduncle motion was a key factor in simultaneously controlling the thrust and lift. The increased flow speed had a negative impact on the generation of lift force. From the average 2D velocity field, we observed that the vortex wake directed water both axially and vertically, and formed a jet like structure with notable wake velocity. The 3D instantaneous velocity field at 0.6 T indicated the 3D motion of the caudal fin may result in asymmetry wake flow patterns relative to the mid-sagittal plane and change the heading direction of the shedding vortexes. Based on these results, we hypothesized that live fish may actively tune the movement between the caudal fin rays and the peduncle to change the wake structure behind the tail and hence obtain different thrust and lift forces, which contributes to its high manoeuvrability.

  10. Hydrodynamics of a robotic fish tail: effects of the caudal peduncle, fin ray motions and the flow speed.

    Science.gov (United States)

    Ren, Ziyu; Yang, Xingbang; Wang, Tianmiao; Wen, Li

    2016-02-01

    Recent advances in understanding fish locomotion with robotic devices have included the use of biomimetic flapping based and fin undulatory locomotion based robots, treating two locomotions separately from each other. However, in most fish species, patterns of active movements of fins occur in concert with the body undulatory deformation during swimming. In this paper, we describe a biomimetic robotic caudal fin programmed with individually actuated fin rays to mimic the fin motion of the Bluegill Sunfish (Lepomis macrochirus) and coupled with heave and pitch oscillatory motions adding to the robot to mimic the peduncle motion which is derived from the undulatory fish body. Multiple-axis force and digital particle image velocimetry (DPIV) experiments from both the vertical and horizontal planes behind the robotic model were conducted under different motion programs and flow speeds. We found that both mean thrust and lift could be altered by changing the phase difference (φ) from 0° to 360° between the robotic caudal peduncle and the fin ray motion (spanning from 3 mN to 124 mN). Notably, DPIV results demonstrated that the caudal fin generated multiple wake flow patterns in both the vertical and horizontal planes by varying φ. Vortex jet angle and thrust impulse also varied significantly both in these two planes. In addition, the vortex shedding position along the spanwise tail direction could be shifted around the mid-sagittal position between the upper and lower lobes by changing the phase difference. We hypothesize that the fish caudal fin may serve as a flexible vectoring propeller during swimming and may be critical for the high maneuverability of fish. PMID:26855405

  11. 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.

  12. Relating fish health and reproductive metrics to contaminant bioaccumulation at the Tennessee Valley Authority Kingston coal ash spill site.

    Science.gov (United States)

    Pracheil, Brenda M; Marshall Adams, S; Bevelhimer, Mark S; Fortner, Allison M; Greeley, Mark S; Murphy, Cheryl A; Mathews, Teresa J; Peterson, Mark J

    2016-08-01

    A 4.1 million m(3) coal ash release into the Emory and Clinch rivers in December 2008 at the Tennessee Valley Authority's Kingston Fossil Plant in east Tennessee, USA, prompted a long-term, large-scale biological monitoring effort to determine if there are chronic effects of this spill on resident biota. Because of the magnitude of the ash spill and the potential for exposure to coal ash-associated contaminants [e.g., selenium (Se), arsenic (As), and mercury (Hg)] which are bioaccumulative and may present human and ecological risks, an integrative, bioindicator approach was used. Three species of fish were monitored-bluegill (Lepomis macrochirus), redear sunfish (L. microlophus), and largemouth bass (Micropterus salmoides)-at ash-affected and reference sites annually for 5 years following the spill. On the same individual fish, contaminant burdens were measured in various tissues, blood chemistry parameters as metrics of fish health, and various condition and reproduction indices. A multivariate statistical approach was then used to evaluate relationships between contaminant bioaccumulation and fish metrics to assess the chronic, sub-lethal effects of exposure to the complex mixture of coal ash-associated contaminants at and around the ash spill site. This study suggests that while fish tissue concentrations of some ash-associated contaminants are elevated at the spill site, there was no consistent evidence of compromised fish health linked with the spill. Further, although relationships between elevated fillet burdens of ash-associated contaminants and some fish metrics were found, these relationships were not indicative of exposure to coal ash or spill sites. The present study adds to the weight of evidence from prior studies suggesting that fish populations have not incurred significant biological effects from spilled ash at this site: findings that are relevant to the current national discussions on the safe disposal of coal ash waste. PMID:27154845

  13. 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: 0.678, year: 2014

  14. Freshwater fishes of Bontebok National Park

    Directory of Open Access Journals (Sweden)

    I.A. Russell

    2001-08-01

    Full Text Available Fish assemblages were sampled at six sites in the Breede River in the Bontebok National Park during 1999 and 2000. A total of 380 fish from 12 species was recorded. Indigenous fish collected included one freshwater species (Barbus andrewi, two catodromous species (Anguilla mossambica, Myxus capensis. and three estuarine species (Gilchris- tella aestuaria, Monodactylusfalciformis, Mugil cephalus. Four of the species recorded were aliens (Tinea tinea, Lepomis macrochirus, Micropterus salmoides, Micropterus dolomieu and two species translocated from other South African rivers (Tilapia sparrmanii, Clarias gariepinus. A further two indigenous species (Sandelia capensis, Pseudobarbus biirchelli could potentially occur within the park, though the high abundance of alien predators means that there is little chance for recolonisation from tributaries higher in the Breede River system. There is little opportunity to meaningfully conserve most indigenous freshwater fish in Bontebok National Park.

  15. [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. PMID:25966587

  16. Bioavailability of trace metals to green sunfish (Lepomis cyanellus) exposed to suspended sediments from sites on the Upper Mississippi River

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — A unique laboratory exposure system was used in applying environmentally relevant conditions (river traffic simulations) and environmentally relevant sediment...

  17. 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.

  18. Environmental mercury concentrations in cultured low-trophic-level fish using food waste-based diets.

    Science.gov (United States)

    Cheng, Zhang; Mo, Wing Yin; Man, Yu Bon; Lam, Cheung Lung; Choi, Wai Ming; Nie, Xiang Ping; Liu, Yi Hui; Wong, Ming Hung

    2015-01-01

    In this study, different types of food wastes were used as the major source of protein to replace the fish meal in fish feeds to produce quality fish (polyculture of different freshwater fish). During October 2011-April 2012, the concentrations of Hg in water, suspended particulate matter, and sediment of the three experimental fish ponds located in Sha Tau Kok Organic Farm were monitored, and the results were similar to or lower than those detected in commercial fish ponds around the Pearl River Delta (PRD) region (by comparing data of previous and present studies). Health risk assessments indicated that human consumption of grass carp (Ctenopharyngodon idellus), a herbivore which fed food waste feed pellets would be safer than other fish species: mud carp (Cirrhina molitorella), bighead carp (Hypophthalmichthys nobilis), and largemouth bass (Lepomis macrochirus). Due to the lower species diversity and substantially shorter food chains of the polyculture system consisting of only three fish species, the extent of Hg biomagnification was significantly lower than other polyculture ponds around PRD. Furthermore, the use of food waste instead of fish meal (mainly consisted of contaminated trash fish) further reduced the mercury accumulation in the cultured fish. PMID:25087497

  19. Impingement dynamics and age and growth of selected species at Lake Dardanelle: a southcentral reservoir

    International Nuclear Information System (INIS)

    Impingement data collected between 1974 and 1979 was analyzed and compared with four years of data from Arkansas Nuclear One located on Lake Dardanelle. Dorosoma petenense, D. cepedianum, Ictalurus punctatus, Lepomis macrochirus, and several other recreationally or ecologically important species commonly found on the intake screen were chosen for comparison. Weekly natural log transformed impingement estimates were plotted, and yearly impingement estimates were determined over the five year period. An analysis of variance on the transformed weekly estimates of eight species of fish indicated the significance of temperature on impingement for seven species. Yearly impingement of D. petenense was found to be correlated with the weekly average minimum water temperature of the reservoir for all years except 1978. Based on impingement monitoring results and weekly average water temperatures, the lower lethal temperature theshold was determined to be between 3.3 and 5.50C for D. petenense and 0 and 0.50C for D. cepedianum. Impingement of D. petenense decreased significantly when the water temperatures dropped below the lower threshold temperature. Results of the impingement analysis were compared and contrasted with age and growth studies in the reservoir

  20. 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.

  1. Evaluation of the resident-species procedure for developing site-specific water quality criteria for copper in Blaine Creek, Kentucky

    International Nuclear Information System (INIS)

    Acute toxicity tests were performed on each of nine different organisms in Blaine Creek (Lawrence County, KY) water to determine 48-h LC50 values for copper (Cu). Blaine Creek is the receiving stream for Kentucky Power Company's Big Sandy Plant fly-ash pond discharge. Selection of the nine tested species and integration of the results were based on the US Environmental Protection Agency's (EPA's) resident-species procedure. The following LC50 (μg Cu/L) values were obtained: Daphnia pulex 37; Physella sp. 109; Isonychia bicolor 223; Pimephales promelas 284; Stenonema sp. 453; Eurycea bislineata 1,120; Chironomus riparius 1,170; Orconectes sp. 2,370; Lepomis macrochirus 4,300. A final acute value (FAV) of 10.1 μg Cu/L was derived using the Blaine Creek database, which is lower than the EPA's national FAV. The differences in FAVs were due to the effect of database size, not differences in the relative sensitivity of test organisms. The findings provide caution for dischargers who may choose to use the resident-species procedure for future site-specific water-quality-criteria demonstrations. The resident-species procedure, because of the inherent conservative bias of the calculation process, tends to produce more stringent criteria when used on a site-specific basis. A modified recalculation procedure, in conduction with site-specific metal bioavailability data, was judged to be the most appropriate method for deriving site-specific Cu criteria for Blaine Creek

  2. 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: 0.577, year: 2014

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

    International Nuclear Information System (INIS)

    The rates of accumulation and subsequent loss of stable cesium (133Cs) by organisms at different trophic levels within plankton-based and periphyton-based food chains were measured following the addition of 133Cs into a small reservoir near Aiken, South Carolina, USA. An uptake parameter u (L kg-1 d-1 dry mass) and a loss rate parameter k (d-1) were estimated for each organism using time-series measurements of 133Cs concentrations in water and biota, and these parameters were used to estimate maximum concentrations, times to maximum concentrations, and concentration ratios (Cr). The maximum 133Cs 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 Cr based on dry mass for plankton and C. punctipennis were 1220 L kg-1 and 5570 L kg-1, respectively, and were less than the Cr of 8630 L kg-1 for periphyton and 47,700 L kg-1 for H. trivolvis. Although the Cr differed between plankton-based and periphyton-based food chains, they displayed similar levels of biomagnification. Biomagnification was also indicated for fish where the Cr for the mostly nonpiscivorous L. macrochirus of 22,600 L kg-1 was three times less than that for mostly piscivorous M. salmoides of 71,500 L kg-1. Although the Cr for M. salmoides was greater than those for periphyton and H. trivolvis, the maximum 133Cs concentrations for periphyton and H. trivolvis were greater than that for M. salmoides. - Research highlights: → A simple uptake and loss model described the Cs dynamics in all the various biota. → Concentrations of Cs were greater in periphyton than in plankton. → Biota other than fish demonstrated the greatest maximum Cs concentrations. → Concentration ratios were generally consisted

  4. United States high-altitude test experiences. A review emphasizing the impact on the environment. [Checkmate, Bluegill, Kingfish and Tightrope events

    Energy Technology Data Exchange (ETDEWEB)

    Hoerlin, H.

    1976-06-01

    The US high-altitude nuclear explosions of the 1955-1962 period are listed chronologically; dates, locations, and yields are given. The major physical phases of the interactions of the weapon outputs with the atmosphere are described, such as the formation of fireballs at the low high-altitudes and the partition of energies and their distribution over very large spaces at the higher high-altitudes. The effects of these explosions on the normal activities of populations and the protective measures taken are documented. Many scientific observations, together with their significance and values, are reviewed. 109 refs.

  5. 76 FR 14351 - Proposed Withdrawal of Certain Federal Aquatic Life Water Quality Criteria Applicable to Wisconsin

    Science.gov (United States)

    2011-03-16

    ...--Acute Copper Criteria Equation EPA criteria maximum concentration Wisconsin acute toxicity ( g/L... inclusion of additional data on three species (Daphnia magna, rainbow trout, and bluegill) that were not... (Daphnia magna, rainbow trout, and bluegill) that were not included in EPA's 1985 slope calculation used...

  6. 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

  7. The role of environmental contaminants in the prevalence of fish infected with a wading bird parasite (Eustronglides ignotus)

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Northern Florida Eustrongylid larvae were found in 66 fish from 5 of 9 the sites (Table 2). Four species Gambusia holbrooki, Heterandria formosa, Lepomis gulosus,...

  8. TOXICITY OF RESIDUAL CHLORINE COMPOUNDS TO AQUATIC ORGANISMS

    Science.gov (United States)

    Laboratory studies on the acute and chronic toxicity of chlorine and inorganic chloramines to trout, salmon, minnows, bullhead, largemouth bass, and bluegill were conducted. Acute toxicity under continuous and intermittent patterns of exposure as well as behavioral, reproduction,...

  9. Fishery Dynamics of Macrophyte-dominated Banks Lake National Wildlife Refuge, Georgia

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This paper summarizes fish assemblage and sportfish dynamics including bluegill and largemouth bass from 1992 to 2003 on Banks Lake National Wildlife Refuge. Banks...

  10. Annual Project Report, 1978 : Fishery Management Program

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Fourteen miles of shoreline are open to surf fishing on St. Vincent National Wildlife Refuge. Freshwater fishing for largemouth bass, bluegill, and redear sunfish...

  11. Mercury and Selenium Concentrations in Fishes of the St. Vincent National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — From February 16 to May 6, 1988, sixteen largemouth bass, fifteen bluegill, and thirteen brown bullhead, were collected from three fresh water ponds at St. Vincent...

  12. 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

  13. A Dynamic Recommender System for Improved Web Usage Mining and CRM Using Swarm Intelligence

    Science.gov (United States)

    Alphy, Anna; Prabakaran, S.

    2015-01-01

    In modern days, to enrich e-business, the websites are personalized for each user by understanding their interests and behavior. The main challenges of online usage data are information overload and their dynamic nature. In this paper, to address these issues, a WebBluegillRecom-annealing dynamic recommender system that uses web usage mining techniques in tandem with software agents developed for providing dynamic recommendations to users that can be used for customizing a website is proposed. The proposed WebBluegillRecom-annealing dynamic recommender uses swarm intelligence from the foraging behavior of a bluegill fish. It overcomes the information overload by handling dynamic behaviors of users. Our dynamic recommender system was compared against traditional collaborative filtering systems. The results show that the proposed system has higher precision, coverage, F1 measure, and scalability than the traditional collaborative filtering systems. Moreover, the recommendations given by our system overcome the overspecialization problem by including variety in recommendations. PMID:26229978

  14. Effect of block net use and time of sampling on backpack electrofishing catches in three Kansas reservoirs

    Science.gov (United States)

    Schoenebeck, C.W.; Strakosh, T.R.; Guy, C.S.

    2005-01-01

    Using backpack electrofishing in three Kansas reservoirs, we investigated the need for block nets when estimating density (fish/ha) and species diversity and determined whether time of sampling affected catch rates (fish/h) of age-0 largemouth bass Micropterus salmoides and age-0 Lepomis spp. and species diversity. Block nets were used to enclose or buoys were used to mark the boundaries of 149 m2 of reservoir surface area. Species richness, diversity, and density of age-0 largemouth bass and Lepomis spp. did not differ significantly between areas enclosed with block nets and areas marked with buoys, but species richness, diversity, and catch rates differed significantly between day and night sampling. Age-0 largemouth bass and Lepomis spp. catch rates, species richness, and species diversity were all significantly higher during night sampling. Our results indicate that use of block nets may not be necessary to estimate age-0 largemouth bass and Lepomis spp. densities, species richness, or diversity in reservoir littoral areas. We recommend night sampling because of significantly higher catch rates and better representation of the littoral fish assemblage. ?? Copyright by the American Fisheries Society 2005.

  15. EFFECTS OF EXPOSURE TO HEAVY METALS ON SELECTED FRESHWATER FISH. (TOXICITY OF COPPER, CADMIUM, CHROMIUM AND LEAD TO EGGS AND FRY OF SEVEN FISH SPECIES.)

    Science.gov (United States)

    Embryo and larvae of rainbow trout, lake trout, channel catfish, bluegill, white sucker, northern pike, and walleye were exposed for 60 days after hatch to lead and chromium in soft water. Brook trout, channel catfish, and walleyes were also exposed for 60 days after hatch to cop...

  16. DISTRIBUTION OF MERCURY IN THE TISSUES OF FIVE SPECIES OF FRESHWATER FISH FROM LAKE MEAD, USA

    Science.gov (United States)

    Total mercury (Hg) concentrations were determined in seven tissues (skeletal muscle, liver, blood, gonad, brain, gill, and heart) of 59 striped bass and four tissues (muscle, liver, blood, and gonad) of 69 largemouth bass, 76 channel catfish, 12 bluegill, and 22 blue tila...

  17. 21 CFR 529.1030 - Formalin.

    Science.gov (United States)

    2010-04-01

    ... control of fungi of the family Saprolegniaceae. (2) Amount. The drug concentrations required are as... FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS..., largemouth bass, and bluegill. (ii) Select finfish eggs. For control of fungi of the family...

  18. 76 FR 57646 - Final Withdrawal of Certain Federal Aquatic Life Water Quality Criteria Applicable to Wisconsin

    Science.gov (United States)

    2011-09-16

    ... 2--Acute Copper Criteria Equation EPA criteria maximum concentration Wisconsin acute toxicity... Copper Criteria Equation EPA criterion continuous Wisconsin chronic toxicity criteria concentration ( g/L... species (Daphnia magna, rainbow trout, and bluegill) that were not included in the EPA's 1985...

  19. Inter-laboratory comparison of cell lines for susceptibility to three viruses: VHSV, IHNV and IPNV

    DEFF Research Database (Denmark)

    Lorenzen, Ellen; Carstensen, Bendix; Olesen, Niels Jørgen

    1999-01-01

    pancreatic necrosis Virus (IPNV), and the cell lines derived from bluegill fry (BF-2), chinook salmon embryo (CHSE-214), epithelioma papulosum cyprini (EPC), fathead minnow (FHM) and rainbow trout gonad (RTG-2). The results showed that for isolation of VHSV, BF-2 and RTG-2 cells performed equally well and...

  20. Population size structure of non-native fishes along longitudinal gradients in a highly regulated Mediterranean basin.

    OpenAIRE

    Fátima Amat-Trigo

    2015-01-01

    Population size structure can provide insights in species-specific knowledge and fish management. The purpose of the present study is to assess the influence of hydrological flow variability along the longitudinal gradient in the population size structure metrics of three non-native fish species widely distributed in the Iberian Peninsula, Alburnus alburnus L., Lepomis gibbosus L. and Gobio lozanoi Doadrio & Madeira, 2004. We analysed populations at site level (29 sampling localities in fluvi...

  1. 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

    OpenAIRE

    Gorgonio Ruiz-Campos; Salvador Contreras-Balderas; Asunción Andreu-Soler; Alejandro Varela-Romero; Ernesto Campos

    2012-01-01

    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 (Cyp...

  2. 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.

  3. A minimally invasive method of piscine tissue collection and an analysis of long-term field-storage conditions for samples

    OpenAIRE

    Smalley John V; Campanella James J

    2006-01-01

    Abstract Background The acquisition of high-quality DNA for use in phylogenetic and molecular population genetic studies is a primary concern for evolutionary and genetic researchers. Many non-destructive DNA sampling methods have been developed and are used with a variety of taxa in applications ranging from genetic stock assessment to molecular forensics. Results The authors have developed a field sampling method for obtaining high-quality DNA from sunfish (Lepomis) and other freshwater fis...

  4. STRUCTURE, GROWTH AND MORPHOLOGY OF FISH POPULATIONS FROM GRAVEL-PIT VUKOVINA

    OpenAIRE

    Ivan Jakovlić; Tomislav Treer

    2001-01-01

    After the structure of fish populations from gravel-pit Vukovina was determined, those populations were checked for 10 morphometric and 4 meristic parameters, as well as for length-mass relationship. For chub (Leuciscus cephalus) and pumpkinseed (Lepomis gibbosus) some meristic characters expressed the values beyond those mentioned in the standard key for the freshwater fish species determination. When compared to other locations, length-mass relationship and condition factor (CF) were signif...

  5. Independently evolved upper jaw protrusion mechanisms show convergent hydrodynamic function in teleost fishes.

    Science.gov (United States)

    Staab, Katie Lynn; Holzman, Roi; Hernandez, L Patricia; Wainwright, Peter C

    2012-05-01

    A protrusible upper jaw has independently evolved multiple times within teleosts and has been implicated in the success of two groups in particular: Acanthomorpha and Cypriniformes. We use digital particle image velocimetry (DPIV) to compare suction feeding flow dynamics in a representative of each of these clades: goldfish and bluegill. Using DPIV, we contrast the spatial pattern of flow, the temporal relationship between flow and head kinematics, and the contribution of jaw protrusion to the forces exerted on prey. As expected, the spatial patterns of flow were similar in the two species. However, goldfish were slower to reach maximal kinematic excursions, and were more flexible in the relative timing of jaw protrusion, other jaw movements and suction flows. Goldfish were also able to sustain flow speeds for a prolonged period of time as compared with bluegill, in part because goldfish generate lower peak flow speeds. In both species, jaw protrusion increased the force exerted on the prey. However, slower jaw protrusion in goldfish resulted in less augmentation of suction forces. This difference in force exerted on prey corresponds with differences in trophic niches and feeding behavior of the two species. The bluegill uses powerful suction to capture insect larvae whereas the goldfish uses winnowing to sort through detritus and sediment. The kinethmoid of goldfish may permit jaw protrusion that is independent of lower jaw movement, which could explain the ability of goldfish to decouple suction flows (due to buccal expansion) from upper jaw protrusion. Nevertheless, our results show that jaw protrusion allows both species to augment the force exerted on prey, suggesting that this is a fundamental benefit of jaw protrusion to suction feeders. PMID:22496281

  6. Trophic structure and metal bioaccumulation differences in multiple fish species exposed to coal ash-associated metals

    Energy Technology Data Exchange (ETDEWEB)

    Otter, Ryan [Middle Tennessee State University; Bailey, Frank [Middle Tennessee State University; Fortner, Allison M [ORNL; Adams, Marshall [ORNL

    2012-01-01

    On December 22, 2008 a dike containing coal fly ash from the Tennessee Valley Authority Kingston Fossil Plant near Kingston Tennessee USA failed and resulted in the largest coal ash spill in U.S. history. Coal ash, the by-product of coal combustion, is known to contain multiple contaminants of concern, including arsenic and selenium. The purpose of this study was to investigate the bioaccumulation of arsenic and selenium and to identify possible differences in trophic dynamics in feral fish at various sites in the vicinity of the Kingston coal ash spill. Elevated levels of arsenic and selenium were observed in various tissues of largemouth bass, white crappie, bluegill and redear sunfish from sites associated with the Kingston coal ash spill. Highest concentrations of selenium were found in redear sunfish with liver concentrations as high as 24.83 mg/kg dry weight and ovary concentrations up to 10.40 mg/kg dry weight at coal ash-associated sites. To help explain the elevated selenium levels observed in redear sunfish, investigations into the gut pH and trophic dynamics of redear sunfish and bluegill were conducted which demonstrated a large difference in the gut physiology between these two species. Redear sunfish stomach and intestinal pH was found to be 1.1 and 0.16 pH units higher than in bluegill, respectively. In addition, fish from coal ash-associated sites showed enrichment of 15N & 13C compared to no ash sites, indicating differences in food web dynamics between sites. These results imply the incorporation of coal ash-associated compounds into local food webs and/or a shift in diet at ash sites compared to the no ash reference sites. Based on these results, further investigation into a broader food web at ash-associated sites is warranted.

  7. Effects of heated effluents on the reproduction of selected species of the Centrarchid family. Progress report, 26 October 1973--25 October 1974

    International Nuclear Information System (INIS)

    The numberof species found in the cooling reservoirs differed. Fourteen species were collected in Pond C and 27 species in Par Pond. Largemouth bass, bluegill, redbreast sunfish and mosquitofish were the only species found to reproduce within Pond C. Largemouth bass and bluegill made up over 95 percent of the fishes in this reservoir. Water temperatures undoubtedly limit the number of species and population sizes in Pond C. Fishes in Pond C often frequented water of a temperature very near to or even above temperatures reported as lethal. Bluegill were found in water ranging from 35 to 410C. Largemouth bass were common in water 32--350C and to 36--370C on one occasion. Evidence is presented which suggests the large population of bass results from the fact that this reservoir has never been available to sport fisherman. The relative abundance of speices followed the same trend between coves each year. Fish kills wereobserved as a result of two different circumstances. At times fish were attracted by cool water and subsequently trapped away from refuge areas and killed by rising temperatures in Pond C. One other type kill occurred when blueback herring migrated from water 160C and swam into water 250C. Tracking of largemouth bass with temperature-sensing ultrasonic transmitters suggests there is a continuous rotation of bass into and out of the thermal mixing area in Par Pond and that there is not a discrete population that has been self-acclimated to the warmer water and forced to remain in the heated effluent. (HLW)

  8. STRUCTURE, GROWTH AND MORPHOLOGY OF FISH POPULATIONS FROM GRAVEL-PIT VUKOVINA

    Directory of Open Access Journals (Sweden)

    Ivan Jakovlić

    2001-12-01

    Full Text Available After the structure of fish populations from gravel-pit Vukovina was determined, those populations were checked for 10 morphometric and 4 meristic parameters, as well as for length-mass relationship. For chub (Leuciscus cephalus and pumpkinseed (Lepomis gibbosus some meristic characters expressed the values beyond those mentioned in the standard key for the freshwater fish species determination. When compared to other locations, length-mass relationship and condition factor (CF were significantly lower for all checked populations. This indicates that gravel-pit Vukovina is extremely oligotrophic and has very poor fish production.

  9. Propagation and isolation of ranaviruses in cell culture

    DEFF Research Database (Denmark)

    Ariel, Ellen; Nicolajsen, Nicole; Christophersen, Maj-Britt;

    2009-01-01

    The optimal in vitro propagation procedure for a panel of ranavirus isolates and the best method for isolation of Epizootic haematopoietic necrosis virus (EHNV) from organ material in cell-culture were investigated. The panel of ranavirus isolates included: Frog virus 3 (FV3), Bohle iridovirus (BIV......), Pike-perch iridovirus (PPIV), European catfish virus (ECV), European sheatfish virus (ESV), EHNV, Doctor fish virus (DFV), Guppy virus 6 (GF6), short-finned eel virus (SERV) and Rana esculenta virus Italy 282/102 (REV 282/102). Each isolate was titrated in five cell lines: bluegill fry (BF-2...

  10. Thermal pollution studies near nuclear power stations in India. Part of a coordinated programme on the physical and biological effects on the environment of cooling systems and thermal discharges from nuclear power plants

    International Nuclear Information System (INIS)

    Thermal stresses caused by higher than ambient temperatures increased the susceptibility of fishes to disease and predation. Examples are given: Bluegill - Predator-prey relationships should be studied as a problem in community relationships. Experiments are reported to find the link between temperature and differential predation rates. In tropical conditions, there is no evidence of any damage to fish life due to warm water releases, however, experiments indicate that conditions in the waters receiving heated effluents are optimal to: proliferation of parasites and pathogens; oxygen supersaturation in outfall; weed growth

  11. Hypoxia tolerance of two centrarchid sunfishes and an introduced cichlid from karstic Everglades wetlands of southern Florida, U.S.A.

    Science.gov (United States)

    Schofield, P.J.; Loftus, W.F.; Brown, M.E.

    2007-01-01

    In this study, the hypoxia tolerance of three Everglades fishes, two native centrarchids (Lepomis gulosus and Lepomis marginatus) and a recently introduced cichlid (Hemichromis letourneuxi), were documented. Aquatic surface respiration (ASR) thresholds were lowest for H. letourneuxi, followed by L. gulosus, then L. marginatus. The ASR thresholds for L. marginatus were within ranges reported for small, freshwater tropical fishes, while those for L. gulosus were similar to swamp-adapted fishes. For H. letourneuxi, ASR thresholds were some of the lowest reported. All three species showed excellent tolerance of low dissolved oxygen levels when allowed access to the surface. When denied surface access, L. marginatus lost equilibrium at a higher oxygen tension than the other species. Overall, although all species easily tolerated hypoxia, H. letourneuxi appeared to be best equipped to deal with hypoxia, followed by L. gulosus, then L. marginatus. Hemichromis letourneuxi also exhibited more aggressive behaviours than the centrarchids. These results suggest that hypoxia is not likely to prevent H. letourneuxi from exploiting the seasonally inundated wetlands of south Florida while expanding its range there.

  12. 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.

  13. Investigations of entrainment mortality among larval and juvenile fishes using a Power Plant Simulator

    International Nuclear Information System (INIS)

    A Power Plant Simulator (PPS) was constructed at the Oak Ridge National Laboratory to examine the component sources of entrainment mortality. This experimental apparatus circulates temperature-controlled water through a closed loop consisting of a pump, a condenser bundle, and vertically adjustable piping. Larval bluegill, channel catfish, carp, largemouth bass, and smallmouth bass and juvenile bluegill and mosquitofish were exposed to different combinations of pump speed and water temperatures in the PPS. Wide differences among species in their sensitivity to pipe and condenser passage were observed. For most of the species tested, short-term conditional mortalities resulting from the physical stresses of pipe and condenser passage increased with ΔT and/or pumping rate. Pump passage was not a major source of physical damage, and no clear relationship was found between pump efficiency and mortality. Susceptibility to physical stresses associated with entrainment was inversely related to the size of the entrained organisms. Delayed mortality frequently occurred among fishes exposed to stresses in the PPS. However, delayed mortality estimates in these experimental groups were significantly greater than corresponding values in handling control groups in only 15 of 64 comparisons. Like short-term mortalities, relatively higher delayed mortalities were often observed for the smaller species tested

  14. Concentration of radionuclides in fresh water fish downstream of Rancho Seco Nuclear Generating Plant

    International Nuclear Information System (INIS)

    Fish were collected for radionuclide analysis over a 5-month period in 1984 from creeks downstream of the Rancho Seco Nuclear Generating Plant, which has been discharging quantities of some fission and activation products to the waterway since 1981. Among the fish, the bluegill was selected for intensive study because it is very territorial and the radionuclide concentrations detected should be representative of the levels in the local environment at the downstream locations sampled. Among the gamma-emitting radionuclides routinely released, only 134Cs and 137Cs were detected in the edible flesh of fish. Concentrations in the flesh of fish decreased with distance from the plant. The relationship between concentration and distance was determined to be exponential. Exponential equations were generated to estimate concentrations in fish at downstream locations where no site-specific information was available. Mean concentrations of 137Cs in bluegill collected during April, May, July and August from specific downstream stations were not significantly different in spite of the release of 131 mCi to the creeks between April and August. The concentrations in fish are not responding to changes in water concentrations brought about by plant discharges. Diet appears to be a more significant factor than size or weight or water concentration in regulating body burdens of 137Cs in these fish

  15. Fish passage through a simulated horizontal bulb turbine pressure regime: A supplement to "Laboratory Studies of the Effects of Pressure and Dissolved Gas Supersaturation on Turbine-Passed Fish"

    Energy Technology Data Exchange (ETDEWEB)

    Abernethy, C. S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Amidan, B. G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Cada, G. F. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2003-07-01

    Migratory and resident fish in the Columbia River Basin are exposed to stresses associated with hydroelectric power production, including pressure changes during turbine passage. The responses of fall chinook salmon and bluegill sunfish to rapid pressure change was investigated at the Pacific Northwest National Laboratory. Previous test series evaluated the effects of passage through a vertical Kaplan turbine under the “worst case” pressure conditions (Abernethy et al. 2001) and under less severe conditions where pressure changes were minimized (Abernethy et al. 2002). For this series of tests, pressure changes were modified to simulate passage through a horizontal bulb turbine, commonly installed at low-head dams. The results were compared to results from previous test series. Tests indicated that for most of the cross-sectional area of a horizontal bulb turbine, pressure changes occurring during turbine passage are not harmful to fall chinook salmon and only minimally harmful to bluegill. However, some areas within a horizontal bulb turbine may have extreme pressure conditions that would be harmful to fish. These scenarios were not tested because they represent a small cross-sectional area of the turbine compared to the centerline pressures scenarios used in these tests.

  16. 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

  17. A digital underwater video camera system for aquatic research in regulated rivers

    Science.gov (United States)

    Martin, Benjamin M.; Irwin, Elise R.

    2010-01-01

    We designed a digital underwater video camera system to monitor nesting centrarchid behavior in the Tallapoosa River, Alabama, 20 km below a peaking hydropower dam with a highly variable flow regime. Major components of the system included a digital video recorder, multiple underwater cameras, and specially fabricated substrate stakes. The innovative design of the substrate stakes allowed us to effectively observe nesting redbreast sunfish Lepomis auritus in a highly regulated river. Substrate stakes, which were constructed for the specific substratum complex (i.e., sand, gravel, and cobble) identified at our study site, were able to withstand a discharge level of approximately 300 m3/s and allowed us to simultaneously record 10 active nests before and during water releases from the dam. We believe our technique will be valuable for other researchers that work in regulated rivers to quantify behavior of aquatic fauna in response to a discharge disturbance.

  18. Protection against heavy metal toxicity by mucous and scales in fish

    Energy Technology Data Exchange (ETDEWEB)

    Coello, W.F.; Khan, M.A.Q. [Univ. of Illinois, Chicago, IL (United States). Dept. of Biological Sciences

    1995-12-31

    Fingerlings of three freshwater fish species showed differences in susceptibility to lethality of 250 mg/L lead suspension or lead nitrate solution in water. Among these the large mouth bass Micropterus salmoides seemed to be more tolerant than green sunfish Lepomis cyanellus and goldfish Carassius auratus. Mucous from large mouth bass, when added to jars containing lead, lowered the toxicity of lead to sunfish and goldfish. Adding scales, especially if these were pretreated with an alkaline solution of cysteine and glycine, made all these species become tolerant to otherwise lethal concentrations of lead nitrate. The scales and mucous together buffered the acidity of lead nitrate and mercuric nitrate solution and sequestered hydrogen ions and lead and mercury from water and then settled to the bottom of jars. Scales of younger fingerling were more efficient than those of older ones.

  19. Protection against heavy metal toxicity by mucus and scales in fish.

    Science.gov (United States)

    Coello, W F; Khan, M A

    1996-03-01

    Fingerlings of three freshwater fish showed differences in susceptibility to lethality of 250 mg/L lead suspension or lead nitrate solution in water. Among these, the largemouth bass (Micropterus salmoides) was more tolerant than green sunfish (Lepomis cyanellus) and goldfish (Carassius auratus). The addition of mucus from largemouth bass, when added to jars containing lead, increased the LT-50 value (time to kill 50% of fingerling exposed to 250 mg/L lead) in green sunfish and goldfish. However, adding scales, especially if the scales were treated with an alkaline solution of cysteine and glycine, made all of these species tolerant to otherwise lethal concentrations of lead or mercury. The scales buffered the pH of lead nitrate solution as well as removed lead (and mercury) from water (by settling down at the bottom after sequestering lead). Scales of younger fingerlings of largemouth bass were more efficient in chelating heavy metals than those of older ones. PMID:8854966

  20. A Biologically Derived Pectoral Fin for Yaw Turn Manoeuvres

    Directory of Open Access Journals (Sweden)

    Jonah R. Gottlieb

    2010-01-01

    Full Text Available A bio-robotic fin has been developed that models the pectoral fin of the bluegill sunfish as the fish turned to avoid an obstacle. This work involved biological studies of the sunfish fin, the development of kinematic models of the motions of the fin's rays, CFD based predictions of the 3D forces and flows created by the fin, and the implementation of simplified models of the fin's kinematics and mechanical properties in a physical model. The resulting robotic fin produced the forces and flows that drove the manoeuvre and had a sufficiently high number of degrees of freedom to create a variety of non-biologically derived motions. The results indicate that for robotic fins to produce a level of performance on par with biological fins, both the kinematics and the mechanical properties of the biological fin must be modelled well.

  1. Synthetic Fuels Program

    International Nuclear Information System (INIS)

    Progress is reported on aquatic transport studies with regard to photolysis of polycyclic compounds in water; volatilization of PAH from water; bioaccumulation of anthracene by fathead minnows; bioaccumulation of polycyclic aromatic hydrocarbons by aquatic invertebrates; bioaccumulation of arylamines by zooplankton; availability of sediment-bound trace metals to bluegill; microbial transformation; transport and transformation of anthracene in natural waters; and microcosm studies. Progress is also reported on acute and chronic aquatic effects; acute and chronic terrestrial effects; leaching and chemical and physical characterization of solid wastes; toxicology of solid wastes; and field site task studies with regard to aquatic transport behavior of trace contaminants in wastewater discharges and airborne contaminants at coking plant field site

  2. Spatial trends and impairment assessment of mercury in sport fish in the Sacramento-San Joaquin Delta watershed

    International Nuclear Information System (INIS)

    A three-year study was conducted to examine mercury in sport fish from the Sacramento-San Joaquin Delta. More than 4000 fish from 31 species were collected and analyzed for total mercury in individual muscle filets. Largemouth bass and striped bass were the most contaminated, averaging 0.40 μg/g, while redear sunfish, bluegill and rainbow trout exhibited the lowest (<0.15 μg/g) concentrations. Spatial variation in mercury was evaluated with an analysis of covariance model, which accounted for variability due to fish size and regional hydrology. Significant regional differences in mercury were apparent in size-standardized largemouth bass, with concentrations on the Cosumnes and Mokelumne rivers significantly higher than the central and western Delta. Significant prey-predator mercury correlations were also apparent, which may explain a significant proportion of the spatial variation in the watershed. - Regional differences in sport fish mercury were found in the Sacramento-San Joaquin Delta.

  3. Comparative toxicity and bioconcentration of nonylphenol in freshwater organisms.

    Science.gov (United States)

    Spehar, Robert L; Brooke, Larry T; Markee, Thomas P; Kahl, Michael D

    2010-09-01

    Degradation of alkylphenol ethoxylates to more persistent alkylphenols such as nonylphenol occurs in wastewater treatment plants where nonylphenol is released to aquatic systems. In this study, acute and chronic tests were conducted to determine the toxicity and bioconcentration of nonylphenol to freshwater organisms for use in deriving national water quality criteria. Acute median effect concentrations (EC50s) based on loss of equilibrium, immobility, and lethality for species representing several taxonomic groups ranged from 21 to 596 microg/L. The EC50s were up to a factor of 2 less than median lethal concentrations (LC50s) and decreased with time over the test periods of 24 to 96 h. In chronic tests, early life stages of rainbow trout were 14 times more sensitive to nonylphenol than in acute tests and approximately 20 times more sensitive than Daphnia magna exposed over their complete life cycle. Comparisons of chronic test endpoints showed that 20% effect concentrations (EC20s), determined by regression testing, and chronic values, determined by hypothesis testing, were similar for both the rainbow trout and Daphnia magna. The lowest mean tissue-effect concentrations of nonylphenol appeared to be greater for the fathead minnow than bluegill, and ranged from approximately 130 to 160 microg/g after 96-h exposure and from approximately 20 to 90 microg/g after 28-d exposure. Mean lipid normalized bioconcentration factors (BCFs) associated with no-effect concentrations were approximately 180 and 50 for the fathead minnow and bluegill, respectively. The present test results suggest that long-term exposures to nonylphenol at concentrations found in some surface waters could adversely impact sensitive components of freshwater communities. PMID:20821669

  4. The pressures of suction feeding: the relation between buccal pressure and induced fluid speed in centrarchid fishes.

    Science.gov (United States)

    Higham, Timothy E; Day, Steven W; Wainwright, Peter C

    2006-09-01

    Suction feeding fish rapidly expand their oral cavity, resulting in a flow of water directed towards the mouth that is accompanied by a drop in pressure inside the buccal cavity. Pressure inside the mouth and fluid speed external to the mouth are understood to be mechanically linked but the relationship between them has never been empirically determined in any suction feeder. We present the first simultaneous measurements of fluid speed and buccal pressure during suction feeding in fishes. Digital particle image velocimetry (DPIV) and high-speed video were used to measure the maximum fluid speed in front of the mouth of four largemouth bass and three bluegill sunfish by positioning a vertical laser sheet on the mid-sagittal plane of the fish. Peak magnitude of pressure inside the buccal cavity was quantified using a transducer positioned within a catheter that opened into the dorsal wall of the buccal cavity. In both species the time of peak pressure preceded the time of peak fluid speed by as much as 42 ms, indicating a role for unsteady flow effects in shaping this relation. We parameterized an existing model of suction feeding to determine whether the relationship between peak pressures and fluid speeds that we observed could be predicted using just a few kinematic variables. The model predicted much higher fluid speeds than we measured at all values of peak pressure and gave a scaling exponent between them (0.51) that was higher than observed (0.36 for largemouth bass, 0.38 for bluegill). The scaling between peak buccal pressure and peak fluid speed at the mouth aperture differed in the two species, supporting the recent conclusion that species morphology affects this relation such that a general pattern may not hold. PMID:16916963

  5. Effects of heated effluents from a nuclear reactor on species diversity, abundance, reproduction, and movement of fish

    International Nuclear Information System (INIS)

    The number of species found in the cooling reservoirs differed. Fourteen species were collected in Pond C and 27 species in Par Pond. Largemouth bass, bluegill, redbreast sunfish and mosquito-fish were the only species found to reproduce within Pond C. Water temperatures undoubtedly limit the number of species and population sizes in Pond C. Bluegill were found in water ranging from 35 to 410C . Largemouth bass were common in water 32-350C and to 36-370C on one occasion. In general, the standing crop of the fishes in Par Pond as determined by cove-rotenone samples were similar to nearby reservoirs in South Carolina and did not differ greatly from ambient waters in 1972. The bass population throughout Par Pond is above that found in other South Carolina reservoirs. Evidence is presented which suggests the large population of bass results from the fact that this reservoir has never been available to sport fishermen. Fish kills were observed as a result of two different circumstances. At times fish were attracted by cool water and subsequently trapped away from refuge areas and killed by rising temperatures in Pond C. One other type kill occurred when blueback herring migrated from water 160C and swam into water 250C. There is a continuous rotation of bass into and out of the thermal mixing area in Par Pond. There is not a discrete population that has been self-acclimated to the warmer water and forced to remain in the heated effluent. (HLW)

  6. Interaction between chlorpyrifos and hepatic microsomal cytochrome P450 enzyme system in fish%毒死蜱与鱼肝微粒体P450的相互作用

    Institute of Scientific and Technical Information of China (English)

    边文杰; 徐燕; 李少南; 朱国念

    2011-01-01

    为了评估毒死蜱对水生生态系统的风险,比较研究了毒死蜱对斑马鱼、麦穗鱼及太阳鱼的急性毒性,3种鱼肝微粒体P450酶系对毒死蜱的脱硫转化作用及毒死蜱对肝微粒体P450酶系的影响.结果表明,毒死蜱对斑马鱼、麦穗鱼及太阳鱼的96 h-LC50分别为1.94,0.0273,0.0681 mg·L-1.3种鱼肝微粒体P450酶系对毒死蜱代谢的Vmax/Km值分别为:1.67×104,5.00×104,2.00× 104,即代谢能力大小为麦穗鱼>太阳鱼>斑马鱼,与急性毒性试验结果相吻合,从而P450酶系的脱硫转化活性可以一定程度上解释毒死蜱对3种鱼的毒性差异.试验浓度毒死蜱对3种鱼的P450酶系的影响不显著.%Acute toxicity of chlorpyrifos to Danio rerio, Pseudorasboraparva, and Lepomis gibbosus, oxidative activation of chlorpyrifos catalyzed by hepatic microsomal cytochrome P450 system, and influence of chlorpyrifos to the P450 system were studied to evaluate the risk of chlorpyrifos on ecology system. 96 h LC50 of chlorpyrifos to the Dani-o rerio, the Pseudorasbora parva, and the Lepomis gibbosus was measured to be 1. 94, 0. 0273, 0. 0681 mg·L-1, respectively. The Vmax/Km of chlorpyrifos oxidation catalyzed by P450 system was measured to be 1. 67 × 104 , 5. 00 × 104, 2. 00 × 104 , respectively, indicating that the oxidative metabolism capacity of the P450 system was the highest in Pseudorasbora parva and the lowest in Danio rerio, which matched the results of acute toxicity tests. The influence of chlorpyrifos to the P450 system was not obvious.

  7. RESEARCH ABOUT ICHTHYOPARASITOFAUNA OF BANAT REGION

    Directory of Open Access Journals (Sweden)

    C.Cojocaru

    2003-01-01

    Full Text Available During the years 2001 and 2002 were parasitologically examined 16 species of fishes (Cyprinus carpio, Carassius auratus gibelio, Scardinius erythrophthalmus, Rutilus rutilus, Abramis brama danubii, Alburnus alburnus, Gobio spp., Leuciscus cephalus, Tinca tinca, Pseudorasbora parva, Esox lucius, Silurus glanis, Stizostedion lucioperca, Perca fluviatilis, Lepomis gibbosus, Acipenser ruthenus. The fish came from rivers (Danube, Bega, Timis, Barzava, Nera and reservoirs (Surduc, Pischia, Sacosu Turcesc, Ghiroda,Ineu and irrigation chanell of Giroc-Chisoda. It has been performed the microscopical examination of gills and skin, as well as the macroscopical and stereomicroscopical examination of organs and muscles, being identified 45 species of parasites as follows:•Protozoa: 8 species (4 species of Myxozoa and 4 species of Ciliata. •Monogena: 5 species•Trematoda: 11 species•Cestoda: 8 species•Nematoda: 7 species•Acanthocephala: 4species•Anellida (Hirudina: 2 species•Crustacea: 5 species (Copepoda: 4 species, Branchiura:1 specia.The variety of parasites from the Banat fishes it is related with the diversity of the regional water conditions.

  8. 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). PMID:26687501

  9. Endocrine mediation of vertebrate male alternative reproductive tactics: the next generation of studies.

    Science.gov (United States)

    Knapp, Rosemary

    2003-11-01

    In many species of animals, males may achieve reproductive success via one of several alternative reproductive tactics. Over the past decade or so, there has been a concerted effort to investigate endocrine mechanisms that underlie such discrete behavioral (and often morphological) variation. In vertebrates, the first generation of studies focused on potential organizational or activational effects of steroid hormones (Moore, 1991; Moore et al., 1998). Some of these studies have made it clear that, in addition to circulating hormone levels, one must also consider other aspects of the endocrine system, including hormone receptors, binding globulins and potential interactions among endocrine axes. In this paper, I review recent work on endocrine mechanisms and suggest possibilities for future investigation. I highlight how individual variation in sensitivity to environmental conditions, particularly with respect to various stressors, may account for the existence of alternative male reproductive phenotypes. Along these lines, I briefly explain the logic behind our work with male phenotypes of longear sunfish (Lepomis megalotis) that is aimed at determining the tissue-specific distribution and activity of two enzymes that are common to androgen and glucocorticoid metabolism. A major goal of our work is to examine the potential role of steroidogenic enzymes in the transduction of environmental information to influence the expression of alternative male reproductive phenotypes. PMID:21680474

  10. 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.

  11. 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).

  12. Enantioselective analysis of non-steroidal anti-inflammatory drugs in freshwater fish based on microextraction with a supramolecular liquid and chiral liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Caballo, Carmen; Sicilia, Maria Dolores; Rubio, Soledad

    2015-06-01

    Toxicity of pharmaceuticals to aquatic biota is still largely unknown, and no research on the stereoselective toxicity of chiral drugs to these organisms has been undertaken to date. Because of the lack of analytical methods available for this purpose, this manuscript deals, for the first time, with the enantioselective analysis of the non-steroidal anti-inflammatory drugs (NSAIDs) ibuprofen, naproxen and ketoprofen in freshwater fish. The method was based on the microextraction of NSAIDs from fish muscle with a supramolecular liquid made up of inverted hexagonal aggregates of decanoic acid, their enantiomeric separation by liquid chromatography onto a (R)-1-naphthylglycine and 3,5-dinitrobenzoic acid stationary phase and quantification by tandem mass spectrometry. Limits of quantitation (LOQs) for NSAID enantiomers were in the range 1.7-3.3 ng g(-1). Absolute recoveries were from 97 to 104 %, which indicated the high extraction efficiency of the supramolecular solvent. Extraction equilibrium conditions were reached after 10 min which permitted fast sample treatment. Relative standard deviations for enantiomers in fish muscle were always below 6 %. Isotopically labelled internal standards were used to compensate for matrix interferences. The method in-house validation was carried out with the Oncorhynchus mykiss species, and it was applied to the determination of NSAID enantiomers in different fortified freshwater fish species (Alburnus alburnus, Lepomis gibbosus, Micropterus salmoides, O. mykiss and Cyprinus carpio). PMID:25869485

  13. Concentration trends for lead and calcium-normalized lead in fish fillets from the Big River, a mining-contaminated stream in southeastern Missouri USA

    Science.gov (United States)

    Schmitt, Christopher J.; McKee, Michael J.

    2016-01-01

    Lead (Pb) and calcium (Ca) concentrations were measured in fillet samples of longear sunfish (Lepomis megalotis) and redhorse suckers (Moxostoma spp.) collected in 2005–2012 from the Big River, which drains a historical mining area in southeastern Missouri and where a consumption advisory is in effect due to elevated Pb concentrations in fish. Lead tends to accumulated in Ca-rich tissues such as bone and scale. Concentrations of Pb in fish muscle are typically low, but can become elevated in fillets from Pb-contaminated sites depending in part on how much bone, scale, and skin is included in the sample. We used analysis-of-covariance to normalize Pb concentration to the geometric mean Ca concentration (415 ug/g wet weight, ww), which reduced variation between taxa, sites, and years, as was the number of samples that exceeded Missouri consumption advisory threshold (300 ng/g ww). Concentrations of Pb in 2005–2012 were lower than in the past, especially after Ca-normalization, but the consumption advisory is still warranted because concentrations were >300 ng/g ww in samples of both taxa from contaminated sites. For monitoring purposes, a simple linear regression model is proposed for estimating Ca-normalized Pb concentrations in fillets from Pb:Ca molar ratios as a way of reducing the effects of differing preparation methods on fillet Pb variation.

  14. New species of Proterometra (Digenea: Azygiidae) and its life cycle in the Chickasawhay River, Mississippi, USA, with supplemental observations of Proterometra autraini.

    Science.gov (United States)

    Womble, Matthew R; Orélis-Ribeiro, Raphael; Bullard, Stephen A

    2016-02-01

    We describe Proterometra ariasae n. sp. based upon cercariae shed from a freshwater snail, Pleurocera sp., and adults infecting the buccal cavity of longear sunfish, Lepomis megalotis, captured from the Chickasawhay River, Mississippi, USA. We also provide supplemental observations of cercarial and adult paratypes of Proterometra autraini from the Au Train River, Michigan, USA. Sequence data for the ribosomal internal transcribed spacer 2 (ITS2) from adults and cercariae of the new species were identical. Adults of the new species differ from congeners by having (i) a markedly large body, (ii) a proportionally large oral sucker, (iii) ovoid testes, (iv) a strongly muscular and laterally expanded pars prostatica, (v) a uterus that is extensively convoluted between the ovary and ventral sucker (vi) and a vitellarium as long as the caeca and extending posteriad beyond the anterior margin of the testes. Cercariae of the new species differ from those of its congeners by having (i) a tail stem that is shorter than 10mm and that lacks a medial constriction, (ii) obcordate furcae that are wider than long, (iii) mamillae distributed throughout the anterior tail stem only, and (v) a proportionally small distome that has relatively few uterine eggs and remains withdrawn in the anterior tail stem region in actively swimming cercariae. This is the first report of Proterometra from Mississippi, the second description to employ morphology and sequence data to elucidate a life cycle for Proterometra, and the third species of Proterometra from an intermediate host not assigned to Elimia. PMID:26384966

  15. The representation of conspecific sounds in the auditory brainstem of teleost fishes.

    Science.gov (United States)

    Wysocki, Lidia Eva; Ladich, Friedrich

    2003-07-01

    Temporal patterns of sounds are thought to be the most important carriers of acoustic information in teleost fishes. In order to investigate how conspecific sounds are processed by the auditory system, auditory brainstem responses (ABRs) elicited by conspecific sounds were recorded in five species of teleosts. In the catfishes Platydoras costatus and Pimelodus pictus, the loach Botia modesta and the labyrinth fish Trichopsis vittata, all of which are hearing specialists, each pulse within the sounds elicited a separate brainwave that closely followed the temporal structure. The ABRs of P. costatus and B. modesta also represent amplitude patterns of conspecific sounds. By contrast, ABRs of the sunfish Lepomis gibbosus, a hearing non-specialist, consisted of long series of waves that could not be attributed to specific sound pulses. A more detailed analysis, however, indicated that each stimulus pulse contributed to the compound ABR waveform. Spectral analysis of low-pitched drumming sounds of P. pictus and corresponding ABRs showed peaks in the ABR spectra at the harmonics of the sound. Our results indicate that, besides temporal patterns, amplitude fluctuations and the frequency content of sounds can be represented in the auditory system and help the fish to extract important information for acoustic communication. PMID:12771172

  16. A minimally invasive method of piscine tissue collection and an analysis of long-term field-storage conditions for samples

    Directory of Open Access Journals (Sweden)

    Smalley John V

    2006-05-01

    Full Text Available Abstract Background The acquisition of high-quality DNA for use in phylogenetic and molecular population genetic studies is a primary concern for evolutionary and genetic researchers. Many non-destructive DNA sampling methods have been developed and are used with a variety of taxa in applications ranging from genetic stock assessment to molecular forensics. Results The authors have developed a field sampling method for obtaining high-quality DNA from sunfish (Lepomis and other freshwater fish that employs a variation on the buccal swab method and results in the collection of DNA suitable for PCR amplification and polymorphism analysis. Additionally, since the circumstances of storage are always a concern for field biologists, the authors have tested the potential storage conditions of swabbed samples and whether those conditions affect DNA extraction and PCR amplification. It was found that samples stored at room temperature in the dark for over 200 days could still yield DNA suitable for PCR amplification and polymorphism detection. Conclusion These findings suggest that valuable molecular genetic data may be obtained from tissues that have not been treated or stored under optimal field conditions. Furthermore, it is clear that the lack of adequately low temperatures during transport and long term storage should not be a barrier to anyone wishing to engage in field-based molecular genetic research.

  17. 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

  18. Competitive interactions between invasive Nile tilapia and native fish: the potential for altered trophic exchange and modification of food webs.

    Directory of Open Access Journals (Sweden)

    Charles W Martin

    Full Text Available 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.

  19. A comparison of mercury burdens between St. Marks National Wildlife Refuge and St. Andrew Bay, Florida: Evaluation of fish body burdens and physiological responses in largemouth bass, spotted seatrout, striped mullet, and sunfish

    Science.gov (United States)

    Huge, D.H.; Rauschenberger, R.H.; Wieser, F.M.; Hemming, J.M.

    2011-01-01

    Musculature from the dorsal region of 130 largemouth bass (Micropterus salmoides), 140 sunfish (Lepomis sp.), 41 spotted seatrout (Cynoscion nebulosus) and 67 striped mullet (Mugil cephalus) were collected from five estuarine and five freshwater sites within the St. Marks National Wildlife Refuge and two estuarine and two freshwater sites from St. Andrew Bay, Florida, United States of America. Musculature was analyzed for total mercury content, sagittal otoliths were removed for age determination and physiological responses were measured. Largemouth bass and sunfish from the refuge had higher mercury concentrations in musculature than those from the bay. Male spotted seatrout, male striped mullet, male and female sunfish and female largemouth bass had mercury burdens positively correlated with length. The majority of all four species of fish from both study areas contained mercury levels below 1.5 part per million, the limit for safe consumption recommended the Florida Department of Health. In comparison, a significant percentage of largemouth bass and sunfish from several sampled sites, most notably Otter Lake and Lake Renfroe within St. Marks National Wildlife Refuge, had mercury levels consistent with the health department's guidelines of 'limited consumption' or 'no consumption guidelines.'

  20. Accumulation of metals in fish from lead-zinc mining areas of southeastern Missouri, USA

    Science.gov (United States)

    Schmitt, C.J.; Brumbaugh, W.G.; May, T.W.

    2007-01-01

    The potential effects of proposed lead-zinc mining in an ecologically sensitive area were assessed by studying a nearby mining district that has been exploited for about 30 yr under contemporary environmental regulations and with modern technology. Blood and liver samples representing fish of three species (largescale stoneroller, Campostoma oligolepis, n=91; longear sunfish, Lepomis megalotis, n=105; and northern hog sucker, Hypentelium nigricans, n=20) were collected from 16 sites representing a range of conditions relative to lead-zinc mining and ore beneficiation in southeastern Missouri. Samples were analyzed for lead, zinc, and cadmium, and for a suite of biomarkers (reported in a companion paper). A subset of the hog sucker (n=9) representing three sites were also analyzed for nickel and cobalt. Blood and liver lead concentrations were highly correlated (r=0.84-0.85, Pmetals are released to streams from active lead-zinc mines and are available for uptake by aquatic organisms. ?? 2006 Elsevier Inc. All rights reserved.

  1. Use of fish-otolith-length regressions to infer size of double-crested cormorant prey fish from recovered otoliths in Lake Ontario

    Science.gov (United States)

    Ross, Robert M.; Johnson, James H.; Adams, Connie M.

    2005-01-01

    To provide a method for estimating fish size from fish otoliths for forensic applications or other predictive uses, morphometric measurements were obtained from three centrarchid fishes (pumpkinseed [Lepomis gibbosus], rock bass [Ambloplites rupestris], and smallmouth bass [Micropterus dolomieu]), two percids (yellow perch [Perca flavescens] and walleye [Stizostedion vitreum]), and one clupeid (alewife [Alosa pseudoharengus]) from the eastern basin of Lake Ontario. These species are the principal or economically important prey of Double-crested Cormorants (Phalacrocorax auritus), whose diet can be determined from regurgitated digestive pellets containing fish otoliths. A fuller understanding of the ecosystem roles of cormorants requires estimation of prey-fish size, obtainable from regressions of otolith length on fish length. Up to 100 fish of each species were collected from eastern Lake Ontario and measured for total length and otolith length. Least-squares regressions of otolith length on fish length were calculated for all species, covering life-stage ranges of immature fish to large adults near maximum known size. The regressions with 95% confidence intervals may be applicable outside the Lake Ontario ecosystem if used with caution.

  2. 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.

  3. Biomarker responses in sunfish species and largemouth bass from the Saluda River, South Carolina.

    Science.gov (United States)

    Mierzejewski, Jessica; Haney, Dennis C; van den Hurk, Peter

    2014-12-01

    The upstate and Piedmont region of South Carolina is a rapidly urbanizing area as a result of a steadily growing population. This increase in population and development has the potential to negatively impact local aquatic systems like the Saluda River due to increased pollution from runoff, and effluents from industrial and wastewater treatment facilities. During the summer months of 2010, 159 fish from the Centrarchidae family (sunfish species (Lepomis) and largemouth bass - Micropterus salmoides) were collected from 13 sites along the Saluda River. A suite of biomarker assays, including ethoxyresosufin-O-deethylase, bile fluorescence, glutathione S-transferase, thiobarbituric acid reactive substances, bile estrogens, acetylcholinesterase inhibition, metallothionein and tissue metal levels were applied to investigate the impacts of diminished water quality on fish health. Results indicate that fish from the Saluda River are responding to contamination in a site specific manner, with up to four significant biomarker responses in the most impacted sites. Sampling sites in the lower portion of the Saluda watershed are less impacted by pollution than the upper and central sections. The observed biomarker responses can be explained by the proximity of urban areas, point sources and general land use, and demonstrate the applicability of biomarkers in environmental biomonitoring programs. PMID:25173848

  4. 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.

  5. Environmental surveillance data report for the third quarter of 1987

    Energy Technology Data Exchange (ETDEWEB)

    Daniels, K.L.; Goldberg, P.Y.; Horwedel, B.M.; McCollough, I.L.; Osborne-Lee, A.E.; Owenby, R.K.; Watson, J.B.; Wilson, M.M.

    1987-12-01

    During the third quarter of 1987, over 1600 samples which represent more than 5000 analyses and measurements were collected by the Environmental Monitoring and Compliance (EMC) Department. Uranium concentrations measured on air filters near the Y-12 plant were higher than normal due to a release from that facility in May. More than 60% of the noncompliances with the NPDES permit for the third quarter occurred in July. These were primarily in total suspended solids at the Sewage Treatment Plant. The cause of these high concentrations has been explored with the plant operating staff but is currently unresolved. Because of past noncompliances in fecal coliform and chlorine concentrations at the Sewage Treatment Plant, an engineering review has been initiated to examine the present chlorination system. This review is intended to provide a permanent solution to these types of problems. Maximum concentrations of total radioactive strontium (/sup 89/Sr + /sup 90/Sr) in bluegill were lower than those measured during the second quarter. There were not significant differences in the total radioactive strontium in blue gill at any of the Clinch River locations. 17 figs., 45 tabs.

  6. Mercury concentrations in fish from a Sierra Nevada foothill reservoir located downstream from historic gold-mining operations.

    Science.gov (United States)

    Saiki, Michael K; Martin, Barbara A; May, Thomas W; Alpers, Charles N

    2010-04-01

    This study examined mercury concentrations in whole fish from Camp Far West Reservoir, an 830-ha reservoir in northern California, USA, located downstream from lands mined for gold during and following the Gold Rush of 1848-1864. Total mercury (reported as dry weight concentrations) was highest in spotted bass (mean, 0.93 microg/g; range, 0.16-4.41 microg/g) and lower in bluegill (mean, 0.45 microg/g; range, 0.22-1.96 microg/g) and threadfin shad (0.44 microg/g; range, 0.21-1.34 microg/g). Spatial patterns for mercury in fish indicated high concentrations upstream in the Bear River arm and generally lower concentrations elsewhere, including downstream near the dam. These findings coincided with patterns exhibited by methylmercury in water and sediment, and suggested that mercury-laden inflows from the Bear River were largely responsible for contaminating the reservoir ecosystem. Maximum concentrations of mercury in all three fish species, but especially bass, were high enough to warrant concern about toxic effects in fish and consumers of fish. PMID:19283498

  7. Mercury concentrations in fish from a Sierra Nevada foothill reservoir located downstream from historic gold-mining operations

    Science.gov (United States)

    Saiki, Michael K.; Martin, Barbara A.; May, Thomas W.; Alpers, Charles N.

    2010-01-01

    This study examined mercury concentrations in whole fish from Camp Far West Reservoir, an 830-ha reservoir in northern California, USA, located downstream from lands mined for gold during and following the Gold Rush of 1848–1864. Total mercury (reported as dry weight concentrations) was highest in spotted bass (mean, 0.93 μg/g; range, 0.16–4.41 μg/g) and lower in bluegill (mean, 0.45 μg/g; range, 0.22–1.96 μg/g) and threadfin shad (0.44 μg/g; range, 0.21–1.34 μg/g). Spatial patterns for mercury in fish indicated high concentrations upstream in the Bear River arm and generally lower concentrations elsewhere, including downstream near the dam. These findings coincided with patterns exhibited by methylmercury in water and sediment, and suggested that mercury-laden inflows from the Bear River were largely responsible for contaminating the reservoir ecosystem. Maximum concentrations of mercury in all three fish species, but especially bass, were high enough to warrant concern about toxic effects in fish and consumers of fish.

  8. Potential toxicity of pesticides measured in midwestern streams to aquatic organisms

    Science.gov (United States)

    Battaglin, W.; Fairchild, J.

    2002-01-01

    Society is becoming increasingly aware of the value of healthy aquatic ecosystems as well as the effects that man's activities have on those ecosystems. In recent years, many urban and industrial sources of contamination have been reduced or eliminated. The agricultural community also has worked towards reducing off-site movement of agricultural chemicals, but their use in farming is still growing. A small fraction, estimated at pesticides applied to crops are lost from fields and enter nearby streams during rainfall events. In many cases aquatic organisms are exposed to mixtures of chemicals, which may lead to greater non-target risk than that predicted based on traditional risk assessments for single chemicals. We evaluated the potential toxicity of environmental mixtures of 5 classes of pesticides using concentrations from water samples collected from ???50 sites on midwestern streams during late spring or early summer runoff events in 1989 and 1998. Toxicity index values are calculated as the concentration of the compound in the sample divided by the EC50 or LC50 of an aquatic organism. These index values are summed within a pesticide class and for all classes to determine additive pesticide class and total pesticide toxicity indices. Toxicity index values greater than 1.0 indicate probable toxicity of a class of pesticides measured in a water sample to aquatic organisms. Results indicate that some samples had probable toxicity to duckweed and green algae, but few are suspected of having significant toxicity to bluegill sunfish or chorus frogs.

  9. Use of fish embryo toxicity tests for the prediction of acute fish toxicity to chemicals.

    Science.gov (United States)

    Belanger, Scott E; Rawlings, Jane M; Carr, Gregory J

    2013-08-01

    The fish embryo test (FET) is a potential animal alternative for the acute fish toxicity (AFT) test. A comprehensive validation program assessed 20 different chemicals to understand intra- and interlaboratory variability for the FET. The FET had sufficient reproducibility across a range of potencies and modes of action. In the present study, the suitability of the FET as an alternative model is reviewed by relating FET and AFT. In total, 985 FET studies and 1531 AFT studies were summarized. The authors performed FET-AFT regressions to understand potential relationships based on physical-chemical properties, species choices, duration of exposure, chemical classes, chemical functional uses, and modes of action. The FET-AFT relationships are very robust (slopes near 1.0, intercepts near 0) across 9 orders of magnitude in potency. A recommendation for the predictive regression relationship is based on 96-h FET and AFT data: log FET median lethal concentration (LC50) = (0.989 × log fish LC50) - 0.195; n = 72 chemicals, r = 0.95, p acute fish-acute fish toxicity relationships with the following species: fathead minnow, rainbow trout, bluegill sunfish, Japanese medaka, and zebrafish. The FET is scientifically supportable as a rational animal alternative model for ecotoxicological testing of acute toxicity of chemicals to fish. PMID:23606235

  10. Potential radiation dose from eating fish exposed to actinide contamination

    International Nuclear Information System (INIS)

    The purpose of this work is to establish a maximum potential for transporting actinides to man via fish consumption. The study took place in U-pond, a nuclear waste pond on the Hanford Site. It has concentrations of 238U, 238Pu, sup(239,240)Pu and 241Am that are approx. 3 orders of magnitude greater than background levels. Fish living in the pond contain higher actinide concentrations than those observed in fish from any other location. Experiments were performed in U-Pond to determine maximum quantities of actinides that could accumulate in fillets and whole bodies of two centrarchid fish species. Doses to hypothetical consumers were then estimated. Results indicate that highest concentrations occurring in bluegill or bass muscle after more than a year's exposure to the pond would not be sufficient to produce a significant radiation dose to a human consumer, even if he ate 0.5 kg (of the order of 1 lb) of these fillets every day for 70 yr. Natural predators (heron or coyote), having lifetime diets of whole fish from U-Pond, would receive less radiation dose from the ingested actinides than from natural background sources. (author)

  11. Evaluation of management options for disposal of salt and trace element laden agricultural drainage water from the Fallon Indian Reservation, Fallon, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Tokunaga, Tetsu; Benson, S.

    1991-03-01

    This is the final report describing work performed on the Fallon Indian Reservation by the Earth Sciences Division at Lawrence Berkeley Laboratory during FY90. These investigations were initiated at the request of the United States Bureau of Reclamation in response to recent concerns regarding disposal of agriculture drainage water from the Reservation. The Reservation is transected by numerous irrigation and drainage canals, including the TJ Drain. Recent investigations by the US Fish and Wildlife Service have demonstrated that water in the TJ Drain is toxic to several aquatic indicator organisms, including bluegills, fathead minnows and daphnids. This information, coupled with recent die-offs of fish and birds, has lead to concern about continued discharge of TJ Drain water into local surface waters. In late 1990, plans for closing the TJ Drain and providing for alternative drainage were initiated. We aim to provide information for assessing options fro disposal of agricultural drainage water from the Reservation. In particular, our studies focuses on irrigation and drainage of lands currently serviced by the TJ Drain. Options for continued irrigation and drainage of the Reservation fall broadly into two categories: options that provide an alternative to drain water disposal into the SWMA; and options that include continuing the current practice of drain water disposal into the SWMA. Other options include elements of both of these alternatives. Additional discussion of specific options will follow a brief summary of the technical work supporting our assessment of drainage related issues at the Reservation. 67 refs., 57 figs., 15 tabs.

  12. Moses Lake fishery restoration project : FY 1999 annual report; ANNUAL

    International Nuclear Information System (INIS)

    The Moses Lake Project consists of 3 phases. Phase 1 is the assessment of all currently available physical and biological information, the collection of baseline biological data, the formulation of testable hypotheses, and the development of a detailed study plan to test the hypotheses. Phase 2 is dedicated to the implementation of the study plan including data collection, hypotheses testing, and the formulation of a management plan. Phase 3 of the project is the implementation of the management plan, monitoring and evaluation of the implemented recommendations. The project intends to restore the failed recreational fishery for panfish species (black crappie, bluegill and yellow perch) in Moses Lake as off site mitigation for lost recreational fishing opportunities for anadromous species in the upper Columbia River. This report summarizes the results of Phase 1 investigations and presents the study plan directed at initiating Phase 2 of the project. Phase 1of the project culminates with the formulation of testable hypotheses directed at investigating possible limiting factors to the production of panfish in Moses Lake. The limiting factors to be investigated will include water quality, habitat quantity and quality, food limitations, competition, recruitment, predation, over harvest, environmental requirements, and the physical and chemical limitations of the system in relation to the fishes

  13. Replication and persistence of VHSV IVb in freshwater turtles.

    Science.gov (United States)

    Goodwin, Andrew E; Merry, Gwenn E

    2011-05-01

    With the emergence of viral hemorrhagic septicemia virus (VHSV) strain IVb in the Great Lakes of North America, hatchery managers have become concerned that this important pathogen could be transmitted by animals other than fish. Turtles are likely candidates because they are poikilotherms that feed on dead fish, but there are very few reports of rhabdovirus infections in reptiles and no reports of the fish rhabdoviruses in animals other than teleosts. We injected common snapping turtles Chelydra serpentine and red-eared sliders Trachemys scripta elegans intraperitoneally with 10(4) median tissue culture infectious dose (TCID50) of VHSV-IVb and 21 d later were able to detect the virus by quantitative real-time reverse transcriptase PCR (qrt-RTPCR) in pools of kidney, liver, and spleen. In a second experiment, snapping turtles, red-eared sliders, yellow-bellied sliders T. scripta scripta, and northern map turtles Grapetemys geographica at 14 degrees C were allowed to feed on tissues from bluegill dying of VHSV IVb disease. Turtle kidney, spleen, and brain pools were not positive by qrt-RTPCR on Day 3 post feeding, but were positive on Days 10 and 20. Map turtles on Day 20 post-feeding were positive by both qrt-RTPCR and by cell culture. Our work shows that turtles that consume infected fish are a possible vector for VHSV IVb, and that the fish rhabdoviruses may have a broader host range than previously suspected. PMID:21790064

  14. Potential radiation dose from eating fish exposed to actinide contamination

    Energy Technology Data Exchange (ETDEWEB)

    Emery, R.M.; Klopfer, D.C.; Baker, D.A.; Soldat, J.K. (Battelle Pacific Northwest Labs., Richland, WA (USA))

    1981-04-01

    The purpose of this work is to establish a maximum potential for transporting actinides to man via fish consumption. The study took place in U-pond, a nuclear waste pond on the Hanford Site. It has concentrations of /sup 238/U, /sup 238/Pu, sup(239,240)Pu and /sup 241/Am that are approx. 3 orders of magnitude greater than background levels. Fish living in the pond contain higher actinide concentrations than those observed in fish from any other location. Experiments were performed in U-Pond to determine maximum quantities of actinides that could accumulate in fillets and whole bodies of two centrarchid fish species. Doses to hypothetical consumers were then estimated. Results indicate that highest concentrations occurring in bluegill or bass muscle after more than a year's exposure to the pond would not be sufficient to produce a significant radiation dose to a human consumer, even if he ate 0.5 kg (of the order of 1 lb) of these fillets every day for 70 yr. Natural predators (heron or coyote), having lifetime diets of whole fish from U-Pond, would receive less radiation dose from the ingested actinides than from natural background sources.

  15. Potential radiation dose from eating fish exposed to actinide contamination

    Energy Technology Data Exchange (ETDEWEB)

    Emery, R.M.; Klopfer, D.C.; Baker, D.A.; Soldat, J.K.

    1980-01-01

    The purpose of this work is to establish a maximum potential for transporting actinides to man via fish consumption. The study took place in U-Pond, a nuclear waste pond on the Hanford Site. It has concentrations of /sup 238/U, /sup 238/Pu, /sup 239,240/Pu and /sup 241/Am that are approximately three orders of magnitude greater than background levels. Fish living in the pond contain higher actinide concentrations than those observed in fish from any other location. Experiments were performed in U-pond to determine maximum quantities of actinides that could accumulate in fillets and whole bodies of two centrarchid fish species. Doses to hypothetical consumers were then estimated by assuming that actinide behavior in their bodies was similar to that defined for Standard Man by the International Commission on Radiological Protection. Results indicate that highest concentrations occurring in bluegill or bass muscle after more than a year's exposure to the pond would not be sufficient to produce a significant radiation dose to a human consumer, even if he ate 0.5 kg (approx.1 lb) of these fillets every day for 70 years. Natural predators (heron or coyote), having lifetime diets of whole fish from U-Pond, would receive less radiation dose from the ingested actinides than from natural background sources. 34 refs., 5 figs., 4 tabs.

  16. Replication of Infectious Pancreatic Necrosis Virus in Different Cell Lines and in Rainbow Trout (Oncorhynchus Mykiss Fingerlings

    Directory of Open Access Journals (Sweden)

    Matvienko Natalija

    2014-07-01

    Full Text Available The results of a study of Infectious Pancreatic Necrosis Virus (IPNV isolated in natural reservoirs in Ukraine are presented. The pathogenicity of isolates was investigated in vitro on cell cultures and in vivo on rainbow trout, Oncorhynchus mykiss (Walbaum, fingerlings. Experimental indications were that the Ukrainian IPNV isolates have affinity with reference European strains. During the reproduction of these isolates in cell cultures of FHM (fat head minnow, RTG-2 (rainbow trout gonads, and BF-2 (bluegill caudal peduncle, complicated degenerative changes were visible that finally led to the full destruction of cell monolayers. The experimental infection of rainbow trout fingerlings resulted in typical disease symptoms that were systemic. However, obvious evidence of viral infection was noted in single individuals only, and the majority of experimental fish died without visible disease symptoms. During the study of physicochemical properties, it was noted that Ukrainian isolates completely lost their infectivity with chloroform treatment and heating to 60°C. This proved that IPNV isolates are resistant to Ion concentrations in the range of pH 3.0 to 12.0.

  17. In vivo and in vitro phenotypic differences between Great Lakes VHSV genotype IVb isolates with sequence types vcG001 and vcG002

    Science.gov (United States)

    Imanse, Sierra M.; Cornwell, Emily R.; Getchell, Rodman G.; Kurath, Gael; Bowser, Paul R.

    2014-01-01

    Viral hemorrhagic septicemia virus (VHSV) is an aquatic rhabdovirus first recognized in farmed rainbow trout in Denmark. In the past decade, a new genotype of this virus, IVb was discovered in the Laurentian Great Lakes basin and has caused several massive die-offs in some of the 28 species of susceptible North American freshwater fishes. Since its colonization of the Great Lakes, several closely related sequence types within genotype IVb have been reported, the two most common of which are vcG001 and vcG002. These sequence types have different spatial distributions in the Great Lakes. The aim of this study was to determine whether the genotypic differences between representative vcG001 (isolate MI03) and vcG002 (isolate 2010-030 #91) isolates correspond to phenotypic differences in terms of virulence using both in vitro and in vivo approaches. In vitro infection of epithelioma papulosum cyprini (EPC), bluegill fry (BF-2), and Chinook salmon embryo (CHSE) cells demonstrated some differences in onset and rate of growth in EPC and BF-2 cells, without any difference in the quantity of RNA produced. In vivo infection of round gobies (Neogobius melanostomus) via immersion exposure to different concentrations of vcG001 or vcG002 caused a significantly greater mortality in round gobies exposed to 102 plaque forming units ml− 1 of vcG001. These experiments suggest that there are phenotypic differences between Great Lakes isolates of VHSV genotype IVb.

  18. Cryptosporidium parvum is not transmissible to fish, amphibians, or reptiles.

    Science.gov (United States)

    Graczyk, T K; Fayer, R; Cranfield, M R

    1996-10-01

    A recent report suggested that an isolate of Cryptosporidium parvum had established infections in fish, amphibians, and reptiles and raises concern that animals other than mammals might be a potential source of waterborne Cryptosporidium oocysts. To test this possibility, viable C. parvum oocysts, infectious for neonatal BALB/c mice, were delivered by gastric intubation to bluegill sunfish, poison-dart frogs, African clawed frogs, bearded dragon lizards, and corn snakes. Histological sections of the stomach, jejunum, ileum, and cloaca prepared from tissues collected on days 7 and 14 postinoculation (PI) were negative for Cryptosporidium developmental stages. However, inoculum-derived oocysts were detectable by fluorescein-labeled monoclonal antibody in feces of inoculated animals from day 1 to day 12 PI in fish and frogs, and up to day 14 PI in lizards. Snakes did not defecate for 14 days PI. Impression smears taken at necropsy on days 7 and 14 PI revealed C. parvum oocysts in the lumen of the cloaca of 2 fish and 1 lizard on day 7 PI only. Because tissue stages of the pathogen were not found, it appears that C. parvum was not heterologously transmitted to lower vertebrates. Under certain circumstances, however, such as after the ingestion of C. parvum-infected prey, lower vertebrates may disseminate C. parvum oocysts in the environment. PMID:8885883

  19. Potential radiation dose from eating fish exposed to actinide contamination

    International Nuclear Information System (INIS)

    The purpose of this work is to establish a maximum potential for transporting actinides to man via fish consumption. The study took place in U-Pond, a nuclear waste pond on the Hanford Site. It has concentrations of 238U, 238Pu, /sup 239,240/Pu and 241Am that are approximately three orders of magnitude greater than background levels. Fish living in the pond contain higher actinide concentrations than those observed in fish from any other location. Experiments were performed in U-pond to determine maximum quantities of actinides that could accumulate in fillets and whole bodies of two centrarchid fish species. Doses to hypothetical consumers were then estimated by assuming that actinide behavior in their bodies was similar to that defined for Standard Man by the International Commission on Radiological Protection. Results indicate that highest concentrations occurring in bluegill or bass muscle after more than a year's exposure to the pond would not be sufficient to produce a significant radiation dose to a human consumer, even if he ate 0.5 kg (∼1 lb) of these fillets every day for 70 years. Natural predators (heron or coyote), having lifetime diets of whole fish from U-Pond, would receive less radiation dose from the ingested actinides than from natural background sources. 34 refs., 5 figs., 4 tabs

  20. Steel Creek fish: L-Lake/Steel Creek Biological Monitoring Program, January 1986--December 1987

    Energy Technology Data Exchange (ETDEWEB)

    Paller, M.H.; Heuer, J.H.; Kissick, L.A.

    1988-03-01

    Fish samples were collected from Steel Creek during 1986 and 1987 following the impoundment of the headwaters of the stream to form L-Lake, a cooling reservoir for L-Reactor which began operating late in 1985. Electrofishing and ichthyoplankton sample stations were located throughout the creek. Fykenetting sample stations were located in the creek mouth and just above the Steel Creek swamp. Larval fish and fish eggs were collected with 0.5 m plankton nets. Multivariate analysis of the electrofishing data suggested that the fish assemblages in Steel Creek exhibited structural differences associated with proximity to L-Lake, and habitat gradients of current velocity, depth, and canopy cover. The Steel Creek corridor, a lotic reach beginning at the base of the L-Lake embankment was dominated by stream species and bluegill. The delta/swamp, formed where Steel Creek enters the Savannah River floodplain, was dominated by fishes characteristic of slow flowing waters and heavily vegetated habitats. The large channel draining the swamp supported many of the species found in the swamp plus riverine and anadromous forms.

  1. Mercury concentrations in pond fish in relation to a coal-fired power plant

    International Nuclear Information System (INIS)

    Although many studies have reported that atmospheric mercury is the primary cause for bioaccumulation in fish from remote lakes, few data are available on the effects of possible near-field deposition on fish from nearby waters. The authors surveyed mercury concentrations in fish from 23 ponds in the vicinity of the coal-burning Dickerson Power Plant (Dickerson, MD). A stratified random sampling design was used to select ponds within zones delineated by concentric rings mapped at 3, 7, 10, and 15 km from the plant. For each pond, mercury concentrations were measured by cold vapor atomic absorption spectrometry in sunfish (bluegill, pumpkin seed, or green sunfish), and largemouth bass, which were present in 14 of the ponds. Mean concentrations in the ponds ranged from 0.03 to 0.38 ppm for sunfish and from 0.04 to 0.43 ppm for bass. Alkalinity, pH, conductivity, hardness, and fish length were measured. Stepwise multiple regression identified variables related to tissue concentrations. Differences between strata were tested with ANCOVA. The pattern of concentrations was compared to the pattern of wet deposition predicted by a model. The predicted pattern of local wet deposition did not match the observed pattern of mercury bioaccumulation. This research was sponsored by the Maryland Department of Natural Resources, Power Plant Research Program

  2. Moses Lake Fishery Restoration Project : FY 1999 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    None given

    2000-12-01

    The Moses Lake Project consists of 3 phases. Phase 1 is the assessment of all currently available physical and biological information, the collection of baseline biological data, the formulation of testable hypotheses, and the development of a detailed study plan to test the hypotheses. Phase 2 is dedicated to the implementation of the study plan including data collection, hypotheses testing, and the formulation of a management plan. Phase 3 of the project is the implementation of the management plan, monitoring and evaluation of the implemented recommendations. The project intends to restore the failed recreational fishery for panfish species (black crappie, bluegill and yellow perch) in Moses Lake as off site mitigation for lost recreational fishing opportunities for anadromous species in the upper Columbia River. This report summarizes the results of Phase 1 investigations and presents the study plan directed at initiating Phase 2 of the project. Phase 1of the project culminates with the formulation of testable hypotheses directed at investigating possible limiting factors to the production of panfish in Moses Lake. The limiting factors to be investigated will include water quality, habitat quantity and quality, food limitations, competition, recruitment, predation, over harvest, environmental requirements, and the physical and chemical limitations of the system in relation to the fishes.

  3. Toxicology of 2,3,7,8 - tetrachlorodibenzo - P - dioxin (TCDD) in aquatic and mammalian species. Part 1. TCDD toxicity, bioaccumulation and biotransformation in fish. Part 2. Effects of TCDD on testicular steroid secretion by the rat

    International Nuclear Information System (INIS)

    Experiments were conducted to augment the limited information available on TCDD toxicity, disposition and metabolism in fish. Toxicity was assessed following administration of graded concentrations of TCDD to juvenile rainbow trout, yellow perch, carp, bluegill, large-mouth bass, and bullhead. TCDD-induced mortality was delayed at least one week post-treatment and LD50 values ranged from 3-16 μg/kg. TCDD-induced morphologic lesions and decreases in body weight were observed and these effects were both species- and dose-dependent. Accumulation, tissue distribution, and depuration of TCDD-derived 3H were examined in juvenile rainbow trout and yellow perch fed a diet containing 3H-TCDD. Non-edible fatty tissues were the major depots for TCDD-derived 3H in both species while skeletal muscle was a minor site of TCDD accumulation. Species differences in TCDD distribution were evident. TCDD produces a dose-related androgenic deficiency in male rats without affecting a change in plasma LH. Decapsulated and isolated perfused testes were used to determine if this androgenic deficiency is due to TCDD-mediated decreases in testicular steroidogenic responsiveness. hCG-Stimulated testosterone secretion and post-perfusion intratesticular testosterone were decreased in TCDD-treated rats indicating a defect in testosterone synthesis

  4. How well can fishes prey on zebra mussels in eastern North America?

    Science.gov (United States)

    French, John R. P., III

    1993-01-01

    Literature on mollusk-eating fishes was reviewed to determine the potential for different species of fish to control zebra mussels in eastern North America. At least six species are potential predators of zebra mussels because they possess (1) both upper and lower pharyngeal teeth or (2) lower pharyngeal teeth and chewing pads located on the dorsal roof for crushing mollusk shells. Freshwater drum (Aplodinotus grunniens) and two centrarchids, redear sunfish (Lepomis microlophus) and pumpkinseed (L. gibbosus), possess both upper and lower pharyngeal teeth and are likely to consume more zebra mussels than fishes with only lower pharyngeal teeth. Only two catostomid species, copper and river redhorses (Moxostoma hubbsi and M. carinatum), have chewing pads that enable them to crush mollusks. The exotic omnivorous common carp (Cyprinus carpio), possessing lower teeth and a chewing pad, may prey on zebra mussels when aquatic insect larvae, its preferred food, become rare. Managing populations of drum, sunfishes and redhorses to reduce exploitation of large individuals and improve their habitats are suggested as means to intensify biological control of zebra mussels in eastern North America. Other Eurasian molluscivores, the roach (Rutilus rutilus) and the black carp (Mylopharyngodon piceus) should not be introduced into North America because research has shown repeatedly that an introduced biological controller usually does not forage for unwanted pests or reside only in preferred habitats of pests. Drum, sunfishes and redhorses should be preferred over these exotics as biological controllers of zebra mussels in North America because these native fishes will likely occupy newly established habitats of zebra mussels.

  5. 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

  6. Early life history and spatiotemporal changes in distribution of the rediscovered Suwannee moccasinshell Medionidus walkeri (Bivalvia: Unionidae)

    Science.gov (United States)

    Johnson, Nathan A.; Mcleod, John; Holcomb, Jordan; Rowe, Matthew T.; Williams, James D.

    2016-01-01

    Accurate distribution data are critical to the development of conservation and management strategies for imperiled species, particularly for narrow endemics with life history traits that make them vulnerable to extinction. Medionidus walkeri is a rare freshwater mussel endemic to the Suwannee River Basin in southeastern North America. This species was rediscovered in 2012 after a 16-year hiatus between collections and is currently proposed for listing under the Endangered Species Act. Our study fills knowledge gaps regarding changes in distribution and early life history requirements of M. walkeri. Spatiotemporal changes in M. walkeri distribution were displayed using a conservation status assessment map incorporating metadata from 98 historical (1916–1999) and 401 recent (2000–2015) site surveys from museums and field notes representing records for 312 specimens. Recent surveys detected M. walkeri only in the middle Suwannee subbasin (n = 86, 22 locations) and lower Santa Fe subbasin (n = 2, 2 locations), and it appears the species may be extirpated from 67% of historically occupied 10-digit HUCs. In our laboratory experiments, M. walkeri successfully metamorphosed onPercina nigrofasciata (56.2% ± 8.9) and Etheostoma edwini (16.1% ± 7.9) but not on Trinectes maculatus, Lepomis marginatus, Notropis texanus, Noturus leptacanthus, Etheostoma fusiforme, orGambusia holbrooki. We characterize M. walkeri as a lure-displaying host fish specialist and a long-term brooder (bradytictic), gravid from fall to early summer of the following year. The early life history and distribution data presented here provide the baseline framework for listing decisions and future efforts to conserve and recover the species.

  7. 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.

  8. Frequency and Severity of Trauma in Fishes Subjected to Multiple-pass Depletion Electrofishing

    Science.gov (United States)

    Panek, Frank; Densmore, Christine L.

    2013-01-01

    The incidence and severity of trauma associated with multiple-pass electrofishing and the effects on short-term (30-d) survival and growth of Rainbow Trout Oncorhynchus mykiss, Brook Trout Salvelinus fontinalis, and five representative co-inhabiting nontarget or bycatch species were examined. Fish were held in four rectangular fiberglass tanks (190 × 66 cm) equipped with electrodes, a gravel–cobble stream substrate, and continuous water flow. Fish were exposed to one, two, or three electroshocks (100-V, 60-Hz pulsed DC) spaced 1 h apart or were held as a control. The heterogeneous field produced a mean (±SD) voltage gradient of 0.23 ± 0.024 V/cm (range = 0.20–0.30 V/cm) with a duty cycle of 30% and a 5-s exposure. Radiographs of 355 fish were examined for evidence of spinal injuries, and necropsies were performed on 303 fish to assess hemorrhagic trauma in soft tissue. Using linear regression, we demonstrated significant relationships between the number of electrical shocks and the frequency and severity of hemorrhagic and spinal trauma in each of the nontarget species (Potomac Sculpin Cottus girardi, Channel Catfish Ictalurus punctatus, Fathead Minnow Pimephales promelas, Green Sunfish Lepomis cyanellus, and Largemouth Bass Micropterus salmoides). Most of the injuries in these species were either minor or moderate. Rainbow Trout and Brook Trout generally sustained the highest incidence and severity of injuries, but those injuries were generally independent of the number of treatments. The 30-d postshock survival for the trout species was greater than 94%; survival for the bycatch species ranged from 80% (Fathead Minnow) to 100% (Green Sunfish and Channel Catfish). There were no significant differences in 30-d postshock condition factors despite observations of altered feeding behavior lasting several days to 1 week posttreatment in several of the study species.

  9. Ecological half-life of 137Cs in fish from a stream contaminated by nuclear reactor effluents

    International Nuclear Information System (INIS)

    Radiocesium (137Cs) concentrations were determined during 1974, 1981 and 1998 for seven species of fish inhabiting a stream (Steel Creek) contaminated by effluents from a nuclear reactor to examine the decline of this radionuclide in a natural ecosystem. Median 137Cs concentrations were highest in Micropterus salmoides (largemouth bass) during each year of the investigation (1974=6.67 Bq g-1 dry wt. of whole body; 1981=3.72 Bq g-1; 1998=0.35 Bq g-1), but no patterns of differences were observed among Aphredoderus sayanus (pirate perch), Esox americanus (redfin pickerel), Lepomis auritus (redbreast sunfish), L. gulosus (warmouth), L. punctatus (spotted sunfish), and Notropis cummingsae (dusky shiner). Results demonstrated a rapid decline in 137Cs within fish from Steel Creek during the 24-year period. For example, 137Cs concentrations in all fish species declined significantly among years, even after accounting for radioactive decay. The observed percent declines in 137Cs concentrations of individual species were 3-4 times greater between 1974 and 1981 compared to that expected by physical decay alone, and 2-3 times greater during 1981-1998. Ecological half-lives (EHLs) of 137Cs in fish ranged from 4.43 years in A. sayanus to 6.53 years in L. gulosus. The EHL for 137Cs in all fish species combined was 5.54 years. Current levels of 137Cs in fish from Steel Creek (1.16 Bq g-1 dry wt. of whole body to below detection limits) indicate that the consumption of fish from this ecosystem poses little risk to humans and sensitive wildlife species. These results demonstrate the importance of incorporating the concept of ecological half-life into determinations concerning the length and severity of potential risks associated with radiocontaminants

  10. Stress in the neighborhood: Tissue glucocorticoids relative to stream quality for five species of fish.

    Science.gov (United States)

    King, Gregory D; Chapman, Jacqueline M; Cooke, Steven J; Suski, Cory D

    2016-03-15

    Anthropogenic alterations to terrestrial habitat (e.g., urbanization, deforestation, agriculture) can have a variety of negative effects on watercourses that flow through disturbed landscapes. Currently, the relationship between stream habitat quality and fish condition remains poorly understood. The use of physiological metrics such as glucocorticoids (GCs) provides a useful tool for quantifying these effects by relating the health of resident fishes to stream quality. To date, however, most studies that measure GC levels tend to focus on a single, large-bodied species, rather than evaluating how GCs may be influenced differently between species in a community. In this study, we measured cortisol, the glucocorticoid found in fishes, from fish tissues to quantify effects of habitat degradation on the glucocorticoid function of five species of juvenile and small-bodied stream fish which differ ecologically and phylogenetically. Largemouth bass Micropterus salmoides, brown bullhead Ameiurus nebulosus, white sucker Catostomus commersonii, pumpkinseed Lepomis gibbosus, and logperch Percina caprodes were sampled from a reference and a degraded stream. Upon capture, fish were either euthanized immediately, to quantify baseline stress parameters, or following a standardized stressor, to quantify GC responsiveness. As a result of stream degradation largemouth bass possessed altered baseline GC concentrations and brown bullhead and logperch had altered GC responses to a stressor. White sucker and pumpkinseed did not demonstrate any alteration in baseline or post-stress GC concentrations. Together, our results show that different species residing in identical habitats can demonstrate a variety of responses to environmental stress, highlighting the variation in physiological ability to cope under poor environmental conditions, as well as the difficulty of predicting GC dynamics in wild animals. Understanding the relationships between GC function, habitat quality, and

  11. An invasion record for the swimbladder nematode Anguillicoloides crassus in European eel Anguilla anguilla in a deep warm-monomictic [corrected] lake, from invasion to steady state.

    Science.gov (United States)

    Bernies, D; Brinker, A; Daugschies, A

    2011-09-01

    This study is the first account of the establishment and development of the neozoic nematode parasite Anguillicoloides crassus in its host, the European eel Anguilla anguilla, in a deep, warm-monomictic [corrected] lake. A 21 year study of A. crassus took place in Upper Lake Constance (ULC), Europe's second largest pre-alpine lake. The study included two extensive surveys, one in 1991 during the initial parasite invasion phase and the second in 2006 when the infection was well established. The subtropical swimbladder nematode A. crassus was first recorded in A. anguilla in ULC in 1989. Prevalence reached 60% in 1992 and remained at this level until 2007. In 2008, prevalence decreased to 48%. Infection intensity peaked in 1993 at a mean value of 16 adult parasites per host fish. Around 90% of all A. anguilla examined displayed swimbladder lesions, with a significant trend to increasing severity over time. Moreover, heavy swimbladder lesions were seen in c. 10% of A. anguilla ready to migrate to their spawning habitat. Both ruffe Gymnocephalus cernuus and sunfish Lepomis gibbosus serve as paratenic hosts for A. crassus in ULC. Gymnocephalus cernuus seems to be the main vector, and infection is especially frequent in spring possibly caused by reduced immune system efficacy of G. cernuus during winter. In 1991, hypochromic anaemia was prevalent in ULC A. anguilla acutely infected with A. crassus, whereas in 2006 blood values were indicative of chronic infection. The growth and survival rates of A. anguilla during their continental phase were not noticeably altered in infected fish, but damage to the swimbladder probably impairs migration potential and thus the subsequent breeding success of the oceanic phase. PMID:21884109

  12. Biomarkers of metals exposure in fish from lead-zinc mining areas of Southeastern Missouri, USA

    Science.gov (United States)

    Schmitt, C.J.; Whyte, J.J.; Roberts, A.P.; Annis, M.L.; May, T.W.; Tillitt, D.E.

    2007-01-01

    The potential effects of proposed lead-zinc mining in an ecologically sensitive area were assessed by studying a nearby mining district that has been exploited for about 30 y under contemporary environmental regulations and with modern technology. Blood and liver samples representing fish of three species (largescale stoneroller, Campostoma oligolepis, n=91; longear sunfish, Lepomis megalotis, n=105; and northern hog sucker, Hypentelium nigricans, n=20) from 16 sites representing a range of conditions relative to mining activities were collected. Samples were analyzed for metals (also reported in a companion paper) and for biomarkers of metals exposure [erythrocyte ??-aminolevulinic acid dehydratase (ALA-D) activity; concentrations of zinc protoporphyrin (ZPP), iron, and hemoglobin (Hb) in blood; and hepatic metallothionein (MT) gene expression and lipid peroxidation]. Blood lead concentrations were significantly higher and ALA-D activity significantly lower in all species at sites nearest to active lead-zinc mines and in a stream contaminated by historical mining than at reference or downstream sites. ALA-D activity was also negatively correlated with blood lead concentrations in all three species but not with other metals. Iron and Hb concentrations were positively correlated in all three species, but were not correlated with any other metals in blood or liver in any species. MT gene expression was positively correlated with liver zinc concentrations, but neither MT nor lipid peroxidase differences among fish grouped according to lead concentrations were statistically significant. ZPP was not detected by hematofluorometry in most fish, but fish with detectable ZPP were from sites affected by mining. Collectively, these results confirm that metals are released to streams from active lead-zinc mining sites and are accumulated by fish. ?? 2007 Elsevier Inc. All rights reserved.

  13. 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

  14. Prey availability and diet of the Eurasian otter (Lutra lutra) on a large reservoir and associated tributaries

    Energy Technology Data Exchange (ETDEWEB)

    Sales-Luis, T.; Pedroso, N.M.; Santos-Reis, M. [Lisbon Univ., Lisbon (Portugal). Dept. of Animal Biology

    2007-11-15

    The increase in the construction of large dams over the past 50 years has resulted in a significant change to original river systems with impacts on riparian habitats, fish populations and biological communities in rivers. This study focused on the feeding habits and decline of the Eurasian otter resulting from the construction of large dammed reservoirs. Data presented in this paper was from a research project conducted at the Aguieira reservoir in Portugal in the medium section of the Mondego River and its 6 tributaries. One of the consequences of dam construction is the change in prey communities. It was noted that the otter's foraging ability is restricted in reservoirs because of the steep margins and deep waters. In this study, prey consumption was compared with prey abundance along with diet composition in both the reservoir and associated tributaries. Eurasian otter spraints collected at the Aguieira hydroelectric dam and tributaries were analysed to assess diet compared with prey availability. Fyke and trammel nets were used to evaluate fish and crayfish abundances in the reservoir, while electrofishing was used to estimate prey availability in the tributaries. Fish (primarily Lepomis gibbosus) was the main prey in both the reservoir and its tributaries. The abundance of L. gibbosus in the reservoir and its near absence in the tributaries indicates that otters using the tributaries feed predominantly in the reservoir. Seasonal dietary variations corresponded to increased availability of nonfish prey categories. The study showed that otters do not consume L. gibbosus according to its availability. It was determined that the tributaries provide important otter shelter areas that are scarce at the edge of the reservoir. As such, care should be taken to minimize disturbance in the surrounding catchments to ensure the survival of otter populations. 71 refs., 4 tabs., 4 figs.

  15. Estimation of appropriate background concentrations for assessing mercury contamination in fish

    International Nuclear Information System (INIS)

    One goal of environmental restoration at contaminated industrial or hazardous waste sites is the prevention of any further release of contaminants. As a consequence of successful remediation, it is hoped that elevated contaminant concentrations in biota will return to levels characteristic of environments uncontaminated by point sources. To evaluate the efficacy of such an environmental cleanup, it is necessary to know what background contaminant concentrations would typify uncontaminated conditions in the systems of interest. An accurate estimate of an appropriate background mercury concentration in fish is needed to determine the extent to which industrial mercury discharges produce elevated mercury concentration in fish in receiving waters, and to determine the concentration in fish that would represent restoration to uncontaminated status. Losses of large quantities of mercury in the 1950s at the U.S. Department of Energy (DOE) facilities in Oak Ridge, Tennessee resulted in continued chronic contamination of several small streams and the downstream river/reservoir system. mercury concentrations in axial muscle of fish exceed 1 μg/g wet wt. near the source, and decline to much lower concentrations 20 km downstream in Watts Bar Reservoir. Although remedial efforts are underway, the facility remains a continuing source of mercury contamination to the downstream waters. This study measures mercury concentration in bluegill and redbreast sunfish from streams and reservoirs near Oak Ridge, TN that are presumed to be relatively unimpacted by anthropogenic point sources of mercury to determine appropriate background levels in fish to apply in evaluating local contaminated streams and reservoirs. 16 refs., 1 fig., 1 tab

  16. Fish locomotion: kinematics and hydrodynamics of flexible foil-like fins

    Science.gov (United States)

    Lauder, George V.; Madden, Peter G. A.

    2007-11-01

    The fins of fishes are remarkable propulsive devices that appear at the origin of fishes about 500 million years ago and have been a key feature of fish evolutionary diversification. Most fish species possess both median (midline) dorsal, anal, and caudal fins as well as paired pectoral and pelvic fins. Fish fins are supported by jointed skeletal elements, fin rays, that in turn support a thin collagenous membrane. Muscles at the base of the fin attach to and actuate each fin ray, and fish fins thus generate their own hydrodynamic wake during locomotion, in addition to fluid motion induced by undulation of the body. In bony fishes, the jointed fin rays can be actively deformed and the fin surface can thus actively resist hydrodynamic loading. Fish fins are highly flexible, exhibit considerable deformation during locomotion, and can interact hydrodynamically during both propulsion and maneuvering. For example, the dorsal and anal fins shed a vortex wake that greatly modifies the flow environment experienced by the tail fin. New experimental kinematic and hydrodynamic data are presented for pectoral fin function in bluegill sunfish. The highly flexible sunfish pectoral fin moves in a complex manner with two leading edges, a spanwise wave of bending, and substantial changes in area through the fin beat cycle. Data from scanning particle image velocimetry (PIV) and time-resolved stereo PIV show that the pectoral fin generates thrust throughout the fin beat cycle, and that there is no time of net drag. Continuous thrust production is due to fin flexibility which enables some part of the fin to generate thrust at all times and to smooth out oscillations that might arise at the transition from outstroke to instroke during the movement cycle. Computational fluid dynamic analyses of sunfish pectoral fin function corroborate this conclusion. Future research on fish fin function will benefit considerably from close integration with studies of robotic model fins.

  17. Environmental radiological studies conducted during 1986 in the vicinity of the Rancho Seco Nuclear Power Generating Station

    International Nuclear Information System (INIS)

    This report summarizes the information compiled in 1986 for our assessment of the environmental impact of radionuclides discharged with aqueous releases from the Rancho Seco Nuclear Power Generating Plant. In October 1984, a liquid-effluent control program was initiated that significantly reduced the quantities of radionuclides discharged with liquid waste from the plant. However, results from our sampling program in 1986 indicate that previously discharged radionuclides persist in the downstream environment and are found in many aquatic dietary components although at concentrations much lower than those measured in 1984 and 1985. The greatly reduced activities in the dietary components from the aquatic environment attest to the effectiveness of the liquid-effluent control program. Concentrations in the flesh of fish from the creeks have decreased over time and with distance from the plant outfall. The mean concentration of 137Cs in fish collected from Laguna Creek at locations more than 7.5 km from Rancho Seco is now comparable to the concentration determined in fresh-water fish randomly selected from Chicago, Illinois, markets. By August 1986, the mean concentration of 137Cs in the flesh of bluegill had fallen to 7% of the concentration measured in fish from comparable locations in 1984 and was 30% of the mean concentration measured in these fish during August 1985. Stable potassium in the water plays a major role in the accumulation of 137Cs by fish. Concentrations of 137Cs in the surface sections of creek sediments also declined between the end of 1984 and 1986 with an effective half-life of approximately 2 y. Surface soils collected around a perimeter 11 km from Rancho Seco and from ranchlands closer to the plant showed only concentrations of 137Cs originating from global fallout. Soils previously irrigated with Clay Creek water retain levels of both 134Cs and 137Cs

  18. Predicting acute aquatic toxicity of structurally diverse chemicals in fish using artificial intelligence approaches.

    Science.gov (United States)

    Singh, Kunwar P; Gupta, Shikha; Rai, Premanjali

    2013-09-01

    The research aims to develop global modeling tools capable of categorizing structurally diverse chemicals in various toxicity classes according to the EEC and European Community directives, and to predict their acute toxicity in fathead minnow using set of selected molecular descriptors. Accordingly, artificial intelligence approach based classification and regression models, such as probabilistic neural networks (PNN), generalized regression neural networks (GRNN), multilayer perceptron neural network (MLPN), radial basis function neural network (RBFN), support vector machines (SVM), gene expression programming (GEP), and decision tree (DT) were constructed using the experimental toxicity data. Diversity and non-linearity in the chemicals' data were tested using the Tanimoto similarity index and Brock-Dechert-Scheinkman statistics. Predictive and generalization abilities of various models constructed here were compared using several statistical parameters. PNN and GRNN models performed relatively better than MLPN, RBFN, SVM, GEP, and DT. Both in two and four category classifications, PNN yielded a considerably high accuracy of classification in training (95.85 percent and 90.07 percent) and validation data (91.30 percent and 86.96 percent), respectively. GRNN rendered a high correlation between the measured and model predicted -log LC50 values both for the training (0.929) and validation (0.910) data and low prediction errors (RMSE) of 0.52 and 0.49 for two sets. Efficiency of the selected PNN and GRNN models in predicting acute toxicity of new chemicals was adequately validated using external datasets of different fish species (fathead minnow, bluegill, trout, and guppy). The PNN and GRNN models showed good predictive and generalization abilities and can be used as tools for predicting toxicities of structurally diverse chemical compounds. PMID:23764236

  19. First isolation of a rhabdovirus from perch Perca fluviatilis in Switzerland.

    Science.gov (United States)

    Wahli, Thomas; Bellec, Laure; von Siebenthal, Beat; Cabon, Joëlle; Schmidt-Posthaus, Heike; Morin, Thierry

    2015-10-16

    Perca fluviatilis is a fish species of increasing interest to the Swiss fish farming industry. In recent years, recirculation systems have been specifically set up to increase production. In one of these farms, abnormal spiral swimming associated with elevated mortalities occurred in repeated batches of imported perch shortly after stocking on several occasions. No bacterial or parasitic etiology was detected, but a virus grown in bluegill fry (BF-2) cells was identified as perch rhabdovirus. Subsequent investigations of other samples suggested a viral tropism for the central nervous system (CNS). Phylogenetic analysis of the partial N and entire G gene sequences positioned this isolate in genogroup C of the species Perch rhabdovirus, with high nucleotide and amino acid (aa) sequence identities with the DK5533 strain isolated in Denmark in 1989. Comparative studies using other closely related isolates allowed the distinction of 2 serological patterns among perch rhabdoviruses and the identification of a proline substitution by a serine in position 147 of the glycoprotein potentially involved in antigenic differentiation. Even if perch imported onto the farm tested negative by virus isolation prior to transport, they may have been the origin of this outbreak since CNS tissue was not included in the samples that were analyzed. Another possibility might be a sub-clinical infection with a viral load in resident fish too low to be detected. This study reports the first isolation of a perch rhabdovirus in Switzerland, and emphasizes the necessity of optimizing diagnostic tools that facilitate better control of the risks associated with fish translocation. PMID:26480912

  20. Electrofishing survey of the Great Miami River, September 1994 Annual Report

    International Nuclear Information System (INIS)

    Fish sampling by electroshocking in the Great Miami River upstream and downstream the Fernald site (September 25 and 26, 1994) was designed to determine changes in the health of the fish community compared to the previous ten years and to collect samples for uranium analyses in fish fillets. Samples of 853 fish, from 27 species, eight families and three sites at river mile (RM) 38, RM 24, and RM 19 provided seventy-eight samples for uranium analyses by an independent laboratory. The biomass of fish caught per hour was greatest at RM 24 > RM 19 > RM 3 8. The diversity index and the heaviest fish community was RM 24 > RM 38 > RM 19. The pooled site at RM 38 near Hamilton was diagnostically separated from the other sites by the young-of-the-year (YOY) golden redhorse, smallmouth bass and golden shiner. The darns at Hamilton acted as an effective barrier against fish migration upriver. Larger freshwater drum, gizzard shad, channel catfish and flathead catfish, which might be expected in rapid current reaches of mid-sized rivers characterize RM 24. The pool at RM 19 was distinguished from the others by YOY gizzard shad, bluegill, and longear sunfish. Thus the fish community in 1994 was separated ecologically by the physical features of the habitat more than by water quality differences between sites. These data suggest that the Fernald effluents in September were having no detectable effects on the distribution of fishes, independent of changes in habitat quality separated on physical attributes of the river channel at each site

  1. Environmental radiological studies conducted during 1986 in the vicinity of the Rancho Seco Nuclear Power Generating Station

    Energy Technology Data Exchange (ETDEWEB)

    Noshkin, V.E.; Wong, K.M.; Eagle, R.J.; Brunk, J.L.; Jokela, T.A.

    1987-03-01

    This report summarizes the information compiled in 1986 for our assessment of the environmental impact of radionuclides discharged with aqueous releases from the Rancho Seco Nuclear Power Generating Plant. In October 1984, a liquid-effluent control program was initiated that significantly reduced the quantities of radionuclides discharged with liquid waste from the plant. However, results from our sampling program in 1986 indicate that previously discharged radionuclides persist in the downstream environment and are found in many aquatic dietary components although at concentrations much lower than those measured in 1984 and 1985. The greatly reduced activities in the dietary components from the aquatic environment attest to the effectiveness of the liquid-effluent control program. Concentrations in the flesh of fish from the creeks have decreased over time and with distance from the plant outfall. The mean concentration of /sup 137/Cs in fish collected from Laguna Creek at locations more than 7.5 km from Rancho Seco is now comparable to the concentration determined in fresh-water fish randomly selected from Chicago, Illinois, markets. By August 1986, the mean concentration of /sup 137/Cs in the flesh of bluegill had fallen to 7% of the concentration measured in fish from comparable locations in 1984 and was 30% of the mean concentration measured in these fish during August 1985. Stable potassium in the water plays a major role in the accumulation of /sup 137/Cs by fish. Concentrations of /sup 137/Cs in the surface sections of creek sediments also declined between the end of 1984 and 1986 with an effective half-life of approximately 2 y. Surface soils collected around a perimeter 11 km from Rancho Seco and from ranchlands closer to the plant showed only concentrations of /sup 137/Cs originating from global fallout. Soils previously irrigated with Clay Creek water retain levels of both /sup 134/Cs and /sup 137/Cs.

  2. Heavy metals and arsenic concentrations in ten fish species from the Šalek lakes (Slovenia): assessment of potential human health risk due to fish consumption.

    Science.gov (United States)

    Al Sayegh Petkovšek, Samar; Mazej Grudnik, Zdenka; Pokorny, Boštjan

    2012-05-01

    The study, which measured the concentrations of Hg, Pb, Cd, Zn and As in various fish tissues (muscle, gill and liver) of 10 fish species (Abramis brama danubii, Alburnus alburnus alburnus, Barbus meridionalis petenyi, Carassius auratius gibelio, Cyprinus carpio, Lepomis gibossus, Leuciscius cephalus cephalus, Perca fluviatilis fluviatilis, Rutilus rutilus, Scardinus erythrophtlalmus erythrophtlalmus) collected in the Šalek lakes, is the first survey regarding metal concentrations in fish species with samples originating from Slovene lakes, while only a limited number of such studies have been carried out in southeastern Europe. Since these lakes are situated in the close vicinity of the largest Slovene thermal power plant, the study provides an insight into the potential impact of increased levels of metals in the environment as well as an estimate of the contamination of fish tissues with metals. Furthermore, it was possible to compare the results obtained with those from other studies regarding metal levels in freshwater fish species. The mean metal concentrations of different tissues irrespective of species varied in the following ranges: Zn 4.31-199 mg/kg ww, Pb 0.01-0.48 mg/kg ww, As 0.02-0.44 mg/kg ww, Hg <0.01-0.31 mg/kg ww, Cd < 0.01-0.19 mg/kg ww. In general, higher contents of Hg were found in muscles and livers than in gills and higher contents of As in gills and livers than in muscles, respectively. The accumulation of Pb and Zn was most pronounced in gills. The result obtained regarding metal concentrations in fish revealed that the ecosystems of the Šalek lakes are not polluted with Hg and Pb, slightly loaded with As and Cd and moderately polluted with Zn. In addition, the potential human health risk due to fish consumption was assessed. This showed that the estimated weekly intakes for all metals were far below provisional permissible tolerable weekly intakes determined by WHO/FAO. The consumption of fish from the Šalek lakes, therefore

  3. 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.

  4. 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

  5. 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.

  6. Hydrodynamics of C-Start Escape Responses of Fish as Studied with Simple Physical Models.

    Science.gov (United States)

    Witt, William C; Wen, Li; Lauder, George V

    2015-10-01

    One of the most-studied unsteady locomotor behaviors exhibited by fishes is the c-start escape response. Although the kinematics of these responses have been studied extensively and two well-defined kinematic stages have been documented, only a few studies have focused on hydrodynamic patterns generated by fishes executing escape behaviors. Previous work has shown that escape responses by bluegill sunfish generate three distinct vortex rings, each with central orthogonal jet flows, and here we extend this conclusion to two other species: stickleback and mosquitofish. Jet #1 is formed by the tail during Stage 1, and moves in the same direction as Stage-2 movement of the fish, thereby reducing final escape-velocity but also rotating the fish. Jet #2, in contrast, moves approximately opposite to the final direction of the fish's motion and contains the bulk of the total fluid-momentum powering the escape response. Jet #3 forms during Stage 2 in the mid-body region and moves in a direction approximately perpendicular to jets 1 and 2, across the direction of movement of the body. In this study, we used a mechanical controller to impulsively move passively flexible plastic panels of three different stiffnesses in heave, pitch, and heave + pitch motions to study the effects of stiffness on unsteady hydrodynamics of escape. We were able to produce kinematics very similar to those of fish c-starts and also to reproduce the 3-jet hydrodynamic pattern of the c-start using a panel of medium flexural stiffness and the combined heave + pitch motion. This medium-stiffness panel matched the measured stiffness of the near-tail region of fish bodies. This motion also produced positive power when the panel straightened during stage 2 of the escape response. More flexible and stiffer panels resulted in non-biological kinematics and patterns of flow for all motions. The use of simple flexible models with a mechanical controller and program of fish-like motion is a promising approach

  7. Disentangling the functional roles of morphology and motion in the swimming of fish.

    Science.gov (United States)

    Tytell, Eric D; Borazjani, Iman; Sotiropoulos, Fotis; Baker, T Vernon; Anderson, Erik J; Lauder, George V

    2010-12-01

    In fishes the shape of the body and the swimming mode generally are correlated. Slender-bodied fishes such as eels, lampreys, and many sharks tend to swim in the anguilliform mode, in which much of the body undulates at high amplitude. Fishes with broad tails and a narrow caudal peduncle, in contrast, tend to swim in the carangiform mode, in which the tail undulates at high amplitude. Such fishes also tend to have different wake structures. Carangiform swimmers generally produce two staggered vortices per tail beat and a strong downstream jet, while anguilliform swimmers produce a more complex wake, containing at least two pairs of vortices per tail beat and relatively little downstream flow. Are these differences a result of the different swimming modes or of the different body shapes, or both? Disentangling the functional roles requires a multipronged approach, using experiments on live fishes as well as computational simulations and physical models. We present experimental results from swimming eels (anguilliform), bluegill sunfish (carangiform), and rainbow trout (subcarangiform) that demonstrate differences in the wakes and in swimming performance. The swimming of mackerel and lamprey was also simulated computationally with realistic body shapes and both swimming modes: the normal carangiform mackerel and anguilliform lamprey, then an anguilliform mackerel and carangiform lamprey. The gross structure of simulated wakes (single versus double vortex row) depended strongly on Strouhal number, while body shape influenced the complexity of the vortex row, and the swimming mode had the weakest effect. Performance was affected even by small differences in the wakes: both experimental and computational results indicate that anguilliform swimmers are more efficient at lower swimming speeds, while carangiform swimmers are more efficient at high speed. At high Reynolds number, the lamprey-shaped swimmer produced a more complex wake than the mackerel-shaped swimmer

  8. Water Velocity and Bioturbation Alter Sediment Resuspension and Biogeochemistry in an Experimental Freshwater Mesocosm System

    Science.gov (United States)

    Spivak, A.; Vanni, M. J.

    2010-12-01

    Processes such as bioturbation and resuspension can affect organic matter decomposition by altering sediment redox conditions. Increased oxygen availability may, in turn, affect remineralization rates and larger scale processes such as benthic-pelagic coupling. However, relatively few studies have explicitly tested the simultaneous effects of bioturbation and water velocity on benthic biogeochemistry and sediment resuspension. Using a mesocosm system we conducted two experiments testing the effects of bioturbator identity on particulate and dissolved nutrient dynamics before and after a resuspension event (i.e. water velocity held constant at 0.12 m s-1 for 2 hr; Expt. 1) and rates of sediment resuspension with increasing water velocity (0.00 - 0.20 m s-1; Expt. 2). We manipulated bioturbator identity across four levels as sediments were undisturbed (control), manually punctured (2% of surface area), or disturbed by one of two fish species, either bluegill or catfish. For Expt. 1, the bioturbation treatments were applied for several days and measurements were made before and after the resuspension event. Initially, water column chlorophyll and total suspended sediment (TSS) concentrations were highest in the catfish treatments. Bioturbator identity did not affect the stoichiometry of TSS as strongly; C:N was unaffected by our treatments while N:P was lowest in the disturbed treatments. After the resuspension event, there was no difference in TSS concentrations or stoichiometric ratios across the bioturbation treatments. Dissolved nutrient flux rates were insensitive to the bioturbation treatments and were more strongly influenced by the resuspension event. For instance, sediment NO3- fluxes were negative (i.e. net flux into sediments) until after the resuspension event when they became positive. In Expt. 2, we gradually increased water velocity from 0.00 - 0.20 m s-1 and measured TSS concentrations only. TSS was initially highest in catfish treatments and lowest in

  9. Environmental Factors Affecting Mercury in Camp Far West Reservoir, California, 2001-03

    Science.gov (United States)

    Alpers, Charles N.; Stewart, A. Robin; Saiki, Michael K.; Marvin-DiPasquale, Mark C.; Topping, Brent R.; Rider, Kelly M.; Gallanthine, Steven K.; Kester, Cynthia A.; Rye, Robert O.; Antweiler, Ronald C.; De Wild, John F.

    2008-01-01

    water were observed in samples collected during summer from deepwater stations in the anoxic hypolimnion. In the shallow (less than 14 meters depth) oxic epilimnion, concentrations of methylmercury in unfiltered water were highest during the spring and lowest during the fall. The ratio of methylmercury to total mercury (MeHg/HgT) increased systematically from winter to spring to summer, largely in response to the progressive seasonal decrease in total mercury concentrations, but also to some extent because of increases in MeHg concentrations during summer. Water-quality data for Camp Far West Reservoir are used in conjunction with data from linked studies of sediment and biota to develop and refine a conceptual model for mercury methylation and bioaccumulation in the reservoir and the lower Bear River watershed. It is hypothesized that MeHg is produced by sulfate-reducing bacteria in the anoxic parts of the water column and in shallow bed sediment. Conditions were optimal for this process during late summer and fall. Previous work has indicated that Camp Far West Reservoir is a phosphate-limited system - molar ratios of inorganic nitrogen to inorganic phosphorus in filtered water were consistently greater than 16 (the Redfield ratio), sometimes by orders of magnitude. Therefore, concentrations of orthophosphate were expectedly very low or below detection at all stations during all seasons. It is further hypothesized that iron-reducing bacteria facilitate release of phosphorus from iron-rich sediments during summer and early fall, stimulating phytoplankton growth in the fall and winter, and that the MeHg produced in the hypolimnion and metalimnion is released to the entire water column in the late fall during reservoir destratification (vertical mixing). Mercury bioaccumulation factors (BAF) were computed using data from linked studies of biota spanning a range of trophic position: zooplankton, midge larvae, mayfly nymphs, crayfish, threadfin shad, bluegill,

  10. Vascular Plant and Vertebrate Inventory of Tumacacori National Historical Park

    Science.gov (United States)

    Powell, Brian F.; Albrecht, Eric W.; Halvorson, William L.; Schmidt, Cecilia A.; Anning, Pamela; Docherty, Kathleen

    2005-01-01

    Executive Summary This report summarizes the results of the first comprehensive biological inventory of Tumacacori National Historical Park (NHP) in southern Arizona. These surveys were part of a larger effort to inventory vascular plants and vertebrates in eight National Park Service units in Arizona and New Mexico. From 2000 to 2003 we surveyed for vascular plants and vertebrates (fish, amphibians, reptiles, birds, and mammals) at Tumacacori NHP to document presence of species within the administrative boundaries of the park's three units. Because we used repeatable study designs and standardized field techniques, these inventories can serve as the first step in a long-term monitoring program. We recorded 591 species at Tumacacori NHP, significantly increasing the number of known species for the park (Table 1). Species of note in each taxonomic group include: * Plants: second record in Arizona of muster John Henry, a non-native species that is ranked a 'Class A noxious weed' in California; * Amphibian: Great Plains narrow-mouthed toad; * Reptiles: eastern fence lizard and Sonoran mud turtle; * Birds: yellow-billed cuckoo, green kingfisher, and one observation of the endangered southwestern willow flycatcher; * Fishes: four native species including an important population of the endangered Gila topminnow in the Tumacacori Channel; * Mammals: black bear and all four species of skunk known to occur in Arizona. We recorded 79 non-native species (Table E.S.1), many of which are of management concern, including: Bermudagrass, tamarisk, western mosquitofish, largemouth bass, bluegill, sunfish, American bullfrog, feral cats and dogs, and cattle. We also noted an abundance of crayfish (a non-native invertebrate). We review some of the important non-native species and make recommendations to remove them or to minimize their impacts on the native biota of the park. Based on the observed species richness, Tumacacori NHP possesses high biological diversity of plants, fish